In-vehicle device, control method, and computer program

Abstract

The in-vehicle device is an in-vehicle device mounted on a vehicle, and includes: a communication unit that communicates with an external device and transmits sensor data detected by a sensor mounted on the vehicle to the external device; and a buffer control unit that, on the basis of the wireless communication speed with the external device by the communication unit, determines whether or not to perform a buffer in which the sensor data is stored in the storage unit without being transmitted by the communication unit, and performs a buffer on the basis of the determination result.

Description

Technical Field

[0001] The present disclosure relates to an in-vehicle device, a control method, and a computer program. This application claims priority based on Japanese application No. 2022-148752 filed on September 20, 2022, and all the contents described in the above Japanese application are cited. Background Art

[0002] Systems that collect sensor data from multiple sensors to a server computer (hereinafter referred to as a server) for analysis and use the analysis results for driving assistance are becoming popular. Sensor data is sent from sensors mounted on vehicles and sensors equipped with infrastructure equipment installed on the roadside (hereinafter referred to as infrastructure sensors). In such a system, the vehicle communicates with the server via a wireless base station. Vehicles with wireless communication functions can also communicate directly between vehicles without going through a server (so-called inter-vehicle communication). In inter-vehicle communication, sensor data from a vehicle is sent to other vehicles, or information possessed by a vehicle is sent to other vehicles.

[0003] The following patent document 1 discloses a vehicle-mounted device (vehicle-mounted communication control device) having a function of wirelessly communicating with the outside of the vehicle. The vehicle-mounted communication control device communicates with a content provider outside the vehicle. The vehicle-mounted communication control device can reproduce the content without interruption even in a section where the radio wave environment of the vehicle's scheduled driving route is poor and streaming content cannot be fully downloaded. Therefore, the vehicle-mounted communication control device of patent document 1 performs buffering for the reproduction of downloaded data. The vehicle-mounted communication control device calculates the amount of data that can be buffered in consideration of the vehicle's driving speed and determines whether the download is possible. Prior art literature Patent Literature

[0004] Patent Document 1: Japanese Patent Application Publication No. 2003-61149. Summary of the invention

[0005] An aspect of the present disclosure relates to a vehicle-mounted device that is mounted on a vehicle, and includes: a communication unit that communicates with an external device and sends sensor data detected by a sensor mounted on the vehicle to the external device; and a buffer control unit that determines whether to perform buffering by storing the sensor data in a storage unit and not sending it through the communication unit based on a wireless communication speed between the communication unit and the external device, and performs buffering based on the determination result. BRIEF DESCRIPTION OF THE DRAWINGS

[0006] Figure 1 It is a schematic diagram showing a usage form of the vehicle-mounted device according to the embodiment of the present disclosure. Figure 2 It is shown Figure 1 The block diagram of the hardware structure of the vehicle-mounted device is shown. Figure 3 It is shown Figure 2 The block diagram of the hardware structure of the vehicle gateway is shown. Figure 4 It is shown Figure 1 A block diagram of the hardware structure of the first server is shown. Figure 5 It is shown Figure 1 A block diagram of the hardware structure of the second server is shown. Figure 6 It is shown Figure 2 The block diagram of the functional structure of the vehicle gateway is shown. Figure 7 This is a diagram showing a state where a planned travel route of a vehicle is displayed on a communication performance map. Figure 8 is a flowchart showing a process performed by the in-vehicle gateway. Fig. 9 is a flowchart illustrating a process performed by the first server. Fig.10 is a flowchart illustrating processing performed by the second server. DETAILED DESCRIPTION

[0007] [Problems to be Solved by the Present Disclosure] When the vehicle is in an environment where the wireless communication speed is low, in order to send the data normally, it is considered to reduce the quality of the data and reduce the data size for sending. However, if the sent data does not meet the quality required by the server's service, the sent data cannot be properly used. In this case, the data transmission itself is wasted.

[0008] The vehicle-mounted communication control device disclosed in Patent Document 1 is related to downloading of streaming data, and therefore cannot solve the above-mentioned problem related to transmission (ie, uploading) of data.

[0009] Therefore, an object of the present disclosure is to provide an in-vehicle device, a control method, and a computer program that can transmit data to an external device without reducing the quality of the transmitted data even when the vehicle is traveling in an environment where the wireless communication speed is low.

[0010] [Effects of the present disclosure] According to the present disclosure, it is possible to provide an in-vehicle device, a control method, and a computer program that can transmit data to an external device without reducing the quality of the transmitted data even when the vehicle is traveling in an environment where the wireless communication speed is low.

[0011] [Description of Embodiments of the Present Disclosure] The contents of the embodiments of the present disclosure are listed and described. At least a part of the embodiments described below may be arbitrarily combined.

[0012] (1) The vehicle-mounted device according to the first aspect of the present disclosure is a vehicle-mounted device mounted on a vehicle, comprising: a communication unit that communicates with an external device and transmits sensor data detected by a sensor mounted on the vehicle to the external device; and a buffer control unit that determines whether to perform buffering by storing the sensor data in a storage unit instead of transmitting it through the communication unit based on the wireless communication speed between the communication unit and the external device, and performs buffering based on the determination result. As a result, the vehicle-mounted device can transmit the transmitted data to the external device without reducing the quality of the transmitted data even when the vehicle is traveling in an environment where the wireless communication speed is low. Therefore, the external device can maintain service.

[0013] (2) In the above (1), when a low-speed communication state in which the wireless communication speed is less than a predetermined value occurs within a predetermined range on a planned driving route of the vehicle, the buffering control unit may determine that buffering is to be performed, and perform buffering while the vehicle is traveling within the predetermined range. In this way, necessary and sufficient buffering can be performed.

[0014] (3) In the above (2), the communication unit may further receive information indicating required data quality transmitted from an external device, the required data quality indicating the data volume per unit time of the sensor data transmitted from the vehicle-mounted device to the external device, the buffer control unit calculates a predicted time for the vehicle to travel within a predetermined range, calculates a storage volume required for buffering using the predicted time and the required data quality, and determines whether the calculated storage volume can be secured in the storage unit. In this way, it is possible to effectively determine whether buffering is possible.

[0015] (4) In the above (3), the buffer control unit may receive a signal that the vehicle-mounted device has approached a predetermined range and is within a predetermined distance, calculate the predicted time, calculate the storage capacity, and determine whether the storage capacity can be secured in the storage unit. In this way, it is possible to determine whether buffering is possible with high accuracy.

[0016] (5) In (3) or (4), if the storage capacity cannot be ensured, the buffer control unit may cause the communication unit to send information indicating that the sensor data cannot be sent to the external device. This eliminates the need for the external device to wait for sensor data from the vehicle-mounted sensor, thereby avoiding waste of resources.

[0017] (6) In any of the above (3) to (5), the communication unit may further receive information indicating an allowable delay time transmitted from an external device, and if the predicted time is greater than the allowable delay time, the buffer control unit may cause the communication unit to transmit information indicating that the sensor data cannot be transmitted to the external device. This eliminates the need for the external device to wait for sensor data from the vehicle-mounted sensor, thereby avoiding waste of resources.

[0018] (7) In any of the above (1) to (6), the communication unit may further receive a communication performance map from outside the vehicle-mounted device, and information indicating a road and information indicating a performance speed of wireless communication on the road are included in the communication performance map in correspondence with each other. The buffer control unit may determine information indicating a road corresponding to the planned driving route from the information indicating a road included in the communication performance map, and use the information indicating the performance speed corresponding to the determined information as the information indicating the wireless communication speed to determine whether to perform buffering. In this way, the vehicle-mounted device can easily determine whether buffering is required.

[0019] (8) In any one of (1) to (7), the buffer control unit may cause the communication unit to transmit the sensor data stored in the storage unit after buffering to the external device if buffering is no longer necessary. This allows the in-vehicle device to transmit the buffered sensor data to the external device without wasting the buffered sensor data.

[0020] (9) The control method according to the second aspect of the present disclosure is a control method for a vehicle-mounted device mounted on a vehicle, comprising: a communication step of communicating with an external device and sending sensor data detected by a sensor mounted on the vehicle to the external device; and a buffer control step of determining whether to perform buffering to store the sensor data in a storage unit instead of sending it through a communication unit based on the wireless communication speed between the external device and the communication step, and performing buffering based on the determination result. Thus, the vehicle-mounted device can send data to the external device without reducing the quality of the data even when the vehicle is traveling in an environment where the wireless communication speed is low. Therefore, the external device can maintain service.

[0021] (10) The computer program according to the third aspect of the present disclosure enables a computer mounted on a vehicle to implement the following functions: a communication function for communicating with an external device and transmitting sensor data detected by a sensor mounted on the vehicle to the external device; and a buffer control function for determining whether to perform buffering to store the sensor data in a storage unit instead of transmitting the sensor data through the communication function based on the wireless communication speed between the vehicle and the external device based on the communication function, and performing buffering based on the determination result. Thus, even if the vehicle is traveling in an environment where the wireless communication speed is low, the computer can transmit the transmitted data to the external device without reducing the quality of the transmitted data. Therefore, the external device can maintain service.

[0022] The present invention can be implemented not only as an on-board device having such a characteristic processing unit, but also as a control method having the characteristic processing as a step, or as a program for causing a computer to execute the step. In addition, it can be implemented as a semiconductor integrated circuit that implements a part or all of the on-board device, or as a service providing system including the on-board device.

[0023] [Details of the embodiments of the present disclosure] In the following embodiments, the same reference numerals are used for the same components. Their names and functions are also the same. Therefore, their detailed description will not be repeated.

[0024] (Overall structure) Reference Figure 1 The vehicle-mounted device 100 according to the embodiment of the present disclosure is mounted on a vehicle 102. The vehicle-mounted device 100 receives a request from a first server 104 that provides a service and uploads data that can be used for the service. The service provided by the first server 104 is, for example, a remote monitoring service (for example, monitoring of traffic conditions or monitoring of the state inside the vehicle (monitoring of the driver's state, etc.)). The service provided by the first server 104 may also be a service that provides information to the vehicle for assisting the driving of the vehicle. As described later, the uploaded data is sensor data obtained by a vehicle-mounted sensor mounted on the vehicle 102. In addition, another vehicle 112 equipped with a vehicle-mounted device similar to the vehicle 102 is also traveling. The vehicle 102 and the other vehicles 112 send performance data of wireless communication to a second server 106 that generates, manages, and distributes a communication performance map. As described later, the communication performance map is a road map divided into a plurality of areas (for example, rectangular areas) (hereinafter, the divided areas are referred to as "areas"), and each area corresponds to the communication speed and signal strength of wireless communication in the area. The second server 106 receives a request from the in-vehicle device 100 and transmits a communication record map to the in-vehicle device 100 .

[0025] The communication between the vehicle-mounted device 100, the vehicle-mounted devices of other vehicles 112 (not shown), the first server 104, and the second server 106 is performed via the base station 108. The base station 108 provides, for example, mobile communication services based on 4G (fourth generation) lines and 5G (fifth generation) lines. The base station 108 is connected to the network 110. The vehicle-mounted device 100 of the vehicle 102 and the vehicle-mounted devices of other vehicles 112 have a communication function based on the communication standards (4G lines and 5G lines, etc.) served by the base station 108.

[0026] In addition, the first server 104 also receives sensor data from infrastructure sensors 114 fixedly installed on the roadside (i.e., the road (including intersections) and its surroundings). The infrastructure sensor 114 is, for example, an image sensor (digital surveillance camera, etc.), a radar (millimeter wave radar, etc.), or a laser sensor (Li DAR (Light Detection and Ranging), etc.). The infrastructure sensor has a communication function with the base station 108, and transmits the acquired sensor data to the first server 104 via the base station 108 and the network 110.

[0027] The vehicle 102, other vehicles 112, and pedestrians 900 are detection targets of the infrastructure sensor 114. The vehicle 102 and other vehicles 112 are also equipped with vehicle-mounted sensors. The other vehicles 112 and pedestrians 900 are detection targets of the vehicle-mounted sensors installed on the vehicle 102. The vehicle 102 and pedestrians 900 are detection targets of the vehicle-mounted sensors installed on the other vehicles 112.

[0028] Sensor data acquired by the vehicle-mounted sensors of the vehicle 102 are transmitted to the first server 104 via the base station 108 and the network 110. The first server 104 analyzes the sensor data received from the vehicle 102 and the infrastructure sensors 114 and uses them for services.

[0029] exist Figure 1 1 shows a base station 108, a vehicle 102 equipped with a vehicle-mounted device 100, and another vehicle 112. However, this is only an example. Usually, a plurality of base stations are provided. A plurality of vehicles uploading sensor data to the first server 104 are traveling, and a plurality of other vehicles 112 uploading communication performance data to the second server 106 are traveling. There may also be a vehicle without a vehicle-mounted device. A vehicle without a vehicle-mounted device is detected as a dynamic object.

[0030] (Hardware structure of vehicle-mounted device) Reference Figure 2 , shows an example of a hardware configuration of a vehicle-mounted device 100 mounted on a vehicle 102. The vehicle-mounted device 100 includes a communication unit 120, a vehicle-mounted gateway 122, a vehicle-mounted sensor 124, a vehicle state management unit 126, a driving control unit 128, and a bus 132.

[0031] The communication unit 120 performs wireless communication with an external device of the vehicle 102 (for example, communication with the first server 104 or the like via the base station 108). The communication unit 120 includes an IC (Integrated Circuit) for performing modulation and multiplexing used in wireless communication, an antenna for transmitting and receiving radio waves of a specified frequency, and an RF (Radio Frequency) circuit. The communication unit 120 also has a communication function with a global satellite positioning system (GNSS: Global Navigation Satellite System) such as GPS (Global Positioning System). The communication unit 120 may also have a communication function such as Wi-Fi.

[0032] The vehicle-mounted gateway 122 plays a role in coupling the communication function (specifically, the communication specification) outside the vehicle and the communication function (communication specification) inside the vehicle (for example, communication protocol conversion, etc.). In addition, as described later, when uploading data to the first server 104, the vehicle-mounted gateway 122 performs control of buffering the uploaded data according to the state of the wireless communication environment.

[0033] The bus 132 has a communication function within the vehicle, and the vehicle gateway 122, the vehicle sensor 124, the vehicle state management unit 126, and the driving control unit 128 communicate with each other (ie, exchange data) via the bus 132. For example, the bus 132 uses a CAN (Controller Area Network).

[0034] The vehicle-mounted sensor 124 is mounted on the vehicle 102, and includes sensors for obtaining information outside the vehicle 102 (video image shooting devices (for example, digital cameras (CCD (Charge-Coupled Device) cameras or CMOS (Complementary Metal-Oxide Semiconductor) cameras)), laser sensors (for example, LiDAR), etc.) and sensors for obtaining information about the vehicle itself (for example, acceleration sensors and load sensors). The vehicle-mounted sensor 124 obtains information within the detection range (the shooting range in the case of a camera) and outputs it as sensor data. If it is a digital camera, digital image data is output. The detection signal (i.e., analog or digital signal) of the vehicle-mounted sensor 124 is output as digital data to the bus 132 via the I / F unit (not shown) and sent to the vehicle-mounted gateway 122.

[0035] The vehicle state management unit 126 manages the state (eg, position, travel speed, acceleration, and travel direction) of the vehicle 102. The position can be acquired, for example, by GPS. The travel speed, acceleration, and travel direction can be calculated, for example, by time-series position information and corresponding time information.

[0036] The driving control unit 128 controls the driving of the vehicle 102. The driving control unit 128 is, for example, an automatic driving ECU (Electronic Control Unit). For example, the driving control unit 128 obtains sensor data from the on-board sensor 124, analyzes it to understand the surrounding conditions of the vehicle 102, and controls mechanisms related to automatic driving (i.e., mechanisms such as the engine, transmission, steering, and brakes). In addition, the vehicle 102 is not limited to a vehicle with an automatic driving function. If the vehicle 102 does not have an automatic driving function, the vehicle 102 does not include the driving control unit 128.

[0037] (Hardware structure of vehicle gateway) Reference Figure 3 The in-vehicle gateway 122 includes a control unit 140 and a memory 142. The control unit 140 is configured to include a CPU (central processing unit) and controls the memory 142. The memory 142 is, for example, a rewritable non-volatile semiconductor memory, which stores a computer program (hereinafter referred to as a program) executed by the control unit 140. The memory 142 provides a work area for the program executed by the control unit 140. The control unit 140 directly obtains the data of the processing object from the communication unit 120, and obtains the data of the processing object from outside the communication unit 120 via the bus 132. The control unit 140 appropriately stores the data received from the communication unit 120 and the data received via the bus 132 in the memory 142. The control unit 140 stores the processing results in the memory 142 and outputs them to the bus 132.

[0038] (Hardware structure of the first server) Reference Figure 4 The first server 104 includes a control unit 150 for controlling each part, a memory 152 for storing data, a communication unit 154 for communication, and a bus 156 for exchanging data between the parts. The control unit 150 is configured to include a CPU, and realizes the functions described below by controlling each part. The memory 152 includes a rewritable semiconductor non-volatile memory and a large-capacity storage device such as a hard disk drive. The communication unit 154 receives sensor data uploaded from the vehicle-mounted device 100 and the infrastructure sensor 114 via the base station 108. The data received by the communication unit 154 is sent to the memory 152 and stored. As a result, the first server 104 can perform the specified service.

[0039] (Hardware structure of the second server) Reference Figure 5 , the second server 106 is configured in the same manner as the first server 104. That is, the second server 106 includes a control unit 160 for controlling each unit, a memory 162 for storing data, a communication unit 164 for communicating, and a bus 166 for exchanging data between the units. The control unit 160 is configured to include a CPU, and realizes the functions described below by controlling each unit. The memory 162 includes a rewritable semiconductor non-volatile memory and a large-capacity storage device such as a hard disk drive. The communication unit 164 receives communication performance data uploaded from a vehicle-mounted device mounted on another vehicle 112 via the base station 108. The data received by the communication unit 164 is sent to the memory 162 and stored. As a result, the second server 106 can generate and manage a communication performance map, and read out the communication performance map from the memory 162 in response to an external commission and distribute it.

[0040] (Functional structure of vehicle gateway) The functions of the vehicle gateway 122 involved in the present disclosure are described. Figure 6 The in-vehicle gateway 122 includes a communication performance map information DB (Database) 200 , a path calculation unit 202 , a buffer control unit 206 , a communication performance recording unit 208 , a communication performance sending unit 210 , and a communication performance acquiring unit 212 . Figure 6 Shows Figure 2 , Figure 4 and Figure 5 The hardware structure shown is part of the CAN204. Figure 2 The bus 132 shown, the driving unit 214 corresponds to Figure 2 The vehicle state management unit 126 and the driving control unit 128 are shown. Figure 4 As shown in the communication unit 154. Regarding the second server 106, Figure 5 The communication unit 164 shown in FIG. 1 also shows communication performance map information 230, a communication performance sending unit 232, and a communication performance obtaining unit 234 related to the functions of the vehicle gateway 122. The communication performance map information DB 200 is stored in the memory 142 (see FIG. 142 ) of the vehicle gateway 122. Figure 3 ) is implemented. Other functions of the vehicle gateway 122 are implemented by the control unit 140 and the memory 142 (see Figure 3 The communication performance map information DB 200 stores a communication performance map. The communication performance map is a communication performance map that the in-vehicle gateway 122 requests from the second server 106 via the communication unit 120 and receives from the second server 106 .

[0041] The route calculation unit 202 calculates the planned driving route of the vehicle 102 equipped with the vehicle-mounted device 100. The planned driving route of the vehicle 102 is, for example, calculated by the car navigation system after receiving the destination set for the car navigation system installed in the vehicle 102. The car navigation system can calculate the planned driving route by referring to the road map using the set destination and the current position of the vehicle 102 that can be obtained from the GPS. The route calculation unit 202 obtains the planned driving route calculated by the car navigation system from the car navigation system. The route calculation unit 202 may also obtain the planned driving route calculated by the car navigation system independently from the vehicle state management unit 126 (see Figure 2 ) obtains the position information of the vehicle 102, and calculates the planned driving route of the vehicle 102 in the same manner as the car navigation system. The route calculation unit 202 outputs the information of the calculated planned driving route to the buffer control unit 206.

[0042] In addition, the route calculation unit 202 requests the communication performance acquisition unit 212 to transmit the information of the planned driving route. The communication performance acquisition unit 212 receives the request from the route calculation unit 202 and transmits the information of the planned driving route to the second server 106 (specifically, the communication performance transmission unit 232) via the communication unit 120. For example, referring to Figure 7 The communication performance map divides the road map into a plurality of regions, and makes each region correspond to the communication speed and signal strength of wireless communication in the region. For example, the communication speed and signal strength of each region are representative values ​​(e.g., average values) obtained by statistically processing the communication performance data received from the vehicle-mounted devices of vehicles traveling in the region in the same time period. The communication performance map information 230 of the second server 106 includes, for example, a communication performance map for each time period, which is stored in the memory 162 (see Figure 5 ).like Figure 7 As shown by the dashed arrow, when the planned driving route from the current position of the vehicle 102 to the destination A is determined, the communication performance sending unit 232 of the second server 106 reads the communication performance map related to the area including at least the dashed arrow from the communication performance map information 230. The communication performance sending unit 232 sends the communication performance map read from the communication performance map information 230 to the vehicle 102 (specifically, the vehicle-mounted device 100) via the communication unit 164. The communication performance map sent from the second server 106 to the vehicle 102 is received by the communication performance acquisition unit 212 via the communication unit 120 and stored in the communication performance map information DB 200. In addition, the communication performance sending unit 232 of the second server 106 also sends the communication performance map to the vehicle-mounted device 240 mounted on a vehicle other than the vehicle 102, similarly to sending the communication performance map to the vehicle-mounted device 100.

[0043] The buffer control unit 206 reads the communication performance map from the communication performance map information DB 200, and determines whether the planned driving route input from the route calculation unit 202 includes an area where the wireless communication speed is low. For example, the buffer control unit 206 compares the wireless communication speed obtained from the communication performance map with a predetermined threshold value, determines an area where the wireless communication speed is ≤ the threshold value, and determines whether the determined area overlaps with the planned driving route. In the case of overlap, the overlapping portion on the planned driving route is determined as a predetermined range for buffering described later. Figure 7 For example, in the two areas with diagonal lines (i.e., the low-speed communication area 220 and the low-speed communication area 222), it is set that the wireless communication speed is less than or equal to the threshold value. In this case, the buffer controller 206 determines the dotted line portion included in the low-speed communication area 220 and the low-speed communication area 222 as the prescribed range to be buffered. When the prescribed range is determined, the path calculation unit 202 outputs information indicating the prescribed range to the buffer control unit 206. In addition, in the case where only the communication performance map related to the area including the dotted arrow is transmitted from the second server 106, it is not necessary to determine whether the area where the wireless communication speed is less than or equal to the threshold value overlaps with the scheduled driving route. In addition, in the case where the communication performance map information DB 200 stores the communication performance map for each time period, the buffer control unit 206 can determine whether the area determined as described above overlaps with the scheduled driving route, and whether the time period as the low-speed area overlaps with the time period when the vehicle 102 travels on the scheduled driving route.

[0044] In addition, the communication performance recording unit 208 combines the communication results (e.g., communication speed and signal strength) of the communication unit 120 and the information (e.g., vehicle status and vehicle position information) that can be obtained from the CAN 204, and records them as communication performance data. The communication performance data recorded by the communication performance recording unit 208 is transmitted from the communication performance transmitting unit 210 to the second server 106 via the communication unit 120. The communication performance data transmitted to the second server 106 is received by the communication performance obtaining unit 234 via the communication unit 164 and stored as the communication performance map information 230. In addition, the communication performance data recorded by the communication performance recording unit 208 is also stored in the communication performance map information DB 200. Therefore, the communication results for each location (i.e., area) and time period and the information recording the status of the vehicle 102 at that time can be included in the communication performance map information DB 200. Furthermore, the communication record acquisition unit 234 of the second server 106 also receives communication record data from an in-vehicle device 240 mounted on a vehicle other than the vehicle 102 , and stores the received communication record data as the communication record map information 230 .

[0045] The buffer control unit 206 receives sensor data output from the vehicle-mounted sensor 124 mounted on the vehicle 102 and transmitted via the CAN 204. If the predetermined range cannot be determined, the buffer control unit 206 transmits the input sensor data to the first server 104 via the communication unit 120. The transmitted sensor data is received by the communication unit 154 of the first server 104. In addition, the communication unit 154 of the first server 104 transmits a sensor data transmission request to the vehicle-mounted device 100 in advance (see the following description). Fig. 9 Step 400 of the embodiment of the present invention. For example, the first server 104 sends a transmission request including information indicating the data quality required for the service (hereinafter referred to as the required data quality) and the allowable delay time to the vehicle-mounted device 100. The buffer control unit 206 sends the sensor data that satisfies the required data quality and the allowable delay to the first server 104. The required data quality may, for example, indicate the data capacity per unit time of the sensor data transmitted from the vehicle-mounted device 100 to the first server 104. The required data quality may be specified, for example, by the resolution and frame rate of the sensor data. For example, if the vehicle-mounted sensor 124 is a camera that outputs dynamic image data and can set a plurality of shooting conditions (such as the resolution and frame rate of the output data), the buffer control unit 206 sets the shooting conditions of the vehicle-mounted sensor 124 so as to satisfy the required data quality. Whether the allowable delay is satisfied can be determined, for example, by whether the time required from the generation of the sensor data in the vehicle 102 (i.e., output from the vehicle-mounted sensor 124) to the reception by the first server 104 is less than the allowable delay time. As described later, when the sensor data is buffered, a determination is made based on whether the time including the buffering time is equal to or less than the allowable delay time.

[0046] The buffer control unit 206 includes a buffer area (not shown). The buffer area is a storage area that is secured in order to store sensor data output from the vehicle-mounted sensor 124 in the buffer described later. Figure 3 The buffer control unit 206 stores (i.e., buffers) the input sensor data in the buffer area without sending it to the first server 104 once the prescribed range is determined. The buffer control unit 206 performs buffering while the vehicle 102 is traveling in the prescribed range. Thereafter, when the vehicle 102 completes traveling in the prescribed range, the buffer controller 206 sends the sensor data buffered in the buffer area to the first server 104 (hereinafter referred to as collective transmission). Subsequently, the buffer controller 206 sends the sensor data newly input via the CAN 204 to the first server 104 as described above.

[0047] In order to buffer the sensor data while the vehicle 102 is traveling within the prescribed range, it is necessary to ensure an appropriate storage capacity as a buffer area in the memory 142. Therefore, the buffer control unit 206 predicts the time required for the vehicle 102 to travel within the prescribed range, calculates the capacity of the buffer area (hereinafter also referred to as the buffer capacity) based on the predicted time (hereinafter referred to as the predicted time) and the required data quality, and ensures the calculated capacity in the memory 142. For example, the buffer control unit 206 calculates the distance of the prescribed range based on the information indicating the prescribed range, and obtains the information from the driving unit 214 (specifically, the vehicle state management unit 126 (see Figure 2 )) obtains the travel speed of the vehicle 102, and calculates the predicted time by dividing the distance of the specified range by the travel speed. For example, the buffer control unit 206 calculates the lower limit value of the buffer capacity by multiplying the frame rate (i.e., the number of frames per second), the resolution of one frame (i.e., the number of pixels per frame), the data size of one pixel (e.g., in bytes), and the predicted time in seconds. In addition, if the buffer area of ​​the calculated capacity cannot be ensured, buffering is not performed. In this case, for example, the buffer control unit 206 notifies the first server 104 that buffering cannot be performed. As a result, the first server 104 that has requested the upload of sensor data can allocate the resources used for this to other processing without waiting for sensor data that cannot be received.

[0048] In addition, as described above, the sensor data sent in batches can also meet the allowable delay time. If the sensor data stored in the buffer area does not meet the allowable delay time, the buffer control unit 206 does not send the data in batches. In this case, the buffer control unit 206 also notifies the first server 104 that buffering is not possible. As a result, the first server 104 that requested the upload of the sensor data can allocate the resources used for this to other processing without waiting for the sensor data that cannot be received.

[0049] As described above, the vehicle-mounted gateway 122 determines whether to perform buffering so that the sensor data is stored in the memory 142 without being sent, based on the wireless communication speed with the first server 104 via the communication unit 120 that sends the sensor data of the vehicle-mounted sensor 124, and performs buffering based on the determination result. That is, when the planned driving route of the vehicle-mounted device 100 includes a prescribed range that becomes a low-speed communication state, the vehicle-mounted gateway 122 stores the sensor data in the memory 142 (see Figure 3) ensures storage capacity for buffering, and buffers sensor data while the vehicle 102 travels within a specified range. Thereafter, when the vehicle 102 passes through a specified range that becomes a low-speed communication state, the vehicle-mounted gateway 122 sends the cached sensor data in a centralized manner. Therefore, even if the vehicle 102 travels in an environment where the wireless communication speed is low, the vehicle-mounted device 100 can send the sensor data to the first server 104 without reducing the quality of the sent sensor data. Therefore, the first server 104 can maintain service. In addition, by centrally sending the buffered sensor data, the vehicle-mounted device 100 can send the buffered sensor data to the first server 104 without wasting it. In addition, the planned driving route can also be calculated by an external device of the vehicle 102 (for example, a server that receives a request from the vehicle-mounted device 100) and sent from the external device to the vehicle-mounted device 100.

[0050] As described above, when a low-speed communication state in which the wireless communication speed is less than a predetermined value occurs in a predetermined range on the planned travel route, the buffering control unit 206 determines to perform buffering, and performs buffering while the vehicle 102 travels in the predetermined range. Thus, the vehicle-mounted device 100 can perform necessary and sufficient buffering of sensor data.

[0051] As described above, the vehicle-mounted device 100 receives the information indicating the required data quality transmitted from the first server 104 via the communication unit 120. Furthermore, the buffer control unit 206 calculates the predicted time for the vehicle 102 to travel within the prescribed range, and uses the predicted time and the required data quality to determine whether the buffer capacity required for buffering can be secured in the memory 142. When the storage capacity required for buffering can be secured in the memory 142, the buffer control unit 206 secures the storage capacity in the memory 142. In this way, it is possible to efficiently determine whether buffering is possible.

[0052] As described above, the vehicle-mounted device 100 receives the communication performance map from the second server 106 via the communication unit 120. Furthermore, the buffer control unit 206 determines the road corresponding to the planned driving route from the roads included in the communication performance map, and uses the performance speed corresponding to the determined road as the wireless communication speed to determine whether to perform buffering. In this way, the vehicle-mounted device 100 can easily determine whether buffering is required.

[0053] (Actions of the vehicle gateway) Reference Figure 8 Regarding the operation of the vehicle gateway 122, refer to Figure 6 The functions shown are explained. Figure 8 The processing shown is performed by the control unit 140 (see Figure 3 ) is realized by reading a predetermined program from the memory 142 and executing it. It is assumed that a request for sending sensor data is sent from the first server 104 to the vehicle-mounted device 100 in advance.

[0054] Reference Figure 8 In step 300, the control unit 140 sends information indicating the planned driving route to the second server 106, requesting the transmission of the communication performance map. The request is made, for example, by adding a predetermined request code to the information indicating the planned driving route and transmitting it. As described above, the vehicle-mounted gateway 122 obtains the driving route from, for example, a car navigation system installed in the vehicle 102. After that, the control moves to step 302.

[0055] In step 302, the control unit 140 receives a communication performance map from the second server 106. As described above, the received communication performance map includes the transmitted scheduled driving route. The control unit 140 stores the received communication performance map in the communication performance map information DB 200 (see Figure 6 ). Afterwards, control moves to step 304.

[0056] In step 304, the control unit 140 determines whether there is a low-speed communication area on the planned driving route. Specifically, the control unit 140 determines whether the communication performance map received in step 302 includes an area where the communication speed is below the threshold, and if so, determines whether the planned driving route overlaps with the area. In the case of an overlap, the control unit 140 determines the overlapping portion (i.e., a specified range). That is, in the case of determining the specified range, it is determined that there is a low-speed communication area, and the control moves to step 306. Otherwise (i.e., in the case of not determining the specified range), the control moves to step 328. The processing of step 304 corresponds to Figure 6 The functions of the buffer control unit 206 are shown.

[0057] In step 306, the control unit 140 determines whether the vehicle 102 has approached the low-speed communication area (i.e., the prescribed range on the scheduled driving path determined in step 304). If it is determined to be approaching, the control moves to step 310. Otherwise, the control moves to step 308. Approaching the low-speed communication area means that the distance from the vehicle 102 to the prescribed range is less than the prescribed distance. The prescribed distance can be set to a value in the range of 100m to 10m, for example.

[0058] In step 308, the control unit 140 transmits the sensor data input to the communication performance map information DB 200 to the first server 104 via the communication unit 120. This corresponds to Figure 6 The function of the buffer control unit 206 is shown. After that, the control returns to step 306 and the above-mentioned processing is repeated.

[0059] If the vehicle 102 approaches the low-speed communication area (i.e., the prescribed range), the control unit 140 calculates the storage capacity required for buffering the sensor data in step 310. As described above, regarding the buffer control unit 206, the control unit 140 calculates the required capacity of the buffer area based on the required data quality and the time required for traveling in the prescribed range (i.e., the predicted time). After that, the control moves to step 312. In this way, by calculating the buffer capacity when the vehicle 102 has approached the low-speed communication area (i.e., the prescribed range), it is possible to determine whether buffering is possible with higher accuracy than calculating the buffer capacity when the vehicle 102 is traveling in a place far from the low-speed communication area. The empty capacity of the memory 142 for securing the buffer area changes during the travel of the vehicle 102. Therefore, if the empty capacity of the memory 142 when the vehicle 102 has approached the low-speed communication area is smaller than the empty capacity when the vehicle 102 is traveling in a place far from the low-speed communication area, the buffer capacity calculated when traveling in the far place cannot be secured, and there is a possibility that the buffering cannot be performed.

[0060] In step 312, the control unit 140 determines whether the buffer capacity calculated in step 310 can be secured in the memory 142. This process corresponds to the above Figure 6 If it is determined that the buffering can be ensured, the control proceeds to step 314. Otherwise, the control proceeds to step 324.

[0061] In step 314, the control unit 140 determines whether the buffered sensor data satisfies the allowable delay. Figure 6 If it is determined that the allowable delay is satisfied, the control proceeds to step 316. Otherwise, the control proceeds to step 324.

[0062] In step 316, the control unit 140 determines whether the vehicle 102 has started traveling in the low-speed communication area (i.e., a predetermined range) and whether it is currently traveling in the low-speed communication area. If it is determined that the vehicle 102 is traveling, the control moves to step 318. Otherwise (i.e., if the vehicle 102 has passed the low-speed communication area), the control moves to step 320.

[0063] In step 318, the control unit 140 buffers the sensor data output from the vehicle-mounted sensor 124. That is, the control unit 140 does not send the sensor data output from the vehicle-mounted sensor 124 to the first server 104, but stores it in the buffer area of ​​the buffer control unit 206 (specifically, Figure 6 The control then returns to step 316. At this time, the sensor data is stored in a time series, that is, in a manner that enables the time sequence in which the sensor data is generated to be discerned (for example, with the addition of time information).

[0064] If the result of determination in step 316 is "No", that is, if the vehicle 102 has passed through the low-speed communication area, in step 320, the control unit 140 reads the sensor data stored in the buffer area of ​​the buffer control unit 206, and collectively transmits the sensor data to the first server 104 via the communication unit 120. In addition, collective transmission means that all the sensor data stored in the buffer area of ​​the buffer control unit 206 are transmitted before the new sensor data output from the vehicle-mounted sensor 124 is transmitted to the first server 104. After that, the control moves to step 322.

[0065] In step 322, the control unit 140 determines whether there is a low-speed communication area in which the vehicle 102 has not traveled in the low-speed communication area (i.e., the prescribed range) detected in step 304. Since multiple low-speed communication areas can be detected in step 304, this is a process for dealing with this situation. If it is determined that there is a low-speed communication area in which the vehicle 102 has not traveled, the control returns to step 306. Otherwise, the control moves to step 330.

[0066] If the determination result of either step 312 or step 314 is negative, then in step 324 , the control unit 140 transmits information indicating that the sensor data cannot be transmitted to the first server 104 . Thereafter, the control proceeds to step 326 .

[0067] In step 326, similarly to step 316, the control unit 140 determines whether the vehicle 102 has started traveling in the low-speed communication area and whether it is currently traveling in the low-speed communication area. Step 326 is repeated until the determination is "No" (i.e., until the vehicle 102 passes through the low-speed communication area). Therefore, during this period, the sensor data is not sent to the first server 104, nor is it buffered. In the case of "No", the control moves to step 322.

[0068] If the determination result of step 304 is negative (ie, there is no low-speed communication area on the planned travel route), in step 328 , the control unit 140 transmits the sensor data output from the vehicle-mounted sensor 124 to the first server 104 via the communication unit 120 . Thereafter, control proceeds to step 330 .

[0069] In step 330, the control unit 140 determines whether the vehicle 102 has completed the travel of the scheduled travel route (for example, has reached the destination). Figure 7 If it is determined that the driving is completed, the program ends. Otherwise, the control returns to step 328. In addition, the control unit 140 may also determine that the program ends when receiving a notification from the first server 104 that the sensor data does not need to be sent.

[0070] For example, if there is no low-speed communication area on the scheduled travel route (the result of determination in step 304 is "No"), steps 328 and 330 are repeated while the vehicle 102 travels on the scheduled travel route. On the other hand, if there is a low-speed communication area on the scheduled travel route (the result of determination in step 304 is "Yes"), the vehicle 102 performs buffering if possible while traveling in each low-speed communication area, and after concentrated transmission, the vehicle 102 repeats steps 328 and 330 while traveling on the remaining scheduled travel route. Furthermore, if there is a low-speed communication area on the scheduled travel route but buffering is not possible, the transmission and buffering of sensor data are not performed while the vehicle 102 travels in each low-speed communication area (see step 326), and after the vehicle 102 passes the last low-speed communication area, steps 328 and 330 are repeated while traveling on the remaining scheduled travel route.

[0071] As described above, when the scheduled driving route of the vehicle-mounted device 100 includes a low-speed communication area, the vehicle-mounted gateway 122 secures storage capacity for buffering in the memory 142, and buffers the sensor data while the vehicle 102 is traveling in the low-speed communication area (see step 318). Thereafter, when the vehicle 102 passes through the low-speed communication area (the result of the determination in step 316 is "No"), the vehicle-mounted gateway 122 collectively transmits the buffered sensor data (see step 320). Therefore, even if the vehicle 102 is traveling in an environment where the wireless communication speed is low, the vehicle-mounted device 100 can transmit the transmitted sensor data to the first server 104 without reducing the quality of the transmitted sensor data. Therefore, the first server 104 can maintain the service. In addition, by collectively transmitting the buffered sensor data, the vehicle-mounted device 100 can transmit the buffered sensor data to the first server 104 without wasting it.

[0072] In addition, when a destination is newly set and a planned driving route of the vehicle 102 is newly determined, the vehicle gateway 122 executes the Figure 8 The procedure shown.

[0073] (Actions of the first server) Reference Fig. 9 , the operation of the first server 104, that is, the function of receiving sensor data from the vehicle-mounted device 100 and providing services will be described. Fig. 9 The processing shown is done by Figure 4 This is realized by the control unit 150 of the first server 104 reading a predetermined program from the memory 152 and executing the program.

[0074] In step 400, the control unit 150 requests the transmission of sensor data to a plurality of vehicles (specifically, vehicle-mounted devices). Then, control moves to step 402. The transmission of the request can be performed, for example, by broadcasting. At this time, the control unit 150 transmits a transmission request including information on the required data quality and the allowable delay time as described above. In response to the request, the vehicle-mounted gateway 122 of the vehicle-mounted device 100 transmits the sensor data output from the vehicle-mounted sensor 124 mounted on the vehicle 102 to the first server 104 as described above, and when the planned driving route is determined, the execution Figure 8 The procedure shown.

[0075] In step 402 , the control unit 150 determines whether the sensor data has been received. If it is determined that the sensor data has been received, the control proceeds to step 404 . Otherwise, the control proceeds to step 406 .

[0076] In step 404 , the control unit 150 transfers the received sensor data to an application (ie, a program) of a corresponding service (eg, a remote monitoring service) executed by the first server 104 . Thereafter, control proceeds to step 406 .

[0077] In step 406, the control unit 150 determines whether an instruction to terminate is received. The instruction to terminate is given by, for example, operating an operation unit (not shown) of a keyboard or mouse provided in the first server 104. If it is determined to be terminated, control moves to step 408. Otherwise, control returns to step 402 and the above-mentioned process is repeated.

[0078] In step 408, the control unit 150 transmits a notification that the transmission of sensor data is not necessary to the vehicle that requested the transmission of sensor data in step 400. The transmission of the request can be performed by broadcasting, for example. Thereafter, this routine ends.

[0079] Through the above, the first server 104 can provide services using the sensor data uploaded from the vehicle-mounted device of the vehicle. In addition, when the vehicle-mounted device 100 uploads the sensor data to the first server 104, if the planned driving path of the vehicle 102 is calculated, the sensor data is buffered while the vehicle 102 is driving in the low-speed communication area, and if the vehicle 102 passes through the low-speed communication area, the buffered sensor data is sent in a concentrated manner. Therefore, even if the vehicle 102 is driving in an environment with a low wireless communication speed, the vehicle-mounted device 100 can send the sensor data to the first server 104 without reducing the quality of the sent sensor data. Therefore, the first server 104 can maintain the service.

[0080] (Actions of the second server) Reference Fig.10The operation of the second server 106, that is, the function of generating a communication performance map and transmitting the communication performance map in response to a request, will be described. Fig.10 The processing shown is done by Figure 5 This is realized by the control unit 160 of the second server 106 reading and executing a predetermined program from the memory 162 . The communication performance map is stored in the memory 162 .

[0081] In step 500, the control unit 160 determines whether a request for a communication performance map has been received. If it is determined that a request for a communication performance map has been received, the control moves to step 502. Otherwise, the control moves to step 504. For example, as described above, a request is made from the vehicle-mounted device 100 to send a communication performance map (see FIG. 1 ) to which information indicating a planned travel route is added. Figure 8 When receiving the request, the control unit 160 determines "yes".

[0082] In step 502 , the control unit 160 reads out the communication performance map of the corresponding area corresponding to the request from the memory 162 and transmits it. The transmission destination can be determined by the transmission source address (eg, IP address) of the request received in step 500 . Then, the control proceeds to step 508 .

[0083] If the result of determination in step 500 is "No", in step 504, the control unit 150 determines whether the communication performance data is received. If it is determined that it is received, the control moves to step 506. Otherwise, the control moves to step 508. The communication performance data is, for example, data indicating the actual state of wireless communication on each road (for example, communication speed and signal strength). For example, the vehicle-mounted device of each vehicle adds position information to the communication speed and signal strength when the vehicle-mounted device performs wireless communication with the outside in a time series, and stores it as communication performance data, and the stored communication performance data is periodically sent to the second server 106.

[0084] In step 506 , the control unit 160 stores the communication performance data received in step 504 in the memory 162 . At this time, the control unit 160 appropriately updates the existing communication performance map using the received new communication performance data. Thereafter, the control proceeds to step 508 .

[0085] In step 508, the control unit 160 determines whether an end instruction is received. The end instruction is given by operating the keyboard or mouse operation unit (not shown) of the second server 106, for example. If it is determined to be ended, this program ends. Otherwise, the control returns to step 500 and the above-mentioned process is repeated.

[0086] Through the above, the second server 106 can use the communication performance data uploaded from the vehicle-mounted device of each vehicle to generate and update the communication performance map, and receive the request to send the communication performance map. In addition, when the sensor data is uploaded to the first server 104, the vehicle-mounted device 100 can use the communication performance map received from the second server 106 to easily determine whether the planned driving path of the vehicle 102 includes a low-speed communication area. When calculating the planned driving path, the vehicle-mounted device 100 buffers the sensor data while the vehicle 102 is traveling in the low-speed communication area, and when the vehicle 102 passes through the low-speed communication area, the buffered sensor data is sent in a concentrated manner. Therefore, even if the vehicle 102 is traveling in an environment with a low wireless communication speed, the vehicle-mounted device 100 can send the sent sensor data to the first server 104 without reducing the quality of the sent sensor data.

[0087] In the above description, the case where the buffer capacity is calculated when the vehicle 102 has approached the low-speed communication area (i.e., the prescribed range) is described, but the present invention is not limited thereto. The buffer capacity may also be calculated when the scheduled driving route is calculated and the corresponding communication performance map is obtained. For example, if the scheduled driving route is relatively short, the vehicle 102 can travel for a relatively short time, and the change in the empty capacity of the memory 142 is relatively small. Therefore, the buffer capacity may be pre-calculated sufficiently in advance before the vehicle 102 approaches the low-speed communication area.

[0088] In the above description, the case where the vehicle-mounted device 100 obtains the wireless communication speed on the scheduled driving route based on the communication performance map received from the second server 106 is described, but the present invention is not limited to this. The vehicle-mounted device only needs to be able to obtain the wireless communication speed on the scheduled driving route of the vehicle 102 from the outside. For example, the vehicle 102 may also determine the wireless communication speed on the scheduled driving route of the vehicle 102 using a map related to the wireless communication speed provided by a wireless communication service company or the like (for example, a regional map of 5G and LTE (Long Term Evolution)).

[0089] In the above description, the case where the vehicle-mounted device 100 and the vehicle-mounted devices of the other vehicles 112 transmit the communication performance data to the second server 106 is described, but the present invention is not limited thereto. The vehicle-mounted device 100 may not store the communication performance data and may not transmit the communication performance data to the second server 106. In this case, the vehicle-mounted device 100 may not include the communication performance recording unit 208 and the communication performance transmitting unit 210.

[0090] In addition, each process (function) of the above-mentioned embodiment can also be implemented by a processing circuit (Circuitry) including one or more processors. In addition to the above-mentioned one or more processors, the above-mentioned processing circuit can also be composed of an integrated circuit that combines one or more memories, various analog circuits, and any one of various digital circuits. The above-mentioned one or more memories store programs (commands) that enable the above-mentioned one or more processors to perform the above-mentioned processes. The above-mentioned one or more processors can perform the above-mentioned processes according to the above-mentioned programs read from the above-mentioned one or more memories, or according to logic circuits designed to perform the above-mentioned processes in advance. The above-mentioned processor can be a CPU, GPU (Graphics Processing Unit: Graphics Processing Unit), DSP (Digital Signal Processor: Digital Signal Processor), FPGA (Field Programmable Gate Array: Field Programmable Gate Array) and ASIC (Application Specific Integrated Circuit: Application Specific Integrated Circuit) and other various processors suitable for computer control. In addition, the above-mentioned multiple processors that are physically separated can also cooperate with each other to perform the above-mentioned processes. For example, the processors installed in physically separate computers may cooperate with each other via a network such as a LAN (Local Area Network), a WAN (Wide Area Network), and the Internet to execute the above-mentioned processes.

[0091] In addition, it is possible to provide a computer recording a process for executing the in-vehicle device 100 (specifically, a process executed by the in-vehicle gateway 122 (for example, Figure 8 The recording medium is, for example, an optical disc (DVD (Digital Versatile Disc) etc.) or a removable semiconductor memory (USB (Universal Serial Bus) memory etc.). The computer program can be transmitted via a communication line, and the recording medium means a non-temporary recording medium. By making the computer read the program stored in the recording medium, the computer can maintain the cloud collaboration service even when the state of the external environment of the vehicle-mounted device deteriorates as described above, and can provide services from the server.

[0092] (Note) That is, a computer-readable non-transitory recording medium stores a computer program that enables a computer mounted on a vehicle to implement the following functions: a communication function for communicating with an external device and transmitting sensor data detected by a sensor mounted on the vehicle to the external device; and The buffer control function determines whether to perform buffering by storing the sensor data in a storage unit instead of transmitting the sensor data through the communication function, based on a wireless communication speed with the external device based on the communication function, and performs the buffering based on the determination result.

[0093] The present disclosure is described above by describing the embodiments, but the above embodiments are illustrative and the present disclosure is not limited to the above embodiments. The scope of the present disclosure is indicated by each claim based on the description of the detailed description of the invention, including all changes within the meaning and scope equivalent to the sentences recorded therein. Description of Reference Numerals

[0094] 100, 240 Vehicle-mounted devices 102 Vehicles 104 First Server 106 Second Server 108 Base Stations 110 Network 112 Other vehicles 114 Infrastructure Sensors 120, 154, 164 Ministry of Communications 122 Vehicle Gateway 124 Vehicle Sensors 126 Vehicle Status Management Department 128 Driving Control Unit 132, 156, 166 bus 140, 150, 160 Control Unit 142, 152, 162 Memory 200 Communication performance map information DB 202 Path Computation Department 204 CAN 206 Buffer Control Unit 208 Communication Performance Record Department 210, 232 Communication performance sending department 212, 234 Communications Performance Acquisition Department 214 Driving Department 230 Communication performance map information 220, 222 low-speed communication area Steps 300, 302, 304, 306, 308, 310, 312, 314, 316, 318, 320, 322, 324, 326, 328, 330, 400, 402, 404, 406, 408, 500, 502, 504, 506, 508 900 pedestrians A destination.

Claims

1. A vehicle-mounted device, mounted on a vehicle, The vehicle-mounted device comprises: a communication unit that communicates with an external device and transmits sensor data detected by a sensor mounted on the vehicle to the external device; and The buffer control unit determines whether to perform buffering by storing the sensor data in a storage unit without transmitting the sensor data through the communication unit based on a wireless communication speed between the communication unit and the external device, and performs the buffering based on the determination result.

2. The vehicle-mounted device according to claim 1, wherein: The buffering control unit determines to perform the buffering when a low-speed communication state in which the wireless communication speed is equal to or lower than a predetermined value occurs in a predetermined range on a planned travel route of the vehicle, and performs the buffering while the vehicle travels in the predetermined range.

3. The vehicle-mounted device according to claim 2, wherein: The communication unit further receives information indicating required data quality transmitted from the external device, The required data quality indicates the data capacity per unit time of the sensor data transmitted from the in-vehicle device to the external device. The buffer control unit calculates a predicted time for the vehicle to travel within the predetermined range, calculates a storage capacity required for the buffer using the predicted time and the required data quality, and determines whether the calculated storage capacity can be secured in the storage unit.

4. The vehicle-mounted device according to claim 3, wherein: The buffer control unit receives a message that the vehicle-mounted device has approached the predetermined range and is within a predetermined distance, calculates the predicted time, calculates the storage capacity, and determines whether the storage capacity can be secured in the storage unit.

5. The vehicle-mounted device according to claim 3 or 4, wherein: If the storage capacity cannot be ensured, the buffer control unit causes the communication unit to transmit information indicating that the sensor data cannot be transmitted to the external device.

6. The vehicle-mounted device according to any one of claims 3 to 5, wherein: The communication unit further receives information indicating an allowable delay time transmitted from the external device, If the predicted time is equal to or longer than the allowable delay time, the buffer control unit causes the communication unit to transmit information indicating that the sensor data cannot be transmitted to the external device.

7. The vehicle-mounted device according to any one of claims 1 to 6, wherein: The communication unit further receives a communication performance map from outside the vehicle-mounted device. Information indicating a road and information indicating an actual speed of wireless communication on the road are included in the communication performance map in a corresponding manner. The buffer control unit determines information indicating a road corresponding to the planned travel route from information indicating the road included in the communication performance map, and determines whether to perform the buffering using information indicating the actual speed corresponding to the determined information as information indicating the wireless communication speed.

8. The vehicle-mounted device according to any one of claims 1 to 7, wherein: After performing the buffering, if the buffering is not necessary, the buffer control unit causes the communication unit to transmit the sensor data stored in the storage unit through the buffering to the external device.

9. A control method, which is a control method of a vehicle-mounted device mounted on a vehicle, The control method comprises: a communication step of communicating with an external device and sending sensor data detected by a sensor mounted on the vehicle to the external device; and The buffer control step determines whether to perform buffering by storing the sensor data in a storage unit and not transmitting the sensor data through the communication step based on the wireless communication speed with the external device based on the communication step, and performs the buffering based on the determination result.

10. A computer program that enables a computer installed in a vehicle to implement the following functions: a communication function for communicating with an external device and transmitting sensor data detected by a sensor mounted on the vehicle to the external device; and The buffer control function determines whether to perform buffering by storing the sensor data in a storage unit and not transmitting the sensor data through the communication function, based on a wireless communication speed with the external device based on the communication function, and performs the buffering based on the determination result.

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