WO2011099162A1 - Network system and base station - Google Patents

Abstract

In a system comprising a plurality of sensor nodes and a base station, a means by which the sensor nodes which operate intermittently do not consume extra electric power, and processing delay of the base station and data loss of the sensor nodes can be prevented, is provided. Each of the plurality of sensor nodes transmits acquired data at a predetermined interval on the basis of preset communication settings (for example, in IEEE802.15.4, a wireless channel, PANID, short address, etc.) On the other hand, the communicable sensor nodes and the communication settings for the sensor nodes have been previously recorded in the base station, and the communication settings are sequentially switched corresponding to the time assigned to the respective sensor nodes so as to communicate with the plurality of sensor nodes.

Description

Network system and base station

The present invention relates to a technology that can be worn on a person's body and that presents characteristics of life by presenting human behavior from information on a sensor terminal that measures biological information and behavioral states, and presents improvement means.

Small sensor nodes equipped with sensors, wireless devices, microcomputers, etc. are in the practical stage. This sensor node is activated only when sensing or wireless communication is necessary, and otherwise it is operated for a long time with a small internal battery, with a small diameter of 3cm, by turning off the power and reducing power consumption. Yes, it is easy for people to wear.

In Patent Document 1, even when a sensor node and a base station that receives data are separated from the communication range, they are recorded in a storage built in the sensor node, and transmitted together when the data returns to the communication range. Thus, a method for preventing data loss is disclosed. Further, the wireless standard IEEE 802.15.4 is known as a wireless communication means used for the sensor node. This standard is a wireless standard with low power consumption instead of suppressing transmission speed and communication distance. In addition, since the sensor node performs communication without specifying a base station, the base station to be communicated with can be switched by a communication process called a signal request to the neighboring base station and association.

Patent Document 2 discloses means for switching a communication partner by transmitting a signal for starting a sensor node as a communication partner from the base station side when a plurality of sensor nodes communicate with the base station.

JP 2007-184754 A JP 2005-324610 A

It is now possible for humans to wear ultra-compact sensor nodes to constantly measure human behavior information such as activities in human life and cycles of sleep. As shown in Patent Document 1, even if communication with a base station cannot be made temporarily, measurement data can be recorded in a built-in storage and transmitted collectively later. However, by collecting data measured in daily life through the network frequently throughout the day and notifying the analysis results to the person, family, doctors, etc., it can be applied to improve health and safety management and quality of life. In order to reduce the power consumption of the sensor node, it is necessary to install base stations at a plurality of main places where people live and collect data.

However, when the sensor node moves, in wireless communication according to the wireless standard IEEE802.15.4, the base station is searched for at the moving destination and the association process is performed. Therefore, reception of a reference signal (beacon) from the base station is awaited. The time is much longer than the reply (Ack) during normal data transmission. Therefore, more than 10 times more power is consumed for base station switching when moving compared to normal data transmission.

Also, in order to measure and record minute movements of a person, a sensing cycle of less than a second is required, so the amount of data to be transmitted becomes as large as 10 megabytes or more per day. Furthermore, if data while being temporarily away from the base station are transmitted together, a large amount of data is transmitted in a short time. For this reason, when the base station receives transmission data from a plurality of sensor nodes in a concentrated manner, in a communication band for low-speed wireless communication such as IEEE 802.15.4, a drastic reduction in communication speed due to congestion control, Data processing delays and data loss due to memory overflow may occur.

In Patent Document 2, it is possible to avoid the concentration of data reception processing by switching the communication partner, but since the sensor node side needs to wait in a state where it can always receive a control signal from the base station, intermittent operation is not possible. It is difficult and the power consumption of the sensor node cannot be reduced.

Of the inventions disclosed in this application, the outline of typical ones will be briefly described as follows.

A network system including a plurality of terminals and a base station that communicates with each of the plurality of terminals. Each of the plurality of terminals transmits biometric information to the base station at predetermined intervals based on the communication setting, a sensor that acquires biometric information, a recording device that records communication settings for transmitting the biometric information to the base station, and the communication settings. And a communication device. The base station includes a recording device that records communication settings of each of the plurality of terminals, a control device that sequentially selects communication settings of each of the plurality of terminals according to a time allocated to each of the plurality of terminals, and the selected communication setting. And a communication device for communicating with the terminal based on the above.

Also, it is a base station connected to a terminal that acquires biometric information and transmits biometric information at a predetermined interval based on a predetermined communication setting. The base station includes a recording device that records communication settings of each of the plurality of terminals, a control device that sequentially selects communication settings of each of the plurality of terminals according to a time allocated to each of the plurality of terminals, and the selected communication setting. And a communication device for communicating with the terminal based on the above.

According to the present invention, even when the sensor node moves and frequent communication with the base station is required at a plurality of locations, the sensor node power is not consumed excessively. Even when a plurality of sensor nodes are concentrated around one base station, processing delay and data loss can be prevented.

It is an example of composition of a system which collects action information in a plurality of living areas. It is a structural example of the database with which a base station and a base station are provided. It is an example of a structure of the database with which a server and a server are provided. It is an example of a structure of the program with which a base station is provided. It is a structural example of the database which stores the setting for communicating with the sensor node with which a base station is provided. It is a structural example of the database which stores the waveform which the sensor node with which a base station is provided stores. It is a structural example of the database which stores the action parameter | index calculated with the program of the base station. It is an example of the behavior index calculation algorithm with which a base station is provided. It is the figure which showed the example of the communication flow which establishes a connection by radio | wireless between a sensor node and a base station. It is a figure which shows the example which compared the power consumption of the sensor node of a prior art example and a present Example. It is a figure which shows the example of the processing flow in a base station. It is the figure shown about the processing flow of the action parameter | index calculation program with which a base station is provided. It is the figure shown about the processing flow of the data transmission program with which a base station is provided. It is the figure shown about the processing flow of the state determination program with which a base station is provided. It is the figure shown about the processing flow of the communication setting synchronous program with which a base station is provided. It is an example of a block diagram of a sensor node. It is an example of a block diagram showing a memory of a sensor node. It is the example of the block diagram shown about the storage of a sensor node. It is an example of the external view of a sensor node. It is the figure shown about the example of the basic process flow of a sensor node. It is the figure shown about the example of the flow of a wireless communication process of a sensor node. It is the figure shown about the example of the communication setting change process by user operation in a sensor node. It is the figure which showed about the example of the processing flow which carries out the radio transmission of the data which are not transmitted to a base station collectively in a sensor node. It is the figure which showed about the example of the processing flow which wire-transmits the data which are not transmitted to a base station collectively in a sensor node. It is an example of the external view of a cradle. It is an example of the external view which connected the sensor node to the base station using the cradle. It is the figure which showed the example of the flow which establishes communication by wired connection between a sensor node and a base station. It is the figure shown about the example of the communication flow of a base station search and an association.

In the present invention, each of the plurality of sensor nodes transmits data acquired at a predetermined interval based on a preset communication setting (for example, in IEEE 802.15.4, a wireless channel, a PANID, a short address, etc.). On the other hand, a sensor node to communicate with and its communication settings are recorded in advance in the base station, and communication is performed with a plurality of sensor nodes while sequentially switching the communication settings according to the allocation time determined for each sensor node. Communication settings for each sensor node are synchronized between base stations, and the sensor node communicates with a plurality of base stations with one communication setting. Hereinafter, embodiments of the present invention will be described with reference to the drawings.

FIG. 1 is a first embodiment and shows a main configuration of the present embodiment. In this configuration, when the user 8 wearing the sensor node 1 moves to a plurality of main locations where the base station 2 is installed in the daily life, the sensor node 1 is only a specific base station. It is characterized in that it can be connected to a plurality of preset destination base stations without consuming extra power as compared with the case of communicating with. Further, the base station 2 connected to the network 4 can sequentially connect to a plurality of sensor nodes 1 in the vicinity, and as a result, the server 3 collects data measured by the sensor node 1 via the network 4. It is characterized by being able to.

The sensor node 1 is a sensor terminal having a shape suitable for being worn by a person, for example, a wristwatch-type wireless function. The sensor node 1 measures a person's biological information and activity information (movement, temperature, pulse, etc.) and uses the measured data. Data temporarily recorded in a nonvolatile memory provided inside and measured data or data recorded therein to the base station 2 (for example, low-power short-range wireless communication such as IEEE 802.15.4) or general-purpose The data is transmitted by typical digital wired communication (USB or the like). The sensor node 1 is intermittently driven to reduce power consumption by shutting off the power of many internal circuits, except for measuring at a fixed interval of several tens of milliseconds and performing wireless communication at intervals of several seconds. The rechargeable battery has a charge cycle (for example, about 1 or 2 weeks) similar to that of a general mobile phone, which is not burdened in daily life.

In addition, each sensor node 1 is assigned with a unique identification ID (MAC address) for communication. Furthermore, an identification ID (short address) unique only within the network constituted by one base station 2 is also stored. In wireless communication, it is possible to identify which data is transmitted from which sensor node 1 by mainly adding a short address to the data. The connection-destination base station 2 is distinguished by a radio channel that defines a radio frequency band and a PANID that is an identification ID unique to each base station 2 and the network that the base station 2 configures. Set information and send data.

The base station 2 has a wireless communication function for transmitting and receiving radio waves via the antenna 201, a data processing function equivalent to a PC (personal computer) and a server, a communication function, and the like. The base station 2 holds a correspondence table of MAC addresses and short addresses in an internal memory, and can convert all short addresses added to data received from the sensor node 1 into MAC addresses to identify devices. This conversion table can be generated by directly setting a wireless communication program (or protocol). The base station 2 calculates a plurality of indexes necessary for estimating the behavior and state of the user 1 from the data received from the sensor node 1 and records them in an internal database. Further, the base station 2 can transmit the data transmitted from the sensor node 1 and the index data calculated inside the base station to the server 3 connected to the network 4 via the network 4 such as the Internet.

The user 8 is assumed to move to various places assuming the daily life of ordinary people. If there is a base station 2 connected to the network 4 at the destination, and a network by wireless or wired connection can be configured, the data measured by the sensor node 1 is collected on the server 3 at any location. Can do. For example, people who commute to the office spend most of their time in the home or office. By installing base stations in these two locations, most activity information in daily life can be collected in real time. It becomes possible to do. Therefore, for example, in the wireless standard such as IEEE802.15.4, when changing the base station to which the sensor node 1 is connected, a new base station is searched by searching for a neighboring base station and exchanging a wireless channel, PANID, address information, and the like. It becomes possible to connect with various base stations. However, in a series of processes called associations, power is consumed by an order of magnitude or more compared to the case of simply transmitting data. For this reason, sensor nodes that have relatively short measurement intervals, such as those worn by humans, that are relatively short in units of seconds and that have only a coin-sized battery are overloaded. There is a high probability that the charge cycle will not be met.

Therefore, in this embodiment, for example, when the user 8 and the sensor node 1 move in the home network 5, the office network 6, and other networks 7, the sensor node 1 has the same communication settings (wireless channel, PANID, short circuit). Address). That is, even when the base station to be connected is changed, the association is not performed, so that unnecessary power consumption due to the association is unnecessary. In this case, all the communication settings can be made single. However, in wireless communication, the amount of data that can be communicated in one frequency band is limited, and when many devices try to communicate with the same base station at the same frequency at the same time, due to congestion control to prevent interference, Communication efficiency is significantly reduced. Also, the processing capability of the base station 2 is limited, and for example, assuming that an inexpensive PC or the like is used, there is a possibility that a significant processing delay or data loss may occur. Accordingly, it is desirable that the sensor nodes 1 use independent wireless settings.

Since the base station 2 communicates with a plurality of sensor nodes 1 in the vicinity, each of which attempts communication with different wireless settings, the plurality of communication settings are switched in a short time. The information of the communication setting to be switched is prepared in advance in an internal database, and can be added, rewritten and deleted by the user 8 from the outside or by an operation from the server 3.

Further, the allocation time of each setting is also switched according to the state of the sensor node 1. For example, if the sensor node 1 with an ID of A exists in the home network 5 or is in the process of moving to somewhere else, the base station 2 of the office network 6 communicates with the sensor node 1 of A. No allocation time is required. In addition, when the user 8 wearing the sensor node 1 is sleeping or when the state hardly changes, the necessity of collecting information in real time is reduced, and therefore the allocation time can be shortened. That is, the allocation time of communication with the sensor node 1 that is highly necessary to collect the activity state in real time becomes relatively long, and the limited processing capability and communication band of the base station can be used efficiently.

It is necessary to make the same communication setting with a specific sensor node 1 between a plurality of base stations 2. For this reason, the server 3 always stores the latest communication settings of the base stations 2 in all locations, and the communication settings of the base stations 2 are synchronized with this.

The location where the base station 2 is installed may be various places other than homes and offices. For example, there are public places such as stations, airports, and trains. In addition, by incorporating the function of the base station 2 in a mobile device with a communication function such as a mobile phone or a notebook PC having a wide-area wireless communication function, it is possible to make any place in the network.

FIG. 2 is a diagram illustrating the configuration of the base station 2 in detail, and includes a wireless communication unit 200 provided with an antenna 201 and a control device 202 having a data processing function such as a PC or a mobile phone. It has a function of wirelessly and wiredly communicating with the sensor node 1, switching a communication partner, estimating a behavior and a state of the user 8 and controlling a communication allocation time, and a function of communicating with the server 3 via the network 4. It is characterized by.

The control device 202 includes a non-volatile storage unit 203, a calculation unit (CPU) 207, a volatile storage unit (RAM) 208 used for temporary data storage at a higher speed than the non-volatile storage unit 203, a wired, wireless LAN, a mobile phone, and a PHS. Network communication unit 209 having a function of communicating with the network 4 such as the Internet via packet communication, WIMAX, etc., and a general-purpose device that can be connected to various external devices by USB or the like, and can also be connected to the wireless communication unit 200 and the sensor node 1 The I / F 210 is connected to an external AC or DC power source, and a power source device 211 that supplies power to the entire control device 202 is connected to a device such as a mouse or a keyboard for inputting input to the control device 202. The U / I control unit 212 is connected to a display device or the like for a person to view information recorded in the control device 202. Is composed of the display control unit 213 of the eye, it is connected by an internal bus 214. The control device 202 executes various functions by the CPU 207 reading various programs recorded in the nonvolatile storage unit 203 to the RAM 208 and executing them.

The nonvolatile storage unit 203 includes a database 204, a control program 205, and a management program 206. The database 204 includes a sensor waveform 221 that records data measured by the sensor node 1, and a gait and momentum necessary for estimating the behavior and state of the user 8 for each time calculated based on the sensor waveform 221. It includes an action index 220 such as an inclination, and communication settings 222 of a plurality of sensor nodes 1. The control program 205 is a program that controls the entire function of the base station 2 and controls communication with a plurality of sensor nodes 1, recording of received data, calculation of indices, transmission to the server 3, and the like. The management program 206 displays the management screen of the base station 2 for a person such as the user 8 by the display control unit 213 or the U / I control unit 212, and adds a user or a device to the communication setting by a human operation. It is possible to change the setting.

FIG. 3 is a diagram showing in detail the configuration of the server 3. The server 3 is connected to a network 4 such as the Internet, records measurement data and index data collected from the base station 2, and updates the latest communication of all base stations 2. It is characterized by having a database recording settings.

The server 3 includes a nonvolatile storage unit 301, a calculation unit (CPU) 302, a volatile storage unit (RAM) 303, a power supply device 304, and a network communication unit 305. In particular, the performance of the nonvolatile storage unit 301, the CPU 302, and the RAM 303 is desirably higher speed and larger capacity than a general PC.

The nonvolatile storage unit 301 includes an analysis program 306, a base station communication program 307, a database 308, and a visualization program 313. The database 308 includes an action index 310, a sensor waveform 311 and a communication setting 312. The behavior index 310 is obtained by collecting and recording the behavior indices 220 of all base stations 2. Similarly, the sensor waveform 311 is collected and recorded from the sensor waveforms 221 of all the base stations 2. That is, the server 3 collects all data measured by the sensor node 1 without depending on the location of the sensor node 1 or the base station 2. The communication setting 312 is a combination of all the base station 2 communication settings 222 and is updated when the base station 2 communication settings 222 are changed.

Based on the behavior index 310 and the sensor waveform 311, the analysis program 306 monitors the behavior and life rhythm, safety and health status of the user 8, and analyzes the relationship between the work at the office and the lifestyle. Is. These analyzes are performed for each user 8, but require long-term continuous data. For example, if the relationship between sleep at home and work efficiency at the office is derived by analysis, the analysis is impossible if each data is recorded separately at home and office. It is also possible to collect all measurement data at one base station after recording all the measurement data at the sensor node 1 with either one of the base stations. However, if the base station is installed only in the home, it is impossible to know the activity state of the place in the office where a lot of time is spent in the day. The same is true if it is installed only in the office, and data cannot be collected and used for analysis on holidays. Also, even when analyzing for the purpose of watching, if the base station is in one place, it is impossible to know whether it is safe or healthy in a lot of time, and the purpose of watching cannot be achieved. For example, even when it is desired to monitor the safety of a child who goes to school, it is necessary to know the real-time activity state at both the school and the home if the parent is away from home at work or the like. Therefore, in this embodiment, the analysis program 306 is executed in the server that collects the data measured by all the sensor nodes and the behavior indicators possessed by all the base stations.

The base station communication program 307 is a program that collects data of the action index 220, the sensor waveform 221 and the communication setting 222 from all the base stations 2 by communication means via the network 4 such as HTTP or HTTPS.

FIG. 4 shows in detail the configuration of the control program 205 and the management program 206 in the base station. The control program 205 calculates a necessary index for estimating the behavior and state of the user 8 from the data measured by the sensor node 1 and the cyclic communication program 231 that communicates while switching to a plurality of sensor nodes 1 and stores it in the database. A behavior determination calculation program 235 to be recorded, a state determination program 233 for determining the behavior and state of the user 8 using the index calculated by the behavior index calculation program 235, and adjusting the communication allocation time of each sensor node 1, and the network 4 And a data transmission program 234 for transmitting database information to the server 3 via the network, and a communication setting synchronization program 232 for synchronizing communication settings with the server 3.

The cyclic communication program 231 controls the wireless communication protocol 230 having the control function of the wireless communication unit 200 and the general-purpose I / F 210 such as USB to control the wired communication protocol 238 to perform wired communication with the sensor node 1 to perform communication. The communication with the sensor node 1 is performed so that the list of communication settings of the sensor node 1 corresponding to the plurality of users 8 set in the setting 222 is circulated at each assigned time. The allocated time is measured by the timer 236. The received data is recorded in the sensor waveform 221.

The behavior index calculation program 235 calculates an index necessary for estimating a human behavior and state from the sensor waveform 221 and records it in the behavior index 220. For example, when the sensor waveform 221 is motion data such as three-dimensional acceleration measured at intervals of several tens of milliseconds, it is difficult to directly estimate human behavior from the acceleration waveform data. Therefore, from the waveform data of the movement, the amount of exercise in seconds and minutes, the intensity of the exercise, the number of steps, the average inclination, etc., which are easier to understand, are calculated and recorded in the action index 220.

In the behavior state determination program 233, the behavior and state of the user 8 wearing the sensor node 1 are estimated from the behavior index 220, and the allocated time recorded in the communication setting 222 is adjusted based on the determined behavior. . For example, when there is a difference of one hour or more between the latest date and time in the behavior indicator 220 and the current date and time for a certain user 8, it can be understood that the user 8 is not in the vicinity of the base station. In addition, if you are nearby, you can see whether you are sleeping or exercising, just after coming to the spot, desk work, watching TV, based on the amount of movement, that is, the amount of exercise and the number of steps. You can know if you are resting. Based on such information, for example, if there is no data, the probability of receiving data is small, so the allocation time is reduced. In addition, the allocated time is reduced because there is little change in behavior during sleep as well. When there are many behavioral changes and movements, there is a high possibility that communication is partially interrupted, and it is necessary to collectively receive data recorded in the sensor node 1, so that the allocation time is lengthened. In this way, by controlling the allocation time of each sensor node according to the state of the user wearing the sensor node, the limited processing capability and communication bandwidth of the base station can be used effectively, and the sensors around the base station Data can be received from the node. Thereby, compared with the case where allocation time is fixed, the processing delay and data loss of a base station can be further prevented.

The data transmission program 234 reads out only data that has never been transmitted to the server 3 from the sensor waveform 221 and the behavior indicator 220, and performs general-purpose network communication such as HTTP and HTTPS via the network communication unit 209. Send by means.

The communication setting synchronization program 232 is a program for synchronizing the communication setting 312 of the server 3 and the communication setting 222 of the base station 2. For example, when the communication setting 222 is changed / added on a certain base station 2 side, it is reflected in the communication setting 312 of the server 3, and the communication setting 312 and the communication setting 222 of the server 3 are synchronized in the other base stations 2.

The management program 206 includes a user screen program 225 and a user management program 226. The user screen program 225 receives an operation from the administrator of the user 8 or other base station 2 via the U / I control unit 212, and displays a management screen for changing the communication setting 222 via the display control unit 213. This is a program to be provided. The user management program 226 is a program that provides a function for rewriting the contents of the communication setting 222 based on the operation received by the user screen program 225.

Further, instead of the user directly inputting settings or the like to the management program 206, it may be accessed and changed from an external network device.

In this case, the management program 206 includes a Web server program, and accepts a request based on a protocol such as HTTP or HTTPS via the network. For example, when a screen display for changing the communication setting 222 is requested, a means for changing the communication setting 222 is presented to the authorized user 8 or administrator via the user management program 226. Further, when a change request is made, the communication setting 222 is changed via the user management program 226.

FIG. 5 shows the configuration of the communication setting 222 of the base station 2 in detail, and is characterized in that each user 8 has a unique setting value and allocation time. The communication setting 222 includes a user setting 240, a wireless communication setting 241, and a wired communication setting 242.

The user setting 240 includes a user ID 251 that is an identification ID of the user 8, a type 252 for distinguishing whether to use wireless, wired, or both, and wireless communication that records detailed communication settings. The setting ID 253 that is a link to the setting 241 and the wired communication setting 242, the allocation time 254 that is the communication allocation time for each user, and the changed line when the communication setting 222 is changed are notified to the communication setting synchronization program 232. , And a change flag 255 that is a flag to be reflected in the communication setting 312 of the server 3.

The wireless communication setting 241 indicates detailed setting contents when the type 252 is wireless in the user setting 240. The setting ID 256 corresponds to the setting ID 253, and one line includes a wireless channel 257, a PAN ID 258, a MAC address 259, and a short address 260. If the combination of the wireless channel 257 and the PANID 258 is independent in all the sensor nodes 1, all the short addresses 260 have the same value. When the combination of the wireless channel and the PANID is exhausted and becomes independent, there is a sensor node 1 that shares the same wireless setting (wireless channel and PANID), and therefore a different short address 260 is assigned to distinguish them. .

The wired communication setting 242 indicates detailed setting contents when the type 252 is wired in the user setting 240. The setting ID 261 corresponds to the setting ID 253, and a device ID 262 is assigned to each. The device ID 262 is an independent value for all the sensor nodes 1, and may be the same as the MAC address 259 when the sensor node 1 has a wireless communication function. In the case of wired communication, the communication speed is sufficiently higher than that of wireless communication, and since power is supplied if USB is used, the device ID is transmitted each time when communication is started or periodically. 1 communication is established.

FIG. 6 shows an example of the data structure of the sensor waveform 221, characterized in that the measurement data received from the sensor node 1 is recorded with user information and a flag indicating whether it has been transmitted to the server 3. To do. In the example of FIG. 6, it is assumed that the sensor node 1 measures acceleration, temperature, pulse wave, and battery voltage. The structure of one line of the sensor waveform 221 includes a user ID 280 which is an identification ID of the user 8, a date 281 indicating the date and time measured by the sensor node 1, an acceleration x282 indicating an acceleration based on the gravitational acceleration, an acceleration y283, and an acceleration z284. A pulse wave 285 relatively indicating the blood flow of the blood vessel, a temperature 286, a voltage 287 indicating the battery voltage, and a transmitted flag 288 indicating whether data has been transmitted to the server 3. The transmitted flag 288 is referred to from the data transmission program 234. If it is 0, it is transmitted to the server 3 to indicate that it has not been transmitted. If it is 1, it is not transmitted because it has been transmitted. The transmission completion flag 288 is rewritten to 1 after the data transmission processing of the row.

FIG. 7 shows an example of the data structure of the behavior indicator 220. For the detailed sensor waveform 221 in milliseconds, a value that summarizes behavior characteristics in a long time unit such as seconds or minutes is calculated and recorded. It is characterized by that. One line of the data table of the behavior index 220 includes the user ID 270, the date and time 271, the momentum 272 indicating the number of times the scalar value (absolute value) of the three-axis acceleration that is a vector vibrates, and similarly the amplitude of the scalar value of the acceleration. The exercise intensity 273 shown, the number of steps 274 calculated by a known method such as autocorrelation from the periodicity of the acceleration waveform, the slope x275 that is the average value of the acceleration x282, the slope y276 that is the average value of the acceleration y283, and the acceleration A slope z277, which is an average value of z, and a transmitted flag 278 indicating whether the data in the row has already been transmitted to the server 3 or not. The transmitted flag 278 is the same as the transmitted flag 288 and is referred to by the data transmission program 234. If it is 0, it is transmitted to the server 3 and rewritten to 1.

FIG. 8 is a diagram showing in detail a method for calculating the amount of exercise 272 and the exercise intensity 273 of the behavior index 220. The graph shown in FIG. 8 is a value obtained by converting vector triaxial acceleration into a scalar value. The momentum 272 is the number of times the scalar value oscillates per unit time, that is, the number of times 291 that intersects the center value. However, when the center value is set to 0, it is likely that many noise components that are not movements associated with human behavior are detected. For this reason, in the present embodiment, 0.03G is set as a reference central value as a threshold value for easily detecting only human behavior. The exercise intensity 273 is an integral value of the scalar value, that is, the sum 290 of the amplitude of the scalar value per unit time.

FIG. 28 shows an example of a sequence in which the sensor node 1 associates with the destination base station 2 and starts a connection in accordance with IEEE 802.15.4 as in the prior art. In order for the sensor node 1 to change the wireless setting in accordance with the base station 2 as the movement destination, base station search and association processing are required.

In the base station search, the sensor node 1 transmits a beacon request for requesting a PANID to the base station 2, and waits for reception of a beacon including the PANID from the base station. However, since it is not known which radio channel is used by the base station 2 in the vicinity, the same processing is performed for all radio channels (16 channels in IEEE 802.15.4). For this reason, in particular, the total reception standby time is 10 to 100 times that of the normal data transmission time, and power consumption is also required. This process is the process that consumes the most power in the sensor node 1. In addition, when there is no base station in the vicinity and a beacon cannot be received, it is necessary to perform search processing at regular intervals.

Next, when a beacon can be received from the base station 2, an association is performed using the specified radio channel and PANID. In the association, the sensor node 1 includes a MAC address, transmits a connection request for requesting a short address to the base station, and receives assignment of the short address. After completion of the association, transmission of sensor data immediately after measurement is started. When the wireless communication unit 200 of the base station 2 correctly receives the sensor data, the wireless communication unit 200 transmits Ack to the sensor node 1. When the sensor node 1 receives Ack, it is assumed that data transmission is successful. Thereafter, the sensor node repeats the transmission of sensor data and the reception of Ack, and when Ack cannot be received, performs the base station search and association again.

In contrast to FIG. 28, FIG. 9 shows an example of a sequence of communication processing with the base station at the movement destination of the sensor node 1 according to the present embodiment. In the present embodiment, the sensor node 1 repeatedly executes sensor data transmission 326 at a constant interval (for example, every second) even when the connection with the base station is not established. To do. Then, the base station performs processing for sequentially switching communication settings of a plurality of sensor nodes registered in advance. That is, the control device selects the communication setting 328 based on the time allocated for each sensor node and transmits it to the wireless communication unit. When the communication setting of the wireless communication unit matches the setting of the sensor node, Ack 330 is returned to the sensor data transmission 329, and communication is established. Therefore, the sensor node simply repeats the same process as the normal data transmission process, and the result is the same as the search and association process.

Here, when there are a plurality of sensor nodes, different communication settings are used to avoid concentration of radio band and processing. In this case, if the setting used by the base station for communication (wireless channel, PANID) is different from the communication setting of the sensor node, Ack is not returned.

Next, the sensor data received by the wireless communication unit is transmitted to the control device (331) and recorded in the sensor waveform 221. If the sensor node succeeds in data transmission, it is assumed that it is still connected to the base station, and data recorded in the storage inside the sensor node in a state where communication with the base station has not been established (in this case, untransmitted) Data transmission).

Note that the measurement time of these untransmitted data is delayed compared to the time of transmission and is not real time. Therefore, in this embodiment, untransmitted data recorded in the storage is transmitted to the base station as fast as possible in order to eliminate the data delay and approximate real time. However, at the timing of the next sensor data transmission 332 acquired in real time, the sensor data transmission 332 is prioritized and the transmission of untransmitted data is interrupted. The sensor data transmission 332 is the timing at which the data measured by the sensor node at regular intervals is stored in the sensor node memory up to the transmission capacity (packet size) that can be transmitted by one data transmission. Is desirable. Also, transmission of untransmitted data is interrupted on the assumption that a connection has not been established when the Ack response from the base station is interrupted.

The base station controller newly calculates a behavior index 220 from the sensor waveform 221 and executes transmission 333 of behavior index data to the server. In the base station, when the allocation time of the currently communicating sensor node elapses, the control device transmits a communication setting 334 to the wireless communication unit in order to switch to the next setting. When the communication setting is switched in the wireless communication unit, the response of Ack to the data transmission 335 of the sensor node is interrupted. The sensor node sets this state as a state where communication is not established, and repeats the process of the data transmission period 324.

In this way, in the series of processes in FIG. 9, compared with the conventional method shown in FIG. 28, the search and association processes are not performed even when the sensor node moves and the communication base station changes. Will not be consumed. Even if a plurality of sensor nodes 1 exist in the vicinity of the base station, the communication settings corresponding to each sensor node are switched at a predetermined allocation time. There is no problem.

Note that it is not always necessary to transmit actual measurement data for the data transmission period 324 in which the data transmission 326 is repeated in a state where the connection with the base station 2 is not established. If the response of Ack is interrupted (for example, Ack is not returned 10 times in succession) and it can be determined that communication has not been established, in order to save transmission power, the data content can be emptied or the transmission interval can be reduced. It is effective to divide it from the purpose of transmitting measurement data by extending the interval from 1 second to 1 minute.

FIG. 10 is a diagram showing an example in which the conventional process shown in FIG. 28 is compared with the power consumption of this embodiment. For example, when the sensor node 1 is configured with a wireless IC conforming to IEEE802.15.4 and a general-purpose 8-bit microcomputer, typical current consumption of the sensor node 1 is a current 501 during sensing and a current during wireless transmission. As shown in 502. Note that the processing at the time of wireless transmission includes activation of the wireless communication unit, scanning of surrounding radio wave conditions for congestion control (channel scanning), data transmission, Ack reception, data compression, and writing to storage. For example, the current 506 indicates the current when measured at 50 millisecond intervals and the measured data is transmitted collectively at 1 second intervals.

For such normal data transmission, the base station search 505 takes 15 milliseconds or more even when waiting for a beacon of one channel. Therefore, if this is performed for all channels, a search time of at least 250 milliseconds is required, and during this period, the peak current continues to flow. As described above, in the conventional base station search and association process shown in FIG. 28, since the reception standby time of the sensor node 1 becomes longer, the power consumption becomes 10 times or more that during normal data transmission.

FIG. 11 is a diagram showing the overall flow of processing performed in the base station, and particularly shows the processing of the cyclic communication program 231 in detail. FIG. 11 is characterized in that the base station switches sensor nodes that communicate with each other at a predetermined allocation time. The cyclic communication process is started in process P1. This program can be interrupted and stopped in any state by an external operation.

In process P2, the communication setting synchronization program 232 is read into the RAM 208 of the control device 202, and the communication setting synchronization process is started. In process P3, communication settings 222 for use in communication are sequentially read into the RAM 208 of the control device 202. If it is immediately after starting this program, the top setting of the communication setting 222 table is read, and if there is a setting that has already been read, the next setting is read. In the process P4, the allocation time 254 of the communication setting 222 read out in the process P3 is set in the timer 236, and the timer count is started. In process P5, if the type 252 of the communication setting 222 read in process P3 is wireless, the wireless communication protocol 230 is activated, the corresponding wireless communication setting 241 is sent to the wireless communication unit 200, and the wireless communication unit is activated. . If the type 252 is wired, the wired communication protocol 238 is activated.

In process P6, if radio is selected in process P5, any data received by the radio communication unit 200 via the radio communication protocol 230 is recorded in the sensor waveform 221. If wired is selected, if the sensor node 1 that matches the device ID 261 in the wired communication setting 242 is connected to the general-purpose I / F 210, communication is started and data is received. In the process P7, the action index calculation program 235 is read out to the RAM 208 of the control device 202, and the action index calculation process is started. In process P8, the data transmission program 234 is read to the RAM 208 of the control device 202, and the data transmission process is started. In process P9, the state determination program 235 is read into the RAM 208 of the control device 202, and the state determination process is started.

In process P10, the state of the timer 236 is read. If the preset time has elapsed, the process proceeds to process P11. If not, the process proceeds to process P6. In the process P11, if the radio is selected in the process P5, the radio communication protocol 230 and the radio communication unit 200 are stopped. If wired is selected, the wired communication protocol 238 is stopped. When communication is stopped in process P11, user switching is performed (P12), and the process proceeds to process P2.

FIG. 12 shows the processing procedure of the behavior index calculation program 235 in detail. The action index calculation process is started from process P100. In the present embodiment, the behavior index is calculated when sensor waveform data for a predetermined time (1 minute in this example) or more is accumulated. In the process P101, the behavior index 220 and the sensor waveform 221 are read, and if the time (uncalculated time) of data existing in the sensor waveform is 1 minute or more, the process shifts to the process P102. If it is shorter than 1 minute, the process proceeds to process P108, and the behavior index calculation process is terminated.

In process P102, the sensor waveform 221 data corresponding to the uncalculated time in process P101 is read. In process P103, the momentum is calculated from the acceleration x282, acceleration y283, and acceleration z284 of the read sensor waveform 221 based on the calculation method shown in FIG. In the process P104, the exercise intensity is calculated based on the calculation method shown in FIG. 8, and in the process P105, a known method such as autocorrelation of the waveform of the scalar value of the acceleration vector from the acceleration x282, the acceleration y283, and the acceleration z284. To calculate the number of steps. In the process P106, an average value (for example, for one minute) is calculated from the acceleration x282, the acceleration y283, and the acceleration z284 to obtain the inclination. In the process P107, the results calculated in the processes P103 to 106 are recorded in the action index 220, the process proceeds to the process P108, and the action index calculation process is completed.

FIG. 13 shows an example of the processing procedure of the data transmission program 234. In FIG. 13, the behavior index 220 is transmitted at the earliest possible timing, and the time when the processing load of the base station is low, for example, the large-capacity sensor waveform 221 is the time when the user 8 wearing the assigned sensor node 1 is absent. It transmits to a server collectively, It is characterized by the above-mentioned. A data transmission process is started from process P200.

In process P201, the presence / absence of untransmitted data to the server 3 is detected based on the transmitted flag 278 of the behavior indicator 220. If there is untransmitted data, the process proceeds to process P202, and if not, the process proceeds to process P208 to complete the data transmission process. In the process P202, data corresponding to the untransmitted time in the process P201 is read from the behavior indicator 220. In process P203, the data read in process P202 is transmitted to the server 3 via the network communication unit 209.

In process P204, the transmission completion flag 288 of the sensor waveform 221 is referred to and the presence / absence of sensor waveform data not transmitted to the server is detected. If there is data that has not been transmitted to the server 3, the process proceeds to process P205, and if not, the process proceeds to process P208 to complete the data transmission process.

In process P205, the sensor waveform 221 is referred to, and if the difference between the time of the latest measurement data of the currently assigned user and the current time is, for example, 10 minutes or more, it is considered absent, and the process proceeds to process P206. If it is less than 10 minutes, the process proceeds to process P208 to complete the data transmission process. This is because the probability of receiving data from the sensor node is low and the processing load of the base station is low when it is absent, and therefore, using this time, the sensor waveform 221 having a larger capacity than the behavior indicator 220 is used. Is sent to the server.

In process P206, the data not transmitted in process P204 is read into the RAM 208 of the control device 202.

In process P207, the data read in process P206 is transmitted to the server 3 via the network communication unit 209. After the transmission is completed, the data transmission process is completed in process P208.

FIG. 14 shows an example of the processing procedure of the state determination program 233. FIG. 14 is characterized in that the communication allocation time is controlled in accordance with the state of the user 8. Specifically, the allocated time is increased or decreased depending on whether the user 8 is absent, whether the user 8 is sleeping, or whether the behavior is changed. The state determination process is started from process P300.

The process P302 is the same as the process P205 of FIG. 13, and if it is determined that the assigned user 8 is not present in the vicinity thereof, the process shifts to the process P310. If not, the process proceeds to process P303. In process P310, the communication setting 222 is accessed, and the current allocation time 254 of the user 8 is reduced by a predetermined amount (for example, about 50%). However, since a minimum startup time is required within the allocated time, it is desirable to secure about 10 seconds at the shortest.

In process P303, the action content is determined based on the action index 220. A known method is used as the discrimination method. For example, a method based on the amount of exercise or exercise intensity can be used (METS method or the like). Further, it can be easily estimated that there is a behavior transition when walking or when there is a sudden change in momentum. In other words, after separating behavior transitions, you can classify behaviors such as sleep, rest, desk work, exercise, walking, and work from the momentum between the transitions, and determine postures such as sitting and standing from tilt information be able to.

In process P304, if the action content determined in process P303 is sleep, the process proceeds to process P311. If not, the process proceeds to process P305. The process P311 is a process for reducing the allocation time, like the process P310.

In process P305, when the transition of the action content determined in process P303 is looked back for about the past 5 to 10 minutes, if there is a change, the process proceeds to process P306, and if there is no change, the process proceeds to process P312. The process P312 is a process for reducing the allocation time, like the process P310. Process P306 is a process for increasing the allocation time. The maximum value at this time can be set to a value of about 1 to 10 minutes, or for example, the maximum cycle for circulating the whole can be set to 30 minutes and the cycle divided by the number of registered users. In the process P307, the state determination process is completed.

FIG. 15 is a diagram illustrating an example of a processing procedure of the communication setting synchronization program 232. In FIG. 15, the setting contents changed in the base station 2 are synchronized with the server 3, and the contents changed in the other base stations 2 are synchronized through the server 3. Thereby, each base station can reflect the latest communication settings of a plurality of sensor nodes. The communication setting synchronization process is started from process P400.

In process P401, the communication settings of all users registered from the communication settings 222 are read out to the RAM 208 of the control device 202. In process P402, the change flag 255 of the communication setting 222 read to the RAM 208 in process P401 is referred to. The change flag 255 is set to 1 when the radio channel, the PANID, and the short address in the communication setting 222 are changed in the base station 2. If there is a line in which the change flag 255 is 1, the process proceeds to process P403.

In process P403, the data in the row in which the change flag 255 of the communication setting 222 is 1 is transmitted to the server 3 via the network communication unit 209 and reflected in the communication setting 312. In process P410, all lines corresponding to the user registered in the communication setting 222 are read out from the communication setting 312 of the server 3 via the network communication unit 209.

In the process P411, the communication setting data read in the process P410 and the data of the communication setting 222 read in the RAM 208 are compared, and if there is a difference, the process proceeds to the process P412 and the difference contents are reflected in the communication setting 222. Synchronize with the communication setting 312 of the server 3. If there is no difference, the process proceeds to process P404. In process P404, the communication setting synchronization process is completed.

The behavior index 310 can also be calculated from the sensor waveform 311 by executing the analysis program 306 by the server. In this case, the base station can receive the behavior index calculated by the server, estimate the user's behavior and state, and control the user's communication allocation time based on the estimated behavior. Furthermore, by executing the analysis program 306 by the server, it is possible to estimate the user's behavior and state from the behavior index and calculate the communication allocation time. In this case, the base station can receive the communication allocation time calculated by the server and can communicate with each sensor node based on the communication allocation time.

Also, the base station can use the result of the server executing the analysis program 306 for the behavior state determination described above. For example, the server specifies that the sensor node A is within the range of the base station A based on the user ID and the ID of the base station included in the data received from the base station A, and sets the location information to another base station B. Send to. The base station B can determine that the user of the sensor node A is absent based on the location information of the sensor node A, and can reduce the communication allocation time of the sensor node A.

16 to 18 are block diagrams of the sensor node 1 of the present embodiment. Here, the sensor node 1 is controlled by executing a sensing program 422, a wired communication program 423, and a wireless communication program 424 recorded in the ROM 420. Specifically, by executing a sensing program, the periodic signal from the real-time clock 438 is used as a trigger for sensing at an arbitrary period, and the data is taken into the RAM 410 and recorded in the storage 460. By executing the wireless communication program, the data measured by the sensing program 422 is wirelessly transmitted to the base station 2, and the data transmission is performed without searching or association processing even if the connection with the base station 2 is not established. Continue. Furthermore, by executing the wired communication program, the external power supply detection unit 432 reads out data from the storage 460 using a connection with an external device such as a personal computer via USB as a trigger, and starts wired transmission to the external device. Each will be described below.

The sensor node 1 includes a wireless communication unit (RF) 431 including an antenna 450 that communicates with a base station, an acceleration sensor 435, a temperature sensor 436, a pulse sensor 437, a microcomputer 400, and the microcomputer 400 at regular intervals. The microcomputer 400 can trigger a real-time clock (RTC) 438 that functions as a timer for triggering, a storage 460 that is a nonvolatile storage medium, an LCD 434 that displays characters, waveforms, graphs, and the like. A plurality of switches 441, 442, an external power supply detection unit 432 that detects a USB connection from an external device to the terminal 470, triggers the microcomputer 400, and outputs the state to the microcomputer 400; Syria USB communication unit 433 for transferring data transmitted by communication to a USB-connected external device, a switch 444 for cutting off a signal line with USB communication unit 433 by a signal from a microcomputer, a secondary battery 447, and an external device To the charging unit 439 for charging the secondary battery 447 with the power supplied via the USB connection, the voltage detection unit 440 for outputting the voltage of the secondary battery 447 to the microcomputer 400, the regulator 446, and the regulator 446 The power supply switching unit 445 that switches the power supply to be supplied between the secondary battery 447 and the external power supply via USB, the terminal 470 that connects the USB cable, and the reset terminal 475 are cut off from the power supply from the secondary battery. It includes a reset switch 443 for resetting.

The microcomputer 2 converts a CPU 401 that executes arithmetic processing, a ROM 420 that records a program 421 to be executed by the CPU 401, a RAM 410 that temporarily records data and the like, and an analog signal input from the outside into a digital signal. A / D converter 404, I / O port 405 for inputting or outputting digital signals from the outside, real time clock 438, storage 460, LCD 434, acceleration sensor 435, temperature sensor 436, pulse sensor 437, wireless The serial communication units 403 and 408 that transmit and receive signals with serial signals in the communication unit, the DMAC 402 that controls the serial communication unit 403 without going through the CPU 401 and imports data received by serial communication into the RAM 410, and the external Trigger signal Configured to include an interrupt controller 406 and 407 interrupt the CPU401 running program 421 and. These are connected via a bus 409.

The programs 421 recorded in advance in the ROM 420 include a sensing program 422 and a wired communication program 423. The processing described in the sensing program 422 is executed by the CPU 401, and the data sensed by the acceleration sensor 435, the temperature sensor 436, and the pulse sensor 437 is taken into the RAM 410 via the serial communication unit 403 using the signal of the real time clock 438 as a trigger. Then, the wireless communication unit 431 is controlled to wirelessly transmit the data fetched into the RAM 410 to a predetermined base station, and further written into the storage 460 and recorded.

The processing described in the wired communication program 423 is also executed by the CPU 401, starts wired communication using a signal from the external power supply detection unit 432 as a trigger, is recorded in the storage 460 via the serial communication unit 403, and is wireless or Data that has not been transmitted to the outside by wire communication (untransmitted data) is read, transmitted to the USB communication unit 433, and transmitted from the USB communication unit 433 to the external device by wire. In the processing of the wired communication program 423, data (transmitted data) that has been transmitted once wirelessly and by wire can be sent again.

Further, the wired communication program 423 can read the data in the storage 460 and record it in the RAM 410 without controlling the DAMC 402 and executing the processing by the CPU 401. Accordingly, since the CPU 401 can execute another process while the storage 460 is being read, data can be transmitted from the RAM 400 to the USB communication unit 433. Also in the transmission to the USB communication unit 433, the DMAC 402 can be controlled to transfer data from the RAM 410 without using the CPU 401.

As shown in FIG. 17, the RAM 410 is a rewritable value such as a parameter 411, a wireless communication state 412, a wired connection state 413, a wired communication state 414, and a transmission for temporarily recording data for wireless transmission. A trust buffer 415, a storage buffer 416 for temporarily recording data read from the storage 460 and data to be written, a read address 417 indicating the position of the data in the storage 460 when reading unsent data from the storage 460, When the sensed data is written, a write address 418 indicating a write position in the storage 460 is provided.

The parameter 411 is a value that defines the operation of the sensor node 1 and can be changed by the user. A wireless channel indicating a wireless frequency used when wireless communication is performed by controlling the wireless communication unit 431, a unique ID (PANID, short address) for identifying a sensor node, and the like are recorded. The wireless communication state 412 records the result of transmitting sensed data, that is, the result of successful transmission or failure. The wired connection state 413 records whether or not the external device is connected via USB. The wired communication state 414 records whether or not the external device of the other party can receive data while being connected to the external device via USB. The transmission buffer 415 is an area in which data sensed by the acceleration sensor 435, the temperature sensor 436, and the pulse sensor 437 is temporarily recorded and accumulated until the transmission capacity is reached. For example, when the wireless standard is IEEE 802.15.4, the data capacity (packet capacity) that can be transmitted at one time is set to about 100 bytes. The storage buffer 416 is an area for data that is compressed and transmitted to the storage 460 for recording after the data in the transmission buffer 415 is transmitted. In addition, when data is read from the storage 460 and transmitted wirelessly or by wire, it is also an area for recording the read data. In this embodiment, when a typical known compression method is applied, for example, waveform data with a maximum acceleration of 3G and a minimum of -3G sampled at 20 hertz can be compressed to about 1/3 on average. Therefore, data corresponding to one packet capacity is stored in the storage buffer 416 and then recorded in the storage 460. As a result, the writing frequency can be reduced.

Due to the characteristics of both the transmission buffer 415 and the storage buffer 416, real-time data immediately after sensing is transmitted wirelessly and recorded in the storage 460, and if it can be communicated with an external device wirelessly or by wire, it is not transmitted from the storage 460. Both processes of reading and transmitting data can be executed without delay.

The read address 417 indicates the position in the storage 460 of untransmitted data to be transmitted when wireless or wired communication is possible. The write address 418 indicates a position in the storage 460 where data for writing to the storage 460 recorded in the storage buffer is to be recorded. That is, when the read address 417 and the write address 418 have the same value, it can be determined that there is no untransmitted data to be transmitted in the storage 460.

The storage 460 includes a data table 461 for recording sensed data. The data table will be described with reference to FIG. The data recorded in the data table is delimited by a variable length for each packet when transmitted from the wireless communication unit 431. As a result, after one packet of data read from the storage 460 is temporarily recorded in the storage buffer 416, the processing can be reduced by enabling wireless or wired transmission without processing the data as it is.

One packet is recorded at the position of the corresponding address, and the flag and length are also recorded in the data table 461 at the same time. The address is uniquely assigned in the data table 461, and one address indicates the position of one corresponding data. The storage 460 can read or write data at any position recorded in the storage 460 by referring to an address included in the write command read from the microcomputer 400 by serial communication. The length indicates the data length of the corresponding packet. That is, the address of the next recorded packet can be determined by adding the length to the address of the corresponding packet.

In the flag, 1 is written if transmission is successful when the data is transmitted after being recorded in the transmission buffer 415, and 0 is written if transmission failure data is included. That is, when a packet in the storage 460 is read later, it can be determined whether or not untransmitted data is included, and only untransmitted data can be efficiently read without being left.

The packet 462 indicated by the write address 418 of the RAM 410 indicates the oldest packet recorded last in the data table 461. This is because by rewriting from the oldest data, the number of rewrites is equalized in all recording units (one cell of the memory) in the storage, and the rewrite frequency is reduced. A packet 463 indicates a packet including transmitted data in the data table 461. Since the packet 463 includes transmitted data, the flag is 1.

A packet 464 indicated by a read address 417 of the RAM 410 indicates a packet including untransmitted data recorded last in the data table 461. Since the packet 464 includes untransmitted data, the flag is always 0. In other words. By simply reading a packet with a flag of 0 from the packet indicated by the read address 417, it is possible to read without leaving untransmitted data.

The real time clock 438 can generate an interrupt signal to the interrupt control unit 406 of the microcomputer 400 at a constant cycle. This period can be changed by a serial communication command. With this interrupt signal, the microcomputer 400 can start the sensing process described in the sensing program 422 at a constant cycle without being affected by the execution state of other processes.

Real time clock 438 has an external input terminal. That is, by connecting the switches 441 and 442 that are buttons to the external input terminal, the microcomputer 400 can be similarly interrupted when the button is pressed. These input states can be read out to the microcomputer 400 by serial communication, and the type of button and the pressed length can be detected. By using the operations of the switches 441 and 442, the setting change of the parameter 411 can be executed.

The external power supply detection unit 432 detects that the power supply terminal 471 of the terminal 470 is connected. That is, it is possible to detect connection with an external device via a USB having a power source. When connection is detected, the external power supply detection unit 432 generates an interrupt signal to the interrupt control unit 407 of the microcomputer 400 and outputs a digital signal 1 to the I / O port 405. When disconnection is detected, an interrupt signal is generated and a digital signal of 1 is output to the I / O port 405. That is, the microcomputer 400 can immediately detect a change in the connection state to the terminal 470 and start or stop USB communication via the USB communication unit 433. Further, by controlling the switch 444 by the output of the I / O port 405 from the microcomputer 400, the communication line for the serial signal can be cut off immediately when communication is stopped. This is a function of suppressing current leakage flowing from the microcomputer 400 to the USB communication unit 433 through the signal line because power is not supplied to the USB communication unit 433 when the terminal 470 is not connected.

The USB communication unit 433 converts a serial communication signal with the microcomputer 400 into a USB standard signal via USB data terminals (transmission and reception) 472 and 473. Therefore, in the control of the microcomputer 400, only the data to be transmitted to the external device can be automatically converted to the USB standard data and transmitted to the external device only by transmitting to the USB communication unit 433 by serial communication. In addition, since the power of the USB communication unit 433 is supplied only from an external device via the power terminal 471, no extra power is consumed when the USB is not connected.

The power supply switching unit 445 switches the power supplied to the regulator 446 between the power supplied from the built-in secondary battery 447 when the USB is not connected and the power supplied from an external device via the power terminal 471 when the USB is connected. . Therefore, the secondary battery 447 is not consumed even when wired communication is continuously used during USB connection.

FIG. 19 shows the external appearance of the sensor node 1 to which this embodiment is applied. In FIG. 19, since the USB connection terminal 470 of the sensor node 1 is on the side as viewed from the mounting surface with the pulse sensor 437, the user can always wear it during wired communication and charging, and sensing is performed. It is characterized by not obstructing. Each will be described below.

The sensor node 1 has bands 9 attached to both ends, and can be worn on the arm in the same manner as a typical wristwatch. As can be seen from the structure of the band 9 in FIG. 19, the surface having the pulse sensor 437 contacts the user's skin when worn. The pulse sensor 437 is a known optical measurement method, which irradiates infrared rays on the surface of a living body, and makes it possible to estimate a pulse from a change in reflected light due to pulsation of blood vessels. That is, it is essential that the pulse sensor 437 is in contact with the user's skin.

Terminal 470 is on a different side from the mounting surface where pulse sensor 437 is located. A terminal 470 corresponds to a USB cable, and can be connected to an external device compatible with USB through a power terminal 471, data terminals (transmission and reception) 472 and 473, and a ground terminal 474, and can communicate and supply power. Further, by short-circuiting the reset terminal 475 and the ground terminal 474, it is possible to shut off the internal power supply from the outside and apply a reset. Only the electrodes of the terminal 470 are exposed and can be waterproofed.

Also, the LCD 434 can display the time that the user can always see, the remaining battery level, the wireless communication status, and the like. By displaying a menu on the LCD 434 and operating the switches 441 and 442, the user can change the sensing interval, the wireless channel, and the like. It is also possible to execute sensing or wireless communication processing different from normal, triggered by pressing of the switches 441 and 442.

FIG. 20 shows a flowchart of the process of the sensor node 1 described in the program 421 recorded in the ROM 420 of FIG. 17, and in particular, the processes P501, 502, 504 and 505 are described in the sensing program 422. Process P508 is described in the wireless communication program 424, and process P510 is described in the wired communication program 423. In FIG. 20, even if other processes P502 to P510 are being executed by an interrupt from the interrupt control unit 406 that has received a signal from the real-time clock 438, the process P510 is immediately executed and sensing is always performed at a constant cycle. It is possible to do.

The process P501 is started by an interrupt from the interrupt control unit 406, sensed by one or more of the acceleration sensor 435, the temperature sensor 436, and the pulse sensor 437, and records the sensed data in the transmission buffer 415 of the RAM 410. . After the process is completed, the process proceeds to process P502.

Processing P502 determines whether or not the transmission buffer 415 has a capacity for recording the sensed data. When the recording becomes impossible, the process proceeds to process P503, where the data recorded in the transmission buffer 415 is converted into a packet conforming to the wireless protocol and wirelessly transmitted to a predetermined base station. After the process is completed, the process proceeds to process P504. The wireless transmission result (success, failure, etc.) is recorded in the wireless communication state 412. If there is a recordable capacity, the process proceeds to process P506.

Processing P504 compresses the data of the wirelessly transmitted packet by a known compression method and records it in the storage buffer 416. The compression method to be applied is desirably a processing time sufficiently shorter than the interval at which the real-time clock 438 generates a signal when the CPU 401 of the microcomputer 400 executes the processing. Next, in the process P505, if data for one packet capacity is accumulated in the storage buffer 416, it is recorded in the storage 460. If untransmitted data is included, the flag is set to 0; The write destination position in the storage 460 refers to the write address 418 of the RAM 410, and after the writing is completed, the write address 418 is updated to the next address. When the read address 417 and the write address 418 before update are the same and the written flag is 1, there is no untransmitted data to be read, so the read address 417 is also updated at the same time. After the process is completed, the process proceeds to process P506.

Processing P506 compares the read address 417 and the write address 418 recorded in the RAM 410. If the addresses are different, the process proceeds to process P507, and if the addresses are the same, the process proceeds to process P509. That is, it is determined whether there is a packet including untransmitted data. If the read address 417 and the write address 418 are the same, it can be determined that all the packets recorded in the storage 460 have been transmitted.

Processing P507 refers to the wired connection state 413 of the RAM 410. If the wired connection is ON, the process proceeds to process P510, and if it is OFF, the process proceeds to process P508. In process P508, a packet including untransmitted data is read, and if the flag corresponding to the packet is 0, the packet is transmitted wirelessly. When transmission is successful and a packet including untransmitted data exists in the storage 460, reading and wireless transmission are repeated and executed. The position of the packet to be read refers to the read address 417 of the RAM 410. If the wireless transmission fails or there is no packet including untransmitted data in the storage 460, the process P508 proceeds to the process P509. If an interrupt from the interrupt control unit 406 occurs during the execution of the process P508, the process is stopped and the process P501 is started. The process P510 reads a packet including untransmitted data, and transmits the packet by wire if the flag corresponding to the packet is 0. When wired communication is possible and a packet including untransmitted data exists in the storage 460, reading and wired transmission are repeated and executed. The position of the packet to be read refers to the read address 417 of the RAM 410. The process P510 proceeds to the process P509 when wired transmission cannot be performed or when there is no packet including untransmitted data in the storage 460. If an interrupt from the interrupt control unit 406 occurs during the execution of the process P510, the process is stopped and the process P501 is started.

Process P509 stops the clock of the microcomputer 410 and puts it into a low power standby state (sleep state). In the standby state, it is possible to shift to the activated state by an interrupt from the interrupt control units 406 and 407. Therefore, the power consumption can be greatly reduced by performing the intermittent operation in which only the timing necessary for the processing is activated while the time without the necessary processing is set to the standby. However, referring to the wired connection state 413 of the RAM 410, if it is ON, power is supplied from the outside, so there is no need to enter standby.

FIG. 21 shows the process P503 of FIG. 20, and shows in detail the process of wirelessly transmitting the real-time data immediately after measurement by the sensor node 1 to the base station 2. In FIG. 21, it is assumed that communication with the base station 2 cannot be established if wireless transmission fails continuously, empty data is sent with the transmission interval thinned, and an Ack reply is confirmed. Thus, unlike the normal base station search process, it is characterized in that it is confirmed whether the base station 2 is in the vicinity with as low power as possible. The wireless communication process starts from process P520.

In process P521, if the current transmission mode recorded in the wireless communication state 412 of the RAM 410 is the data transmission mode, the process proceeds to process P522, and if it is the scan transmission mode, the process proceeds to process P531. In process P522, the real-time data recorded in the transmission buffer 415 of the RAM 410 is transmitted to the wireless communication unit 431 and wirelessly transmitted to the base station 2.

In process P531, empty data is transmitted to the base station 2. For example, in the case of IEEE 802.15.4, the payload area is set to 0 or 1 byte dummy data only. Transmission of empty data is only for checking the presence or absence of a neighboring base station with Ack, and the amount of data is reduced in order to suppress power consumption as much as possible. In order to further reduce power consumption, the number of transmissions is thinned out here. For example, transmission is performed only once in 10 times.

In process P523, it is determined whether there is an Ack for wireless transmission in processes P522 and P531. If an Ack is received, the transmission is considered successful and the process proceeds to processing 524. If there is no Ack, it is regarded as a transmission failure, and the process proceeds to process P532.

In process P524, the previous transmission result of the wireless communication state 412 of the RAM 410 is regarded as successful wireless transmission. Similarly, in process P532, the previous transmission result of the wireless communication state 412 is determined as wireless transmission failure. In process P525, the continuous transmission failure count recorded in the wireless communication state 412 of the RAM 410 is rewritten to zero. In process P533, the number of consecutive transmission failures recorded in the wireless communication state 412 of the RAM 410 is rewritten to a value that is one greater than the original value.

In process P534, if the number of continuous transmission failures in the wireless communication state 412 exceeds the predetermined number (10 in this example), the process proceeds to process P535, and if not, the process proceeds to process P526. In process P526, the transmission mode of the wireless transmission state 412 of the RAM 410 is set to the data transmission mode. Similarly, in process P535, the transmission mode in the wireless transmission state 412 is set to the scan transmission mode. The wireless communication process is completed in process P527.

FIG. 22 shows in detail the processing for changing the communication setting of the sensor node 1 by operating the switches 441 and 442. In FIG. 22, the communication setting process is activated by interruption only when the switch is pressed and held, and the user 8 can manually set the communication setting of the sensor node 1. If there is no operation for a certain period of time, the setting is not changed. It is characterized by returning to the original. In this embodiment, in the normal display state, it is assumed that the waveform of sensing data, item information, wireless radio wave state, remaining battery level, remaining memory level, etc. are displayed on the LCD of the sensor node. Then, when the user presses the switch 442 for a long time, the mode shifts to the sensor node parameter setting mode. In addition, it is assumed that by pressing the switch 441, the parameter being displayed on the LCD can be changed to the forward feed within the specified effective range.

The communication setting change process is an interrupt by the switches 441 and 442 of the interrupt control unit 406, and starts from process P551. In the process P552, the state of the switch 441 or the switch 442 is continuously detected until the switch is released. In the process P553, if the pressing time of the switches 441 and 442 detected in the process P552 is equal to or longer than a predetermined time (for example, 2 seconds), the process shifts to the process P554, and if it is less than 2 seconds, the process shifts to the process P559. Complete the communication setting change process.

In process P554, all parameters 411 in the RAM 410 are read. At the same time, the effective range and display format specified for each parameter are read from the program 421 in the ROM 420. In process P555, a timer is set. Also, the elapsed time is cleared to zero. When the switch is in a long-pressed state rather than the intention of the user 8 and the communication setting change processing is started by mistake or when it is desired to cancel the processing, the timer is processed without being pressed. This is for interrupting and returning to the normal display. The timer measures the elapsed time by using the function of the real-time clock 438 or by using the interrupt at the time of measurement and counting the number of interrupts.

In process P556, it is detected whether any of the switches 441 and 442 is pressed. In process P557, if the switch 441 is pressed in process P556, the process proceeds to process P560. If not, the process proceeds to process P558. In process P560, the value being displayed in the currently set parameter is updated to forward within the specified effective range. In process P558, if the switch 442 is pressed, the process proceeds to process P561. If not, the process proceeds to process P559.

In process P561, when the currently selected parameter is not a normal parameter but a setting end selection state, the process shifts to process P563 as the setting end. If parameters such as a wireless channel and PANID are selected, the process proceeds to process P562.

In process P562, the value of the selected parameter is determined and recorded in the parameter 411 of the RAM 410, and the process proceeds to the next parameter setting. For example, it is a process of determining the setting of the wireless channel and proceeding to the setting of the PANID. In process P563, the parameter 411 in the RAM 410 is copied to the parameter 461 in the storage 460. That is, when this process is not performed and the setting change process ends due to elapse of a timer or the like, the parameter change is discarded and not reflected.

In process P559, it is detected whether or not the timer has passed a predetermined time (for example, 10 seconds) or more. If it has elapsed, the process proceeds to process P564, and if not, the process proceeds to process P556. This is because it is determined that there is a possibility that the user will perform an operation for the predetermined time.

In process P564, the parameter 461 of the storage 460 is copied to the parameter 411 of the RAM 410. That is, the changed content added to the parameter 411 is discarded. The communication setting change process is completed in process P565.

FIG. 23 shows the process P508 of FIG. 20 in detail, and is a process of reading data recorded in the storage 460 and wirelessly transmitting it. In FIG. 23, when a packet including untransmitted data exists in the storage 460, the process of reading and wirelessly transmitting data is continued until an interrupt is received in response to a signal from the real-time clock 438 or wireless transmission fails. It is characterized by repeating. That is, data can be wirelessly transmitted as fast as possible without affecting the sensing timing.

The storage data wireless transmission process is started from the process P601, the process proceeds to the process P602, and the wireless communication state 412 of the RAM 410 is referred to. If the wireless communication state 412 is successful, the process proceeds to process P603, and a packet including untransmitted data is read from the storage. For the read position, the read address 417 of the RAM 410 is referred to, and only the packet whose corresponding flag is 0 is read. After the process is completed, the process proceeds to process P604.

Process P604 wirelessly transmits the packet read in process P603. After completion of transmission, the process proceeds to process P505 to wait for reception of ACK as a response to transmission. When ACK is received, the process proceeds to process P606, and the next packet whose flag corresponding to the read address 417 of the RAM 410 is 0 The process proceeds to the process P607. If the ACK has not been received, the process proceeds to process P608 to complete the storage data wireless transmission process.

Processing P607 compares the read address 417 and the write address 418 of the RAM 410 for comparison. If the addresses are different, the process proceeds to process P503 to read the next data from the storage. If the addresses are the same, the process proceeds to process P508 to complete the storage data wireless transmission process.

FIG. 24 shows the process P510 of FIG. 20 in detail, and is the process of reading the data recorded in the storage 460 and transmitting it by wire. In FIG. 24, when a packet including untransmitted data exists in the storage 460, the process of reading the data and transmitting it by wire is continued until an interrupt is received in response to a signal from the real-time clock 438 or the USB is disconnected. It is characterized by repeating. That is, it is possible to wire-transmit data as fast as possible without affecting the sensing timing.

The storage data wired transmission process is started from process P701, and the process proceeds to process P702. The process P702 refers to the wired communication state 414 of the RAM 410. If the process P702 is OFF, the process P702 proceeds to the process P706 and starts reading data. If it is ON, the process proceeds to process P703.

Process P703 transmits a communication start request by wire and waits for a response until process P704. This is because even if the USB is connected, there is a possibility that the external device that is the counterpart may not be able to receive correctly by a PC or the like that performs a predetermined receiving operation. Since the process P704 starts wired communication only when there is a response to the communication start request, the process P704 proceeds to process P705. Therefore, since data can be transmitted only to a predetermined PC or the like, unnecessary data transmission can be avoided. If there is no response, the process proceeds to process P713, the wired communication state 414 of the RAM 410 is rewritten to OFF, and the storage data wired transmission process is completed. In process P705, ON is written in the wired communication state 414 of the RAM 410, and the process proceeds to process P706 to start reading data.

Processing P706 reads a packet including untransmitted data from the storage 460. With reference to the read address 417 of the RAM 410, only the packet whose correspondence flag is 1 is read, and the process proceeds to process P707. Process P707 controls DMAC 402 and starts reading the next packet. By starting reading the next packet before proceeding to process P708 and starting wired transmission, wired transmission and packet reading can be executed simultaneously to maximize the data transmission speed.

The process P709 refers to the wired connection state 413 of the RAM 410 after the process P708 is completed. If the connection is cut off halfway, it can be detected because OFF is rewritten to the wired connection state 413 by the interrupt process. If the wired connection state 413 is ON, the read address 417 is updated in process P710, and the process proceeds to process P711. If it is OFF, the process proceeds to process P712 to complete the storage data wired transmission process. In the process P711, the read address 417 and the write address 418 of the RAM 410 are referred to. If they are the same, it is considered that there is no untransmitted data in the storage 460, and the process proceeds to the process P712 to complete the storage data wired transmission process. If they are different, the process proceeds to process P607 to start reading the next data.

FIG. 25 shows the appearance of the cradle 10 of the present embodiment. The cradle is used for connection when performing wired communication between the sensor node and the base station. 25 has terminals 600 to 604 that contact the terminal 470 of the sensor node 1 shown in FIG. 19 and has a shape that covers the upper part of the sensor node 1. Even when connected to the sensor node 1, the side portion And a USB connection terminal 607 that can be connected to a USB port of an external device without interfering with user operations. Since the cradle 2 and the sensor node 1 are fixed by a fixing portion 606 having a claw-like shape, even when a user wearing the sensor node 1 moves or pulls the cable 605, it does not easily come off. . In addition, the upper part in contact with the LCD is opened in a window shape so that the contents of the LCD are not obstructed. In addition, the side portion opposite to the cable 605 has a shape with an open center so as not to hinder the operation of the switches 441 and 442. Therefore, even when the cradle 2 is connected, the user wearing the sensor node 1 can continue daily operations without being disturbed by sensing and various operations.

FIG. 26 shows an external appearance when the sensor node 1 with the cradle 10 connected is worn. In FIG. 26, the cradle 10 is set in the sensor node 1 and the USB connection terminal 607 is connected to the USB port 12 of the personal computer 11, and the current time displayed on the LCD 434 is also displayed during wired communication or charging. It is characterized in that a waveform sensed by a pulse sensor or the like, a symbol indicating that sensing is being performed, and the like can be visually recognized. That is, use of the sensor node 1 by the user 8 is not hindered even if the cradle 10 is connected.

FIG. 27 shows a communication flow when the sensor node 1 and the personal computer 5 perform wired communication in the present embodiment. In FIG. 27, similarly to the wireless communication, the base station 2 performs communication only in the time allocated to the sensor node 1. Therefore, even if the sensor node 1 transmits a communication start request at regular intervals of about 10 seconds, the base station 2 returns a response only within the allocated time. Thereby, it can be judged whether the sensor node 1 is within the allotted time and the connection is established.

When the sensor node 1 is connected to the general-purpose I / F 210 of the base station 2 by a wired connection means such as USB, the sensor node 1 transmits a communication start request 701 to the base station 2. The communication start request 702 cannot start communication because there is no response from the base station 2. When the base station 2 starts an allocation time for wired communication with the sensor node 1 in the process 711, the base station 2 returns a response 704 to the subsequent communication start request 703. Upon receiving the response 704, the sensor node 1 rewrites the wired communication state 414 of the RAM 410 from OFF to ON. As a result, the in-storage unsent data transmission 705 is started. Even after the communication is established, the sensor node 1 transmits a communication start request at intervals of about 10 seconds. The base station transmits behavior index data 710 transmitted from the sensor node to the server.

As shown in FIG. 27, when the response 707 is continuously returned to the communication start request 706, the unsent data transmission in storage 708 is repeated. In the middle of this, when the communication setting allocation time ends in the process 712 of the base station 2, a response to the next communication start request 709 is not returned. In this case, the sensor node 1 regards the unsent data transmission 708 in the storage as a transmission failure, and thereafter returns to the same state as the communication start request 701 again.

DESCRIPTION OF SYMBOLS 1 Sensor node 4 Network 8 User 200 Wireless communication part 203 Nonvolatile memory | storage part 207 Central processing part (CPU)
208 Volatile memory (RAM)
210 General-purpose interface 212 User interface control unit 290 Exercise intensity 291 Exercise amount 302 Central processing unit (CPU)
303 Volatile memory (RAM)
401 Central processing unit (CPU)
402 Direct memory access controller 406, 407 Interrupt control unit 410 Volatile storage unit (RAM)
420 Nonvolatile storage (ROM)
431 Wireless communication unit 433 USB communication unit 435 Acceleration sensor 436 Temperature sensor 437 Pulse sensor 438 Real time clock 441, 442 Switch 445 Power supply switching unit 446 Regulator 450 Antenna 460 Storage 470 Connector

Claims (11)

A network system comprising a plurality of terminals and a base station that communicates with each of the plurality of terminals,
Each of the plurality of terminals
A sensor for acquiring biological information;
A recording device for recording communication settings for transmitting the biological information to the base station;
A communication device that transmits the biological information to the base station at a predetermined interval based on the communication setting,
The base station
A recording device for recording communication settings of each of the plurality of terminals;
A control device that sequentially selects communication settings of each of the plurality of terminals according to time allocated to each of the plurality of terminals;
A network system comprising: a communication device that communicates with the terminal based on the selected communication setting. The network system according to claim 1,
Each of the communication devices of the plurality of terminals does not transmit a signal requesting a network-specific identification ID configured by the base station to the base station using a specific radio frequency band, and is configured by the base station A network system that does not transmit a signal requesting a unique identification ID in the network to the base station. The network system according to claim 1,
The network system includes a first base station and a second base station,
The network system in which the terminal does not change the communication setting even when the terminal moves from the communication area of the first base station to the communication area of the second base station. The network system according to claim 1,
The said control apparatus is a network system which estimates the action state of the person who wears the said terminal based on the said biometric information, and controls the time allocated to each of these terminals based on the said action state. The network system according to claim 4, wherein
A network system that reduces time allocated to the terminal when the control device determines that a person wearing the terminal is absent based on the biological information. The network system according to claim 1,
A server connected to the base station via a network;
The control device transmits the changed communication setting to the server when the communication setting is changed, receives the communication setting of each of the plurality of terminals from the server, and is recorded in the recording device A network system that updates communication settings. The network system according to claim 1,
The communication system includes a network system that includes a radio channel that defines a radio frequency band, a network-specific identification ID configured by the base station, and a network-specific identification ID configured by the base station. A base station connected to a terminal that acquires biological information and transmits the biological information at predetermined intervals based on predetermined communication settings,
A recording device for recording communication settings of each of the plurality of terminals;
A control device that sequentially selects communication settings of each of the plurality of terminals according to time allocated to each of the plurality of terminals;
A base station comprising: a communication device that communicates with the terminal based on the selected communication setting. The base station according to claim 8,
The control device is a base station that estimates a behavior state of a person wearing the terminal based on the biological information and controls a time allocated to each of the plurality of terminals based on the behavior state. In the base station according to claim 9,
The base station that reduces time allocated to the terminal when the control device determines that the person wearing the terminal is absent based on the biological information. The base station according to claim 8,
The communication setting includes a radio channel that defines a radio frequency band, a network-specific identification ID configured by the base station, and a base station that is a unique identification ID within the network configured by the base station.

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