Control system

Abstract

A control system configured to control a vehicle configured to travel by being driven without a driver, includes an acquisition unit configured to acquire precondition information related to a road surface on which the vehicle travels and a friction force between the vehicle and the road surface, and a control unit configured to determine an acceleration at which the vehicle travels on the road surface using the precondition information, and cause the vehicle to travel at the determined acceleration.

Description

Technical Field

[0001] This invention relates to a control system. Background Technology

[0002] To date, a technology for enabling vehicles to operate autonomously in vehicle manufacturing plants is known (Japanese Unexamined Patent Application Publication No. 2017-538619 (JP 2017-538619 A)). Summary of the Invention

[0003] A road surface wet with a liquid such as water may have less friction between the road surface and the wheels than a dry road surface. As friction decreases, the wheels are more likely to slip on the surface. Therefore, when the vehicle's deceleration is the same regardless of the presence or absence of moisture and the degree of wetness, the braking distance increases with increasing wetness. Consequently, the vehicle may not be able to stop at the desired position. When the vehicle's acceleration is the same regardless of the presence or absence of moisture and the degree of wetness, the vehicle may be more likely to sway and become unstable in posture with increasing wetness. This problem can also occur when the friction between the road surface and the wheels varies due to factors other than road surface wetness, such as differences in road material or vehicle type.

[0004] This disclosure may be implemented in the following forms.

[0005] (1) According to one aspect of this disclosure, a control system is provided. The control system, configured to control a vehicle configured to operate autonomously, includes: an acquisition unit configured to acquire precondition information related to the friction between the road surface on which the vehicle travels and the wheels of the vehicle; and a control unit configured to use the precondition information to determine the acceleration of the vehicle traveling on the road surface and to cause the vehicle to travel at the determined acceleration. According to this aspect, the control system uses the precondition information related to the friction between the road surface and the wheels to determine the acceleration of the vehicle. Therefore, the acceleration of the vehicle can vary depending on the friction between the road surface and the wheels. In this respect, when the vehicle decelerates, the negative acceleration as the vehicle's deceleration can be determined to be smaller as the friction between the road surface and the wheels decreases. Therefore, even when the wheels slip on the road surface due to the low friction between the road surface and the wheels, the vehicle can gradually decelerate. Therefore, the accuracy of the vehicle's stopping position can be improved. When the vehicle accelerates, the positive acceleration of the vehicle can be determined to be smaller as the friction between the road surface and the wheels decreases. Therefore, even when the wheels slip on the road surface due to the low friction between the road surface and the wheels, the vehicle can gradually accelerate. Therefore, the vehicle can be stabilized in posture.

[0006] (2) In the above aspect, the precondition information may include at least one of a map showing the acceleration dependent on the friction force of the vehicle for each area in the work area and a database showing the acceleration dependent on the friction force for each work step to be performed on the vehicle. When the precondition information includes a map, the acquisition unit may be configured to further acquire vehicle position information indicating the vehicle's position, and the control unit may be configured to determine the vehicle's acceleration on the road surface by referring to the map and identifying the acceleration associated with the area including the vehicle position identified based on the vehicle position information. When the precondition information includes a database, the acquisition unit may be configured to further acquire step information indicating the work step being performed on the vehicle, and the control unit may be configured to determine the vehicle's acceleration on the road surface by referring to the database and identifying the acceleration associated with the work step identified based on the step information. According to this aspect, the control system can easily determine the vehicle's acceleration based on the known magnitude relationship of the acceleration dependent on the friction force between the road surface and the wheels in each area of ​​the work area or each work step.

[0007] (3) In the above aspects, the precondition information may include at least one of information indicating the presence or absence of road surface wetness and information indicating the degree of road surface wetness. The control unit may be configured to determine that when the road surface is wet, the acceleration of the vehicle traveling on the road surface is less than the acceleration when the road surface is not wet, and to determine that the acceleration of the vehicle traveling on the road surface decreases as the degree of road surface wetness increases. According to this aspect, the control system may change the vehicle's acceleration depending on the presence or absence of road surface wetness. According to this aspect, when the vehicle is decelerated on a wet road surface, the negative acceleration as the vehicle's deceleration can be determined to be less than the negative acceleration when the vehicle is decelerated on a dry road surface. Therefore, even when the road surface is wet and the wheels are slipping on the road surface, the vehicle can gradually decelerate. Therefore, the accuracy of the vehicle's stopping position can be improved. When the vehicle is accelerated on a wet road surface, the positive acceleration of the vehicle can be determined to be less than the positive acceleration when the vehicle is accelerated on a dry road surface. Therefore, even when the road surface is wet and the wheels are slipping on the road surface, the vehicle can gradually accelerate. Therefore, the vehicle can be stabilized in posture. According to this aspect, the control system can adjust the vehicle's acceleration based on the road surface's wetness. Specifically, when decelerating the vehicle on a wet road surface, the negative acceleration, which is the vehicle's deceleration, can be determined to decrease as the road surface's wetness increases. Therefore, even when the wheels slip on the road surface due to high wetness, the vehicle can gradually decelerate. This improves the accuracy of the vehicle's stopping position. Similarly, when accelerating the vehicle on a wet road surface, the positive acceleration can be determined to decrease as the road surface's wetness increases. Therefore, even when the wheels slip on the road surface due to high wetness, the vehicle can gradually accelerate. This stabilizes the vehicle's posture.

[0008] (4) In the above aspect, the precondition information may include information indicating the material of the road surface. The control unit may be configured to determine the vehicle's acceleration on the road surface depending on the road surface material. According to this aspect, the control system may change the vehicle's acceleration depending on the road surface material. Therefore, the accuracy of the vehicle's stopping position can be improved, and the vehicle's posture can be stabilized.

[0009] (5) In the above respects, the precondition information may include information determining the type of vehicle. The control unit may be configured to determine the acceleration of the vehicle on the road surface, depending on the type of vehicle. According to this respect, the control system may change the vehicle's acceleration depending on the type of vehicle. Therefore, the accuracy of the vehicle's stopping position can be improved, and the vehicle's posture can be stabilized.

[0010] This disclosure can be implemented in various forms other than the control system described above. For example, this disclosure can be implemented in the form of a vehicle or server that can implement at least a portion of the functions of the control system, a method for controlling a vehicle using the control system, a computer program for implementing the control method, or a non-transitory recording medium for recording the computer program. Attached Figure Description

[0011] The features, advantages, and technical and industrial significance of exemplary embodiments of the present invention will now be described with reference to the accompanying drawings, wherein similar symbols denote similar elements, and wherein:

[0012] Figure 1 This is a conceptual diagram illustrating the configuration of the control system according to the first embodiment;

[0013] Figure 2 It is a block diagram showing the configuration of the control system;

[0014] Figure 3 This is a flowchart illustrating the processing procedure for vehicle driving control according to the first embodiment;

[0015] Figure 4 This is a flowchart illustrating a vehicle control method according to a first embodiment;

[0016] Figure 5 This is a flowchart illustrating a vehicle control method according to a second embodiment;

[0017] Figure 6 This is an explanatory diagram showing a schematic configuration of the control system according to the third embodiment.

[0018] Figure 7 This is a flowchart illustrating the vehicle driving control process according to the third embodiment. Detailed Implementation

[0019] A. First Embodiment

[0020] Figure 1 This is a conceptual diagram illustrating the configuration of a control system 50 according to a first embodiment. The control system 50 includes one or more vehicles 100, a server 200, and one or more external sensors 300.

[0021] Vehicles can be vehicles that travel on wheels or on circular tracks, and can be, for example, buses, trucks, public buses, two-wheeled vehicles, four-wheeled vehicles, or construction vehicles. Vehicles include battery electric vehicles (BEVs), gasoline-powered vehicles, hybrid electric vehicles, and fuel cell electric vehicles.

[0022] Vehicle 100 can be driven autonomously. The term "autonomous driving" means driving without occupant-based driving operations. Driving operations refer to actions related to at least one of "driving," "turning," and "stopping" of vehicle 100. Autonomous driving is achieved through automated or manual remote control using devices located outside vehicle 100 or through the autonomous control of vehicle 100. Vehicle 100 driving autonomously may have onboard occupants who do not perform driving operations. Examples of occupants who do not perform driving operations include people simply sitting in the seats of vehicle 100, as well as people simultaneously performing tasks other than driving operations (such as assembly, inspection, and operation of switches) on vehicle 100. Driving by occupants through driving operations is sometimes referred to as "manned driving."

[0023] The term "remote control" herein includes "fully remote control" in which all operations of vehicle 100 are determined entirely from outside vehicle 100, and "partially remote control" in which some operations of vehicle 100 are determined from outside vehicle 100. The term "autonomous control" includes "fully autonomous control" in which vehicle 100 autonomously controls its operations without receiving any information from devices outside vehicle 100, and "partially autonomous control" in which vehicle 100 autonomously controls its operations using information received from devices outside vehicle 100.

[0024] In this embodiment, the control system 50 is used in a factory FC, where a vehicle 100 is manufactured by executing multiple manufacturing steps ST1 to ST3. The reference coordinate system of the factory FC is the global coordinate system GC, and any location in the factory FC can be represented by the X, Y, and Z coordinates in the global coordinate system GC. The factory FC includes a first location PL1 and a second location PL2. At each of the first location PL1 and the second location PL2, one or more actual steps, such as the assembly step, painting step, or inspection step in manufacturing steps ST1 to ST3, are performed. The first location PL1 and the second location PL2 are connected by a travel path TR that the vehicle 100 can travel on. The vehicle 100 moves from the first location PL1 to the second location PL2 by autonomous driving along the travel path TR. On the travel path TR, for example, the transport step in manufacturing steps ST1 to ST3 is performed to transport the vehicle 100 from the first location PL1 to the second location PL2. The configuration of the factory FC is not limited to the above.

[0025] In the factory FC, multiple external sensors 300 are installed along the driving path TR. The positions of the external sensors 300 in the factory FC are pre-adjusted. The external sensors 300 are located outside the vehicle 100. In this embodiment, the external sensors 300 are sensors that capture images of the vehicle 100 from the outside. The external sensors 300 include a communication device (not shown) and can communicate with other devices such as the server 200 via wired or wireless communication. Specifically, the external sensor 300 is a camera. The camera, used as the external sensor 300, captures images of the vehicle 100 and outputs the captured images as detection results.

[0026] Figure 2 This is a block diagram illustrating the configuration of the control system 50. The vehicle 100 includes a vehicle control unit 110 for controlling each part of the vehicle 100, an actuator assembly 120 including one or more actuators driven under the control of the vehicle control unit 110, and a communication unit 130 for communicating wirelessly with an external device such as a server 200. The actuator assembly 120 includes actuators for a drive mechanism to accelerate the vehicle 100, actuators for a steering mechanism to change the direction of travel of the vehicle 100, and actuators for a braking mechanism to decelerate the vehicle 100.

[0027] The vehicle control unit 110 is a computer including a processor 111, a memory 112, an input / output interface 113, and an internal bus 114. The processor 111, memory 112, and input / output interface 113 are connected via the internal bus 114 for bidirectional communication. An actuator assembly 120 and a communication device 130 are connected to the input / output interface 113. The processor 111 performs various functions, including those of the vehicle control unit 115, by executing a program PG1 stored in the memory 112.

[0028] The vehicle control unit 115 drives the vehicle 100 by controlling the actuator assembly 120. The vehicle control unit 115 can drive the vehicle 100 by controlling the actuator assembly 120 using a driving control signal received from the server 200. The driving control signal is a control signal used to drive the vehicle 100. In this embodiment, the driving control signal includes the acceleration and steering angle of the vehicle 100 as parameters. In other embodiments, instead of or in addition to the acceleration of the vehicle 100, the driving control signal may include the speed of the vehicle 100 as a parameter.

[0029] Server 200 is a computer including processor 201, memory 202, input / output interface 203, and internal bus 204. Processor 201, memory 202, and input / output interface 203 are connected via internal bus 204 for bidirectional communication. Communication device 205, used for communicating with various devices external to server 200, is connected to input / output interface 203. Communication device 205 can communicate wirelessly with vehicle 100 and can communicate with each external sensor 300 via wired or wireless communication. Processor 201 performs various functions by executing program PG2 stored in memory 202, including functions as acquisition unit 211 and remote control unit 212.

[0030] The acquisition unit 211 acquires various types of information, including precondition information. Precondition information relates to the friction between the road surface on which the vehicle 100 is traveling and the wheels of the vehicle 100. In this embodiment, the acquisition unit 211 acquires precondition information including a mapping and vehicle position information indicating the position of the vehicle 100. This mapping shows the acceleration of the vehicle 100 for each of regions AR1 to AR3 in the factory FC, depending on the friction between the road surface and the wheels.

[0031] The remote control unit 212 acquires detection results from sensors, uses these results to generate a driving control signal for controlling the actuator assembly 120 of vehicle 100, and sends the driving control signal to vehicle 100, thereby remotely controlling the driving of vehicle 100. At this time, the remote control unit 212 uses precondition information to determine the acceleration of vehicle 100 and causes vehicle 100 to drive at the determined acceleration. In this embodiment, the remote control unit 212 determines the acceleration of vehicle 100 by referring to a mapping map and identifying the acceleration associated with regions AR1 to AR3, including the position of vehicle 100 identified based on vehicle position information. Then, the remote control unit 212 generates a driving control signal for causing vehicle 100 to drive at the determined acceleration and sends the generated driving control signal to vehicle 100. Therefore, the remote control unit 212 remotely controls the driving of vehicle 100 with an acceleration that depends on the frictional force between the road surface and the wheels, which varies between regions AR1 to AR3 in the factory FC. In this disclosure, the term "acceleration" is a concept that includes both positive acceleration and negative acceleration, where positive acceleration is the acceleration used to accelerate a vehicle to 100 and negative acceleration is the deceleration used to decelerate a vehicle to 100.

[0032] Figure 3 This is a flowchart illustrating the processing procedure for driving control of the vehicle 100 according to the first embodiment. Figure 3During processing, the processor 201 of server 200 is used as a remote control unit 212 by executing program PG2. The processor 111 of vehicle 100 is used as a vehicle control unit 115 by executing program PG1.

[0033] In step S1, the processor 201 of the server 200 uses the detection results output from the external sensor 300 to acquire vehicle position information. The vehicle position information serves as the basis for generating driving control signals. In this embodiment, the vehicle position information includes the position and orientation of the vehicle 100 in the global coordinate system GC of the factory FC. Specifically, in step S1, the processor 201 uses captured images obtained from a camera, which is the external sensor 300, to acquire the vehicle position information.

[0034] Specifically, in step S1, processor 201 detects the external contour of vehicle 100 from the captured image, calculates the coordinates of the vehicle 100's location points in the coordinate system (i.e., local coordinate system) of the captured image, and converts the calculated coordinates into coordinates in the global coordinate system GC, thereby obtaining the position of vehicle 100. The external contour of vehicle 100 included in the captured image can be detected, for example, by using artificial intelligence to input the captured image into a detection model DM. The detection model DM is prepared, for example, internally or externally to the control system 50 and pre-stored in the memory 202 of server 200. Examples of detection models DM include trained machine learning models that have been trained to perform either semantic segmentation or instance segmentation. For example, a convolutional neural network (hereinafter referred to as "CNN") trained through supervised learning using a training dataset can be used as a machine learning model. The training dataset includes, for example, multiple training images including vehicle 100, and labels indicating whether each region in the training images refers to a region of vehicle 100 or a region of a place other than vehicle 100. During the training of the CNN, the parameters of the CNN are preferably updated to reduce the deviation between the results output from the detection model DM and the labels obtained through backpropagation. The processor 201 can obtain the orientation of the vehicle 100 by, for example, estimating the orientation based on the direction of the movement vector of the vehicle 100, the direction of which is calculated using an optical flow method from the positional changes of feature points of the vehicle 100 between frames of the captured image.

[0035] In step S2, the processor 201 of the server 200 determines the target location that the vehicle 100 is expected to move to next. In this embodiment, the target location is represented by the X, Y, and Z coordinates in the global coordinate system GC. The memory 202 of the server 200 pre-stores a reference route RR that the vehicle 100 is expected to travel along. The route is represented by nodes indicating the starting point, nodes indicating waypoints, nodes indicating the destination, and links connecting the nodes. The processor 201 uses the vehicle position information and the reference route RR to determine the target location that the vehicle 100 is expected to move to next. The processor 201 determines the target location on the reference route RR ahead of the vehicle 100's current position.

[0036] In step S3, the processor 201 of the server 200 generates a driving control signal to cause the vehicle 100 to move toward the determined target position. The processor 201 calculates the vehicle 100's speed based on the change in the vehicle 100's position and compares the calculated speed with the target speed. Typically, the processor 201 determines acceleration such that when the speed is lower than the target speed, the vehicle 100 accelerates to the acceleration determined using precondition information, and determines acceleration such that when the speed is higher than the target speed, the vehicle 100 decelerates to the deceleration determined using precondition information. When the vehicle 100 is on the reference route RR, the processor 201 determines the steering angle and acceleration to prevent the vehicle 100 from deviating from the reference route RR. When the vehicle 100 is not on the reference route RR, i.e., when the vehicle 100 deviates from the reference route RR, the processor 201 determines the steering angle and acceleration to return the vehicle 100 to the reference route RR.

[0037] In step S4, the processor 201 of the server 200 sends the generated driving control signal to the vehicle 100. The processor 201 repeats the acquisition of vehicle position information, determination of target position, generation of driving control signal, and transmission of driving control signal at predetermined intervals.

[0038] In step S5, the processor 111 of vehicle 100 receives a driving control signal sent from server 200. In step S6, the processor 111 of vehicle 100 uses the received driving control signal to control actuator assembly 120, causing vehicle 100 to travel at an acceleration and steering angle indicated by the driving control signal. The processor 111 repeats the reception of driving control signals and the control of actuator assembly 120 at predetermined intervals. Using the control system 50 according to this embodiment, the driving of vehicle 100 can be remotely controlled, and vehicle 100 can be moved without using transport equipment such as cranes or conveyors.

[0039] Figure 4 This is a flowchart illustrating a control method for a vehicle 100 according to a first embodiment. Figure 4The illustrated process is repeated at predetermined time intervals, for example, starting from the time when vehicle 100 begins driving autonomously. In step S101, the acquisition unit 211 of server 200 acquires prerequisite information including a mapping map and vehicle position information. In step S102, the remote control unit 212 of server 200 determines the acceleration of vehicle 100 by referring to the mapping map and identifying the acceleration associated with regions AR1 to AR3, including the position of vehicle 100 identified based on vehicle position information. In step S103, the remote control unit 212 generates a driving control signal for causing vehicle 100 to travel at a determined acceleration. In step S104, the remote control unit 212 sends the generated driving control signal to vehicle 100. In step S105, the vehicle control unit 115 of vehicle 100 uses the received driving control signal to control actuator assembly 120 so that vehicle 100 travels with an acceleration depending on the friction between the road surface and the wheels, which varies between regions AR1 to AR3 in the factory FC.

[0040] In the first embodiment, the control system 50 is used in a factory FC. In the factory FC, vehicle 100 is manufactured using unmanned driving. When vehicle 100 is manufactured using unmanned driving, it travels on a road surface within a building such as the factory FC, without being placed on a transport device such as a conveyor. At this time, a manufacturing step ST3 for spraying liquid onto vehicle 100 can be performed in the factory FC. Manufacturing step ST3 for spraying liquid onto vehicle 100 is, for example, a leak detection step, a cleaning step, or a painting step. The leak detection step is the step of spraying water as a liquid onto vehicle 100 to check for water entering vehicle 100. The cleaning step is the step of cleaning the body of vehicle 100 using a cleaning agent as a liquid. The painting step is the step of applying paint as a liquid to the body of vehicle 100. By performing manufacturing step ST3 for spraying liquid onto vehicle 100, vehicle 100 may travel on a road surface WR with a liquid wetness in the factory FC. The coefficient of friction between the road surface and the wheel varies between a wet road surface (WR) and a dry road surface (DR), thus the frictional force between the road surface and the wheel may vary. The coefficient of friction between the road surface and the wheel also varies depending on the degree of wetness of the road surface, thus the frictional force between the road surface and the wheel may vary. The degree of wheel slippage on the road surface can vary depending on the difference in frictional force between the road surface and the wheel. For example, the frictional force between the road surface and the wheel on a wet road surface (WR) may be less than that on a dry road surface (DR). Therefore, when driving on a wet road surface (WR), the wheel may slip more on the road surface than when driving on a dry road surface (WR). For example, the frictional force between the road surface and the wheel decreases as the degree of wetness increases. Therefore, the wheel may slip more on the road surface. Therefore, when the deceleration of vehicle 100 is the same regardless of the presence or absence of wetness and the degree of wetness, the braking distance of vehicle 100 increases with the degree of wetness. Therefore, vehicle 100 may not be able to stop at the desired position. When the acceleration of vehicle 100 is the same regardless of the presence or absence of wetness and the degree of wetness, as the degree of wetness increases, vehicle 100 may be more likely to sway and become unstable in posture.

[0041] In addition to the above, vehicle 100 can travel on painted surfaces, sheet-covered surfaces, or surfaces covered with metal plates (such as steel plates) in the factory FC, and the coefficient of friction between the road surface and the wheels can vary depending on the material of the road surface. Due to the variation in friction between the road surface and the wheels, the degree of wheel slippage on the road surface may vary. Furthermore, the normal force exerted by vehicle 100 on the road surface can vary depending on the weight of vehicle 100 and the difference in the drive system of vehicle 100 (such as 2WD or 4WD). Due to the variation in friction between the road surface and the wheels, the degree of wheel slippage on the road surface may vary. In this way, the friction between the road surface and the wheels can vary depending on factors other than the wetness of the road surface, such as differences in road material or vehicle type. Therefore, problems similar to those described above may occur.

[0042] According to the first embodiment, the control system 50 uses precondition information related to the friction between the road surface and the wheels to determine the acceleration of the vehicle 100. Therefore, the acceleration of the vehicle 100 can vary depending on the friction between the road surface and the wheels. In this configuration, when the vehicle 100 decelerates, the negative acceleration, which is the deceleration of the vehicle 100, can be determined to be smaller as the friction between the road surface and the wheels decreases. Therefore, even when the wheels slip on the road surface due to low friction between the road surface and the wheels, the vehicle 100 can gradually decelerate. Thus, the vehicle 100 can stop at the desired position. That is, the accuracy of the stopping position of the vehicle 100 can be improved. In this configuration, when the vehicle 100 accelerates, the positive acceleration of the vehicle 100 can be determined to be smaller as the friction between the road surface and the wheels decreases. Therefore, even when the wheels slip on the road surface due to low friction between the road surface and the wheels, the vehicle 100 can gradually accelerate. Thus, the vehicle 100 can be physically stable.

[0043] In the first embodiment, the manufacturing steps ST1 to ST3 to be performed at locations PL1, PL2, and TR are known in the factory FC. Therefore, the area AR3 where the road surface is wetted by liquid and the areas AR1 and AR2 where the road surface is not wetted by liquid can be distinguished in advance, and a mapping showing the acceleration depending on the road surface conditions in areas AR1 to AR3 can be created in advance. The road surface materials at locations PL1, PL2, and TR are known in the factory FC. Therefore, areas AR1 to AR3 in the factory FC can be distinguished in advance based on the differences in road surface materials, and a mapping showing the acceleration can be created in advance based on the road surface materials in areas AR1 to AR3. In this configuration, the acceleration of vehicle 100 can be easily determined based on the known magnitude relationship of the acceleration depending on the friction force between the road surface and the wheels in areas AR1 to AR3 in the factory FC.

[0044] B. Second Embodiment

[0045] As described above, the manufacturing steps ST1 to ST3 to be performed at locations PL1, PL2, and TR are known in the factory FC. In this embodiment, the acquisition unit 211 acquires prerequisite information and step information, including a database. The database shows the acceleration for each manufacturing step ST1 to ST3, which depends on the frictional force between the road surface and the wheels. The step information indicates the manufacturing steps ST1 to ST3 performed on the vehicle 100. The remote control unit 212 determines the acceleration of the vehicle 100 by referring to the database and identifying the acceleration associated with the manufacturing steps ST1 to ST3 identified based on the step information. Then, the remote control unit 212 generates a driving control signal for causing the vehicle 100 to travel at the determined acceleration and sends the generated driving control signal to the vehicle 100. Therefore, the remote control unit 212 remotely controls the vehicle 100 to travel at an acceleration that depends on the frictional force between the road surface and the wheels, which varies between manufacturing steps ST1 to ST3.

[0046] Figure 5 This is a flowchart illustrating a control method for a vehicle 100 according to a second embodiment. Figure 5 The illustrated process is repeated at predetermined time intervals, for example, starting from the time when vehicle 100 begins driving autonomously. In step S201, the acquisition unit 211 of server 200 acquires prerequisite information and step information, including a database. In step S202, the remote control unit 212 of server 200 determines the acceleration of vehicle 100 by referring to the database and identifying the acceleration associated with manufacturing steps ST1 to ST3 identified based on the step information. In step S203, the remote control unit 212 generates a driving control signal for causing vehicle 100 to travel at the determined acceleration. In step S204, the remote control unit 212 sends the generated driving control signal to vehicle 100. In step S205, the vehicle control unit 115 of vehicle 100 uses the received driving control signal to control actuator assembly 120 so that vehicle 100 travels at an acceleration that depends on the friction between the road surface and the wheels, which varies between manufacturing steps ST1 to ST3.

[0047] In the second embodiment, the manufacturing steps ST1 to ST3 to be performed at locations PL1, PL2, and TR are known in the factory FC. Therefore, a database showing the accelerations depending on the road surface material and road surface conditions (such as the presence or absence of wetness and the degree of wetness at locations PL1, PL2, and TR where manufacturing steps ST1 to ST3 are performed) can be created in advance. In this configuration, the acceleration of vehicle 100 can be easily determined based on the known magnitude relationship of the accelerations depending on the frictional force between the road surface and the wheels during manufacturing steps ST1 to ST3.

[0048] C. Third Embodiment

[0049] Figure 6 This is an explanatory diagram illustrating a schematic configuration of the control system 50v according to the third embodiment. This embodiment differs from the first embodiment in that the control system 50v does not include the server 200. In this embodiment, the vehicle 100v can be driven through autonomous control of the vehicle 100v. Unless otherwise stated, the other configurations of the third embodiment are the same as those of the first embodiment.

[0050] In this embodiment, the processor 111v of the vehicle control device 110v serves as the acquisition unit 116 and the vehicle control unit 115v by executing the program PG1 stored in the memory 112v. The acquisition unit 116 acquires various types of information, including precondition information. The vehicle control unit 115v acquires output results from sensors, uses the output results to generate a driving control signal, and outputs the generated driving control signal to operate the actuator assembly 120. Therefore, the vehicle 100v can drive autonomously. In this embodiment, the memory 112v also pre-stores the detection model DM and the reference route RR in addition to the program PG1. At this time, the vehicle control unit 115v uses the precondition information to determine the acceleration of the vehicle 100 and causes the vehicle 100 to drive at the determined acceleration. The vehicle control unit 115v determines the acceleration of the vehicle 100 by referring to a mapping map or database and identifying the acceleration that depends on the friction between the road surface and the wheels. The vehicle control unit 115v then generates a driving control signal for causing the vehicle 100 to drive at the determined acceleration and uses the generated driving control signal to control the actuator assembly 120. Therefore, the vehicle control unit 115v autonomously controls the vehicle 100 to travel at an acceleration that depends on the friction between the road surface and the wheels.

[0051] Figure 7 This is a flowchart illustrating the processing procedure for driving control of a vehicle 100v according to a third embodiment. Figure 7 During the processing, the processor 111v of vehicle 100v is used as vehicle control unit 115v by executing program PG1.

[0052] In step S901, the processor 111v of the vehicle control device 110v acquires vehicle position information using detection results output from the camera, which is an external sensor 300. In step S902, the processor 111v determines the target position that the vehicle 100v is expected to move to next. In step S903, the processor 111v generates a driving control signal to cause the vehicle 100v to move toward the determined target position. In step S904, the processor 111v uses the generated driving control signal to control the actuator group 120 so that the vehicle 100v moves based on the parameters indicated by the driving control signal. The processor 111v repeats the acquisition of vehicle position information, determination of target position, generation of driving control signal, and control of actuators at predetermined intervals. Using the control system 50v according to this embodiment, the vehicle 100v can move autonomously even if it is not remotely controlled by the server 200.

[0053] D. Other embodiments

[0054] (D1) Acquisition units 116 and 211 can acquire precondition information including information indicating the presence or absence of road surface wetness. In this case, when the road surface is wet, control units 115v and 212 can determine that the acceleration of vehicle 100 and 100v is less than the acceleration when the road surface is not wet. In this configuration, control systems 50 and 50v can change the acceleration of vehicle 100 and 100v depending on the presence or absence of road surface wetness. Therefore, when vehicle 100 and 100v decelerate on a wet road surface WR, the negative acceleration as the deceleration of vehicle 100 and 100v can be determined to be less than the negative acceleration when vehicle 100 and 100v decelerate on a dry road surface DR. Therefore, even when the road surface is wet and the wheels slip on the road surface, vehicle 100 and 100v can gradually decelerate. Therefore, the accuracy of the stopping position of vehicle 100 and 100v can be improved. When vehicle 100 and 100v are accelerated on a wet surface WR, the positive acceleration of vehicle 100 and 100v can be determined to be less than the positive acceleration of vehicle 100 and 100v when accelerated on a dry surface DR. Therefore, even when the surface is wet and the wheels are slipping on the surface, vehicle 100 and 100v can gradually accelerate. Therefore, vehicle 100 and 100v can maintain a stable posture.

[0055] (D2) Acquisition units 116 and 211 can acquire precondition information including information indicating the degree of road surface wetness. In this case, control units 115v and 212 can determine that the acceleration of vehicles 100 and 100v decreases as the road surface wetness increases. In this configuration, control systems 50 and 50v can change the acceleration of vehicles 100 and 100v depending on the degree of road surface wetness. Therefore, when vehicles 100 and 100v are decelerated on a wet road surface WR, the negative acceleration of vehicle 100 and 100v's deceleration can be determined to decrease as the road surface wetness increases. Therefore, even when the wheels slip on the road surface due to high road surface wetness, vehicles 100 and 100v can gradually decelerate. Therefore, the accuracy of the stopping position of vehicles 100 and 100v can be improved. When vehicles 100 and 100v are accelerated on a wet road surface WR, the positive acceleration of vehicles 100 and 100v can be determined to decrease as the road surface becomes wetter. Therefore, even when the wheels slip on the road surface due to high wetness, vehicles 100 and 100v can gradually accelerate. Thus, vehicles 100 and 100v can maintain a stable posture.

[0056] (D3) Acquisition units 116 and 211 can acquire precondition information, including information indicating the material of the road surface. In this case, control units 115v and 212 can determine the acceleration of vehicle 100 and 100v depending on the material of the road surface. In this configuration, control systems 50 and 50v can change the acceleration of vehicle 100 and 100v depending on the material of the road surface. Therefore, the accuracy of the stopping position of vehicle 100 and 100v can be improved, and the attitude of vehicle 100 and 100v can be stabilized.

[0057] (D4) Acquisition units 116 and 211 can acquire precondition information including information determining the type of vehicle 100, 100v. In this case, control units 115v and 212 can determine the acceleration of vehicle 100, 100v depending on the type of vehicle 100, 100v. For example, as the weight of vehicle 100, 100v decreases, the wheels may slip more on the road surface. Therefore, acquisition units 116 and 211 can acquire precondition information including information related to the weight of vehicle 100, 100v as information to determine the type of vehicle 100, 100v. In this case, control units 115v and 212 can determine that the acceleration of vehicle 100, 100v decreases as the weight of vehicle 100, 100v decreases. For example, when the drive system of vehicle 100, 100v is 2WD, the wheels may slip more on the road surface than when the drive system of vehicle 100, 100v is 4WD. Therefore, acquisition units 116 and 211 can acquire prerequisite information, including information related to the drive system of vehicles 100 and 100v, as information to determine the type of vehicles 100 and 100v. In this case, when the drive system of vehicles 100 and 100v is 2WD, control units 115v and 212 can determine that the acceleration of vehicles 100 and 100v is less than the acceleration when the drive system of vehicles 100 and 100v is 4WD. In this configuration, control systems 50 and 50v can change the acceleration of vehicles 100 and 100v depending on the type of vehicles 100 and 100v determined by the weight of vehicles 100 and 100v, drive system, etc. Therefore, the accuracy of the stopping position of vehicles 100 and 100v can be improved, and the posture of vehicles 100 and 100v can be stabilized. The information for determining the type of vehicles 100 and 100v is not limited to the above, and can be identification symbols or numbers used to identify vehicles 100 and 100v, or other information such as the number and arrangement of wheels.

[0058] (D5) Control systems 50 and 50v can be used outside the factory FC where vehicles 100 and 100v are manufactured. That is, control systems 50 and 50v can control vehicles 100 and 100v after shipment. When control systems 50 and 50v are used outside the factory FC, the term "factory" in this disclosure may be appropriately replaced with "workplace," and the term "manufacturing step" in this disclosure may be appropriately replaced with "work step." In this configuration, even in a workplace (such as a vehicle inspection station) outside the factory FC, control systems 50 and 50v can use precondition information related to the friction between the road surface and the wheels to determine the acceleration of vehicles 100 and 100v. Therefore, even in a workplace (such as a vehicle inspection station) outside the factory FC, control systems 50 and 50v can change the acceleration of vehicles 100 and 100v depending on the friction between the road surface and the wheels. Therefore, the accuracy of the stopping position of vehicles 100 and 100v can be improved, and vehicles 100 and 100v can be stabilized in posture even in work areas other than factory FC (such as vehicle inspection stations).

[0059] (D6) At least a portion of the functionality of server 200 can be implemented as a function of vehicle control devices 110, 110v, or as a function of another device such as external sensor 300. In this case, the configuration of control systems 50, 50v can be appropriately modified.

[0060] (D7) In each of the above embodiments, the external sensor 300 is not limited to a camera, but can be, for example, a distance measuring device. The distance measuring device is, for example, a light detection and ranging (LiDAR) device. In this case, the detection result output from the external sensor 300 can be three-dimensional point cloud data representing vehicles 100 and 100v. In this case, the server 200 or vehicles 100 and 100v can use the three-dimensional point cloud data as the detection result and pre-prepared reference point cloud data to obtain vehicle position information through template matching.

[0061] (D8) In the first and second embodiments, server 200 performs the process from acquiring vehicle location information to generating driving control signals. Alternatively, vehicle 100 may perform at least a portion of the process from acquiring vehicle location information to generating driving control signals. For example, the following configurations (1) to (3) may be used.

[0062] (1) Server 200 can acquire vehicle location information, determine the target location that vehicle 100 is expected to move to next, and generate a route from the current location of vehicle 100 indicated by the acquired vehicle location information to the target location. Server 200 can generate a route to the target location between the current location and the destination, or it can generate a route to the destination. Server 200 can send the generated route to vehicle 100. Vehicle 100 can generate a driving control signal to drive on the route received from server 200, and use the generated driving control signal to control actuator assembly 120.

[0063] (2) Server 200 can acquire vehicle location information and send the acquired vehicle location information to vehicle 100. Vehicle 100 can determine the target location that vehicle 100 is expected to move to next, generate a route from the current location of vehicle 100 indicated by the received vehicle location information to the target location, generate a driving control signal so that vehicle 100 travels on the generated route, and use the generated driving control signal to control actuator group 120.

[0064] (3) In the above configurations (1) and (2), the internal sensors can be installed on the vehicle 100, and the detection results output from the internal sensors can be used for at least one of route generation and driving control signal generation. The internal sensors are installed on the vehicle 100. Examples of internal sensors may include sensors that detect the motion state of the vehicle 100, sensors that detect the operating state of various components of the vehicle 100, and sensors that detect the environment around the vehicle 100. Specific examples of internal sensors may include cameras, LiDAR devices, millimeter-wave radar, ultrasonic sensors, global positioning system (GPS) sensors, accelerometers, and gyroscopes. For example, in the above configuration (1), the server 200 can obtain detection results from the internal sensors and reflect the detection results from the internal sensors in the route when generating the route. In the above configuration (1), the vehicle 100 can obtain detection results from the internal sensors and reflect the detection results from the internal sensors in the driving control signal when generating the driving control signal. In the above configuration (2), the vehicle 100 can obtain detection results from the internal sensors and reflect the detection results from the internal sensors in the route when generating the route. In the above configuration (2), the vehicle 100 can obtain the detection results from the internal sensors and reflect the detection results from the internal sensors in the driving control signal when generating the driving control signal.

[0065] (D9) In the third embodiment, the internal sensor may be mounted on the vehicle 100v, and the detection results output from the internal sensor may be used for at least one of route generation and driving control signal generation. For example, the vehicle 100v may acquire the detection results from the internal sensor and reflect the detection results from the internal sensor in the route when generating the route. The vehicle 100v may acquire the detection results from the internal sensor and reflect the detection results from the internal sensor in the driving control signal when generating the driving control signal.

[0066] (D10) In the third embodiment, vehicle 100v uses detection results from external sensor 300 to acquire vehicle position information. Internal sensors can be mounted on vehicle 100v, and vehicle 100v can use detection results from internal sensors to acquire vehicle position information, determine the expected target location to which vehicle 100v will next move, generate a route from the current location of vehicle 100v indicated by the acquired vehicle position information to the target location, generate a driving control signal to cause vehicle 100v to travel on the generated route, and use the generated driving control signal to control actuator assembly 120. In this case, vehicle 100v can travel without using detection results from external sensor 300. Vehicle 100v can acquire target arrival time and traffic congestion information from outside vehicle 100v and reflect either the target arrival time or traffic congestion information in at least one of the route and driving control signal. All functional components of control system 50v can be located in vehicle 100v. That is, the processing implemented by control system 50v in this disclosure can be implemented by vehicle 100v alone.

[0067] (D11) In the first and second embodiments, server 200 automatically generates a driving control signal to be sent to vehicle 100. Server 200 can generate the driving control signal to be sent to vehicle 100 in response to an operation by an external operator outside vehicle 100. For example, the external operator can operate a control device including a display showing images captured from external sensors 300, a steering wheel, accelerator pedal, and brake pedal for remotely operating vehicle 100, and a communication device for communicating with server 200 via wired or wireless communication, and server 200 can generate the driving control signal in response to the operation performed on the control device.

[0068] (D12) In each of the above embodiments, vehicles 100, 100v only need to include components that enable movement via autonomous driving, and may be in the form of a platform, for example, including the following components. Specifically, vehicles 100, 100v only need to include at least vehicle control units 110, 110v and actuator group 120 to perform three functions via autonomous driving, including "running," "turning," and "stopping." To enable vehicles 100, 100v to acquire information from the outside for autonomous driving, vehicles 100, 100v only need to include communication device 130. That is, at least a portion of internal components such as driver's seat or dashboard, at least a portion of external components such as bumpers or fenders, or body shells may be omitted from vehicles 100, 100v that can move via autonomous driving. In this configuration, remaining components, such as the body shell, can be installed on vehicles 100 and 100v before they are shipped from the factory FC, or they can be installed on vehicles 100 and 100v after they are shipped from the factory FC, provided that the remaining components, such as the body shell, are not installed on the vehicles 100 and 100v. Components can be installed on vehicles 100 and 100v from any side, such as the top, bottom, front, rear, right, or left side, and can be installed from the same side or from different sides. Similarly, in the form of a platform, the positions can be determined in the same way as those of vehicles 100 and 100v according to the first embodiment.

[0069] (D13) Vehicles 100 and 100v can be manufactured by combining multiple modules. A module is a unit consisting of one or more parts grouped according to the structure and function of vehicles 100 and 100v. For example, the platform of vehicles 100 and 100v can be manufactured by combining a front module constituting the front of the platform, a central module constituting the central part of the platform, and a rear module constituting the rear of the platform. The number of modules constituting the platform is not limited to three and can be two or fewer or four or more. In addition to or in place of the platform, parts of vehicles 100 and 100v other than the platform can be modularized. Various modules can include any external parts, such as bumpers or grilles, or any internal parts, such as seats or consoles. For example, such modules can be manufactured by welding, connecting multiple parts using fasteners, etc., or by casting at least a portion of the module integrally molded into a single part. The molding method used to integrally mold at least a portion of the module into a single part is also known as gigacasting or megacasting. Using gigafactory casting, each part of the vehicle 100, 100v, which has so far been formed by joining multiple components, can be formed as a single part. For example, the front module, central module, and rear module can be manufactured using gigafactory casting.

[0070] (D14) The unmanned transportation of vehicles 100 and 100v is called “self-propelled transportation”. The configuration used to realize self-propelled transportation is called “vehicle remote control autonomous driving transportation system”. The method of producing vehicles 100 and 100v using self-propelled transportation is called “self-propelled production”. For example, in self-propelled production, at least part of the transportation of vehicles 100 and 100v in the factory FC that manufactures vehicles 100 and 100v is realized by self-propelled transportation.

[0071] (D15) In each of the above embodiments, some or all of the functions and processes implemented by software may be implemented by hardware. Some or all of the functions and processes implemented by hardware may be implemented by software. Examples of hardware that can be used to implement the various functions in each of the above embodiments include various types of circuits, such as integrated circuits and discrete circuits.

[0072] This disclosure is not limited to the embodiments described above, and can be implemented in various configurations without departing from the spirit of this disclosure. For example, in order to solve some or all of the above problems or achieve some or all of the above effects, the technical features in each embodiment corresponding to the technical features in each aspect described in the "Summary of the Invention" can be appropriately replaced or combined. When technical features are not described herein, they can be appropriately omitted if necessary.

Claims

1. A control system configured to control a vehicle configured to operate autonomously, the control system comprising: The acquisition unit is configured to acquire precondition information related to the friction between the road surface on which the vehicle is traveling and the wheels of the vehicle. as well as The control unit is configured to use the precondition information to determine the acceleration of the vehicle traveling on the road surface, and to cause the vehicle to travel at the determined acceleration.

2. The control system according to claim 1, wherein: The prerequisite information includes at least one of a map showing the acceleration dependent on the friction force for each area in the work area for vehicle movement and a database showing the acceleration dependent on the friction force for each work step to be performed on the vehicle. When the prerequisite information includes the mapping graph. The acquisition unit is configured to further acquire vehicle location information indicating the location of the vehicle, and The control unit is configured to determine the acceleration of the vehicle traveling on the road surface by referring to the mapping map and identifying accelerations associated with a region including the vehicle's position identified based on the vehicle's position information; and When the prerequisite information includes the database. The acquisition unit is configured to further acquire step information indicating the operation steps being performed on the vehicle, and The control unit is configured to determine the acceleration of the vehicle traveling on the road surface by referring to the database and identifying the acceleration associated with the operation step identified based on the step information.

3. The control system according to claim 1, wherein: The precondition information includes at least one of information indicating the presence or absence of moisture on the road surface and information indicating the degree of moisture on the road surface; and The control unit is configured as follows: When the road surface is wet, it is determined that the acceleration of the vehicle traveling on the road surface is less than the acceleration when the road surface is not wet. It was determined that the acceleration of the vehicle traveling on the road surface decreases as the road surface becomes wetter.

4. The control system according to claim 1, wherein: The prerequisite information includes information indicating the material of the road surface; and The control unit is configured to determine the acceleration of the vehicle traveling on the road surface, depending on the material of the road surface.

5. The control system according to claim 1, wherein: The prerequisite information includes information determining the type of the vehicle; and The control unit is configured to determine the acceleration of the vehicle traveling on the road surface, depending on the type of the vehicle.

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