VEHICLE CONTROL DEVICE

Abstract

Vehicle control device comprising: - an autonomous driving control unit (20) configured to determine a travel route when autonomous driving is implemented based on environmental information and position information of a vehicle, and to calculate and output a control value according to the travel route; - a monitoring unit (21) configured to monitor the calculation time of the autonomous driving control unit (20); and - a switching unit (22) configured to receive the output from the autonomous driving control unit (20) and to output the control value or an alternative control value instead of the control value, based on an instruction from the monitoring unit (21), wherein the monitoring unit (21) is configured to, when the calculation time exceeds a threshold value, notify the autonomous driving control unit (20) of a calculation interruption request, notify the switching unit (22) of a control value switching request, make a determination as to whether or not the safety of the vehicle itself is ensured with the alternative control value on the basis of the environmental information and the position information, and notify the switching unit (22) of the safety determination result, and the switching unit (22) is configured to output the control value or the alternative control value based on at least the control value switching request and the determination result of the safety, wherein the control value is acquired by obtaining an optimal value by repeating a loop calculation a plurality of times, and if the optimal value is not detected before the calculation interruption request is transmitted from the monitoring unit (21), the autonomous driving control unit is configured to interrupt the loop calculation by being notified of the calculation interruption request and determine whether a control value in the middle of the calculation can be output as the alternative control value.

Description

Technical area

[0001] The present invention relates to a vehicle control device, in particular a vehicle control device that realizes fail-safe operation. State of the art

[0002] On-board systems are equipped with a wide variety of electronic devices. The number of control devices controlling these devices is increasing due to the increasing number of functions and complexities in recent times. In particular, in autonomous driving systems, whose research and development is accelerating these days, a system has been developed that realizes highly autonomous driving by linking the vehicle's engine control, braking control, and steering control.

[0003] Such an autonomous driving system includes: an autonomous driving control unit that generates optimal control parameters from the environmental conditions, a vehicle engine controller, an engine control unit that implements braking control and steering control, a braking control unit, and a steering control unit. If an abnormality occurs in any part of an autonomous driving system, autonomous driving cannot continue, so maintenance operation (fault operation), which is an operation performed until a state where safety is ensured, and transition (fail-safe operation) to a safe state are necessary.

[0004] In addition, there are levels of autonomous driving defined by the International Society of Automotive Engineers (SAE) for autonomous driving, with the scope of responsibility the system is expected to assume increasing as the level increases. Furthermore, the scope of application expands from the area limited to highways or expressways to general roads and their urban areas, further complicating the algorithms installed in the autonomous driving control unit.

[0005] To solve such a problem, Patent Document 1 proposes a mechanism for reducing the processing load and power consumption by controlling the detection frequency of the surrounding information according to the traveling environment of the vehicle.

[0006] Furthermore, Patent Document 2 proposes a mechanism for monitoring the execution order and execution time of a control program. Prior art documentsPatent documents Patent Document 1: Japanese Patent Application Laid-Open No. JP 2016-113092 A Patent Document 2: Japanese Patent JP 5 846 342 B1 SummaryProblem to be solved with the invention

[0007] In Patent Document 1, the computational processing load is reduced by changing the detection frequency of the surrounding information. However, there is a problem that if the calculation for detecting the surrounding information does not fit the timing of the control cycle, the judgment and control for autonomous driving cannot be performed.

[0008] In Patent Document 2, the execution time is monitored, and when the threshold is exceeded, alternative control is performed with a predetermined value. However, since the alternative control is fixed, there is a problem that flexible control cannot be performed that takes into account the environmental conditions necessary for autonomous driving.

[0009] The present invention has been conceived to solve the above-mentioned problems, and its object is to provide a vehicle control device capable of maintaining autonomous driving by outputting a control value according to a situation even when the computation load increases. Ways to solve the problem

[0010] According to the present invention, a vehicle control device comprises: an autonomous driving control unit configured to determine a travel route when implementing autonomous driving based on environmental information and position information of a vehicle, and to calculate and output a control value according to the travel route, a monitoring unit configured to monitor the calculation time of the autonomous driving control unit, and a switching unit configured to receive the output from the autonomous driving control unit and output the control value or an alternative control value instead of the control value based on an instruction from the monitoring unit, wherein the monitoring unit is configured to, when the calculation time exceeds a threshold,the autonomous driving control unit notifies the switching unit of a calculation interruption request, notifies the switching unit of a control value switching request, makes a determination as to whether or not the safety of the vehicle itself is ensured with the alternative control value based on the environmental information and the position information, and notifies the switching unit of the safety determination result, and the switching unit is configured to output the control value or the alternative control value based on at least the control value switching request and the safety determination result. Effects of the invention

[0011] In the vehicle control device according to the present invention, even if the calculation time exceeds the threshold and the calculation load increases, the autonomous driving can be maintained by outputting the alternative control value according to the situation. Short description of the drawings

[0012] The drawings show: Fig. 1 is a block diagram illustrating a configuration of a vehicle control device according to the first embodiment of the present invention. Fig. 2 is a flowchart illustrating a switching determination in a monitoring unit of the vehicle control device according to the first embodiment of the present invention. Fig. 3 is a flowchart illustrating a calculation process of a control value of an actuator in an autonomous driving control unit of the vehicle control device according to the first embodiment of the present invention. Fig. 4 is a flowchart illustrating a switching process in a switching unit of the vehicle control device according to the first embodiment of the present invention. Fig. 5 is a block diagram illustrating a configuration of a vehicle control device according to the second embodiment of the present invention. Fig. 6 is a flowchart illustrating a switching process in a switching unit of the vehicle control device according to the second embodiment of the present invention. Fig. 7 is a graph illustrating an example of a method for determining an estimated control value based on a history value stored in a control history holding unit of the vehicle control device according to the second embodiment of the present invention. Fig. 8 is a block diagram illustrating a configuration of a vehicle control device according to the third embodiment of the present invention. Fig. 9 is a flowchart illustrating a switching process in a switching unit of the vehicle control device according to the third embodiment of the present invention. Fig. 10 is a block diagram illustrating a hardware configuration implementing the vehicle control device according to the first to third embodiments of the present invention. Fig. 11 is a block diagram illustrating a hardware configuration implementing the vehicle control device according to the first to third embodiments of the present invention. Description of embodimentsFirst embodimentDevice configuration

[0013] Fig. 1 is a functional block diagram illustrating a configuration of a vehicle control device 10 according to the first embodiment of the present invention.The vehicle control device 10, which is installed on a vehicle (not shown), includes: an autonomous driving control unit 20 that receives various information from a plurality of surrounding information sensing units 30, 31, and 32 and a subject vehicle position information sensing unit 40, which are also mounted on the vehicle, via an on-board network 80; a monitoring unit 21 that is connected to the surrounding information sensing units 30, 31, and 32, the vehicle position information sensing unit 40, and the autonomous driving control unit 20; a switching unit 22 that is connected to the autonomous driving control unit 20 and the monitoring unit 21; a steering control unit 50 that is connected to the switching unit 22 via the on-board network 81; a braking control unit 60; and an accelerator pedal control unit 70.

[0014] Although the environmental information acquisition units 30 to 32 are Fig. 1, the number is not limited thereto, and they are selected from various sensors such as a camera, a millimeter-wave radar and a sonar, a vehicle-to-vehicle communication module, a road-to-vehicle communication module, and the like.

[0015] An example of the vehicle position information acquisition unit 40 includes a global navigation satellite system (GNSS) receiver, such as the global positioning system (GPS), which obtains information of the surroundings by combining the received vehicle position information with a high-precision map, such as a dynamic map.

[0016] The autonomous driving control unit 20 collects the environmental information obtained from the environmental information acquisition units 30 to 32 and the position information obtained from the subject vehicle position information acquisition unit 40, generates a travel route that the subject vehicle takes in the autonomous driving implementation, and calculates the control value according to the travel route, such as a target steering wheel angle, a motor drive value, and a brake drive value. The calculation result is input to the switching unit 22.

[0017] In the switching unit 22, switching is performed between a process of the calculation result sent to the steering control unit 50, the brake control unit 60, and the accelerator control unit 70 via the on-board network 81 and a process of the previous value sent to the steering control unit 50, the brake control unit 60, and the accelerator control unit 70 via the on-board network 81, so that autonomous driving is implemented with the control of various actuators being performed.

[0018] The monitoring unit 21 monitors the calculation time by the autonomous driving control unit 20, and when the calculation time does not fit into a calculation cycle time of the control value, for example, within 100 ms, the monitoring unit 21 requests the autonomous driving control unit 20 to interrupt the calculation and requests the switching unit 22 to switch the output of the control value.

[0019] In addition, the monitoring unit 21 determines whether the control value taking a value in the middle of the calculation or a previous value causes a safety problem based on the environmental situation, and sends the determination result to the switching unit 22. The switching unit 22 is equipped with the previous value holding unit 23 for storing the control value output from the autonomous driving control unit 20 for each calculation cycle of the control value so that it can be used as the previous value, and outputs an appropriate control value according to the procedure described later. Operation

[0020] First, the switching determination is made in the monitoring unit 21 using the Fig. 2. The monitoring unit 21 synchronizes with the calculation of the autonomous driving control unit 20 and monitors the calculation time of the autonomous driving control unit 20. Various algorithms exist for calculating the control value of the actuator for implementing autonomous driving; here, an algorithm that finds the optimal value by solving the optimization problem is used.

[0021] The optimal value is obtained by repeating loop operations multiple times. In such a case, if the value does not converge to the optimal value, the calculation time may take longer regardless of the repetition. If the calculation time is too long, the control value will not be output from the autonomous driving control unit 20 for a long time, which will hinder autonomous driving.

[0022] In step S101, with respect to the preset calculation time threshold, the monitoring unit 21 determines whether the calculation time in the autonomous driving unit 20 exceeds the threshold, and if the calculation time exceeds the threshold (YES), the monitoring unit 21 notifies the autonomous driving control unit 20 of the calculation interruption request in step S102. This prevents the calculation time from being extended indefinitely to infinity.

[0023] Then, in step S103, a control value switching request is transmitted to the switching unit 22. Thereafter, the monitoring unit 21 notifies the switching unit 22 of the result of the safety determination based on the environmental information obtained from the environmental information acquisition units 30 to 32 and the position information obtained from the vehicle position information acquisition unit 40 (step S104).

[0024] The safety determination is performed from the viewpoint that even if the control value of the calculation result in the previous calculation cycle or an alternative control value that is the control value of the intermediate calculation result is an alternative control value, the following is performed: Whether it can be guaranteed that a transition to the situation where no contact with obstacles occurs, the situation where no lane departure occurs, or the like, and the determination result of “safety can be ensured” or “safety cannot be ensured” is transmitted to the steering control unit 50, the brake control unit 60, and the accelerator control unit 70.

[0025] In this way, the minimum safety can be ensured by using a situation in which there is no contact with an obstacle or a situation in which there is no deviation from the lane as a reference for safety.

[0026] As an exemplary method for the determination, for example, it can be determined based on the presence or absence of other vehicles and obstacles and environmental information such as whether it is a straight road or a curved road, whether there is an intersection or whether there is a blind spot in the traveling direction, the target route of the subject vehicle and the current control value.

[0027] That is, the autonomous driving control unit 20 obtains the optimal value of the control value by performing loop calculation, and the threshold of the calculation time used in step S101 is set to be shorter than the calculation cycle. For example, when the calculation cycle is 100 ms, the threshold is set to 90 ms, which ensures the processing time in the autonomous driving control unit 20 and the output selection time in the switching unit 22. Even in the middle of the calculation process, where the calculation process for solving the optimization problem has not yet converged, most of the loop calculations are fully completed, and the operation result can be a control value close to the optimal value.

[0028] By using an algorithm that obtains the optimal value by solving the optimization problem when calculating the control value, actuator control can be implemented using an alternative control value, even if the control value is in the middle of the calculation. If safety can be ensured from the environmental information, this alternative control value can then be used for actuator control.

[0029] If it is determined in step S101 that the calculation time of the autonomous driving control unit 20 does not exceed the threshold (NO), it is determined in step S105 whether the calculation of the autonomous driving control unit 20 is complete, and the calculation is performed. If completed, a sequence of processes ends when the calculation is complete, and the process of step S101 is repeated if the calculation is not complete.

[0030] Although the threshold value of the calculation time is set in advance to a fixed value according to the calculation cycle of the autonomous driving control unit 20, a variable value may also be adopted. By setting the threshold value to a variable value, a larger value for the calculation time can be ensured in the autonomous driving control unit 20. The monitoring unit 21 changes the threshold value, and the unit determines the value based on the environmental information, the processing by the autonomous driving control unit 20, and the selection time output by the switching unit 22.

[0031] Next, the calculation process of the control value of the actuator in the autonomous driving control unit 20 is described with reference to the Fig. 3. As described above, the autonomous driving control unit 20 adopts a method for obtaining the optimal value by repeating the loop calculation and obtains the optimal value by repeating the in-loop calculation process in step S201. For the in-loop calculation process, for example, an optimization method such as the well-known steepest descent method can be adopted.

[0032] The in-loop arithmetic process of step S201 is one loop calculation among a plurality of loop calculations of the calculation processes for solving the optimization problem, which determines whether the calculation completion condition in step S202 is satisfied by the in-loop calculation process of step S201, that is, for each loop operation. The calculation completion condition in step S202 means that all calculation processes for solving the optimization problem are completed, and this being satisfied means that the optimal value of the actuator control value has been obtained.

[0033] If the calculation termination condition is met in step S202 (YES), the calculation result is output in step S206 to terminate the sequence of processes. On the other hand, if the operation termination condition cannot be met in step S202 (NO), the process proceeds to step S203, and it is checked whether the calculation interruption request is transmitted from the monitoring unit 21.

[0034] The monitoring unit 21 determines whether the calculation time in the autonomous driving control unit 20 exceeds the threshold, and transmits the calculation interruption request when the calculation time exceeds the threshold. This threshold is set as described above, but slightly shorter than the calculation cycle of the calculation process for solving the optimization problem.

[0035] Even if the calculation process for solving the optimization problem does not converge, the monitoring unit 21 does not issue a calculation interruption request notification until much of the loop calculation is completed. If the monitoring unit 21 has not notified the calculation interruption request (NO), the process returns to step S201, and the next intra-loop calculation process is performed.

[0036] On the other hand, if the monitoring unit 21 has notified the operation interruption request (YES), the monitoring unit 21 stops the in-loop calculation process and determines whether the control value of the intermediate calculation result can be output as an alternative control value in step S204. This determination is made, for example, from the perspective of whether or not the control value has reached a value that can control the vehicle even if the result is in the middle of the calculation.

[0037] As a method for determination, a method is applicable in which the determination is made by comparing the current control value and the target route of the subject vehicle, and by comparing it with the control value uniquely calculated by proportional-integral-derivative (PID) control based on the current control value. The above-mentioned PID control is an example, and the control value for comparison can be obtained by any conventional calculation.

[0038] If it is determined in step S204 that the control value of the intermediate calculation result can be output as an alternative control value (YES), then the intermediate result is output to the switching unit 22 in step S205. On the other hand, if it is determined in step S204 that the control value of the intermediate calculation result cannot be output as an alternative control value (NO), the intermediate result output rejection information is transmitted to the switching unit 22 in step S207, and then the control value (emergency stop control value) for the emergency stop measure is output to the switching unit 22 in step S208.

[0039] Next, the switching process in the switching unit 22 is carried out using the Fig. 4. First, the switching unit 22 checks whether the control value switching request has been transmitted from the monitoring unit 21 in step S301. If it is confirmed in step S301 that the control value switching request has not been transmitted (NO), the switching unit 22 selects and outputs the control value of the regular calculation result output from the autonomous driving control unit 20 in step S305.

[0040] Again, if it is confirmed in step S301 that the control value switching request has been transmitted (YES), the switching unit 22 checks the safety determination result transmitted from the monitoring unit 21 in step S302. If safety cannot be ensured in step S302 (NO), in step S306 the switching unit 22 selects the control value for emergency stop action output from the autonomous driving control unit 20 and outputs it as an alternative control value. Examples of emergency stop actions include "stop on the shoulder" and "stop on the spot."

[0041] In this way, when safety cannot be guaranteed, the control value for emergency stop measures is output so that safety can be guaranteed.

[0042] In step S302, if the safety determination result shows that safety can be ensured (YES), the switching unit 22 checks whether the intermediate result output rejection information is sent from the autonomous driving control unit 20 (step S303). If it is confirmed in step S303 that intermediate result output rejection information has not been sent (NO), the switching unit 22 selects the control value of the intermediate result of the calculation and outputs it as an alternative control value in step S307.

[0043] Again, when it is confirmed in step S303 that the intermediate result output rejection information has been sent (YES), the switching unit 22 selects the control value of the calculation result in the previous calculation cycle stored in the previous value holding unit 23 in step S304 and outputs it as an alternative control value.

[0044] As described above, in the vehicle control device 10 of the first embodiment, the monitoring unit 21 monitors the calculation time of the autonomous driving control unit 20 in synchronization with the calculation of the autonomous driving control unit 20, and when the calculation time does not fall within the calculation cycle time, it requests the autonomous driving control unit 20 to interrupt the calculation and requests the switching unit 22 to switch to output the control value.

[0045] When switching to output the control value is requested, the switching unit 22 selects the control value of the intermediate calculation result or the control value calculated in the previous calculation cycle and outputs it as an alternative control value, so that even if the calculation load increases, the control value is output according to the condition and autonomous driving can be maintained. It is likely that the control value calculated in the previous calculation cycle is a control value relatively close to the control value in the regular calculation result, and in this case, suitable autonomous driving can be maintained. Second embodimentDevice configuration

[0046] Fig. Fig. 5 is a functional block diagram illustrating a configuration of a vehicle control device 10A according to the second embodiment of the present invention. The difference from the vehicle control device 10 shown in Fig. 1 is that the switching unit 22 is provided with a control history holding unit 24 instead of the previous value holding unit 23, and the same components as those of the device 10 are designated by the same reference numerals, and the repeated description will be omitted.

[0047] The control history holding unit 24 not only stores the control value output from the autonomous driving control unit 20 for each calculation cycle of the control value as the previous value, but also stores the control value for a certain period earlier than the previous value as the history value. Operation

[0048] The switching determination by the monitoring unit 21, which is made using the flowchart of Fig. 2, and the calculation process of the control value of the actuator by the autonomous driving control unit 20, which is carried out using the flowchart of Fig. 3 in the description of the vehicle control device 10 of the first embodiment are the same in the vehicle control device 10A of the second embodiment, but the switching process in the switching unit 22 is different from that of the first embodiment.

[0049] That is, in the flow chart according to Fig. 6, which illustrates the switching process in the switching unit 22, the following applies: Although the processes of steps S401, S402 and S403 are the same as the processes of steps S301, S302 and S303 in the flowchart shown in Fig. 4, the difference from the vehicle control device 10 of the first embodiment is that in step S403, when it is confirmed that the intermediate result output rejection information is sent from the autonomous driving control unit 20 (YES), the estimated control value calculated based on the history value stored in the control history holding unit 24 is selected and output as an alternative control value in step S404.

[0050] As a result of checking the safety determination result transmitted from the monitoring unit 21 in step S402, it is definitely the case that there is no safety issue; therefore, in step S404, the estimated control value calculated from the past history value can be used as an alternative control value. Therefore, an alternative control value can be output according to the vehicle state and environmental information, instead of the control value calculated in the previous calculation cycle.

[0051] The processes of steps S405, S406 and S407 are the same as the processes of steps S305, S306 and S307 in the Fig. 4 illustrated flowchart.

[0052] Fig. 7 is a graph illustrating an example of a method for determining the estimated control value with reference to the history values ​​stored in the control history holding unit 24. Fig. Figure 7 illustrates the past control values ​​in chronological order. The horizontal axis represents the time course. The vertical axis represents the control value. • denotes the past control values, which are the actual values. o denotes an estimated value (estimated control value) calculated by extrapolation from the past control values. In step S404, the estimated value is output as an alternative control value.

[0053] The control values ​​stored in the control history holding unit 24 need not be all of the past controls, and may be sparsely stored at appropriate intervals. Furthermore, the estimated value is not limited to the value extrapolated from the history of past control values. For example, the control value may be determined using the engine control value, in which case it will be smaller than the estimated value, or using the brake control value, in which case it will be larger than the estimated value. This allows the vehicle to be controlled more safely.

[0054] As described above, in the vehicle control device 10A of the second embodiment, as in the vehicle control device 10 of the first embodiment, the effect is obtained that even if the calculation load increases, the control value is output according to the situation and autonomous driving is maintained.

[0055] Furthermore, when the calculation time in the autonomous driving control unit 20 does not fall within the calculation cycle time of the control value, the switching unit 22 selects the estimated control value calculated from the control value in the middle of the calculation or the past history value stored in the control history value holding unit 24 and outputs it as an alternative control value. Therefore, the actuator can be controlled with a control value that better matches the state and environmental information of the vehicle, further improving the accuracy and safety of autonomous driving. Third embodimentDevice configuration

[0056] Fig. Fig. 8 is a functional block diagram illustrating a configuration of a vehicle control device 10B according to the third embodiment of the present invention. The difference from the vehicle control device 10A shown in Fig. 5 is that the autonomous driving subsystem control unit 25 is provided, and the same components as those of the vehicle control device 10A described with reference to Fig. 5 are designated by the same reference numerals, and the repeated description is omitted.

[0057] The autonomous driving subsystem control unit 25 is a part that functions as a fallback, allowing operation of an autonomous driving vehicle to continue even if an abnormality such as a malfunction occurs in the autonomous driving control unit 20. It is configured to use algorithms that implement operations that ensure minimum safety with a smaller computational load. Operations that ensure minimum safety include, for example, "stop on the shoulder" and "stop in place," as in the case of emergency stop measures. Operation

[0058] The switching determination by the monitoring unit 21 using the flowchart from Fig. 2, and the calculation process of the control value of the actuator by the autonomous driving control unit 20, which is carried out using the flowchart of Fig. 3 in the description of the vehicle control device 10 of the first embodiment are the same in the vehicle control device 10B of the third embodiment, but the switching process in the switching unit 22 is different from those of the first and second embodiments.

[0059] That is, in the flowchart from Fig. 9, which illustrates the switching process in the switching unit 22, first, step S501 is provided for determining whether or not an abnormality has occurred in the autonomous driving control unit 20. Then, in step S501, if it is determined that an abnormality has occurred in the autonomous driving control unit 20 (NO), the control value of the subsystem calculation result calculated by the autonomous driving subsystem control unit 25 in step S506 is output as an alternative control value, and this is the difference from the first and second embodiments.

[0060] Regarding whether or not an abnormality has occurred in the autonomous driving control unit 20, for example, if a message is periodically communicated with the autonomous driving control unit 20, and if there is no response message from the autonomous driving control unit 20 regarding the message transmitted from the switching unit 22 within a predetermined period of time, then it can be determined that an abnormality has occurred in the autonomous driving control unit 20.

[0061] Again, if it is determined in step S501 that no abnormality has occurred in the autonomous driving control unit 20 (YES), then it is checked in step S502 whether the control value switching request has been transmitted from the monitoring unit 21. If it is confirmed in step S302 that the control value switching request has not been transmitted (NO), the switching unit 22 selects the regular calculation result output from the autonomous driving control unit 20 in step S507.

[0062] Again, if it is confirmed in step S502 that the control value switching request has been transmitted (YES), the switching unit 22 checks the safety determination result notified from the monitoring unit 21 in step S503. In step S503, if safety cannot be ensured (NO), it is determined whether the subsystem calculation result calculated by the autonomous driving subsystem control unit 25 can be output in step S508, and if output is possible (YES), the control value of the subsystem calculation result calculated by the autonomous driving subsystem control unit 25 in step S509 is output as an alternative control value.

[0063] If, on the other hand, outputting the subsystem calculation result in step S508 is not possible, in step S510, the control value for the emergency stop action output from the autonomous driving control unit 20 is selected and output as an alternative control value, and the emergency stop action is executed. Examples of emergency stop actions include "shoulder stop" and "in place stop." The third embodiment differs from the first and second embodiments in that steps S508 and S509 are included.

[0064] When determining whether the subsystem calculation result can be outputted in step S508, a method may be used in which, when the control value changes greatly and the calculation result is such that the vehicle cannot follow it, it is determined that outputting cannot be performed, and when the control value does not change greatly, it is determined that outputting is possible. The change in the control value can be detected by the difference from the previous control value stored in the control history holding unit 24, and if the difference exceeds a predetermined threshold, it is determined that the change in the control value is large.

[0065] In step S503, if the safety determination result shows that safety can be ensured (YES), the switching unit 22 checks whether the intermediate result output rejection information is sent from the autonomous driving control unit 20 (step S504). If it is confirmed in step S504 that intermediate result output rejection information has not been sent (NO), the switching unit 22 selects the control value of the intermediate calculation result and outputs it as an alternative control value in step S511.

[0066] Again, if it is confirmed in step S504 that the intermediate result output rejection information has been sent (YES), then in step S505, the control value calculated from the control history calculated in the control history holding unit 24 is selected and output as an alternative control value, which is different from the vehicle control device 10 of the first embodiment.

[0067] As described above, in the vehicle control device 10B of the third embodiment, as in the vehicle control device 10 of the first embodiment, the effect is obtained that, even when the calculation load increases, the control value is output according to the situation and autonomous driving is maintained. Further, when the calculation time in the autonomous driving control unit 20 does not fall within the calculation cycle time of the control value, the switching unit 22 selects the resultant estimated control value calculated from the control value in the middle of the calculation or the past history value stored in the control history value holding unit 24 and outputs it as an alternative control value.Therefore, the actuator can be controlled with a control value that better matches the vehicle's state and environmental information, further improving the accuracy and safety of autonomous driving.

[0068] Further, when an abnormality has occurred in the autonomous driving control unit 20, the control value of the sub-system calculation result calculated by the autonomous driving sub-system control unit 25 is selected and output as an alternative control value, so that the safety of autonomous driving can be ensured even when an abnormality has occurred in the autonomous driving control unit 20. Hardware configuration

[0069] Each part of the vehicle control devices 10, 10A and 10B of the first to third embodiments described above can be configured using a computer and is implemented by the computer executing the program. That is, the vehicle control devices 10, 10A and 10B are implemented, for example, by a processing circuit 100 included in Fig. 10. A processor such as a central processing unit (CPU) or a digital signal processor (DSP) is used in the processing circuit 100, and the function of each part is implemented by executing the program stored in the storage device.

[0070] Dedicated hardware may be used with processing circuitry 100. When dedicated hardware is used with processing circuitry 100, processing circuitry 100 may be, for example, a single circuit, a composite circuit, a programmed processor, a parallel programmed processor, an application-specific integrated circuit (ASIC), or a field-programmable gate array (FPGA), or a combination thereof.

[0071] It also illustrates Fig.11 illustrates the hardware configuration when the vehicle control devices 10, 10A, and 10B are configured using a processor. In this case, each function of the vehicle control devices 10, 10A, and 10B and the vehicle control device 10 is implemented by software (software, firmware, or a combination of software and firmware) or the like. Software and the like are described as a program and stored in the memory 120.

[0072] A processor 110, which functions as the processing circuit 100, implements the function of each part by reading and executing the program stored in the memory 120 (storage device). That is, it can be said that this program causes the computer to execute the procedure and method of operating the components of the vehicle control devices 10, 10A, and 10B.

[0073] Here, the memory 120 may be, for example, a non-volatile or volatile semiconductor memory such as a random access memory (RAM), a read-only memory (ROM), a flash memory, an erasable programmable read-only memory (EPROM), an electrically erasable programmable read-only memory (EEPROM), or the like, an HDD (Hard Disk Drive), a magnetic disk, a flexible disk, an optical disk, a compact disc, a digital versatile disc (DVD) and a drive therefor, or the like, or any storage medium used in the future.

[0074] The configuration in which the function of each component of the vehicle control devices 10, 10A, and 10B is implemented by either hardware or software is described above. However, the configuration is not limited to this, and a configuration in which some components of the vehicle control devices 10, 10A, and 10B are implemented by dedicated hardware and some other components are implemented by software or the like may also be adopted.

[0075] For example, for some components, the functions are implemented by the processing circuit 100 as dedicated hardware, and for some other components, the functions are implemented by the processing circuit 100, with the processor 110 reading and executing the program stored in the memory 120.

[0076] Accordingly, the vehicle control devices 10, 10A and 10B may implement each of the above functions through hardware, software, firmware, or a combination thereof.

[0077] While the invention has been shown and described in detail, the above description is in all aspects merely illustrative and not restrictive. It should be understood that numerous other modifications not described may be utilized without departing from the scope of the invention.

[0078] In the present invention, the embodiments may be combined, appropriately modified, or features may be omitted without departing from the scope of the invention.

Claims

A vehicle control device comprising:- an autonomous driving control unit (20) configured to determine a travel route when implementing autonomous driving based on environmental information and position information of a vehicle, and to calculate and output a control value according to the travel route;- a monitoring unit (21) configured to monitor the calculation time of the autonomous driving control unit (20); and- a switching unit (22) configured to receive the output from the autonomous driving control unit (20) and output the control value or an alternative control value instead of the control value based on an instruction from the monitoring unit (21), wherein the monitoring unit (21) is configured such that, when the calculation time exceeds a threshold value,the autonomous driving control unit (20) notifies the switching unit (22) of a calculation interruption request, notifies the switching unit (22) of a control value switching request, makes a determination as to whether or not the safety of the vehicle itself is ensured with the alternative control value based on the environmental information and the position information, and notifies the switching unit (22) of the safety determination result, and the switching unit (22) is configured to output the control value or the alternative control value based at least on the control value switching request and the safety determination result, wherein the control value is acquired by obtaining an optimal value by repeating a loop calculation a plurality of times, and if the optimal value is not acquired before the calculation interruption request is transmitted from the monitoring unit (21),the autonomous driving control unit is configured to interrupt the loop calculation by being notified of the calculation interruption request and determine whether a control value in the middle of the calculation can be output as the alternative control value. A vehicle control device according to claim 1, wherein, when it is determined that the control value is not output as the alternative control value in the middle of the calculation, the autonomous driving control unit (20) is configured to notify the switching unit (22) of intermediate result output rejection information and output an emergency stop control value for emergency stopping the vehicle, and when the control value switching request is transmitted and the safety of the vehicle is ensured with the determination result of the safety, the switching unit (22) is configured to output the emergency stop control value as the alternative control value. A vehicle control device according to claim 1, wherein, when it is determined that the control value in the middle of the calculation is output as the alternative control value, the autonomous driving control unit (20) is configured to output the control value in the middle of the calculation, and when the control value switching request is transmitted and the safety of the vehicle is ensured with the determination result of the safety, the switching unit (22) is configured to output the control value in the middle of the calculation as the alternative control value. The vehicle control device according to claim 1, wherein, when it is determined that the control value is not output as the alternative control value in the middle of the calculation, the autonomous driving control unit (20) is configured to notify the switching unit (22) of intermediate result output rejection information, and wherein the switching unit (22) has a previous value holding unit (20) configured to store the previous control value in a previous calculation cycle output from the autonomous driving control unit (20) as a previous value, and when the control value switching request is transmitted and safety is ensured with the determination result of safety, and the intermediate result output rejection information is transmitted from the autonomous driving control unit (20), it is configured to output the previous value,which is stored in the holding unit (23) for the previous value as the alternative control value., The vehicle control device according to claim 1, wherein, when it is determined that the control value in the middle of the calculation is not output as the alternative control value, the autonomous driving control unit (20) is configured to notify the switching unit (22) of intermediate result output rejection information, wherein the switching unit (22) has a control history holding unit (24) configured to store a plurality of control values ​​in a plurality of past calculation cycles output from the autonomous driving control unit (20) as history values, and when the control value switching request is transmitted and the safety of the vehicle is ensured with the determination result of the safety, and the intermediate result output rejection information is notified from the autonomous driving control unit (20),and is configured to output an estimated control value obtained on the basis of the history values ​​stored in the control history value holding unit (24) as the alternative control value., The vehicle control device according to claim 1, further comprising:an autonomous driving subsystem control unit (25) that replaces the autonomous driving control unit (20),wherein the switching unit (22) is configured to determine whether an abnormality occurs in the autonomous driving control unit (20), and when determining that an abnormality occurs, output a control value of a subsystem calculation result calculated by the autonomous driving subsystem control unit (25) as the alternative control value.

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