FR3151815A1 - METHOD FOR PROJECTING SAFETY INFORMATION ON THE TRAJECTORY OF A MOBILE CHARGING ROBOT FOR ELECTRIFIED VEHICLES - Google Patents

Abstract

The method is implemented in a mobile robot (RRI) for charging an electrified vehicle (EV). According to the invention, it comprises the steps of: a) detecting actual parking of the vehicle in a location included in an action zone (ZA), b) acquiring trajectory information (TRA) spatially defining in a map of the action zone a trajectory to be accomplished by the robot between its actual location and the location of a charge reception system (SCR) of the vehicle, c) constructing, from the trajectory information, a graphic image of a light pattern (PAb) representative of the trajectory, and d) projecting the constructed image onto the ground so as to represent, for the benefit of a person present on the premises, the trajectory of the mobile robot by means of the light pattern forming said safety information. Figure 2

Description

METHOD FOR PROJECTING SAFETY INFORMATION ON THE TRAJECTORY OF A MOBILE CHARGING ROBOT FOR ELECTRIFIED VEHICLES

The present invention relates generally to the field of mobile charging robots for electric traction storage devices of electrified vehicles. More particularly, the invention relates to a method for projecting safety information on the trajectory of movement of a mobile charging robot for electrified vehicles. The invention also relates to a mobile charging robot, such as a mobile electromagnetic induction charging robot, for implementing the aforementioned method.

Charging the electric traction storage devices of electrified vehicles, whether fully electric or hybrid, in a conventional electric charging station is a tedious task for the user. The user must park in the immediate vicinity of the charging station and connect the vehicle to it using an electrical connection cable. The user must manually manage the insertion of male and female electrical sockets and the unwinding/winding of the electrical connection cable.

The electromagnetic induction mobile charging robot is designed to automate the electrical charging process, while minimizing any user input. Electromagnetic induction, by allowing contactless transfer of electrical energy, simplifies the electrical charging process, in particular by eliminating the need for plugs to be plugged in. In addition, the mobility of the robot provides flexibility for the vehicle parking location for the charging operation. When a vehicle is detected, the robot, equipped with a primary charging coil, moves and positions itself under the vehicle, facing the vehicle's secondary charging coil, so as to perform the charging operation. In the mobile robot, the primary charging coil is supplied with energy by an electrical power cable served by a motorized device automatically managing the winding/unwinding operations of the latter. The ability of the mobile robot to reach the secondary charging coil of the vehicle at the location where the vehicle is parked may be limited by the available length of the power supply cable, as well as by obstacles and architectural elements such as walls and pillars, or the like. Thus, in certain situations, given the parking location chosen by the user and the aforementioned constraints, the mobile robot may be unable to perform the vehicle charging operation.

To address the above problem, the applicant proposed, in its unpublished French patent application FR2304729 filed on May 12, 2023, a method for assisting in parking an electrified vehicle by projecting a light pattern onto the ground indicating an area accessible to a mobile charging robot by electromagnetic induction.

Furthermore, from document DE102018201441A1, a mobile charging station is known which can be moved and arranged at a suitable location. This charging station comprises a light projection device to indicate to the user a suitable parking location. Furthermore, from document WO201433094A1, a device is known designed to provide a service to a vehicle, such as recharging an electric battery, which moves autonomously, by detecting and avoiding obstacles present in its path.

In this context of recharging an electrified vehicle by a mobile robot, the inventive entity has identified the existence of a possible safety risk for people when the robot moves towards the parked vehicle to carry out its charging mission. A person present in the area of action of the mobile robot may be surprised by an unanticipated movement of the robot and suffer injuries due to a fall due to loss of balance or a collision with the robot. In addition, objects may be deposited by people in the path of the robot, which may complicate the robot's task of reaching the vehicle, or even prevent it from reaching the vehicle and carrying out its charging mission.

The present invention aims to provide a method for projecting safety information of the movement trajectory of a mobile charging robot for electrified vehicles. The projected trajectory information shows the movement intentions of the mobile robot to people present on the scene.

According to a first aspect, the invention relates to a method for projecting safety information on a travel trajectory implemented in a mobile robot for charging an electrified vehicle. According to the invention, the method comprises the steps of a) detecting actual parking of the electrified vehicle in a location included in an action zone of the mobile robot, b) acquiring trajectory information spatially defining in a map of the action zone a trajectory to be accomplished by the mobile robot between its actual location and the location of a charging reception system of the electrified vehicle, c) constructing, from the trajectory information, a graphic image of a light pattern representative of the trajectory to be accomplished by the mobile robot, and d) projecting the graphic image onto the ground so as to represent, for the benefit of a person present on the premises, the trajectory of the mobile robot by means of the light pattern forming said safety information.

According to a particular embodiment of the method, when the latter is implemented with a trajectory to be accomplished by the mobile robot which comprises several sections to which confidence rates are attributed on the robustness of their calculation, step b) also comprises the acquisition of confidence rate information for the sections of the trajectory to be accomplished, and step c) comprises the construction of the graphic image of the light pattern also from the confidence rate information so as to represent the sections in the light pattern differently according to the confidence rates.

According to a particular characteristic, the sections are represented in the light pattern with different shapes, colors and/or lighting modes depending on the confidence rates.

According to another particular characteristic, the shapes include segments and/or points.

According to yet another particular feature, the lighting modes include a continuous lighting mode and/or a flashing lighting mode.

The invention also relates to a mobile robot for charging an electrified vehicle, the robot comprising an electric traction system, a navigation system, a wireless data communication module, a charging system, a control computer and a light projector, characterized in that the control computer comprises a memory storing program instructions for implementing the method as briefly described above.

According to a particular embodiment, the charging system of the mobile robot is an electromagnetic induction charging system.

Other advantages and characteristics of the present invention will appear more clearly on reading the detailed description below of several particular embodiments of the invention, with reference to the appended drawings, in which:

There is an illustration of an electromagnetic induction charging system for an electrified vehicle, including a projection on the ground of a light pattern showing a path of movement to be accomplished by a mobile charging robot to reach a wireless charging reception system of a parked vehicle.

There is another illustration of the electromagnetic induction charging system of the , showing another movement trajectory to be accomplished by a mobile charging robot to reach the wireless charging receiving system of the parked vehicle.

There is a block diagram showing the general architecture of a mobile electromagnetic induction charging robot for implementing the method of the invention.

There is a flowchart of a particular embodiment of the method of the invention.

In reference to the , there and the , a particular embodiment RRI of a mobile charging robot in which the method of the invention is implemented is now described as an example. In this exemplary embodiment, the mobile charging robot considered RRI is a mobile robot for charging by electromagnetic induction.

A motorized cable serving device DA is associated with the mobile robot RRI and automatically controls winding/unwinding operations of an electric power cable AL according to the movements of the mobile robot RRI. The electric power cable AL is connected to a power supply network and provides the mobile robot RRI with electrical energy for charging by electromagnetic induction.

The RRI mobile robot here mainly includes an electric traction system TE, a navigation system NAV, an electromagnetic induction charging system IND, a wireless communication module COM, a light projector PO and a control computer ECU.

The TE electric traction system allows autonomous movements of the RRI robot. The TE system comprises one or more WH drive wheels rotated by an ME electric motor and a DIR steering system, these means granting the RRI robot good maneuverability in its action zone.

The navigation system NAV controls the movements of the RRI robot. The NAV system typically comprises one or more detection devices SE of different technologies, such as scanners and laser ranging sensors, of the so-called “LiDAR” type for “Light Detection and Ranging” in English, and/or cameras. The information provided by the detection devices SE allows the NAV system to establish a map of the environment around the RRI robot. This map is used to identify an action zone ZA of the RRI robot and determine a parking zone for a detected electrified vehicle EV which is included in the aforementioned action zone ZA, as well as for the movements of the RRI robot.

The electromagnetic induction charging system IND essentially comprises a primary electromagnetic induction charging coil BP and an electrical converter (not shown). In the mobile robot RRI, the primary coil BP is arranged in an upper part thereof, so as to come opposite and as close as possible to a secondary electromagnetic induction charging coil of a wireless charging reception system SCR of the vehicle VE when the mobile robot RRI is placed under the vehicle VE to carry out charging. This wireless charging reception system SCR is a system called “WPT” by the person skilled in the art, for “Wireless Power Transfer” in English. During induction charging of the vehicle VE, the primary coil BP is powered by the aforementioned electrical converter which receives electrical energy via the electrical power supply cable AL.

The wireless communication module COM is typically a radio module that allows data exchanges between the VE vehicle and the RRI mobile robot. Thus, the COM radio module shares with a compatible radio communication module of the VE vehicle a data communication radio link LR, for example, of the “DSRC” type, for “Dedicated Short-Range Communication” in English, according to a protocol of the “V2X” type, for “vehicle-to-everything”. Thanks to this data communication radio link LR, the RRI mobile robot exchanges with the VE vehicle all the information necessary for managing the charging process, in particular here, underbody position information of the wireless charging reception system SCR which is transmitted by the VE vehicle to the RRI mobile robot.

The PO light projector is typically an LED or laser projector, with a control interface allowing control by computer.

In the invention, the PO projector has the function of projecting onto the ground a monochrome or polychrome light pattern, marked PAa at the and PAb at the , which materializes a calculated movement trajectory that the RRI mobile robot must follow to reach the SCR wireless charging reception system of the VE vehicle. The light pattern PAa, PAb, projected on the ground informs the people present on the premises of the movement intentions of the RRI mobile robot, so that they can adapt their behavior accordingly.

The light pattern PAa, PAb may be formed in particular of segments and/or points, with a continuous or flashing lighting mode. These segments and points may also have different colors. Particular meanings are attributed to the different shapes (segment, point or others) of the pattern PAa, PAb, to its colors and to its lighting modes. By granting different shapes, colors and/or lighting modes to the sections of the trajectory, it is thus possible to include additional information in the light pattern PAa, PAb. In this embodiment, in the case where different sections of the trajectory calculated by the mobile robot RRI do not have the same degree of robustness, the use of different shapes, colors and/or lighting modes makes it possible to distinguish in the light pattern PAa, PAb, the sections of the trajectory according to assigned confidence rates.

The mobile robot RRI is controlled by an embedded software system SW hosted in a memory MEM of the control computer ECU. The embedded software system SW comprises a software module ML dedicated to the implementation of the method of the invention. The execution of code instructions of the software module ML by the control computer ECU allows the implementation of the method of the invention for the projection of the light pattern PAa, PAb, materializing the trajectory that the mobile robot RRI must accomplish.

The method of the invention is implemented within the framework of a general process for managing the charging of an electrified vehicle EV by the mobile robot RRI. In this general process, the user of the EV vehicle is guided by the mobile robot RRI so that he parks his vehicle at an appropriate parking location in the action zone ZA of the mobile robot RRI. A guidance technology by projection on the ground of a light pattern indicating an appropriate parking location is described in the aforementioned unpublished French patent application FR2304729. The software module ML activates its processing process for implementing the method of the present invention after the user has parked the EV vehicle at the appropriate parking location.

Now also referring to the , the main steps S1 to S5 of the process of processing the software module ML in the control computer ECU are described above, for the implementation of a particular embodiment of the method of the invention.

Step S1 is the detection of the parking of the electrified vehicle VE at a suitable location to which the mobile robot RRI has access. The mobile robot RRI detects the finalized parking of the vehicle VE following a data exchange between them and/or by means of its detection devices SE and a digital image analysis. The detection of the parking of the vehicle VE activates the following processing process corresponding to steps S2 to S5.

In step S2, the processing process acquires trajectory information to be performed TRA (cf. ) and DC confidence rate information (cf. ) from another process executed by the ECU control computer. It will be noted that, in simpler embodiments of the method of the invention, the confidence rate information may not be taken into account by the processing process and, in this case, will therefore not be acquired as indicated above.

The acquisition of the trajectory information to be accomplished TRA and the confidence rate information DC is cyclical given that these are updated dynamically (typically, in real time or quasi-real time) as the mobile robot RRI moves. This cyclical acquisition of the TRA and DC information is schematically represented by the loop arrow B1 at .

The trajectory information to be accomplished TRA spatially defines, in the mapping of the action zone ZA, the trajectory to be accomplished calculated for the mobile robot RRI between its actual location at a given time and the location of the wireless charging reception system SCR of the vehicle VE. The trajectory to be accomplished is divided into several sections, such as those TR1a to TR4a and TR1b to TR5b schematically represented in the light pattern PAa of the and the PAb light pattern of the , respectively.

The DC confidence rate information is a confidence rate on the computational robustness assigned respectively to the different sections of the trajectory to be accomplished. Thus, in the trajectory examples shown in and the , confidence rates DC1a to DC4a and DC1b to DC5b are assigned to trajectory segments TR1a to TR4a and TR1b to TR5b, respectively. A trajectory segment with a high confidence rate is robust, meaning that the probability is low for this segment to be modified during the progression of the RRI mobile robot on its trajectory. On the other hand, a trajectory segment with a low confidence rate is likely to be modified during the progression of the RRI mobile robot on its trajectory.

The dispersion of confidence rates is essentially linked to a precision (image resolution) of the mapping which is not uniform depending on the considered area of it. When the RRI mobile robot progresses on its trajectory, the SE detection devices, by approaching certain areas or by having a better image capture angle, provide data with better precision, and the trajectory for certain sections remaining to be completed and having low confidence rates can be recalculated. This will give rise to a confirmation, a consolidation or a substantial modification of the sections concerned and to the attribution to them of higher confidence rates.

In step S3, the processing process dynamically defines (typically, in real time or quasi-real time) the light pattern PAa, PAb, to be projected on the ground, based on the TRA and DC information. This dynamic definition of the light pattern PAa, PAb, is schematically represented by the loop arrow B2 at .

In this step S3, the process processes the TRA information and extracts the different sections of the trajectory to be accomplished with their spatial coordinates CS. The confidence rates extracted from the DC information are used to define projection variables VP for each of the sections of the trajectory to be accomplished. In this exemplary embodiment, the projection variables VP include the shape (segment, point or others), the color and the illumination mode.

Step S4 is the construction of graphic images IM to be projected, namely, those of the light pattern PAa, PAb, from the data obtained in step S3 which are the spatial coordinate data CS and the projection variables VP.

Step S5 is the projection by the projector PO of the images IM of the light pattern PAa, PAb, constructed in step S4.

By providing a visualization on the ground of the path that the mobile charging robot will take, the invention provides an improvement in the level of safety during the movements of the mobile robot. People present on the premises are informed and adapt their behavior to avoid any risk of collision with the mobile robot.

The invention is not limited to the particular embodiments which have been described here by way of example. Those skilled in the art, depending on the applications of the invention, will be able to make various modifications and variations falling within the scope of protection of the invention.

Claims (7)

Method for projecting safety information on a travel trajectory implemented in a mobile charging robot (RRI) of an electrified vehicle (VE), characterized in that it comprises the steps of a) detecting (S1) effective parking of said electrified vehicle (VE) in a location included in an action zone (ZA) of said mobile robot (RRI), b) acquiring (S2) trajectory information (TRA) spatially defining in a map of said action zone (ZA) a trajectory to be accomplished by said mobile robot (RRI) between its effective location and the location of a charge reception system (SCR) of said electrified vehicle (VE), c) constructing (S3, S4), from said trajectory information (TRA), a graphic image (IM) of a light pattern (PAa, PAb) representative of said trajectory to be accomplished by said mobile robot (RRI), and d) projecting (S5) said graphic image (IM) onto the ground so as to represent, for the benefit of a person present on the ground, places, said trajectory by means of said light pattern (PAa, PAb) forming said security information. Method according to claim 1, implemented with a trajectory to be accomplished by said mobile robot (RRI) which comprises several sections (TR) to which confidence rates are attributed on the robustness of their calculation (DC), characterized in that said step b) also comprises the acquisition of confidence rate information (DC) for said sections (TR) of said trajectory to be accomplished, and said step c) comprises the construction of said graphic image (IM) of said light pattern (PAa, PAb) also from said confidence rate information (DC) so as to represent said sections (TR) differently in said light pattern (PAa, PAb) according to said confidence rates (DC). Method according to claim 2, characterized in that said sections (TR) are represented in said light pattern (PAa, PAb) with different shapes, colors and/or lighting modes depending on said confidence rates (DC). Method according to claim 3, characterized in that said shapes comprise segments and/or points. Method according to claim 3 or 4, characterized in that said lighting modes comprise a continuous lighting mode and/or a flashing lighting mode. Mobile robot for charging an electrified vehicle (EV), said robot (RRI) comprising an electric traction system (TE), a navigation system (NAV), a wireless data communication module (COM), a charging system (IND), a control computer (ECU) and a light projector (PO), characterized in that said control computer (ECU) comprises a memory (MEM) storing program instructions (ML) for implementing the method according to any one of claims 1 to 5. Mobile charging robot according to claim 6, characterized in that said charging system is an electromagnetic induction (IND) charging system.