WO2025157949A1

WO2025157949A1 - System of electronic devices

Info

Publication number: WO2025157949A1
Application number: PCT/EP2025/051728
Authority: WO
Inventors: Andrew James KNIGHTS; Paul Daniel Baxter; Joshua David PERRIMAN
Original assignee: Lego AS
Current assignee: Lego AS
Priority date: 2024-01-25
Filing date: 2025-01-24
Publication date: 2025-07-31
Anticipated expiration: 2026-07-25

Abstract

The present invention relates in one aspect to a system comprising a plurality of electronic devices, the plurality of electronic devices comprising a first electronic device and a second electronic device, different from the first electronic device, wherein each electronic device of the plurality of electronic devices comprises: a contactless sensor for performing contactless sensing operations, and a processing unit, wherein the processing unit of the second electronic device of the plurality of electronic devices is configured to: perform an interference avoidance process to at least reduce the risk of another electronic device of the plurality of electronic devices, different from the second electronic device, performing an interfering contactless sensing operation concurrently with the second electronic device, and control the contactless sensor of the second electronic device to perform the contactless sensing operation conditioned on a risk of another electronic device performing a concurrent interfering contactless sensing operation being smaller than a threshold risk.

Description

System of electronic devices

The present disclosure relates in one aspect to a system comprising a plurality of electronic devices, wherein each electronic device comprises a contactless sensor configured to perform a contactless sensing operation, such as an automatic identification and/or data capture operation.

BACKGROUND

Systems of electronic devices are used for a variety of applications, in particular as modular, wireless interactive toys that can read wireless tags or perform other contactless sensing operations.

US2021134181 discloses an educational toy that includes a self-moving vehicle adapted to move and steer freely on a two-dimensional surface such as a table leaf. A tangible, three-dimensional marker includes at least one RFID tag and is used to wirelessly trigger a specific action of the vehicle, e.g. turn 90 degrees right, when the vehicle enters a readout range of the marker.

In environments where multiple electronic devices perform contactless sensing operations there is a risk that the contactless sensing operations interfere with each other and cause malfunction or delays in the performance of the contactless sensing operations or other undesired effects.

In the context of an interactive toy system, children or other users of the toy system may arrange, and repeatedly re-arrange, multiple wireless interactive toys in relative close proximity to one another, including in configurations not originally foreseen. For example, when the wireless interactive toys are wireless interactive toy construction elements, a child or other user may construct a variety of different toy construction models, which may include multiple wireless interactive toys. It is therefore beneficial, when an interactive toy system can seamlessly and without need for complicated user configuration cope with a large variety of situations while ensuring proper functioning of the toy system. In particular, the contactless sensing operations performed by the wireless interactive toys should be performed reliably and efficiently. It is generally desirable to provide a system of electronic devices, in particular interactive wireless toys, that allows multiple electronic devices to perform contactless sensing operations at a high rate with no or only little risk that the contactless sensing operations interfere with another even when the interactive wireless toys are used in the same general proximity of another, e.g. within the same room, while positioned on the same table, or the like.

It is further desirable to provide a system of electronic devices that is robust and operates reliably.

It is further desirable to provide a system of electronic devices that operates with low power consumption.

It is further desirable to provide a system of electronic devices that requires little communications overhead.

It is further desirable to provide a system of electronic devices that can easily be operated by a user, in particular a child, with little or no need for user configuration.

It is further desirable to provide a system of electronic devices that can be manufactured at low cost.

It is further desirable to provide a system of electronic devices that is scalable.

On this background, despite previous efforts, it remains desirable to provide a system that solves one or more of the above problems and/or other problems, and/or that has other benefits, or that at least provides an alternative to existing solutions.

SUMMARY

According to one aspect, the present disclosure relates to a system comprising a plurality of electronic devices, including a first electronic device and a second electronic device. Each electronic device comprises:

- a contactless sensor for performing contactless sensing operations, and - a processing unit.

The processing unit of the second electronic device of the plurality of electronic devices is configured to:

- perform an interference avoidance process to eliminate, or at least reduce, the risk of another electronic device of the plurality of electronic devices, different from the second electronic device, performing an interfering contactless sensing operation concurrently with the second electronic device, and

- control the contactless sensor of the second electronic device to perform the contactless sensing operation conditioned on a risk of another electronic device performing a concurrent interfering contactless sensing operation being smaller than a threshold risk.

An interfering contactless sensing operation is a contactless sensing operation performed by another one of the electronic devices where concurrent performance of the contactless sensing operation of the second electronic device and the interfering contactless sensing operation results in interference between the contactless sensing operation of the second electronic device and the interfering contactless sensing operation, in particular an interference that affects the result of, or otherwise disturbs, the contactless sensing operation performed by the second electronic device and/or the interfering contactless sensing operation.

In some embodiments, the system employs a shared schedule to reserve times for respective ones of the electronic devices to allow the electronic devices to perform contactless sensing operations during their respective reserved times with no or little risk of interference.

Accordingly, in some embodiments, the processing unit of each electronic device is configured to control the contactless sensor to perform one or more scheduled contactless sensing operations according to a shared schedule. The shared schedule assigns reserved times to respective ones of the plurality of electronic devices. Each reserved time is indicative of a time reserved for a selected one of the electronic devices to perform at least one scheduled contactless sensing operation. The shared schedule includes a first reserved time, reserved for the first electronic device to perform at least one scheduled contactless sensing operation. The electronic devices can thus use the shared schedule to coordinate contactless sensing operations, in particular to allow the electronic devices to perform contactless sensing operations at the times reserved for them according to the shared schedule. Such scheduled sensing operations can thus be performed with no or minimal risk of interference by contactless sensing operations performed by other electronic devices of the system. The term “scheduled contactless sensing operation” thus refers to a contactless sensing operation, which is performed by one of the electronic devices, and which is performed at a time reserved by the shared schedule for said electronic device, which performs the contactless sensing operation.

Accordingly, the risk of interference is reduced as the electronic devices generally adhere to a shared schedule when performing the contactless sensing operation. The provision of a shared schedule allows the system to provide opportunities for the electronic devices to perform the scheduled contactless sensing operations without risk - or at least reduced risk - of interference from other devices.

In addition to the scheduled contactless sensing operations, the electronic devices may perform unscheduled contactless sensing operation. In particular, a contactless sensing operation performed by the contactless sensor of the second electronic device at the first reserved time is referred to as an unscheduled sensing operation because it is performed at a time that is reserved for the first electronic device and not for the second electronic device. The contactless sensing operation performed by the contactless sensor of the second electronic device at the first reserved time is thus not a scheduled contactless sensing operation performed according to the shared schedule, but instead an unscheduled contactless sensing operation performed in addition to the scheduled contactless sensing operations according to the shared schedule.

For the purpose of the present disclosure, the term “unscheduled contactless sensing operation” thus refers to a contactless sensing operation performed by one of the electronic devices at a time, which is not reserved for said electronic device by the shared schedule, in particular at a time, which instead is reserved for another electronic device of the system.

In various embodiments disclosed herein, each electronic device is configured to perform unscheduled contactless sensing operations at a reserved time, which is reserved for another electronic device, only when the electronic device has determined that the interference risk is sufficiently low.

To this end, in various embodiments, the electronic devices may use the distance to other electronic devices of the system as a measure of the interference risk. Accordingly, in some embodiments, the processing unit of the second electronic device is further configured to:

- obtain distance information about a distance between the first electronic device and the second electronic device; and

- control the contactless sensor of the second electronic device to perform at least one unscheduled contactless sensing operation at the first reserved time when the obtained distance is larger than a threshold distance.

By reusing a reserved time assigned to another electronic device for an additional, unscheduled contactless sensing operation, conditioned on the distance between the devices being larger than a threshold distance, the second electronic device may increase the rate at which it can perform the contactless sensing operations without unduly increasing the risk of interference. Accordingly, the system is capable of performing contactless sensing operations at a high rate while reducing the risk of interference, even when the number of electronic devices in the system increases.

Interference between contactless sensing operations performed by different electronic devices has a limited/reduced effect over distance, i.e. the interference decreases as the distance between the devices increases. The threshold distance may thus be selected based on an interference range of the contactless sensing operation. In particular, the threshold distance may be selected to be equal to, or larger than, an interference range of the contactless sensing operations. The interference range may be determined or estimated as a range between two electronic devices beyond which the contactless sensing operation performed by one of the devices no longer interferes with a concurrent sensing operation performed by the other electronic device, or only interferes to an acceptably low degree. It will be appreciated that the determination of the interference range may depend on the specific nature and sensitivity of the contactless sensing operations, e.g. on required sensitivity or accuracy of the contactless sensing operations. Accordingly, performing unscheduled contactless sensing operations only when the distance between the devices is larger than a suitably selected threshold distance allows the performance of the unscheduled contactless sensing operations to be restricted to situations when the distance between the electronic devices is larger than the known, estimated or expected interference range. The distance information may thus be considered a risk measure of a risk of interference between respective contactless sensing operations performed by the first electronic device and the second electronic device. The threshold distance represents a measure of an acceptable risk threshold. In other embodiments, the system may employ a different measure or indicator of the interference risk, e.g. a detected signal strength, and the threshold risk may thus be defined in another suitable manner.

According to a more general aspect, the plurality of electronic devices comprises a first electronic device and a second electronic device, different from the first electronic device. The shared schedule includes a first reserved time, reserved for the first electronic device. The processing unit of the second electronic device is further configured to:

- obtain a risk measure indicative of a risk of interference between respective contactless sensing operations performed by the first electronic device and the second electronic device; and

- control the contactless sensor of the second electronic device to perform at least one unscheduled contactless sensing operation at the first reserved time when the interference risk is below a risk threshold.

In particular, the risk measure may include distance information about a distance between the first electronic device and the second electronic device. Accordingly, the risk threshold may correspond to a threshold distance, where the interference risk being lower than the risk threshold corresponds to the distance between the first electronic device and the second electronic device being larger than the threshold distance.

As the shared schedule provides reserved times for the respective electronic devices to perform scheduled contactless sensing operations, an electronic device may not need to obtain a risk measure in connection with the performance of the scheduled contactless sensing operations at the reserved times, which are reserved for said electronic device. Accordingly, the shared schedule may include a second reserved time, reserved for the second electronic device to perform at least one scheduled contactless sensing operation, and the processing unit of the second electronic device may be configured to perform one or more scheduled contactless sensing operations at the second reserved time. In particular, the processing unit of the second electronic device may be configured to perform the one or more scheduled contactless sensing operations at the second reserved time without prior evaluation by the second electronic device of an interference risk based on an obtained risk measure. In other embodiments the electronic devices may also perform an evaluation of interference risk when performing scheduled contactless sensor operations.

In some embodiments, one or more other electronic devices, e.g. all electronic devices, of the plurality of electronic devices may be configured to perform corresponding processes of obtaining distance information about distances to respective other ones of the electronic devices, and to perform one or more unscheduled contactless sensing operations at a reserved time, which is reserved to another one of the electronic devices, when the obtained distance to said another electronic device is larger than a threshold distance.

Each electronic device may be individually movable within a space, independently from the other electronic devices of the system. Movement of one or more of the electronic devices may thus change the relative positions of the electronic devices relative to each other, in particular the relative distance of the electronic devices from each other. In particular, the space may be a shared space, shared by the plurality of electronic devices. In some embodiments, the system is an interactive toy system and each of the electronic devices is a wireless interactive toy. In particular, the interactive toy system may be an interactive toy construction system, and each wireless interactive toy is or comprises a wireless interactive toy construction element. For example, each wireless interactive toy may be an individual one of the interactive toy construction elements, or a toy construction model constructed from two or more toy construction elements of the toy construction systems, including at least one interactive toy construction element.

Various embodiments of the system may perform various types of contactless sensing operations, in particular sensing operations for sensing a property of the environment of the electronic device performing the contactless sensing operation.

In some embodiments, the contactless sensing operation comprises a contactless sensing operation for detecting a presence of an object in a proximity of the electronic device and/or for identifying an identity of an object in a proximity of the electronic device and/or to capture data from an object in a proximity of the electronic device. The contactless sensing operation may comprise a capacitive measurement, an inductive measurement, a measurement of an electric and/or magnetic field, in particular an electro-magnetic field, and/or the like. In some embodiments, the contactless sensing operation comprises a magnetic sensing operation for sensing a magnetic field in a proximity of the electronic device. It will be appreciated that the terms “scheduled” and “unscheduled” in the context of contactless sensing operations merely indicate whether or not the contactless sensing operation is performed at a time that is reserved by the shared schedule for the electronic device performing the contactless sensing operation. The terms “scheduled” and “unscheduled” are not intended to imply that the type of contactless sensing operations, which are performed as scheduled or unscheduled contactless sensing operations, necessarily differ. Accordingly, the scheduled and unscheduled contactless sensing operation may be the same or different types of contactless sensing operations. Moreover, the electronic devices may perform the same type of contactless sensing operations at different reserved times and/or they may perform different types of contactless sensing operations at different reserved times. For example, a first type of sensing operation may involve the detection of the presence of an object, e.g. a data-carrying object, in the proximity of the electronic device. A second type of sensing operation may involve the reading or otherwise capturing of data from a data-carrying object. The mere detection of the object may be a fast operation while the data capture may require a longer time, depending on the amount of data to be read. For example, an electronic device may perform the first type of sensing operation as a scheduled sensing operation to obtain an inventory of objects in its vicinity. The electronic device may then perform subsequent scheduled and/or unscheduled contactless sensing operations of the second type to obtain data from the identified objects. Alternatively, or additionally, the electronic device may perform subsequent scheduled or unscheduled contactless sensing operations of the first type in order to obtain an updated inventory of objects in the proximity of the electronic device.

The contactless sensor may include any circuitry or device suitable for performing the contactless sensing operation. In particular, the contactless sensor may include one or more suitable sensor probes, such as one or more capacitive sensing elements, inductive sensing elements, antennae, coils, and/or the like. In some embodiments, the contactless sensor includes one or more sensor probes for sensing a magnetic and/or electric field and for creating an electric sensor signal responsive to the sensed electric and/or magnetic field. The contactless sensor may further comprise a sensor circuit for processing electric sensor signals from the one or more sensor probes and for feeding the processed sensor signals to the processing unit. The or each sensor probe may include one or more inductors, in particular one or more coils.

The contactless sensing operation may be an individual contactless sensing operation of a single electronic device, i.e. a contactless sensing operation in which only one of the plurality of electronic devices participates. It will be appreciated, however, that other objects, different from the other electronic devices, may participate in or be the subject of the contactless sensing operation. Examples of such other objects include wireless tags. The object being sensed may be passive or it may actively contribute to the sensing operation, e.g. by emitting an electric and/or magnetic field that can be sensed by the sensor of the electronic device.

The contactless sensing operation may comprise the electronic device outputting, e.g. via one or more of the sensor probes, an interrogation signal and sensing a re- sponse to the emitted interrogation signal. The interrogation signal may be an electric and/or magnetic signal, in particular an electro-magnetic signal, such as a radiofrequency signal. Accordingly, the electronic device may include a transmitter or other signal generator coupled to the sensor probe for generating the interrogation signal. The electronic device may include a receiver coupled to the sensor probe for receiving the response signal. The transmitter and receiver may be formed as separate circuits or as a single combined circuit, e.g. as a transceiver circuit. The transmitter and/or receiver may be implemented at least in part by the sensor circuit and/or at least in part by the processing unit.

The contactless sensing operation may be a short-range contactless sensing operation, in particular an operation having an effective range of less than 50 cm, such as less than 20 cm, such as less than 10 cm. In particular, in the context of a wireless sensing operation, the effective range is indicative of a maximum distance at which the electronic device can sense the property to be sensed, e.g. a maximum distance at which the electronic device can detect and/or identify and/or capture data from an object in a proximity of the electronic device.

For the purpose of the present disclosure, the term contactless sensing is intended to refer to sensing operations that do not rely on, or otherwise require mechanical or even conductive coupling with an object to be sensed, in particular without transfer of electrical or other energy by means of physical contact via a conductive medium that is conductive for a direct current. It will be appreciated that the term contactless merely characterises the contactless sensing operation and does not exclude that the electronic device is otherwise physically connected with the object being sensed or operated on. In particular the electronic device may be in physical contact with the object being sensed, e.g. mechanically interconnected with the object being sensed by means of respective coupling members. However, the sensing operation is contactless, i.e. does not rely on the physical contact as a carrier for energy, forces, information, or the like.

In some embodiments, some or all of the contactless sensing operations comprise a wireless tag sensing operation and/or other forms of automatic identification and/or data capture operation. Generally, examples of automatic identification and/or data capture operations include the detection and/or identification of one or more wireless tags, such as RFID tags or other types of wireless tags that are detectable by means of electric and/or magnetic fields or waves, in particular by radio-frequency signals.

To this end, the wireless system may comprise one or more wireless tag elements that are detectable by each of the electronic devices when positioned in a proximity of said electronic device. Examples of wireless tag elements include objects, such as toy construction elements, comprising an RFID tag or other suitable wireless tag. The proximity may be defined by a detection range of the wireless detection mechanism. In some embodiments, the detection range is less than 50 cm, such as less than 20 cm, such as less than 10 cm. In some embodiments, the contactless sensing operation may comprise the electronic device emitting an interrogation signal, in particular a radio-frequency interrogation signal, and detecting a response signal from the wireless tag element, e.g. a modulation of the interrogation signal. The response signal may be indicative of a tag identifier of the wireless tag element and/or of other data stored by the wireless tag element. The electronic device, in particular the wireless interactive toy, may be configured to perform one or more user-detectable functions responsive to the detection of a wireless tag element in its proximity and/or responsive to the tag identifier and/or other data captured from the wireless tag element.

In some embodiments, the wireless tag elements are different from the electronic devices. In particular the wireless tag elements may differ from the electronic devices in a variety of ways. For example, in some embodiments, only the electronic devices are configured to perform contactless sensing operations. Alternatively, or additionally, in some embodiments, only the electronic devices are configured to perform a position and/or orientation sensing as described below and/or wireless communication via a wireless communications network as described below. The wireless tag elements may thus lack one, some or all of the above capabilities and merely react to an interrogation signal. Yet alternatively or additionally, in some embodiments, only the electronic devices comprise a power source such as a battery or other power storage device for storing electrical energy over an extended period of time. The electronic devices may be configured to transfer operating power to the tag element so as to allow the tag element to respond to the interrogation signal when being interrogated and energized by the electronic device. In particular, the electronic device may transfer power wirelessly, in particular via the interrogation signal. Accordingly, the tag element may be configured to harvest the energy from the interrogation signal and to use the harvested power as operating energy for performing its function, in particular for responding to the interrogation signal. The tag element may thus lack a power storage device for storing electrical energy over an extended period of time, e.g. for more than 1 minute.

In some embodiments, the tag elements have a shape and/or size different from the electronic devices, thereby allowing the user to readily distinguish the different types of components of the system from each other. In some embodiments, the tag elements are smaller than the electronic devices, in particular smaller by volume. For example, in some embodiments, some tag elements, or even each tag element, may have volume of less than 75% of each of the electronic devices, such as less than 50%, such as less than 25%. In other embodiments, at least some of the tag elements may be larger than some or all of the electronic devices.

In the context of an interactive toy system, the user may move around the wireless interactive toys and/or the tag elements as part of a play experience. The wireless interactive toys may be configured to detect the user's interactions with components of the interactive toy system and react to the detected interactions by providing user- perceptible outputs, e.g. including audible, visual and/or haptic outputs. In embodiments where the wireless interactive toys and the wireless tag elements are toy construction elements of a toy construction system, the user may repeatedly attach and/or detach the wireless interactive toy construction elements and/or the wireless tag construction elements to/from one another and/or to/from other toy construction elements of the toy construction system so as to construct and deconstruct different spatial structures. Spatial structures constructed from two or more toy construction elements will also be referred to as toy construction models. They may repeatedly be constructed and disassembled without destroying the toy construction elements from which they are constructed. It is highly desirable that the wireless interactive toys have a short response time to changes in the relative positions of the wireless tag elements and the wireless interactive toys, such that the user perceives a detectable reaction without - or at least with only little - undue delays when the user moves the components of the toy system relative to each other. For example, when the wireless interactive toy is moved by the user into a proximity of a detectable wireless tag, it is desirable that the wireless toy reacts to this user action without too long delays. Accordingly, it is desirable, that the wireless interactive toys perform the contactless sensing operations for automatic identification and/or data capture reliably and at a sufficiently high rate to facilitate a fast response time and to avoid, or at least reduce, delays that might be noticeable by the user.

The second electronic device may obtain the distance information in a variety of ways. In some embodiments, the second electronic device may be configured to perform a distance measurement, either on its own or in cooperation with one or more of the other electronic devices, e.g. in cooperation with the first electronic device. For example, the electronic devices may be configured to perform position sensing operations, e.g. as described below, or otherwise. Alternatively, or additionally, the processing unit of the second electronic device may obtain the distance information from received signal strength determinations when communicating with other electronic devices of the plurality of electronic device. To this end, the second electronic device may determine a received signal strength indicator (RSSI) when communicating via a wireless communications network, e.g. as described below, or otherwise, or the second electronic device may receive received signal strength indicators from other electronic devices of the system. The second electronic device may thus use the RSSI as a measure of the distance between the first and second electronic devices or, more generally, as a risk measure of the risk of interference. Yet alternatively or additionally, the processing unit of the second electronic device may receive the distance information from one or more of the other electronic devices of the system, e.g. from the first electronic device. The second electronic device may receive the distance information via a wireless communications network, e.g. as described below, or otherwise. In some embodiments, the second electronic device may measure the distance to one or more electronic devices and receive dis- tance information about distances to other electronic devices. In some embodiments, the second electronic device may derive additional distance information from the received distance information and/or the measured distances, e.g. by using triangulation or other techniques.

In some embodiments, the electronic devices are configured to perform magnetic position and/or orientation sensing. In particular the electronic devices may be configured to perform magnetic position operations to determine distances between respective ones of the electronic devices. The contactless sensing operations may include the magnetic position and/or orientation sensing operations. Alternatively, the electronic devices may be configured to perform the magnetic position and/or orientation sensing in addition to the contactless sensing operations, i.e. the contactless sensing operation may be different from the magnetic position and/or orientation sensing operation. The magnetic position sensing operation may have a position sensing range, i.e. a maximum range at which one electronic device may still determine a position of another electronic device relative to its own position, where the position sensing range may be larger than an interference range of said contactless sensing operation, i.e. larger than a range at which the contactless sensing operation performed by the second device may interfere with the contactless sensing operation performed by the first device. For example, the position sensing range may be at least 1 m, such as at least 2 m, such as at least 5 m. Similarly, the magnetic orientation sensing operation may have an orientation sensing range, which may be equal to or different from, in particular smaller than, the position sensing range.

In some embodiments, the magnetic position and/or orientation sensing operation may be configured to provide relative position and/or orientation information about the relative position of two electronic devices relative to another and/or about the relative orientation between the two devices relative to each other. The information about the relative position may include the distance between the two electronic devices. In some embodiments, the second electronic device may thus determine a direction from the second towards the first electronic device, e.g. relative to a local coordinate system of the second electronic device. The measured position information may include two or three spatial coordinates. Similarly, the determined orientation may be a relative orientation of the first electronic device relative to an internal coordinate system of the second electronic device. The rotation information may include one, two, or even three orientation coordinates.

In some embodiments, the electronic devices may be configured to perform the position and/or orientation sensing operation in a cooperative manner. To this end, each electronic device may be configured to output a probe magnetic field that may be sensed by one or more of the other electronic devices. Moreover, each electronic device may be configured to sense a probe magnetic field output by another one of the electronic devices and to compute at least a relative position of the another electronic device based at least on the sensed probe signal. The relative position may include a distance and, optionally, additional one or two directional coordinates.

Accordingly, in some embodiments, each electronic device comprises a magnetic position and/or orientation sensor device configured to perform one or more magnetic position and/or orientation sensing operations for determining relative positions and/or relative orientation of respective ones of the electronic devices. The magnetic position and/or orientation sensor device may be configured to determine the relative position and/or relative orientation to one or more other electronic devices on its own or in cooperation with one or more of said other electronic device. The magnetic position and/or orientation sensor device may thus be operable as an independent magnetic position and/or orientation sensor or it may be a component of a magnetic position and/or orientation sensor system, e.g. of a multi-component sensor system that includes a transmitter or other signal generator of a transmitting electronic device for generating a probe magnetic field and a sensor probe of another, receiving electronic device for detecting a probe signal generated by the transmitter of the transmitting electronic device. The magnetic position and/or orientation sensor device may include any position and/or orientation sensing circuit or device suitable for performing the position and/or orientation sensing operation. In particular, each electronic device may include one or more suitable position and/or orientation sensor probes, such as one or more inductors, e.g. one or more coils, and/or the like, and associated electronic position and/or orientation sensing circuitry. The associated electronic position and/or orientation sensing circuitry may at least in part be implemented by the processing unit of the electronic device. The position and/or orientation sensing operation performed by the magnetic position and/or orientation sensor device of one electronic device may result in one or more determined relative positions and/or relative orientations on its own, or it may contribute to a cooperative determination of one or more relative positions and/or relative orientations, or otherwise.

Each electronic device may include a transmitter or other signal generator, which may be coupled to the position and/or orientation sensor probe, or to another probe, for generating the probe magnetic field. The electronic device may include a receiver circuit coupled to the position and/or orientation sensor probe for sensing a probe magnetic field generated by another electronic device. The transmitter and receiver may be formed as separate circuits or as a single combined circuit, e.g. as a transceiver circuit. The transmitter and/or receiver may be implemented at least in part by the electronic position and/or orientation sensing circuitry and/or at least in part by the processing unit. The processing unit of the electronic device may be configured to compute at least a distance to the another electronic device based at least on the sensed probe signal and, optionally additional directional information and/or orientation information.

The position and/or orientation sensor device may be separate from the contactless sensor or it may be partly or completely be integrated therewith or otherwise implemented at least in part by one or more shared hardware components of the electronic device. For example, the position and/or orientation sensor device and the contactless sensor may share the same sensor probes, e.g. the same coils, and at least a part of the transmitter and/or receiver circuitry.

As described above, the contactless sensing operation may be different from the position and/or orientation sensing operations. For example, the contactless sensor operations may be individual sensing operations, such as wireless tag sensing operations, that are performed separately and individually by each electronic device without involvement from the other electronic devices. The position and/or orientation sensing operations may be cooperative sensing operations performed by more than one electronic device in cooperation with each other. In some embodiments, the electronic device may be configured to selectively perform the contactless sensing operations and the position sensing operation non-concurrently, i.e. alternatingly or otherwise at respective times. In particular, the electronic device may be configured to only perform one of the contactless sensing operation and the position and/or orientation sensing operation at any given time, thereby allowing the re-use of hardware components for both operations and avoiding undesired interference between both operations.

The second electronic device may obtain the distance information directly or indirectly from one or more magnetic position sensing operations performed by two or more of the electronic devices. In some embodiments, the second electronic device is configured to obtain the distance information at least by performing said magnetic position sensing operation. For example, the second electronic device may sense the distance to the first electronic device using the magnetic position sensing operation. Alternatively, or additionally, the first electronic device may sense the distance between the second electronic device and the first electronic device using the magnetic position sensing operation and transmit the sensed distance information directly or indirectly (e.g. via another one of the electronic devices) to the second electronic device. Yet further, the second electronic device may obtain the distance information indirectly. For example, both the first and the second electronic device may obtain their respective relative positions and/or orientations relative to a third electronic device, and share the measured position and/or orientation information with one or more of the other electronic devices. One or more of the electronic devices, e.g. the second electronic device, may then determine, or at least estimate the distance between the first and second electronic devices. The electronic devices may use the sensed position and/or orientation information for other purposes than for determining reserved times that may be reused for unscheduled contactless sensing operations. For example, the electronic devices may use the sensed position and/or orientation information to detect user interactions with the electronic devices and to determine interactive responses to the detected user interactions, e.g. as part of a play experience executed by the electronic devices.

In some embodiments, the electronic devices are configured to wirelessly communicate with each other via a wireless communications network. Accordingly, in some embodiments, each electronic device comprises a wireless communications interface configured for wireless communication via a wireless communications network and wherein the electronic devices are configured to wirelessly communicate with each other via said wireless communications network. The wireless communication may be based on a suitable radio-frequency communication technology, e.g. using the Bluetooth protocol, Bluetooth Low-energy, ZigBee, Wifi, and/or the like. In some embodiments, the wireless communication may comprise broadcasting one or more messages by one or more of the electronic devices via the wireless communications network to the other electronic devices of the plurality of electronic devices. The wireless communication is different from said contactless sensing operation. The wireless communications interface may comprise a radio transceiver, e.g. a Bluetooth chip or circuit, and an associated antenna.

The wireless communication between the electronic devices may be a short-range wireless communication having a communications range of e.g. less than 100 m, such as less than 10 m. In some embodiments, the communications range may be at least 2 m, such as at least 3 m, such as at least 5 m. The communications range is preferably larger than the interference range of the contactless sensing operation, e.g. at least 10 times larger or even more. The communications range may also be larger than the range of the position and/or orientation sensing operation.

In some embodiments, the processing unit of the second electronic device is configured to obtain the distance information at least based on a communication signal received by the wireless communications interface of the second electronic device from the first electronic device via said wireless communications network, in particular at least by determining a received signal strength indicator associated with said received communications signal. It will be appreciated that, in some embodiments, the processing unit of the second electronic device may determine the distance information from a combination of the received signal strength and the magnetic position sensing operation.

The electronic devices may use the wireless communications network to coordinate operation of the system of electronic devices. For example, the plurality of electronic devices may be configured to share the shared schedule via said wireless communications network. Alternatively, or additionally, the plurality of electronic devices may be configured to share measured distance information and/or further position and/or orientation information via the wireless communication.

The wireless communications network may be an open network in the sense that electronic devices may join and leave the network at any time, i.e. such that the number of electronic devices within the communications network may vary over time, optionally up to a predetermined maximum number of electronic devices. The wireless communications network may be closed in the sense that only electronic devices of the system of electronic devices may join and communicate via the wireless communications network. The latter may e.g. be enforced by requiring a predetermined identifier, address, key, encryption scheme and/or the like.

The shared schedule comprises an indication of times that are reserved for respective electronic devices to perform scheduled contactless sensing operations. Each reserved time may be indicative of one or more time slots, in particular one or more consecutive time slots, each time slot having a predetermined length.

The shared schedule is shared by at least a subset, or even all, of the electronic devices, e.g. by all electronic devices currently communicating with each other via the same wireless communications network. In some embodiments, the plurality of electronic devices comprise a scheduler device configured to create the shared schedule and to distribute/broadcast the shared schedule to the other electronic devices of the plurality of electronic devices, e.g. via said wireless communications network. It will be appreciated that the shared schedule may be created in a variety of ways. For example, the schedule may be predetermined and/or static, or it may be dynamic, e.g. adapted to the number of electronic devices currently participating in the wireless communications network, adapted to a currently executed play experience, etc.

In some embodiments, the shared schedule includes reserved times for performing multiple types of contactless sensing operations and/or other operations. For example, in some embodiments, the shared schedule includes respective times reserved for wireless tag sensing operations and respective reserved times for performing the magnetic position and/or orientation sensing operations.

The shared schedule may reserve times for individual contactless sensing operations, reserved for selected individual electronic devices to perform their respective scheduled contactless sensing operations. The shared schedule may additionally reserve times for cooperative contactless sensing operations, in which more than one, such as all, of the electronic devices participate in a synchronized manner. For example, certain embodiments of the magnetic position and/or orientation sensing described herein are cooperative contactless sensing operations.

Sharing the schedule among the electronic devices allows each electronic device to perform cooperative contactless sensing operations in a synchronized manner. Sharing the schedule also allows the electronic devices to identify one or more times that are reserved for other electronic devices, which are sufficiently far away to allow said electronic device to use the identified reserved times to perform additional, unscheduled contactless sensing operations even though the time(s) is/are reserved for another electronic device.

In some embodiments, the shared schedule includes a second reserved time, reserved for said second electronic device. The processing unit of the second electronic device may further be configured to:

- control the contactless sensor of the second electronic device to perform at least one scheduled contactless sensing operation at the second reserved time,

- obtain distance information about a distance between the first electronic device and the second electronic device, and

- control the contactless sensor of the second electronic device to additionally perform at least one unscheduled contactless sensing operation at the first reserved time when the obtained distance is larger than a threshold distance.

Alternatively, the shared schedule includes a second reserved time, reserved for the second electronic device, and wherein the processing unit of the second electronic device is configured to: - obtain distance information about a distance between the first electronic device and the second electronic device,

- control the contactless sensor of the second electronic device to perform at least one unscheduled contactless sensing operation at the first reserved time when the obtained distance is larger than a threshold distance,

- omit performing a scheduled contactless sensing operation at the second reserved time, and, optionally communicating, e.g. broadcasting, to one or more of the other electronic devices that the second reserved time is available for unscheduled contactless sensing operations by other electronic devices.

There may be situations where two or more electronic devices determine to reuse the same reserved time for their own unscheduled contactless sensing operation. When these two or more electronic devices are positioned too close to each other, their unscheduled contactless sensing operations may interfere with each other and result in malfunctions or delays.

Accordingly, in some embodiments, the processing unit of the second electronic device is configured to, when the obtained distance is larger than a threshold distance:

- perform an interference avoidance process to eliminate or at least reduce the risk of a third electronic device of the plurality of electronic devices, different from the first electronic device, performing an unscheduled contactless sensing operation at the first reserved time, and

- control the contactless sensor to perform the contactless sensing operation at the first time conditioned on a result of the performed interference avoidance process, in particular conditioned on a risk of another electronic device performing an unscheduled contactless sensing operation at the first reserved time being smaller than a threshold risk.

To this end, the second electronic device may perform any suitable interference avoidance strategy known as such in the art, e.g. using random back-off times if clashes are detected.

In some embodiments, the system may employ such interference avoidance strategies more generally, e.g. in addition to or as an alternative to the use of a shared schedule. Accordingly, in another aspect disclosed herein, the system may dispense with the shared schedule.

Generally, the processing unit of the electronic device according to various aspects disclosed herein may be implemented as any suitable processing circuitry or device, e.g. as one or more suitably programmed microprocessor or other processing device, e.g. as one or more ASICs, one or more microcontrollers, and/or one or more other suitable processing units, or combinations thereof.

The present disclosure relates to different aspects including the system described above and in the following, corresponding apparatus, systems, methods, and/or products, each yielding one or more of the benefits and advantages described in connection with one or more of the other aspects, and each having one or more embodiments corresponding to the embodiments described in connection with one or more of the other aspects and/or disclosed in the appended claims.

In particular, according to one aspect, disclosed herein are embodiments of an electronic device for use in a system of electronic devices, in particular in a system as described above and in the following.

In some embodiments, the electronic device comprises:

- a contactless sensor for performing contactless sensing operations, and

- a processing unit, wherein the processing unit is configured to:

- perform an interference avoidance process to at least reduce the risk of another electronic device of the system of electronic devices performing an interfering contactless sensing operation concurrently with said electronic device, and

- control the contactless sensor of the electronic device to perform the contactless sensing operation conditioned on a risk of another electronic device performing a concurrent interfering contactless sensing operation being smaller than a threshold risk. In some embodiments, the processing unit is configured to control the contactless sensor to perform one or more scheduled contactless sensing operations according to a shared schedule, the shared schedule assigning access times to respective ones of the plurality of electronic devices, each access time being indicative of a time reserved for a selected one of the electronic devices to perform the contactless sensing operation; wherein the processing unit is further configured to:

- control the contactless sensor of the second electronic device to perform at least one unscheduled contactless sensing operation at the first reserved time when the interference risk is below a threshold risk.

In some embodiments, the electronic device comprises:

- a contactless sensor for perform contactless sensing operations, and

- a processing unit configured to control the contactless sensor to perform one or more scheduled contactless sensing operations according to a shared schedule, the shared schedule assigning access times to respective ones of the plurality of electronic devices, each access time being indicative of a time reserved for a selected one of the electronic devices to perform the contactless sensing operation. The processing unit is further configured to:

- obtain distance information about a distance between the electronic device and another electronic device of the plurality of electronic devices; and

- control, when the obtained distance is larger than a threshold distance, the contactless sensor to perform at least one unscheduled sensing operation during one of the reserved times, said one of the reserved times being reserved for said another electronic device.

In some embodiments, the electronic device is a wireless interactive toy, in particular a wireless interactive toy construction element. Accordingly, according to another aspect, the present disclosure relates to a toy construction system comprising a plurality of wireless interactive toy construction elements disclosed herein. The toy con- struction system may include additional toy construction elements, including toy construction elements that do not perform any electronic functions, such as conventional toy construction elements.

Each toy construction element of the toy construction system and, in particular, each wireless interactive toy construction element, may comprise coupling members configured to engage coupling members of other toy construction elements of the toy construction system so as to detachably attach the toy construction elements to each other. To this end, the coupling members may utilize different coupling mechanisms, e.g. based on frictional engagement of the coupling members with each other, based on screws, plug-and-socket connections or other forms of mating engagements of cooperating coupling members.

Hence, toy construction elements that have been interconnected with each other by means of the coupling members can again be disconnected from each other such that they can be interconnected again with each other or with other toy construction elements of the system, e.g. so as to form a different spatial structure. In some embodiments, the toy construction elements are provided with a first and a second type of coupling members, such as coupling pegs and peg-receiving recesses for friction- ally engaging the pegs, or other pairs of mating or otherwise complementary coupling members configured to engage each other so as to form a physical connection. One type of coupling members may be located on one side, e.g. the top side, of the toy construction element while another, complementary type of coupling members may be located on an opposite side, e.g. the bottom side, of the toy construction element. In some embodiments, the toy construction elements include pegs extending from the top face of the toy construction element and corresponding peg-receiving cavities extending into the bottom face of the toy construction element for frictionally engaging the pegs by a suitable clamping force.

Generally, the toy construction system may impose limitations on the degrees of freedom of how the toy construction elements may be attached to each other, e.g. by limiting the possible relative positions and/or orientations at which they can be attached to each other. These limitations facilitate the detection of relative positions and/or orientations of electronic toy construction elements within a toy construction model. To this end, the coupling members may be positioned on grid points of a regular grid; in particular, the coupling members of the toy construction elements may be arranged such that the coupling members of a set of mutually interconnected toy construction elements are positioned on grid points of a three-dimensional regular grid. The dimensions of the toy construction elements may be defined as integer multiples of a unit length defined by the regular grid. It will be understood that a three-dimensional grid may be defined by a single unit length, by two unit lengths, e.g. one unit length applicable in two spatial dimensions while the other unit length is applicable in the third spatial dimension. Yet alternatively, the three-dimensional grid may define three unit lengths, one for each spatial dimension.

In some embodiments, the toy construction elements are made from plastics material, e.g. thermoplastic polymers, or from another suitable material. The toy construction elements may e.g. be made by an injection molding process or by another suitable manufacturing process.

Each wireless interactive toy construction element may comprise a housing. Each wireless interactive toy construction element may include a function device and/or a sensor system accommodated within said housing. Each wireless interactive toy construction element may include a processing unit accommodated within said housing. Each wireless interactive toy construction element may include the contactless sensor accommodated within said housing. Each wireless interactive toy construction element may include a position and/or orientation sensor device and/or a wireless communications interface accommodated within said housing. Each wireless interactive toy construction element may include a power source, e.g. a battery, in particular a rechargeable battery accommodated within said housing. The housing may be box-shaped or have a different suitable shape. The housing may define a top face and a bottom face, opposite the top face. At least some of the coupling members may extend from the top face. The housing may further comprise one or more side faces extending between the top and bottom faces. In some embodiments all wireless interactive toy construction elements are configured to be interchangeably and detachably connectable to other toy construction elements of the toy construction system. It will be appreciated, however, that embodiments of the various aspects disclosed herein may be applied to other types of electronic devices, in particular systems of individually movable electronic devices that perform contactless sensing operations.

Embodiments of the system described herein provide a distributed control for coordinating the contactless sensing operations. The distributed control requires minimal or even no user-configuration, is robust, reliable and yet efficient.

BRIEF DESCRIPTION OF THE DRAWINGS

Embodiments of the various aspects disclosed herein will be described in more detail in connection with the appended drawings, in which

Fig. 1 shows an example of an electronic device in the form of a wireless interactive toy construction element;

Fig. 2 shows a schematic block diagram of an example of an electronic device formed as a wireless interactive toy construction element;

Fig. 3 shows a schematic block diagram of a wireless interactive toy construction element and a wireless tag element in the form of a tag construction element;

Fig. 4 schematically illustrates an interactive toy construction system;

Fig. 5 illustrates an example of a combined shared schedule;

Fig. 6 illustrates a flow diagram of a process performed by an embodiment of an electronic device.

DETAILED DESCRIPTION

Various aspects and embodiments of an interactive toy system comprising a plurality of interactive wireless toys will now be described with reference to toy construction elements in the form of bricks. In this particular and corresponding embodiments, the electronic devices are each formed as a respective wireless interactive toy construction element, which each has a housing that is generally shaped as an orthogonal polyhedron with flat side faces and having coupling members extending from its upper surface and a cavity extending into its bottom surfaces. However other shapes and sizes of wireless interactive toy construction elements may be used, e.g. box-shaped or tile-shaped toy construction elements of different dimensions and with different numbers of coupling members. Moreover, while the brickshape has proven to be particularly useful, the various aspects disclosed herein may be applied to other forms of electronic devices, including other forms of toy construction elements for use in play applications educational applications, and/or the like.

FIG. 1 shows an example of an electronic device in the form of a wireless interactive toy construction element, generally designated 100. On the left-hand side of FIG. 1 the wireless interactive toy construction element is shown with its top surface visible and, on the right-hand side, the wireless interactive toy construction element is shown with its bottom side visible. In particular, the wireless interactive toy construction element comprises a generally box-shaped housing 101 with coupling pegs 104 extending from its top surface and with a cavity extending into the element from the bottom. The cavity is defined by side walls 102 and by a central, downwardly extending tube 103. The coupling pegs of another toy construction element can be received in the cavity in a frictional engagement, e.g. as disclosed in US 3 005 282. The construction elements shown in the remaining figures have this known type of coupling members in the form of cooperating pegs and cavities. However, other types of coupling members may also be used in addition to, or instead of, the pegs and cavities. The coupling pegs are arranged across the top surface in a square planar grid, i.e. defining orthogonal directions along which sequences of coupling pegs are arranged. The distance between neighboring coupling pegs is uniform and equal in both directions. This or similar arrangements of coupling members at coupling locations defining a regular planar grid allow the toy construction elements to be interconnected in a discrete number of positions and orientations relative two each other, in particular at right angles with respect to each other. In an assembled toy construction model, the coupling members of multiple toy construction elements may thus be located on grid points of a three-dimensional grid defined relative to the toy construction model.

In some embodiments, the housing 101 of the wireless interactive toy construction element is made from plastics material, e.g. thermoplastic polymers, or from another suitable material. The housing may e.g. be made by an injection molding process or by another suitable manufacturing process. The wireless interactive toy construction element 100 comprises one or more function devices 105 and a sensor system 108 comprising one or more sensors and/or sensor devices accommodated within the housing 101 of the wireless interactive toy construction element.

Generally, a function device may be any suitable device for performing a function, such as a function that provides a user-perceptible effect, such as a visible and/or audible effect. Examples of function devices may include any suitable mechanical and/or electrical device, arrangement, and/or circuitry adapted to perform one or more mechanical and/or electrical functions.

Examples of a mechanical function include driving a rotatable output shaft, winding- up a string or a chain which enables pulling an object closer to a toy module, moving a hinged part of the wireless interactive toy construction element, etc. The mechanical function may thus enable opening or closing a door, ejecting an object, rotating a turntable, moving a linear actuator, etc. Such mechanical motions can be driven by an electric motor.

Examples of an electrical function include emitting constant or blinking light, activating several lamps in a predetermined sequence, emitting audible sound such as beep, alarm, bell, siren, voice message, music, synthetic sound, natural or imitated sound simulating and/or stimulating play activities, playback of a sound, and/or other audio content, etc.

Accordingly, the function device may be selected from a motor, a light source (e.g. one or more LEDs) and a sound source (e.g. a loudspeaker). In some embodiments the system include different types of wireless interactive toy construction elements comprising respective, different types of function devices.

The sensor system 108 may include one or more sensors and/or sensor devices, e.g. including the contactless sensor and/or the position and/or orientation sensor device described herein and/or one or more other sensors, e.g. a linear or rotary encoder, a light detector, and a sound detector (e.g. a microphone), an accelerometer, and/or the like.

FIG. 2 shows a schematic block diagram of an example of an electronic device formed as a wireless interactive toy construction element, generally designated 100, e.g. of the wireless interactive toy construction element shown in FIG. 1.

The wireless interactive toy construction element 100 comprises a housing 101 defining a top face which is provided with coupling members 104, all as described above with reference to FIG.1. The wireless interactive toy construction element 100 further comprises, a processing unit 209 and one or more electromagnetic coils 207, all accommodated with the housing 101. The wireless interactive toy construction element may further comprise, also accommodated with the housing 101 , one or more additional sensors 208 and/or one or more function devices 105, e.g. as described in connection with the sensor system and function device of the embodiment of FIG. 1 above. The wireless interactive toy construction element 100 further comprises a rechargeable battery 210 or other rechargeable power source, and a wireless communications interface 211 , also accommodated with the housing 101.

Each electromagnetic coil 207 defines a coil axis around which the electromagnetic coil extends. In this example, the electromagnetic coils 207 are arranged such that one coil is arranged with its coil axis extending out of the top face of the housing while another other coil is arranged with its coil axis extending out of one of the side faces of the housing. A third electromagnetic coil may be arranged with its coil axis extending out of another side face of the housing, e.g. such that the axes of all three coils are oriented orthogonal to each other. In this manner, the wireless interactive toy construction element may use the electromagnetic coils to detect position and/or orientation coordinates of another wireless interactive toy construction element having similar arrangements of electromagnetic coils. Similarly, the wireless interactive toy may use one or more of the electromagnetic coils to detect, identify and/or capture data from a wireless tag. It will be appreciated, however, that other arrangements of coils are possible. Generally, the electromagnetic coils 207 may be operable as sensor probes for the contactless sensing operation described herein and/or as magnetic position and/or orientation sensor probes for magnetic position and/or orientation sensing operations described herein. The electromagnetic coils may further be operable to output interrogation signals and/or to emit magnetic probe signals as described herein. Yet further, the wireless interactive toy construction element may receive electrical energy via one or more of the electromagnetic coils 207 for charging the battery 210, which in turn powers the processing unit 209, the function device 105 and the wireless communications interface 211.

The one or more function devices 105 may include a light source, e.g. an LED, a loudspeaker, a motor, and/or another function device operable to perform a user- perceivable function.

The one or more sensors 208 may include a light sensor, a sound sensor, a rotational encoder, an accelerometer, a gyro, and/or any other suitable sensor, e.g. as described in connection with the sensor system of FIG. 1.

The wireless communications interface 211 may comprise a radio-frequency transceiver and an associated antenna. In some embodiments, the wireless communications interface may comprise a Bluetooth chip or circuit or another form of radio-frequency transceiver adapted for communication via a wireless communications network, e.g. using known low-power, short-range wireless networking technology, such as Bluetooth/Bluetooth Low Energy, ZigBee, Z-Wave, or a similar wireless technology for low-power personal area data networking in compliance with a standardized protocol. The wireless communications interface 211 may be operable for two-way communication with other wireless interactive toy construction elements of the system. Accordingly, the wireless interactive toy construction element may be operable to communicate its identity and/or operational characteristics, scheduling information, position information and/or the like.

The processing unit 209 may comprise one or more microcontrollers, one or more microprocessors, one or more ASICs, and/or one or more other suitable processing units, or combinations thereof and be configured to control the functional behavior of the wireless interactive toy construction element. The wireless interactive toy construction elements may be provided, e.g. pre-programmed, with a default behaviour, e.g. with default executable instructions stored in a memory of the wireless interactive toy construction element and executable by a processing unit of the wireless interactive toy construction element. The default executable instructions may define a set of predetermined rules for reacting to external stimuli as sensed by the one or more sensors 208 and/or by the electromagnetic coils 207. In some embodiments, the behaviour of the wireless interactive toy construction elements may be programmed or configured by the user, e.g. by receiving program data and/or configuration parameters. To this end, the wireless interactive toy construction element may receive program and/or control data and/or configuration parameters from a computer or from another external electronic device, e.g. directly or via another toy module of the system. An external electronic device may e.g. a desktop computer, a tablet computer, a smartphone, a laptop computer, or another programmable computing device. Alternatively or additionally, the wireless interactive toy construction element may capture program and/or control data and/or configuration parameters from a wireless tag, e.g. from an RFID tag, or from other data storage devices. For example, the wireless interactive toy construction element may be operable to read out such wireless tag or other data storage device in a contactless manner as described herein.

FIG. 3 shows a schematic block diagram of the wireless interactive toy construction element 100 of FIG. 2 and a tag construction element 400.

The tag construction element 400 is formed as a toy construction element with a housing 401 and coupling members 104 that allow the tag construction element 400 to be detachably connected to the wireless interactive toy construction element 100, e.g. as illustrated in FIG. 3. The housing 401 may be made of plastics material, e.g. as described in connection with FIG. 1. The tag construction element 400 and the wireless interactive toy construction element 100 may alternatively or additionally be connected to other toy construction elements of the toy construction system.

The tag construction element 400 may be a conventional toy construction element except that it is provided with a wireless tag, e.g. a known type of wireless tag, such as an RFID tag. Accordingly, the tag construction element 400 may comprise an an- tenna 407, e.g. a coil antenna, and associated processing circuitry 409. The processing circuitry 409 may comprise power harvesting circuitry for harvesting power from a received interrogation signal, signal demodulation and modulation circuitry and control logic and memory for creating a response signal to a received interrogation signal.

The tag construction element thus differs from a wireless interactive toy construction element that it does not include its own battery or other power source but is dependent on being energized by an interrogation signal from the wireless toy construction element 100. The tag construction element 400 further differs from the wireless interactive toy construction element 100 in that it lacks the capability to sense the presence of other wireless tag, that it lacks the capability of performing position and orientation sensing and that it lacks a wireless communications interface to a wireless communications network.

The wireless toy construction element 100 is configured to generate an interrogation signal, output the generated interrogation signal via one or more of its electromagnetic coils 207, and to receive a response signal from the tag construction element 400, also via one or more of the electromagnetic coils 207. Based on the received response signal, the processing unit 209 of the wireless interactive toy construction element 100 may detect the presence and, optionally, the identity of the tag construction element 400 when the tag construction element 400 is in a proximity of the wireless toy construction element 100, e.g. when the tag construction element 400 is physically attached to the wireless interactive toy construction element as illustrated in FIG.3, or when the tag construction element 400 is otherwise in close proximity to the wireless interactive toy construction element 100. The wireless interactive toy construction element 100 may further be configured to capture additional data, other than an identity of the tag construction element, from the tag construction element 400. The processing unit 209 of the wireless interactive toy construction element may then control the function device 105 responsive i.a. to the detected tag construction element and, optionally, further responsive to sensor signals obtained by one or more other sensors 208 of the wireless interactive toy construction element 100. It will be appreciated that the system may include multiple tag construction ele- merits. Accordingly, multiple tag construction elements may be attached to, or otherwise be brought into close proximity of, the wireless interactive toy construction element 100 at any point in time. Accordingly, the processing unit 209 of the wireless interactive toy construction element 100 may control the behavior of the wireless interactive toy construction element 100 responsive to one or more detected tag construction elements in its proximity. Moreover, the user may move the tag construction elements or the wireless interactive toy construction elements, such that one or more tag construction elements are no longer in sufficient proximity of the wireless interactive toy construction element for the wireless interactive toy construction element to be able to detect the tag construction element. Similarly, other tag construction elements may be brought into close proximity of the wireless interactive toy construction element such that they become detectable by the wireless interactive toy construction element. Accordingly, in order to be able to maintain an up-to-date inventory of tag construction elements currently being in close proximity of the wireless interactive toy construction element, the wireless interactive toy construction element 100 may frequently transmit interrogation signals and sense the corresponding response signals to maintain an up-to-date inventory of the tag construction elements that are currently in its proximity.

FIG. 4 schematically illustrates an interactive toy construction system. The system includes wireless interactive toy construction elements 100A-D, e.g. wireless interactive toy construction elements as described in connection with FIGs. 1 and 2. The system further comprises tag construction elements 400A-C, e.g. tag construction elements as described in connection with FIG. 3.

Each of the wireless interactive toy construction elements 100A-D is operable to perform contactless sensing operations to detect and acquire data from any tag construction element or elements positioned close enough to the interactive toy construction element to be within the tag sensing range of the respective wireless interactive toy construction element. The wireless interactive toy construction elements 100A-D are further operable to communicate with each other via a wireless communications network, e.g. by broadcasting messages to all other wireless interactive toy construction elements of the system or otherwise.

The wireless interactive toy construction elements 100A-D are further operable to perform mutual relative position and orientation measurements. To this end, at predetermined times, respective wireless interactive toy construction elements activate their one or more electromagnetic coils to emit a magnetic probe signal. The remaining wireless interactive toy construction elements use their respective electromagnetic coils to receive and sense the emitted probe signal and to perform magnetic field measurements. Based on the measured magnetic fields, the receiving wireless interactive toy construction elements may compute their own distance from the currently emitting wireless interactive toy construction element. They may optionally even determine their relative position and orientation relative to the emitting wireless interactive toy construction element. To this end, the wireless interactive toy construction elements may use any suitable magnetic positioning method, e.g. as described in W. Kim, J. Song and F. C. Park, "Closed-Form Position and Orientation Estimation for a Three-Axis Electromagnetic Tracking System," in IEEE Transactions on Industrial Electronics, vol. 65, no. 5, pp. 4331-4337, May 2018, doi: 10.1109/TIE.2017.2760244, or otherwise. It will be appreciated that a three-dimensional positioning may require that each wireless interactive toy element includes three coils that are preferably arranged orthogonally relative to each other. The wireless interactive toy construction elements may broadcast their determined distances and, optionally, additional relative directional position information and/or their relative orientations via the wireless communications network to the remaining wireless interactive toy construction elements, including the currently emitting wireless interactive toy construction element. The role of the emitting wireless toy construction element may selectively be assigned to respective ones of the wireless interactive toy construction elements, e.g. cyclically or according to another emission schedule. The emission schedule may be created by a selected one of the wireless interactive toy construction elements, also referred as the scheduler device. The scheduler device may broadcast the created emission schedule to the other wireless interactive toy construction elements or share the created schedule with the other wireless interactive toy construction elements in another manner. Accordingly, after a number of wireless interactive toy construction elements gave emitted respective probe signals, the wireless interactive toy construction elements are capable of obtaining distance and, optionally even directional position and/or orientation information relative to some, if not all, of the other wireless interactive toy construction elements of the system.

It will be appreciated that, alternatively or additionally to the magnetic position and/or orientation determination described above, the wireless interactive toy construction elements may use other methods of obtaining distance information relative to the other wireless interactive toy construction elements. For example, they may use a receive signal strength indicator of the wireless communication via the wireless communications network to estimate the distances to the respective other wireless interactive toy construction elements.

The magnetic position and/or orientation sensing operations may interfere with the tag sensing operations of the individual wireless interactive toy construction elements. Moreover, concurrent tag sensing operations of multiple wireless interactive toy construction elements may also interfere with each other if the wireless interactive toy construction elements are within an effective interference range of the tag sensing operation. Yet further, in order to keep, the size and cost of the wireless interactive toy construction elements small, it may be beneficial that each wireless interactive toy construction element uses at least in part the same electromagnetic coils and/or other hardware components for both tag sensing and position/orienta- tion sensing.

Accordingly, the wireless interactive toy construction elements preferably share a schedule of reserved times. The shared schedule may assign reserved times to respective wireless interactive toy construction elements. Each wireless interactive toy construction element may then perform scheduled tag sensing operations during the reserved times assigned to said wireless interactive toy construction element. The schedule of reserved times for scheduled tag sensing may also be created by the scheduler device that creates the emission schedule for the position and/or orientation sensing operations. Preferably, the scheduler device creates a combined shared schedule including both the emission times for the position and/or orientation sensing operations and the reserved times of the respective wireless interactive toy construction elements where they are allowed to perform scheduled tag sensing.

FIG. 5 illustrates an example of such a combined shared schedule. The shared schedule of FIG. 5 is an example of a schedule for scheduling tag sensing operations as well as position and/or orientation sensing operations of a system of electronic devices, e.g. of the wireless interactive toy construction system of FIG. 4. The example schedule of FIG. 5 is a schedule for four electronic devices. It will be appreciated, however, that other examples of schedules may be created for a different number of electronic devices. In the example of FIG. 5, each electronic device has an identifier associated with it, in this example “0”,... ,”3”. The shared schedule covers a predetermined period of time, in some examples the period of time may be between one or several tenths of seconds and several seconds. The schedule may correspond to a number of individual time slots, e.g. between 200 and 3000 time slots, or otherwise. However, it will be appreciated that schedules of different length may be used and/or schedules where the time slots have a different duration. The shared schedule may be used in a cyclic manner by repeating the schedule multiple times, e.g. until a new shared schedule has been created and distributed to the electronic devices. Alternatively, new schedules may be created and distributed such that a new schedule is used by the electronic devices each time a current schedule has been completed. Creating new schedules may allow the system to adapt the schedule to new situations, e.g. to electronic devices being turned OFF or otherwise leaving the wireless communication network, or to new electronic devices joining the wireless communications network, or by a change in the needed rate of tag sensing operations of one or more of the electronic devices. For the purpose of executing the schedule, the electronic devices may perform a suitable synchronization scheme, e.g. using broadcast signals of the wireless communications network. The shared schedule assigns reserved times as reserved time intervals for respective operations. It will be appreciated that a reserved time may be an individual time slot or a sequence of consecutive individual times slots, i.e. in some embodiments, a reserved time may have a duration defined as an integer multiple of the duration of the individual time slots.

The shared schedule reserves position and/or orientation sensing times 161 and assigns a probe signal emitter role to a respective electronic device for each of the reserved position and/or orientation sensing times 161. During a reserved position and/or orientation sensing time 161 , the electronic device designated as probe signal emitter emits a magnetic probe signal to allow the remaining electronic devices to perform position and/or orientation sensing operations of their respective posi- tions/orientations relative to the currently emitting electronic device, e.g. as described in connection with FIG. 4. Accordingly, the position and/or orientation sensing times are times reserved for cooperative magnetic sensing operations, i.e. magnetic sensing operations which involve a synchronized and concurrent operation of more than one, in particular all, electronic devices of the system. The times reserved for cooperative sensing operations thus serve to synchronize these operations and to assign different roles, in particular the probe signal emitter role and the probe signal receiver roles, to the respective electronic devices. In some embodiments, the duration of the position and/or orientation sensing times may be selected long enough to allow the probe signal receiving electronic devices to perform the magnetic field measurements. In some embodiments the duration of the position and/or orientation sensing times are between 5 ms and 20 ms, such as about 10 ms. The position and/or orientation sensing times may be grouped such that they are assigned as a sequence of consecutive time intervals, during which respective electronic devices are designated as probe signal emitters, so as to allow different electronic devices to act as probe signal emitters and allow for an improved overall determination of the spatial configuration of the electronic devices. The position and/or orientation sensing times, or groups thereof, may be sufficiently spaced apart to allow for reserved times for individual sensing operations, in particular tag sensing operations, to be allocated between them.

The shared schedule further reserves tag sensing times 162 to respective individual electronic devices. During a reserved tag sensing time, the electronic device to which the specific tag sensing time is assigned, may perform schedules tag sensing operations to detect and/or identify and/or capture data from any wireless tags in its proximity. The tag sensing times are reserved time slots for individual magnetic sensing operations, i.e. magnetic sensing operations performed by an individual electronic device without interaction with the other electronic devices, in particular without the other electronic devices participating or contributing to the individual magnetic sensing operation. In many situations, the other electronic devices would risk to interfere with the individual magnetic sensing operation of another electronic device were they to concurrently emit a probe or interrogation signal. Accordingly, at least in some embodiments and as illustrated in the example of FIG. 5, the reserved tag sensing times 162 for the individual magnetic sensing operations are reserved to individual electronic devices. Moreover, at least in embodiments where the electronic devices use the same electromagnetic coils and/or other components system resources for both the cooperative magnetic sensing operation and the individual magnetic sensing operations, the electronic devices may not be capable of performing both operations simultaneously. Accordingly, in some embodiments, the shared schedule assigns mutually non-overlapping and mutually exclusive time slots for the individual magnetic sensing operations and the individual magnetic sensing operations. In the example of FIG. 5, the wireless tag sensing operations are the only type of individual magnetic sensing operation, and the position and/or orientation sensing operations are the only type of cooperative magnetic sensing operation. It will be appreciated, however, that other embodiments may include reserved times for different respective types of individual magnetic sensing operations and/or for different respective types of cooperative magnetic sensing operations. Yet further, it will be appreciated, that other embodiments may include reserved times for other operations, in particular other operations that might interfere with the contactless sensing operations, such as other contactless sensing operations, other than magnetic sensor operations. Such other types of operations may include individual sensing operations and/or cooperative sensing operations.

It will further be appreciated that the shared schedule may include alternative or additional times, e.g. for alternative or additional operations. It will further be appreciated that the shared schedule may be created in a variety of ways, e.g. as a static schedule or dynamically, e.g. adaptively depending on the specific situation. The length of the reserved times for the individual sensing operations may depend on the time required to perform the individual sensing operation, For example, in the context of tag sensing operations, a duration of between 60 ms and 100 ms, such as about 80 ms, has been found to allow the electronic device, which performs the tag sensing, to either obtain an inventory of tag elements in its proximity, i.e. to detect and identify all readable wireless tag elements in its proximity, or to capture data from one of the identified wireless tag elements. Accordingly, if the electronic device has detected a new wireless tag element in its proximity, from which the electronic device has not yet captured any data, the electronic device may select to use a subsequent reserved time slot (or an additional time slot as described below) to capture the data from the newly discovered wireless tag element.

It will be appreciated that the rate at which the respective electronic devices can perform the individual magnetic sensing operations depends on a variety of factors, including the number of electronic devices in the system and the duration of the various magnetic sensing operations. The current number of electronic devices may e.g. be determined by the number of devices having joined the wireless communications network. In embodiments where electronic devices may join and leave the wireless communications network dynamically, the number of participating electronic devices, which need to be taken into account for the purpose of scheduling, may thus vary. When the individual magnetic sensing operation comprises tag sensing operations, and when multiple wireless tag elements may concurrently be within a detection range of an electronic device, the time required for the individual magnetic sensing operation may be relatively long compared to e.g. the cooperative position and/or orientation sensing operation, thereby effectively reducing the rate at which the individual electronic devices can perform the tag sensing operations. When the tag sensing rate becomes too low, the user may experience an undesired delay when interacting with the system. For example, when the user positions an electronic device in a proximity of a wireless tag element, it is desirable that the electronic device reacts to the detection of the wireless tag element in a user-perceptible manner without, or with only little, perceptible delay. In some embodiments, it may be desirable that the repetition rate of the tag sensing operation of an electronic device is at least 4 Hz, such as at least 8 Hz. Generally, in order to increase the rate at which the electronic devices can perform individual contactless (e.g. magnetic) sensing operations, in particular tag sensing operations, each electronic device may determine whether it may perform additional unscheduled individual contactless sensing operations during a reserved time slot, which is reserved for another electronic device, without the risk of unduly interfering with a scheduled individual magnetic sensing operation of said another electronic device.

FIG. 6 illustrates a flow diagram of a process performed by an embodiment of an electronic device, e.g. by electronic device 100A of the system of FIG. 4. In particular, the processing unit of the electronic device may perform the steps of the method and/or control one or more other components to perform the steps of the method.

In step S1 , the electronic device obtains a shared schedule, e.g. by receiving the shared schedule from another electronic device of the system or by itself creating the scheduled and distributing the schedule to the other electronic devices of the system.

In step S2, the electronic device determines whether the current time is reserved for a cooperative contactless sensing operation, for its own individual contactless sensing operation or for an individual contactless sensing operation of another one of the electronic devices. The contactless sensing operations may be magnetic sensing operations as described herein or other types of contactless sensing operations.

In step S3, when the current time is reserved for a cooperative contactless sensing operation, the electronic device performs the cooperative sensing operation. When the cooperative sensing operation is a position and/or orientation sensing operation, the electronic device obtains at least distance information and preferably additional position and/or orientation information relative to one or more of the other electronic devices. In particular, if the shared schedule designates said electronic device as a probe signal emitter during the current time, the electronic device emits a probe signal and receives position and/or orientation information from the other electronic devices based on the measurements performed by said other electronic devices during the current time slot and based on the emitted probe signal; otherwise, the electronic device detects the probe signal emitted by another electronic device, in particular for measuring one or more magnetic field components. The electronic device then determines its own position and/or orientation relative to the currently emitting electronic device and broadcasts its determined position and/or orientation information to the other electronic devices. The process proceeds at step S8.

In step S4, when the current time is reserved for the electronic device to perform its individual contactless sensing operation, the electronic device performs the scheduled individual contactless sensing operation, e.g. performs tag sensing, and proceeds at step S8.

In step S5, when the current time is reserved for another electronic device to perform individual sensing operation by said another electronic device, the electronic device optionally determines whether it has a need of additional, unscheduled individual contactless sensing operations, in addition to the scheduled individual sensing operations performed during times reserved for it. In some embodiments, the electronic device may always attempt to perform additional, unscheduled individual sensing contactless operations while, in other embodiments, the electronic device may make a dynamic determination. Such a dynamic determination may e.g. be based on the amount of time until the next available time that is reserved for the electronic device. For example, if the amount of time is longer than a threshold duration, the electronic device may determine that there is a need for an additional, unscheduled individual contactless sensing operation. Other factors that may be used by the electronic device for making that determination include, the number of wireless tag elements the electronic device has recently detected, a recently determined rate of change of the number of wireless tag elements, the type of play interaction process currently executed by the electronic device, and/or other factors. If the electronic device determines that no additional, unscheduled individual contactless sensing operation is needed, the process proceeds at step S8; otherwise the process proceeds at step S6 and attempts to perform an additional, unscheduled individual contactless sensing operation. At step S6, the electronic device determines which other electronic device the current time is reserved for, and the electronic device determines whether it has distance information available about the distance between itself and the other electronic device, which has the current reserved time assigned to it. If the electronic device has no, or not sufficiently reliable, distance information available or if the distance to the other electronic device is smaller than a threshold distance, the process determines that there is a risk of interference and proceeds at step S8 without making any unscheduled individual contactless sensing operation. Otherwise, i.e. if the electronic device has distance information available that indicates the distance to the other electronic device to be larger than the threshold distance, the electronic device proceeds to step S7 and performs, or attempts to perform, an additional, unscheduled individual contactless sensing operation.

At step S7 the electronic device performs an unscheduled individual contactless sensing operation, optionally subject to a suitable interference avoidance process so as to reduce the risk of two electronic devices concurrently performing unscheduled individual contactless sensing operations.

In the example of FIG. 4, the threshold distance in respect of electronic device 100A is indicated by a dashed circle 150. Accordingly, if the current time is assigned to electronic device 100B, the electronic device 100A would refrain from performing an unscheduled individual contactless sensing operation at the current time. On the other hand, if the current time is assigned to electronic device 100C or 100D, the electronic device 100A may attempt to perform an unscheduled individual contactless sensing operation, optionally subject to an interference avoidance process to ensure (or at least to increase the likelihood) that e.g. electronic devices 100A and 100B do not both perform an individual sensing operation during the same time, e.g. during a time reserved for e.g. electronic device 100D. The threshold distance 150 may be selected to be larger than a determined or estimated interference range of the individual contactless sensing operations. The skilled person will appreciate that the interference range may be determined during manufacture by suitable measurements or test procedures. The larger the predetermined threshold distance, the less likely the electronic devices will be able to perform unscheduled individual contactless sensing operations. In the context of tag sensing operations, the threshold distance may e.g. be selected to be between 10 cm and 50 cm.

Again referring to FIG. 6, upon completion of the unscheduled individual contactless sensing operation at step S7, the process proceeds at step S8.

At step S8, responsive to the results of the cooperative contactless sensing operation (e.g. the position and/or orientation sensing operation) and/or responsive to the results of the individual contactless sensing (e.g. the tag sensing) operation, the electronic device optionally performs one or more functions, in particular one or more user-perceptible functions, e.g. by executing suitable programmed instructions implementing an interactive play experience. To this end, the electronic device may control its function device to perform a user-perceptible function.

At subsequent step S9, if there are further times in the current shared schedule, the process returns to step S2 and proceeds with the next time; otherwise, the process return to step S1 and obtains a new shared schedule.

Various aspects of the system have been described in the context of tag sensing operations and magnetic position and/or orientation sensing operations. However, it will be appreciated that the various aspects disclosed herein may also be applied to other contactless sensing operations that involve the risk of interference when performed by multiple electronic devices concurrently and in close proximity of another. While the above examples have been described in the context of a system where all electronic devices perform the same type of individual contactless sensing operations, the various aspects disclosed herein may also be applied to embodiments where the electronic devices perform respective and different individual contactless sensing operations, in particular where the individual sensing operations involve the risk of interference with each other.

Various embodiments described herein may be summarized as follows: Embodiment 1 : A system comprising a plurality of electronic devices, wherein each electronic device comprises:

- a contactless sensor for performing contactless sensing operations, and

- a processing unit configured to control the contactless sensor to perform one or more scheduled contactless sensing operations according to a shared schedule, the shared schedule assigning reserved times to respective ones of the plurality of electronic devices, each reserved time being indicative of a time reserved for a selected one of the electronic devices to perform at least one scheduled contactless sensing operation, wherein the plurality of electronic devices comprises a first electronic device and a second electronic device, different from the first electronic device, wherein the shared schedule includes a first reserved time, reserved for the first electronic device, wherein the processing unit of the second electronic device is further configured to:

Embodiment 2: A system comprising a plurality of electronic devices, wherein each electronic device comprises:

- a contactless sensor for performing contactless sensing operations, and

Embodiment 3: The system according to embodiment 1 or 2, wherein the system is an interactive toy system and each of the electronic devices is a wireless interactive toy.

Embodiment 4: The system according to embodiment 3, wherein the interactive toy system is an interactive toy construction system and each wireless interactive toy is or comprises a wireless interactive toy construction element.

Embodiment 5: The system according to any one of the preceding embodiments; wherein some or all of the contactless sensing operations comprise an automatic identification and/or data capture operation, in particular a wireless tag sensing operation.

Embodiment 6: The system according to any one of the preceding embodiments, wherein each electronic device comprises a magnetic position and/or orientation sensor device configured to perform one or more magnetic position and/or orientation sensing operations for determining relative positions and/or relative orientation of respective ones of the electronic devices.

Embodiment 7: The system according to embodiment 5, wherein the second electronic device is configured to obtain the distance information at least by performing said magnetic position sensing operation. Embodiment 8: The system according to any one of the preceding embodiments, wherein each electronic device comprises a wireless communications interface configured for wireless communication via a wireless communications network and wherein the electronic devices are configured to wirelessly communicate with each other via said wireless communications network.

Embodiment 9: The system according to embodiment 8, wherein the processing unit of the second electronic device is configured to obtain the distance information at least based on a communication signal received by the wireless communications interface of the second electronic device from the first electronic device via said wireless communications network, in particular by determining a received signal strength indicator associated with said received communications signal.

Embodiment 10: The system according to embodiment 8 or 9, wherein the plurality of devices are configured to share the shared schedule via said wireless communications network.

Embodiment 11 : The system according to any one of the preceding embodiments, wherein the processing unit of the second electronic device is configured to, when the obtained distance is larger than the threshold distance:

- perform an interference avoidance process to eliminate or at least reduce a risk of a third electronic device of the plurality of electronic devices, different from the first electronic device, performing an unscheduled contactless sensing operation at the first reserved time, and

- control the contactless sensor of the second electronic device to perform the unscheduled contactless sensing operation at the first reserved time conditioned on a result of the performed interference avoidance process.

Embodiment 12: An electronic device for use in a system of electronic devices, wherein the electronic device comprises:

- a contactless sensor for perform contactless sensing operations, and

- a processing unit configured to control the contactless sensor to perform one or more scheduled contactless sensing operations according to a shared schedule, the shared schedule assigning access times to respective ones of the plurality of electronic devices, each access time being indicative of a time reserved for a selected one of the electronic devices to perform the contactless sensing operation; wherein the processing unit is further configured to: - obtain distance information about a distance between the electronic device and another electronic device of the plurality of electronic devices; and

Claims

1 . A system comprising a plurality of electronic devices, the plurality of electronic devices comprising a first electronic device and a second electronic device, different from the first electronic device, wherein each electronic device of the plurality of electronic devices comprises: a contactless sensor for performing contactless sensing operations, and a processing unit, wherein the processing unit of the second electronic device of the plurality of electronic devices is configured to:

- perform an interference avoidance process to at least reduce the risk of another electronic device of the plurality of electronic devices, different from the second electronic device, performing an interfering contactless sensing operation concurrently with the second electronic device, and

2. The system according to claim 1 , wherein the processing unit of each electronic device is configured to control the contactless sensor to perform one or more scheduled contactless sensing operations according to a shared schedule, the shared schedule assigning reserved times to respective ones of the plurality of electronic devices, each reserved time being indicative of a time reserved for a selected one of the electronic devices to perform at least one scheduled contactless sensing operation, wherein the shared schedule includes a first reserved time, reserved for the first electronic device, wherein the processing unit of the second electronic device is further configured to: - obtain a risk measure indicative of a risk of interference between respective contactless sensing operations performed by the first electronic device and the second electronic device; and

3. The system according to claim 2, wherein the risk measure includes distance information about a distance between the first electronic device and the second electronic device, wherein a threshold distance is indicative of the threshold risk, and wherein the processing unit of the second electronic device is configured to:

- control the contactless sensor of the second electronic device to perform at least one unscheduled contactless sensing operation at the first reserved time when the obtained distance is larger than the threshold distance.

4. The system according to any one of the preceding claims, wherein the system is an interactive toy system and each of the electronic devices is a wireless interactive toy.

5. The system according to claim 4, wherein the interactive toy system is an interactive toy construction system, and each wireless interactive toy is or comprises a wireless interactive toy construction element.

6. The system according to any one of the preceding claims; wherein some or all of the contactless sensing operations comprise an automatic identification and/or data capture operation, in particular a wireless tag sensing operation.

7. The system according to any one of the preceding claims, wherein each electronic device comprises a magnetic position and/or orientation sensor device configured to perform one or more magnetic position and/or orientation sensing operations for determining relative positions and/or relative orientation of respective ones of the electronic devices.

8. The system according to claim 7, when directly or indirectly dependent on claim 3, wherein the second electronic device is configured to obtain the distance information at least by performing said magnetic position sensing operation.

9. The system according to any one of the preceding claims, wherein each electronic device comprises a wireless communications interface configured for wireless communication via a wireless communications network and wherein the electronic devices are configured to wirelessly communicate with each other via said wireless communications network.

10. The system according to claim 9, when directly or indirectly dependent on claim 3, wherein the processing unit of the second electronic device is configured to obtain the distance information at least based on a communication signal received by the wireless communications interface of the second electronic device from the first electronic device via said wireless communications network, in particular by determining a received signal strength indicator associated with said received communications signal.

11. The system according to claim 9 or 10, wherein the plurality of devices are configured to share the shared schedule via said wireless communications network.

12. The system according to any one of the preceding claims, when directly or indirectly dependent on claim 3, wherein the processing unit of the second electronic device is configured to, when the obtained distance is larger than the threshold distance:

13. An electronic device for use in a system of electronic devices, wherein the electronic device comprises:

- a contactless sensor for performing contactless sensing operations, and

- a processing unit, wherein the processing unit is configured to:

- control the contactless sensor of the electronic device to perform the contactless sensing operation conditioned on a risk of another electronic device performing a concurrent interfering contactless sensing operation being smaller than a threshold risk.

14. The electronic device according to claim 13, wherein the processing unit is configured to control the contactless sensor to perform one or more scheduled contactless sensing operations according to a shared schedule, the shared schedule assigning access times to respective ones of the plurality of electronic devices, each access time being indicative of a time reserved for a selected one of the electronic devices to perform the contactless sensing operation; wherein the processing unit is further configured to:

15. The electronic device according to claim 14, wherein the risk measure includes distance information about a distance between the first electronic device and the second electronic device, wherein a threshold distance is indicative of the threshold risk, and wherein the processing unit is configured to:

- obtain distance information about a distance between the electronic device and another electronic device of the plurality of electronic devices; and - control, when the obtained distance is larger than a threshold distance, the contactless sensor to perform at least one unscheduled sensing operation during one of the reserved times, said one of the reserved times being reserved for said another electronic device.