Vehicle system

Abstract

To provide a vehicle system in which local map data around the own vehicle can be acquired, transmission load can be reduced, the acquisition cycle of the local map data based on the position of the vehicle can be shortened, and the accuracy of vehicle control can be improved.SOLUTION: A vehicle system includes: transmitting the positional information of the own vehicle per position transmission period; transmitting a reference position and local map data that has a relative position of the peripheral area of the own vehicle position based on the reference position per map transmission period; converting the relative position based on the reference position per conversion period to a position in an own vehicle coordinate system based on the own vehicle position, on the basis of the latest positional information of the own vehicle; and calculating an amount of vehicle control of the own vehicle using the position in the own vehicle coordinate system. The conversion period is longer than the position transmission period and shorter than the map transmission period.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] This disclosure relates to vehicle systems. [Background technology]

[0002] Technologies related to driving support control that supports driving of a vehicle using map data have been proposed. Such driving support control includes, for example, automatic driving control that automatically drives a vehicle without the driver's involvement based on the driving environment around the vehicle and map data, and driving support control that supports driving by the driver.

[0003] For example, Patent Document 1 listed below discloses a system that uses map data and the vehicle's position to select lanes along which the vehicle is likely to travel in the future as target lanes, extracts only the map data for the target lanes, and supports the vehicle's travel based on the extracted map data.

[0004] Furthermore, Patent Document 2 discloses a system that changes the shape and size of the area extracted on the map based on the driving behavior of the vehicle, for local map data in which map data of an area close to the vehicle is extracted based on high-precision map data and the vehicle's position. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] JP 2021-192011 A [Patent Document 2] JP 2022-108069 A Summary of the Invention [Problem to be solved by the invention]

[0006] However, in Patent Documents 1 and 2, the amount of data is reduced by placing restrictions on the map information to be transmitted. In other words, the types of map information available for driving assistance are limited. In addition, when transmitting map data based on the position of the vehicle, the map data needs to be transmitted in accordance with the movement of the vehicle for vehicle control, so the transmission cycle needs to be shortened. However, there is a limit to how much the transmission cycle of map data, which has a large amount of data, can be shortened, and it is difficult to shorten the transmission delay relative to the movement of the vehicle.

[0007] Therefore, an object of the present disclosure is to provide a vehicle system that can reduce the load of acquiring and transmitting local map data around the vehicle while shortening the acquisition period of local map data based on the vehicle's position, thereby improving the accuracy of vehicle control. [Means for solving the problem]

[0008] The vehicle system according to the present disclosure includes: a position acquisition unit that acquires position information of the vehicle and transmits the position information of the vehicle at each position transmission period; a local map generating unit that generates local map data of a surrounding area of ​​the position of the vehicle based on the position information of the vehicle and map data received from the position acquiring unit, calculates a relative position based on a reference position as position information included in the local map data, and transmits the local map data and the reference position at each map transmission period; a coordinate conversion unit that converts, for each conversion period, a relative position based on the reference position included in the local map data received from the local map generation unit, into a position in a host vehicle coordinate system based on the position of the host vehicle; and a vehicle control unit that calculates a vehicle control amount for controlling traveling of the host vehicle by using a position of the host vehicle coordinate system of the local map data, The conversion period is longer than the position transmission period and shorter than the map transmission period. Effect of the Invention

[0009] According to the vehicle system of the present disclosure, the local map data has a large amount of data, and the original position information is time-invariant data, so the map transmission period is set relatively long. On the other hand, the position information of the vehicle has a small amount of data, is time-variant data due to the movement of the vehicle, and the latest information is required for vehicle control, so the position transmission period is set relatively short. The coordinate conversion requires a relatively large amount of data to be converted, but the latest information according to the movement of the vehicle is required for vehicle control, so the conversion period is set to match the calculation period of the vehicle control amount. Therefore, by making the conversion period longer than the position transmission period and shorter than the map transmission period, the map transmission period of the local map data, which is time-invariant and has a large amount of data, is made the longest to reduce the processing load and communication load, while the position transmission period of the position information of the vehicle is made the shortest, and the coordinate conversion for calculating the vehicle control amount is performed using the latest position information of the vehicle, thereby improving the accuracy of vehicle control. In addition, the position of the map data is latitude and longitude, and is a position that represents the position of the entire earth, so the number of digits is large and the amount of data is large. On the other hand, since the relative position of the local map data based on the reference position is local differential position data, the number of digits is small, and the amount of data to be transmitted can be reduced. This makes it possible to shorten the map transmission period and reduce the processing load and communication load. Therefore, while reducing the load of acquiring and transmitting local map data around the vehicle, it is possible to shorten the acquisition period of local map data in the vehicle coordinate system based on the vehicle position, thereby improving the accuracy of vehicle control. [Brief description of the drawings]

[0010] [Figure 1] 1 is a schematic block diagram of a vehicle system according to a first embodiment. [Diagram 2] 1 is a schematic hardware configuration diagram of a map transmission device according to a first embodiment. [Diagram 3] 1 is a schematic hardware configuration diagram of a vehicle control device according to a first embodiment. [Figure 4] FIG. 2 is a diagram for explaining coordinate transformation according to the first embodiment. [Diagram 5]4 is a time chart for explaining each period and processing of each period according to the first embodiment. [Figure 6] 6 is a diagram showing an example of each position and a coordinate system at times t5 and t6 in FIG. 5 according to the first embodiment. FIG. [Figure 7] 6 is a diagram showing an example of each position and a coordinate system at times t7, t8, and t9 in FIG. 5 according to the first embodiment. FIG. [Figure 8] FIG. 11 is a diagram for explaining division and transmission of map data by type according to the second embodiment. [Figure 9] FIG. 13 is a diagram for explaining transmission of local map data of a differential region according to the third embodiment. [Figure 10] FIG. 13 is a diagram for explaining transmission of a plurality of local map data using the same reference position according to the fourth embodiment. [Figure 11] FIG. 13 is a diagram for explaining a change in the range of the surrounding area depending on the type of map data in the fifth embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0011] 1. First embodiment A vehicle system 1 according to the first embodiment will be described with reference to the drawings. In the present embodiment, the vehicle system 1 is mounted on a host vehicle.

[0012] As shown in FIG. 1, the vehicle system 1 includes a position detection device 31, a vehicle state detection device 32, a map database 33, a map transmission device 34, a vehicle control device 35, a drive control device 36, a power machine 8, an electric steering device 7, and an electric braking device 9.

[0013] The position detection device 31 detects the current position (latitude, longitude, altitude) of the vehicle. As the position detection device 31, a GNSS antenna or the like that receives signals output from an artificial satellite such as a GNSS (Global Navigation Satellite System) is used.

[0014] The vehicle state detection device 32 is a detection device that detects the state of the host vehicle, which is the driving state and running state of the host vehicle. In this embodiment, the vehicle state detection device 32 detects the direction of the host vehicle, the speed, acceleration, yaw rate, steering angle, lateral acceleration, etc. of the host vehicle as the running state of the host vehicle. For example, the vehicle state detection device 32 is provided with a direction sensor, a speed sensor that detects the rotational speed of the wheels, an acceleration sensor, an angular velocity sensor, a steering angle sensor, etc.

[0015] The driving state of the vehicle is detected by detecting the acceleration / deceleration operation, steering angle operation, and lane change operation by the driver. For example, an accelerator position sensor, a brake position sensor, a steering angle sensor (handle angle sensor), a steering torque sensor, a turn signal position switch, and the like are provided as the vehicle state detection device 32.

[0016] The map database 33 stores the positions of each part of the road and features around the road. For example, the positions of each part of the dividing line, the positions of each part of the road edge, and the positions of each sign are stored. The positions are latitude, longitude, altitude, etc. The road edges include road shoulders, roadside walls, building walls, fences, guardrails, structures in the median strip, lane dividers (rubber poles, etc.), delineators, utility poles, roadside trees, etc. The signs include traffic lights, road signs, etc. The map database 33 also stores various information such as road information (number of lanes, road type, speed limit, etc.). The map database 33 is mainly composed of a storage device. The map database 33 may be provided in a server outside the vehicle connected to a network, and the map transmission device 34 may obtain information from the server outside the vehicle via a wireless communication device.

[0017] The drive control device 36 includes a power control device, a brake control device, an automatic steering control device, a light control device, etc. The power control device controls the output of a power machine 8 such as an internal combustion engine or a motor. The brake control device controls the braking operation of an electric brake device 9. The automatic steering control device controls the electric steering device 7. The light control device controls a direction indicator, a hazard lamp, etc.

[0018] 1-1. Map transmission device 34 and vehicle control device 35 The map transmission device 34 includes functional units such as a position acquisition unit 341 and a local map generation unit 342. The vehicle control device 35 includes functional units such as a coordinate conversion unit 351 and a vehicle control unit 352. The functions of the map transmission device 34 and the vehicle control device 35 are realized by processing circuits included in each device. Specifically, as shown in Figs. 2 and 3, each of the map transmission device 34 and the vehicle control device 35 includes an arithmetic processing device 90 such as a central processing unit (CPU), a storage device 91, an input / output device 92 that inputs and outputs external signals to the arithmetic processing device 90, and the like. The map transmission device 34 and the vehicle control device 35 communicate with each other to transmit and receive information. For example, communication standards such as CAN (Controller Area Network), Ethernet, and Flexray (all of which are registered trademarks) are used for communication.

[0019] The arithmetic processing device 90 may be an ASIC (Application Specific Integrated Circuit), an IC (Integrated Circuit), a DSP (Digital Signal Processor), an FPGA (Field Programmable Gate Array), a GPU (Graphics Processing Unit), an AI (Artificial Intelligence) chip, various logic circuits, various signal processing circuits, etc. Also, the arithmetic processing device 90 may be a plurality of the same or different types, and each process may be shared and executed. As the storage device 91, various storage devices such as a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory, an EEPROM (Electrically Erasable Programmable Read Only Memory), a hard disk, etc. are used.

[0020] The input / output device 92 includes a communication device, an A / D converter, an input / output port, a drive circuit, etc. The input / output device 92 of the map transmission device 34 is connected to the position detection device 31, the vehicle state detection device 32, the map database 33, the vehicle control device 35, etc., and communicates with these devices. The input / output device 92 of the vehicle control device 35 is connected to the vehicle state detection device 32, the drive control device 36, the map transmission device 34, etc., and communicates with these devices.

[0021] The functions of the functional units 341 and 342 or 351 and 352, etc., provided in the map transmission device 34 and the vehicle control device 35, respectively, are realized by the arithmetic processing device 90 executing software (programs) stored in the storage device 91 and cooperating with other hardware of the map transmission device 34, such as the storage device 91 and the input / output device 92. Various setting data used by the functional units 341 and 342 or 351 and 352, etc., are stored in the storage device 91, such as an EEPROM.

[0022] The position acquisition unit 341 and the local map generation unit 342 may be provided in separate processing devices and configured to communicate with the other processing devices.

[0023] 1-1-1. Position acquisition unit 341 The position acquisition unit 341 acquires the position information of the vehicle and transmits the position information of the vehicle at each position transmission period Tloc. The position information of the vehicle includes the latitude lat ego , longitude lon ego , and the orientation θ ego The position acquisition unit 341 acquires the position coordinates (latitude, longitude, altitude) of the vehicle from the detection information of the GNSS antenna at each position transmission period Tloc. The position acquisition unit 341 also acquires the direction θ of the vehicle from the detection information of the direction sensor. ego The vehicle's heading θ egois the angle of the longitudinal direction x of the vehicle based on north (north-south direction). The position acquisition unit 341 estimates the position information of the vehicle by hybrid navigation using the acceleration, angular velocity, and the like acquired from the vehicle state detection device 32 in addition to the detection information of the GNSS antenna and the direction sensor.

[0024] The position acquisition unit 341 transmits the acquired or estimated position information of the vehicle to the local map generation unit 342, the coordinate conversion unit 351, and the like, at each position transmission period Tloc.

[0025] 1-1-2. Local map generation unit 342 The local map generating unit 342 generates local map data of the surrounding area of ​​the vehicle's position based on the vehicle's position information and map data received from the position acquiring unit 341, calculates a relative position based on a reference position as the position information included in the local map data, and transmits the local map data and the reference position at each map transmission period Tmap. The reference position includes latitude and longitude, and may also include altitude. The relative position includes relative latitude and relative longitude based on the reference position (latitude and longitude), and may also include relative altitude.

[0026] The local map generating unit 342 sets a surrounding area including the latest vehicle position based on the latest vehicle position for each map transmission period Tmap. The surrounding area is set to a position range (latitude and longitude range) based on the latest vehicle position. The shape of the position range may be any shape such as a rectangle, a circle, an ellipse, or a shape along a road. The local map generating unit 342 acquires map data of the surrounding area of ​​the vehicle position from the map database 33. The local map generating unit 342 also sets a reference position based on the vehicle position. The reference position is set to a position close to the vehicle position, for example, to the vehicle position.

[0027] The local map generating unit 342 converts the position of each part included in the map data of the surrounding area of ​​the vehicle into a relative position based on a reference position at each map transmission period Tmap to generate local map data. As shown in the following formula, the local map generating unit 342 converts the position of each part (latitude lat map and longitude lon map ) to the reference position (latitude lat ref and longitude lon ref ) to determine the relative position of each part (relative latitude Rlat map and relative longitude Rlon map That is, the relative position is the relative latitude and the relative longitude with the reference position as the origin.

number

[0028] For example, the positions of each part of the lane markings, each part of the road edges, and each sign included in the map data of the area surrounding the vehicle are converted into relative positions based on a reference position.

[0029] The position of the map data is expressed as latitude and longitude, and represents the position of the whole earth, so the number of digits is large and the amount of data is large. On the other hand, the relative position of the local map data based on the reference position is local differential position data, so the number of digits is small and the amount of data to be transmitted can be reduced.

[0030] The local map generating unit 342 transmits the generated local map data and the reference position to the coordinate conversion unit 351 and the like at each map transmission period Tmap.

[0031] 1-1-3. Coordinate conversion unit 351 The coordinate conversion unit 351 converts, at each conversion period Tcnv based on the latest position of the vehicle received from the position acquisition unit 341, a relative position based on a reference position included in the local map data received from the local map generation unit 342 into a position in the vehicle coordinate system based on the position of the vehicle.

[0032] As shown in FIG. 4 and the following formula, the relative position (relative latitude Rlat map and relative longitude Rlon map ) to the vehicle's latest location information (latitude lat ego , longitude lon ego , and the orientation θ ego , and the reference position (longitude lat ref , longitude lon ref ), a rotation coordinate transformation and a translation transformation are performed to obtain the position of the vehicle coordinate system (vertical position x map , horizontal position y map )

number

[0033] Here, the position of the vehicle coordinate system is the longitudinal position of the vehicle based on the vehicle (longitudinal position x map ) and the lateral position of the vehicle (lateral position y map The origin of the host vehicle coordinate system is set to the position of the host vehicle.

[0034] 1-1-4. Vehicle control unit 352 The vehicle control unit 352 calculates a vehicle control amount for controlling the traveling of the vehicle by using the position of the vehicle coordinate system of the local map data, and transmits the vehicle control amount to the drive control device 36. The drive control device 36 controls the traveling of the vehicle. The vehicle control unit 352 calculates the vehicle control amount for each vehicle control period Tvc. For example, the vehicle control period Tvc is set to be the same as the conversion period Tcnv, and the calculation processing of the vehicle control amount is preferably performed after the conversion processing of the coordinate conversion unit 351.

[0035] For example, the vehicle control unit 352 assists the driver in driving or performs automatic driving based on the positions of the vehicle's coordinate system, such as lane markings and signs included in the local map data. For example, the vehicle control unit 352 determines the lane in which the vehicle is traveling, calculates a target steering angle for traveling along the lane or a target steering angle for changing lanes to an adjacent lane, and transmits the target steering angle to the drive control unit 36 ​​(automatic steering control unit). The vehicle control unit 352 may also determine a target speed, a turn signal operation command, and the like, and transmit them to the drive control unit 36 ​​(power control unit, brake control unit, light control unit, and the like).

[0036] The power control device controls the output of a power machine 8 such as an internal combustion engine or a motor so that the speed of the vehicle follows a target speed. The brake control device controls the braking operation of an electric brake device 9 so that the speed of the vehicle follows a target speed. The automatic steering control device controls the electric steering device 7 so that the steering angle follows a target steering angle. The light control device controls a turn signal according to an operation command for the turn signal.

[0037] In addition, the vehicle control unit 352 may detect other vehicles and obstacles around the vehicle using information detected by surrounding monitoring devices such as cameras and radars, and use the information for driving assistance or automatic driving. For example, lane keeping control, obstacle avoidance control, lane change control, cruise control, vehicle distance control, leading vehicle following control, etc. are performed as vehicle control.

[0038] The vehicle control unit 352 may provide various types of guidance (for example, route guidance, surrounding information guidance, and risk guidance) to the driver via a display device or speaker based on various types of position information included in the local map data.

[0039] 1-1-5. Setting each cycle The conversion period Tcnv is longer than the position transmission period Tloc and shorter than the map transmission period Tmap.

[0040] The local map data has a large amount of data, and the original position information is time-invariant data, so the map transmission period Tmap is set relatively long. On the other hand, the position information of the vehicle has a small amount of data, and is time-variant data due to the movement of the vehicle, and the latest information is required for vehicle control, so the position transmission period Tloc is set relatively short. The coordinate conversion requires a relatively large amount of data to be converted, but the latest information according to the movement of the vehicle is required for vehicle control, so the conversion period Tcnv is set to match the calculation period of the vehicle control amount. Therefore, by making the conversion period Tcnv longer than the position transmission period Tloc and shorter than the map transmission period Tmap, the map transmission period Tmap of the local map data, which is time-invariant and has a large amount of data, is made the longest to reduce the processing load and communication load, while the position transmission period Tloc of the position information of the vehicle is made the shortest to perform coordinate conversion for calculating the vehicle control amount using the latest position information of the vehicle, thereby improving the accuracy of vehicle control.

[0041] In addition, the position of the map data is expressed as latitude and longitude, and represents the position of the entire earth, so the number of digits is large and the amount of data is large. On the other hand, the relative position of the local map data based on the reference position is local differential position data, so the number of digits is small and the amount of data to be transmitted can be reduced. Therefore, the map transmission period Tmap can be shortened and the processing load and communication load can be reduced.

[0042] Fig. 5 shows a time chart for explaining each period and the processing of each period. Fig. 6 shows an example of each position and coordinate system at times t5 and t6 in Fig. 5. Fig. 7 shows an example of each position and coordinate system at times t7, t8, and t9 in Fig. 5.

[0043] The position transmission period Tloc is set to the shortest, and the map transmission period Tmap is set to the longest, and the conversion period Tcnv is set to be longer than the position transmission period Tloc and shorter than the map transmission period Tmap in accordance with the vehicle control period Tvc.

[0044] The position transmission period Tloc is the shortest, and the latest vehicle position information is always used in the conversion process. On the other hand, the map transmission period Tmap is longer than the position transmission period Tloc and the conversion period Tcnv, and the same local map data used in the previous conversion process may be used in the current conversion process, but since the original position information of the map data is time-invariant, this is not a problem and the processing load and communication load can be reduced. Note that the map transmission period Tmap is set shorter than the period until the vehicle position deviates from the range of the previously transmitted local map data.

[0045] The conversion period Tcnv is set to be the same as the vehicle control period Tvc, and the conversion process is performed by the coordinate conversion unit 351 immediately before the calculation process of the vehicle control amount. Therefore, the vehicle control amount is calculated using the position information of the host vehicle coordinate system that has been coordinate-converted using the latest host vehicle position information, so that the accuracy of vehicle control can be improved.

[0046] 6, the same local map data, map 2, is used in the coordinate transformation at time t5 and time t6, but this is not a problem since the data is time-invariant. The coordinate transformation at time t5 uses position 11, which is the latest position of the host vehicle, and the coordinate transformation at time t6 uses position 13, which is the latest position of the host vehicle. Therefore, the accuracy of vehicle control can be improved by performing coordinate transformation using the latest position information of the host vehicle.

[0047] As shown in FIG. 7, in the coordinate transformation at times t7, t8, and t9, new local map data, map 3, is acquired and used for the coordinate transformation. The reference position of map 3 is moved in accordance with the movement of the host vehicle, and map data around the host vehicle can be used. The same local map data, map 3, is used in the coordinate transformation at times t7, t8, and t9, but the surrounding area from which the map data is acquired is appropriately set in accordance with the movement of the host vehicle, and since the data is time-invariant, there is no problem. The coordinate transformation at time t7 uses position 16, which is the latest position of the host vehicle, the coordinate transformation at time t8 uses position 18, which is the latest position of the host vehicle, and the coordinate transformation at time t9 uses position 21, which is the latest position of the host vehicle. Therefore, the coordinate transformation is performed using the latest position information of the host vehicle, and the accuracy of vehicle control can be improved.

[0048] 2. Second embodiment Next, a vehicle system 1 according to a second embodiment will be described. Descriptions of components similar to those of the first embodiment will be omitted. The basic configuration of the vehicle system 1 according to the second embodiment is similar to that of the first embodiment, but the method of generating and transmitting local map data by the local map generating unit 342 is different from that of the first embodiment.

[0049] In this embodiment, the local map generating unit 342 divides the local map data and the reference position and transmits them for each map transmission period Tmap.

[0050] According to this configuration, instead of transmitting all of the local map data in one map transmission period Tmap, the local map data is divided and transmitted in multiple map transmission periods Tmap, thereby reducing the processing and communication per map transmission period Tmap and reducing the processing load and communication load.

[0051] In this embodiment, the local map generating unit 342 divides the local map data and the reference position for each type of map data, and transmits them at each map transmission period Tmap.

[0052] For example, as shown in Fig. 8, lane markings, road edges, and signs are used as types of map data. The local map generating unit 342 generates and transmits local map data of lane marks, local map data of road edges, and local map data of signs in that order for each map transmission period Tmap.

[0053] For example, at time t1, the local map generation unit 342 sets a reference position O1 and the surrounding area of ​​the host vehicle based on the latest position information of the host vehicle acquired at time t1, converts the positions of each part of the lane lines included in the surrounding area map data of the host vehicle into relative positions based on the reference position O1, generates local map data of the lane lines, and transmits the local map data of the lane lines and the reference position O1. At time t2, the local map generation unit 342 sets a reference position O2 and the surrounding area of ​​the host vehicle based on the latest position information of the host vehicle acquired at time t2, converts the positions of each part of the road edge included in the surrounding area map data of the host vehicle into relative positions based on the reference position O2, generates local map data of the road edges, and transmits the local map data of the road edges and the reference position O2. At time t3, the local map generation unit 342 sets a reference position O3 and the surrounding area of ​​the host vehicle based on the latest position information of the host vehicle acquired at time t3, converts the positions of each part of the road edge included in the surrounding area map data of the host vehicle into relative positions based on the reference position O3, generates local map data of the road edge, and transmits the local map data of the road edge and the reference position O3.

[0054] The coordinate conversion unit 351 converts the relative positions of the multiple local map data received by dividing from the local map generation unit 342 into positions in the vehicle coordinate system based on the vehicle position at each conversion period Tcnv, based on the latest vehicle position received from the position acquisition unit 341. In this embodiment, the coordinate conversion unit 351 converts the relative positions of all map data types of local map data into positions in the vehicle coordinate system based on the latest vehicle position and the reference positions of each local map data at the same conversion period Tcnv. For example, the coordinate conversion unit 351 converts the relative position of the latest lane line local map data into a position in the vehicle coordinate system based on the latest vehicle position and the reference position of the latest lane line local map data at the same conversion period Tcnv, converts the relative position of the latest road edge local map data into a position in the vehicle coordinate system based on the latest vehicle position and the reference position of the latest road edge local map data, and converts the relative position of the latest sign local map data into a position in the vehicle coordinate system based on the latest vehicle position and the reference position of the latest sign local map data.

[0055] 3. Third embodiment Next, a vehicle system 1 according to a third embodiment will be described. Descriptions of components similar to those of the first or second embodiment will be omitted. The basic configuration of the vehicle system 1 according to the present embodiment is similar to that of the first or second embodiment, but the method of generating and transmitting local map data by the local map generation unit 342 is different from that of the first or second embodiment.

[0056] 9, in the present embodiment, the local map generation unit 342 transmits, in the current map transmission period Tmap, local map data of a difference region that is not included in the region of the local map data transmitted in the past map transmission period Tmap, and a reference position, within the region surrounding the position of the vehicle itself. The coordinate conversion unit 351 converts the relative position based on the reference position included in the local map data transmitted in the latest map transmission period Tmap and the relative position based on the reference position included in the local map data transmitted in the past map transmission period Tmap, into a position in the vehicle coordinate system.

[0057] According to this configuration, local map data of the difference area between the previous transmission area and the surrounding area of ​​the current vehicle position is transmitted, thereby reducing the transmission of duplicated data, shortening the map transmission period Tmap, and reducing the processing load and communication load.

[0058] The local map data and the reference position transmitted in the past are stored in a storage device such as a RAM. Note that the unnecessary local map data and the reference position in the past are sequentially deleted from the storage device.

[0059] The coordinate conversion unit 351 extracts, at the same conversion period Tcnv, local map data of the surrounding area corresponding to the latest position of the host vehicle and a reference position from the local map data and reference position transmitted in the past, and converts the extracted past local map data into a position in the host vehicle coordinate system based on the latest position of the host vehicle and the reference position of the past local map data, and also converts the local map data of the latest difference area into a position in the host vehicle coordinate system based on the latest position of the host vehicle and the reference position of the local map data of the latest difference area.

[0060] As in the second embodiment, the local map generating unit 342 may transmit local map data of a differential region and a reference position for each type of map data.

[0061] 4. Fourth embodiment Next, a vehicle system 1 according to a fourth embodiment will be described. Descriptions of components similar to those of the first embodiment will be omitted. The basic configuration of the vehicle system 1 according to this embodiment is similar to that of the first embodiment, but the method of generating and transmitting local map data by the local map generation unit 342 is different from that of the first embodiment.

[0062] In this embodiment, the local map generation unit 342 sets the same reference position among the multiple local map data and the reference position that are divided and transmitted in multiple map transmission periods Tmap. The coordinate conversion unit 351 converts the relative positions of the latest multiple local map data in which the same reference position is set, into positions in the host vehicle coordinate system based on the latest host vehicle position and the same reference position.

[0063] According to this configuration, in the coordinate conversion by the coordinate conversion unit 351, the conversion can be performed for the divided local map data using the same coordinate conversion formula in which the same reference position is set, thereby reducing the calculation processing load. Specifically, the calculation value of the movement conversion in the second term on the right side of the formula (2) becomes the same, thereby reducing the calculation processing load.

[0064] As in the second embodiment, the local map generation unit 342 divides the local map data and the reference position for each type of map data and transmits them at each map transmission period Tmap. For example, lane markings, road edges, and signs are used as types of map data.

[0065] 10, the same reference position O1 is used for the local map data of the lane lines, the local map data of the road edges, and the local map data of the signs, which are transmitted in a divided manner over three map transmission periods Tmap. Then, in the next three map transmission periods Tmap, a new same reference position is set, and the local map data of the lane lines, the road edges, and the signs is transmitted. The coordinate conversion unit 351 converts the relative positions of the latest local map data of the lane lines, the road edges, and the signs, for which the same reference position is set, into positions in the host vehicle coordinate system, based on the latest host vehicle position and the same reference position.

[0066] Alternatively, in the third embodiment, the local map generation unit 342 may set the same reference position between the local map data of the multiple differential regions and the reference position transmitted in the current and past map transmission periods Tmap. For example, the local map generation unit 342 changes the reference position every predetermined number of map transmission periods Tmap. The coordinate conversion unit 351 converts the relative positions of the local map data of the multiple differential regions in which the same reference position is set, into positions in the host vehicle coordinate system, based on the latest host vehicle position and the same reference position.

[0067] According to this configuration, the coordinate conversion unit 351 can convert the local map data of a plurality of differential regions using the same coordinate conversion formula in which the same reference position is set, thereby reducing the computational load. Specifically, the computational value of the movement conversion in the second term on the right side of the formula (2) becomes the same, thereby reducing the computational load.

[0068] 5. Fifth embodiment Next, a vehicle system 1 according to a fifth embodiment will be described. Descriptions of components similar to those of the first embodiment will be omitted. The basic configuration of the vehicle system 1 according to this embodiment is similar to that of the first embodiment, but the method of generating and transmitting local map data by the local map generation unit 342 is different from that of the first embodiment.

[0069] The local map generation unit 342 changes each type of data included in the local map data or the range of the surrounding area for generating local map data, depending on at least one of the type of map data included in the local map data, the speed of the host vehicle, and the type of road.

[0070] According to this configuration, the range of the surrounding area can be appropriately changed depending on at least one of the type of map data, the speed of the host vehicle, and the type of road, thereby optimizing the processing load and communication load.

[0071] For example, when lane lines, road edges, and signs are used as map data types, the range of the surrounding area for each map data type may be changed according to the lane lines, road edges, and signs. As shown in Fig. 11, lane lines and road edges have a large amount of data, so the range of the surrounding area is set narrow, while signs have a small amount of data, so the range of the surrounding area is set wide. The local map generation unit 342 transmits the local map data in which the surrounding area has been changed for each map data type at each map transmission period Tmap.

[0072] In addition, the range of the surrounding area is expanded as the speed of the vehicle increases. As the speed of the vehicle increases, the travel distance of the vehicle during the map transmission period Tmap increases, and the range of the required surrounding area increases. Thus, an appropriate range of the surrounding area can be set.

[0073] Furthermore, the required range of the surrounding area varies depending on the type of road, such as an expressway or a general road, and an appropriate range of the surrounding area can be set.

[0074] The range of the surrounding area may be changed by combining the type of map data, the speed of the vehicle, and the type of road. For example, the range of the surrounding area for each type of map data may be changed according to the speed of the vehicle.

[0075] 6. Sixth embodiment Next, a vehicle system 1 according to a sixth embodiment will be described. A description of components similar to those of the first embodiment will be omitted. The basic configuration of the vehicle system 1 according to the sixth embodiment is similar to that of the first embodiment, but the method of generating and transmitting local map data by the local map generating unit 342 is different from that of the first embodiment.

[0076] The local map generation unit 342 changes the map transmission period Tmap of each type of map data included in the local map data, or the map transmission period Tmap of the local map data, depending on at least one of the type of map data included in the local map data, the speed of the host vehicle, and the type of road.

[0077] According to this configuration, the map transmission period Tmap of each type of map data or the map transmission period Tmap of the local map data can be appropriately changed depending on at least one of the type of map data, the speed of the vehicle, and the type of road, thereby optimizing the processing load and communication load.

[0078] For example, when lane lines, road edges, and signs are used as types of map data, the map transmission period Tmap of the local map data of lane lines, the map transmission period Tmap of the local map data of road edges, and the map transmission period Tmap of the local map data of signs are changed. For example, the map transmission period Tmap of lane lines and road edges, which require frequent updates for driving control of the vehicle, is set to be short, and the map transmission period Tmap of signs, which do not require frequent updates, is set to be long.

[0079] In addition, the map transmission period Tmap of the local map data is set shorter as the speed of the host vehicle increases. As the speed of the host vehicle increases, the travel distance of the host vehicle per unit time increases, and more frequent transmission is required. Therefore, an appropriate map transmission period Tmap can be set.

[0080] Furthermore, the required map transmission period Tmap changes depending on the type of road, such as an expressway or a general road, and an appropriate map transmission period Tmap can be set.

[0081] The map transmission period Tmap may be changed in accordance with a combination of the type of map data, the speed of the vehicle, and the type of road. For example, the map transmission period Tmap for each type of map data may be changed according to the speed of the vehicle.

[0082] 7. Seventh embodiment Next, a vehicle system 1 according to a seventh embodiment will be described. Description of components similar to those of the above-described first embodiment will be omitted. The basic configuration of the vehicle system 1 according to the present embodiment is similar to that of the first embodiment, but the process of the coordinate conversion unit 351 is different from that of the first embodiment.

[0083] The coordinate conversion unit 351 changes the conversion period Tcnv for each type of map data included in the local map data, depending on the type of map data included in the local map data.

[0084] According to this configuration, the conversion period Tcnv for each type of map data can be appropriately changed depending on the type of map data, thereby optimizing the processing load.

[0085] For example, when lane markings, road edges, and signs are used as types of map data, the conversion period Tcnv of the map data of lane marks, the conversion period Tcnv of the map data of road edges, and the conversion period Tcnv of the map data of signs are changed. For example, the conversion period Tcnv of the map data of lane marks and road edges, which require frequent updates for driving control of the vehicle, is set to be short, and the conversion period Tcnv of the map data of signs, which do not require frequent updates, is set to be long. For example, the map data of lane marks and road edges is converted at the same conversion period Tcnv as the vehicle control period Tvc, and the map data of signs is converted at a predetermined number of conversion periods Tcnv.

[0086] In the present disclosure, various exemplary embodiments and examples are described, but various features, aspects, and functions described in one or more embodiments are not limited to the application of a specific embodiment, and can be applied to the embodiments alone or in various combinations. Therefore, countless modifications not illustrated are expected within the scope of the technology disclosed in the present specification. For example, the modification, addition, or omission of at least one component, and the extraction and combination of at least one component with components of other embodiments are included. [Explanation of symbols]

[0087] 1: vehicle system, 341: position acquisition unit, 342: local map generation unit, 351: coordinate conversion unit, 352: vehicle control unit, Tcnv: conversion cycle, Tloc: position transmission cycle, Tmap: map transmission cycle, Tvc: vehicle control cycle

Claims

1. a position acquisition unit that acquires position information of the vehicle and transmits the position information of the vehicle at each position transmission period; a local map generating unit that generates local map data of a surrounding area of ​​the position of the vehicle based on the position information of the vehicle and map data received from the position acquiring unit, calculates a relative position based on a reference position as position information included in the local map data, and transmits the local map data and the reference position at each map transmission period; a coordinate conversion unit that converts, for each conversion period, a relative position based on the reference position included in the local map data received from the local map generation unit, into a position in a host vehicle coordinate system based on the position of the host vehicle; and a vehicle control unit that calculates a vehicle control amount for controlling traveling of the host vehicle by using a position of the host vehicle coordinate system of the local map data, A vehicle system, wherein the conversion period is longer than the position transmission period and shorter than the map transmission period.

2. The vehicle system according to claim 1 , wherein the local map generating unit divides the local map data and the reference position and transmits the divided data for each map transmission period.

3. the local map generation unit transmits, in the current map transmission cycle, the local map data and the reference position for a difference region that is not included in a region of the local map data transmitted in the previous map transmission cycle, within a peripheral region of the position of the vehicle; 3. The vehicle system according to claim 1, wherein the coordinate conversion unit converts a relative position based on the reference position included in the local map data transmitted in the latest map transmission period and a relative position based on the reference position included in the local map data transmitted in the past map transmission period into a position in the host vehicle coordinate system.

4. The vehicle system according to claim 2 , wherein the local map generating unit sets the same reference position among the plurality of local map data and the reference position that are divided and transmitted in the plurality of map transmission periods.

5. The vehicle system according to claim 3 , wherein the local map generating unit sets the same reference position among the local map data of the plurality of differential regions and the reference position transmitted in the current and past map transmission periods.

6. The vehicle system according to claim 1 , wherein the local map generation unit changes each type of data included in the local map data or the range of the surrounding area for which the local map data is generated.

7. 2. The vehicle system according to claim 1, wherein the local map generation unit changes each type of data included in the local map data or the range of the surrounding area for which the local map data is generated, depending on at least one of a type of map data included in the local map data, a speed of the host vehicle, and a type of road.

8. The vehicle system according to claim 1 , wherein the local map generation unit changes the map transmission period for each type of map data included in the local map data, or changes the map transmission period for the local map data.

9. 7. The vehicle system according to claim 1, wherein the local map generation unit changes the map transmission period for each type of map data included in the local map data or the map transmission period for the local map data, depending on at least one of a type of map data included in the local map data, a speed of the vehicle, and a type of road.

10. The vehicle system according to claim 1 , wherein the coordinate conversion unit changes the conversion period for each type of map data included in the local map data.

11. The vehicle system according to claim 1 , wherein the coordinate conversion unit changes the conversion period for each type of map data included in the local map data in accordance with the type of map data included in the local map data.

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