Autonomous vehicle

Abstract

To provide an automatic driving vehicle which can safely and surely stop when an abnormality exceeding a threshold occurs in a vehicle speed and a steering angle.SOLUTION: An automatic driving vehicle comprises a control monitoring unit 18 which detects an actual value of a drive control result of a travel unit 11, a steering unit 12 and a brake unit 13 and compares target values of various control commands with the drive control result. The control monitoring unit previously includes a model 17a which expresses a travel speed or steering angle as a correction control target corresponding to a property unique to the automatic driving vehicle 10 for the control command about acceleration, deceleration or steering in the normal travel, refers to the model when comparing the target value of the control command with the actual value of the drive control result and compares the correction control target value expected according to the travel condition at this time with the actual value of the drive control result, determines that an error has occurred when the difference has exceeded the threshold, and stops the automatic driving vehicle.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to an autonomous vehicle that monitors controls such as acceleration, deceleration, and steering, and detects abnormalities therein.

Background Art

[0002] Generally, an autonomous vehicle controls the running of the autonomous vehicle based on detection signals from a detection unit including a position sensor, a vehicle speed sensor, a three-axis acceleration sensor, an obstacle sensor, etc. that detect the running state. A main autonomous driving control unit (in this application, the "autonomous driving control unit" is simply referred to as the "control unit", and is used separately from the running control unit, the drive control unit, etc.) generates a running command. Receiving the running command from the control unit, the running control unit generates a running signal, and based on this running signal, the drive control unit drives and controls the running unit, the steering unit, and the braking unit to perform autonomous driving.

[0003] On the other hand, in an autonomous vehicle, it is necessary to detect the occurrence of an abnormality at an early stage in order to prevent an accident or reduce damage no matter what kind of abnormality occurs. For this reason, regarding abnormalities on the output side from the control unit, such as the accelerator, brake, and steering, it is possible to detect the abnormality by adding an error detection function to the device.

Summary of the Invention

Problems to be Solved by the Invention

[0004] However, it is difficult to detect abnormalities in the previous device from these devices such as the accelerator, brake, and steering.

[0005] In view of the above points, the present invention aims to provide an autonomous vehicle that can surely detect the occurrence of an abnormality and stop safely and surely when an abnormality occurs in each device such as the running unit, the steering unit, and the braking unit to be drive-controlled with a simple configuration.

Means for Solving the Problems

[0006] To achieve the above object, the present invention includes a traveling unit, a steering unit, and a braking unit; a drive control unit that drives and controls the traveling unit, the steering unit, and the braking unit; a detection unit including a position sensor, a vehicle speed sensor, a steering angle sensor, a three-axis acceleration sensor, a surrounding sensor, etc. that detect the traveling state; and based on the detection signals from the detection unit te In an autonomous vehicle including a control unit that generates a travel command including target values of various control commands for the traveling unit, the steering unit, and the braking unit, and a travel control unit that generates a travel signal based on the travel command from the control unit and sends it to the drive control unit, further includes a control monitoring unit that detects actual values of the drive control results of the traveling unit, the steering unit, and the braking unit and compares the actual values with the target values of various control commands. The control monitoring unit, regarding control commands related to vehicle speed or steering angle including acceleration and deceleration during normal travel, has in advance a model representing a travel speed or steering angle as a modified control target corresponding to the unique characteristics of the autonomous vehicle Registered in the memory unit , Control that is the control target When comparing the target value of the control command with the actual value of the drive control result, refer to the model, compare the expected modified control target according to the travel conditions at that time with the actual value of the drive control result, and when the difference exceeds the threshold, determine that an error has occurred and send an error occurrence signal to the control unit, When the control unit receives the error occurrence signal, it generates a stop command and sends it to the travel control unit, The travel control unit generates a stop signal based on the stop command, and the drive control unit receives this stop signal and drives and controls the traveling unit, the steering unit, and the braking unit to stop the autonomous vehicle configured as The model takes the control target as the input and the actual value of the drive control result as the output, and for the automatic driving vehicle, obtains the non-linear relational expression of the input and output that measures what vehicle speed or steering angle including acceleration and deceleration can be obtained in the actual environment during normal operation, registers it in the memory unit as a model, and the control monitoring unit reads out the model registered from the memory unit, refers to the model to correct the control target value, and obtains the corrected control target value which is characterized by this.

[0007] The second configuration of the present invention includes a traveling unit, a steering unit, and a braking unit; a drive control unit that drives and controls the traveling unit, the steering unit, and the braking unit; a position sensor, a vehicle speed sensor, a steering angle sensor that detect the traveling state, In an autonomous vehicle comprising a detection unit including a triaxial acceleration sensor, a surrounding sensor, etc., a control unit that generates a driving command including acceleration, deceleration, and steering based on a detection signal from the detection unit, and a driving control unit that generates a driving signal based on the driving command from the control unit and sends it to the driving control unit, further, a control monitoring unit that detects actual values of vehicle speed and steering angle including acceleration and deceleration as driving control results of the traveling unit, the steering unit, and the braking unit, and compares the actual values of the vehicle speed and the steering angle with target values of control commands regarding acceleration, deceleration, and steering. This control monitoring unit has, in advance, a model representing a traveling speed or a steering angle as a corrected control target corresponding to the unique characteristics of the autonomous vehicle for control commands regarding acceleration, deceleration, or steering during normal driving Registered in the memory unit When comparing the target value of the control command Control that is the control target with the actual value of the driving control result, it refers to the model, compares the expected corrected control target value according to the driving conditions at that time with the actual value of the driving control result, determines that an error has occurred when the difference exceeds a threshold value, and sends an error occurrence signal to the control unit. When the control unit receives the error occurrence signal, it generates a stop command and sends it to the driving control unit. The driving control unit generates a stop signal based on the stop command, and the driving control unit drives and controls the traveling unit, the steering unit, and the braking unit upon receiving this stop signal to stop the autonomous vehicle. configured as The model takes the control target as the input and the actual value of the drive control result as the output, and for the automatic driving vehicle, obtains the non-linear relational expression of the input and output that measures what vehicle speed or steering angle including acceleration and deceleration can be obtained in the actual environment during normal operation, registers it in the memory unit as a model, and the control monitoring unit reads out the model registered from the memory unit, refers to the model to correct the control target value, and obtains the corrected control target value It is characterized by this.

[0008] In a third configuration of the present invention, in an autonomous vehicle comprising a traveling unit, a steering unit, and a braking unit, a driving control unit that drives and controls the traveling unit, the steering unit, and the braking unit, a detection unit including a position sensor, a vehicle speed sensor, a steering angle sensor, a triaxial acceleration sensor, a surrounding sensor, etc. that detects the driving state, a control unit that generates a driving command including acceleration, deceleration, and steering based on a detection signal from the detection unit, and a driving control unit that generates a driving signal based on the driving command from the control unit and sends it to the driving control unit, Furthermore, a control monitoring unit is provided that detects the actual value of the vehicle speed as the drive control result of the traveling unit and the braking unit, and compares the target value of the control command regarding acceleration and deceleration with the actual vehicle speed as the drive control result. When it comes to the control commands related to acceleration, deceleration, or steering during normal driving, the control monitoring unit refers to a model representing the traveling speed or the steering angle as the corrected control target corresponding to the specific characteristics of the autonomous vehicle Registered in the memory unit beforehand Control that is the control target and refers to the model when comparing the target value of the control command with the actual value of the drive control result. Then, it compares the expected corrected control target value according to the traveling conditions at that time with the actual value of the drive control result. When the difference exceeds the threshold value, it determines that an error has occurred and sends an error occurrence signal to the control unit. When the control unit receives the error occurrence signal, it generates a stop command and sends it to the traveling control unit. The traveling control unit generates a stop signal based on the stop command, and the drive control unit drives and controls the traveling unit, the steering unit, and the braking unit according to the stop signal to stop the autonomous vehicle configured as The model takes the control target as the input and the actual value of the drive control result as the output, and for the automatic driving vehicle, obtains the non-linear relational expression of the input and output that measures what vehicle speed or steering angle including acceleration and deceleration can be obtained in the actual environment during normal operation, registers it in the memory unit as a model, and the control monitoring unit reads out the model registered from the memory unit, refers to the model to correct the control target value, and obtains the corrected control target value .

[0009] Preferably, the control monitoring unit acquires the actual vehicle speed of the autonomous vehicle through the detection signal from the vehicle speed sensor, or acquires the actual vehicle speed of the autonomous vehicle based on the difference in position during the traveling of the autonomous vehicle according to the detection signal from the position sensor, or acquires the actual vehicle speed of the autonomous vehicle based on the difference in position during the traveling of the autonomous vehicle according to the detection signal from the surrounding sensors.

[0010] Furthermore, in the fourth configuration of the present invention, in an autonomous vehicle including a traveling unit, a steering unit, and a braking unit, a drive control unit that drives and controls the traveling unit, the steering unit, and the braking unit, a detection unit including a position sensor, a vehicle speed sensor, a steering angle sensor, a three-axis acceleration sensor, a surrounding sensor, etc. that detects the traveling state, a control unit that generates a traveling command including steering based on the detection signal from the detection unit, and a traveling control unit that generates a traveling signal based on the traveling command from the control unit and sends it to the drive control unit Furthermore, a control monitoring unit is provided that detects the actual steering angle as the drive control result of the steering unit, and compares the target value of the control command regarding steering with the actual steering angle as the drive control result. When it comes to the control commands regarding acceleration, deceleration, or steering during normal driving, the control monitoring unit Registered in the memory unit previously Control that is the control target has a model representing the traveling speed or the steering angle as a corrected control target corresponding to the specific characteristics of the self-driving vehicle. When comparing the target value of the control command with the actual value of the drive control result, the model is referred to, and the expected corrected control target value according to the traveling conditions at that time is compared with the actual value of the drive control result. When the difference exceeds the threshold value, it is determined that an error has occurred, and an error occurrence signal is sent to the control unit. When the control unit receives the error occurrence signal, a stop command is generated and sent to the travel control unit. The travel control unit generates a stop signal based on the stop command, and the drive control unit drives and controls the travel unit, the steering unit, and the braking unit according to the stop signal to stop the self-driving vehicle. configured as The model takes the control target as the input and the actual value of the drive control result as the output, and for the automatic driving vehicle, obtains the non-linear relational expression of the input and output that measures what vehicle speed or steering angle including acceleration and deceleration can be obtained in the actual environment during normal operation, registers it in the memory unit as a model, and the control monitoring unit reads out the model registered from the memory unit, refers to the model to correct the control target value, and obtains the corrected control target value

[0011] The control monitoring unit may acquire the actual steering angle of the self-driving vehicle based on the detection signal from the steering angle sensor, or may acquire the actual steering angle of the self-driving vehicle based on the difference in the turning angular velocity of the self-driving vehicle from the detection signal of the triaxial acceleration sensor.

Advantages of the Invention

[0012] According to the present invention, it is possible to provide a self-driving vehicle that can surely detect the occurrence of an abnormality when an abnormality occurs in each device such as the travel unit, the steering unit, and the braking unit to be drive-controlled with a simple configuration, and can be safely and surely stopped.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Figure 3

Embodiments for Carrying Out the Invention

[0014] Hereinafter, the present invention will be described in detail based on the embodiments shown in the drawings. FIG. 1 shows the overall configuration of an embodiment of an autonomous vehicle according to the present invention. The autonomous vehicle 10 includes a traveling unit 11 provided at the lower part of a vehicle body (not shown), a steering unit 12, a braking unit 13, a drive control unit 14 that drives and controls the traveling unit 11, the steering unit 12, and the braking unit 13, a traveling control unit 15, a control unit 16, a storage unit 17, a detection unit 20, and other devices (not shown) necessary for traveling, and is configured as a known autonomous vehicle. The autonomous vehicle 10 of the present invention further includes a control monitoring unit 18 to be described later. Each sensor of the drive control unit 14, the traveling control unit 15, the control unit 16, the storage unit 17, the control monitoring unit 18, and the detection unit 20 and the control monitoring unit 18 are mutually connected by a so-called in-vehicle LAN (also called CAN).

[0015] The traveling unit 11 is composed of, for example, four wheels (not shown) and a drive source that drives the front wheels and / or the rear wheels as drive wheels. This drive source has a known configuration and is composed of an engine such as a gasoline engine or a diesel engine, or a drive motor or the like.

[0016] The steering unit 12 has a known configuration. For example, by swinging the front wheels as steering wheels left and right, the autonomous vehicle 10 can move straight, reverse, turn left, or turn right. Note that the drive wheels and the steering wheels may be the same wheels. The braking unit 13 is composed of a known brake structure that stops the rotation of at least only the front wheels, only the rear wheels, or all of the four wheels.

[0017] The drive control unit 14 drives and controls each of the drive source of the traveling unit 11, the steering unit 12, and the braking unit 13. By the drive control of the drive control unit 14, the drive wheels are rotationally driven, the steering wheels are swung left and right, or the braking unit 13 stops the rotation of the wheels, and the autonomous driving vehicle 10 can move forward, backward, or turn left and right to travel or stop in a predetermined direction.

[0018] Based on the travel signal 15a from the travel control unit 15, the drive control unit 14 causes the travel or stop such as vehicle speed, forward movement, backward movement, left and right turning, etc. set by this travel signal 15a to be performed. Further, based on the stop signal 15b from the travel control unit 15, the drive control unit 14 similarly drives and controls the traveling unit 11, the steering unit 12, and the braking unit 13, and quickly decelerates the autonomous driving vehicle 10 and stops it by, for example, pulling it to the road shoulder. The operation of pulling the autonomous driving vehicle 10 to the road shoulder and stopping it is called a fallback operation.

[0019] Based on the travel command 16a output from the control unit 16 described later, the travel control unit 15 generates a travel signal 15a and sends it to the drive control unit 14. At the same time, based on the stop command 16b from the control unit 16, for example, a stop signal 15b for quickly decelerating and pulling to the road shoulder and stopping is generated and sent to the drive control unit 14. The travel signal 15a may include a travel program. Here, the travel signal 15a is created to specify the travel speed, steering angle, acceleration, and deceleration when traveling along the travel route from the departure place to the destination of the autonomous driving vehicle 10. By the drive control unit 14 driving and controlling the traveling unit 11, the steering unit 12, and the braking unit 13 according to the travel signal 15a, the autonomous driving vehicle 10 can travel at the specified travel speed along the travel route from the departure place to the destination.

[0020] The control unit 16 is composed of, for example, a personal computer or the like. It registers various detection signals S1 to S6, which will be described later, input from the detection unit 20 in the storage unit 17, and creates a travel command 16a for traveling along a travel route while referring to these detection signals, and sends the travel signal 15a to the travel control unit 15. The travel command 16a includes various control commands such as travel speed, steering angle, acceleration, and deceleration for the travel unit 11, the steering unit 12, and the braking unit 13. Further, when the control unit 16 receives an error occurrence signal 18a from the control monitoring unit 18, it generates a stop command 16b and sends this stop command 16b to the travel control unit 15.

[0021] The storage unit 17 sequentially stores the travel command 16a input by the control unit 16 or the travel command 16a input from the outside, and the detection signals S1 to S6 from the detection unit 20. Here, the travel command 16a input from the outside is, for example, sent via a network from a management center (not shown) that monitors the autonomous vehicle 10 from the outside. Further, a model 17a, which will be described later, created in advance is registered in the storage unit 17.

[0022] The control monitoring unit 18 detects the actual values of the drive control results of the travel unit 11, the steering unit 12, and the braking unit 13, compares these actual values with the corrected control target values of various control commands, and when the set threshold value is exceeded, determines that an error has occurred in the operations of the travel unit 11 and the braking unit 13 or the steering unit 12, generates an error occurrence signal 18a, and has a function of sending this error occurrence signal 18a to the control unit 16. The actual values of the drive control results are, for example, the vehicle speed and the steering angle, and are input to the control monitoring unit 18 via the control unit 16 by the detection signals S3 and S6 from the vehicle speed sensor 23 and the steering angle sensor 26 of the detection unit 20. The corrected control target values according to the travel command 16a input to the control monitoring unit 18 are obtained by correcting the target values of the vehicle speed and the steering angle according to the control commands regarding the vehicle speed and the steering angle including acceleration and deceleration by the model 17a, which will be described later.

[0023] Here, for the control targets of the control commands included in the driving command 16a, such as various control commands like driving speed, steering angle, acceleration, deceleration, etc., the actual values as the actual driving control results in the autonomous vehicle 10 vary depending on the characteristics specific to the autonomous vehicle 10, such as the total vehicle weight, electrical system, drive source, hydraulic system, and tires, etc., or the road surface conditions of the driving route, and furthermore, various conditions such as the output of the non-linear assist force of the power steering and the torque of the steering motor. Therefore, regarding the autonomous vehicle 10, taking the control target as the input and the actual value as the output which is the driving control result, a non-linear relational expression of the input-output that measures what vehicle speed or steering angle including what acceleration and deceleration can be obtained in the actual environment during normal operation regarding the autonomous vehicle 10 is obtained and registered in the storage unit 17 as the model 17a. The control monitoring unit 18 reads out the model 17a from the storage unit 17 and obtains a corrected control target value by referring to the model 17a to correct the control target value. Thereby, when comparing the control target and the actual value, the control monitoring unit 18 reads out the model 17a from the storage unit 17, corrects the control target value by referring to the model 17a, and compares the corrected control target value actually realized by the autonomous vehicle 10 with the actual value which is the driving control result. Thereby, the accuracy can be improved compared to comparing the control target value and the actual value.

[0024] When the difference D1 between the actual value of the vehicle speed and the target value corrected by the model and the difference D2 between the actual value of the steering angle and the target value corrected by the model are respectively below the previously set threshold values D1' and D2', the control monitoring unit 18 determines that the operations of the traveling unit 11, the steering unit 12, and the braking unit 13 are normal. On the other hand, when at least one of the two differences, D1 or D2, exceeds the corresponding threshold value D1' or D2', the control monitoring unit 18 determines that an error has occurred in the operations of the traveling unit 11 and the braking unit 13 or the steering unit 12, generates an error occurrence signal 18a, and sends this error occurrence signal 18a to the control unit 16. Here, during the automatic driving of the autonomous vehicle 10, the control monitoring unit 18 monitors the difference between the actual value and the target value corrected by the model every predetermined time T. The predetermined time T is, for example, several ms to 20 mS.

[0025] In the illustrated case, the detection unit 20 is composed of a sign sensor 21, a position sensor 22, a vehicle speed sensor 23, a three-axis acceleration sensor 24, a surrounding sensor 25, and a steering angle sensor 26.

[0026] The sign sensor 21 is, for example, a monocular camera provided at the upper part of the windshield, captures an image of the front in the traveling direction of the autonomous vehicle 10, and sends the captured image signal to the control unit 16 as a detection signal S1. Based on the detection signal S1, the control unit 16 recognizes, by image recognition, the situation in front of the autonomous vehicle 10, particularly the white lines and guardrails indicating both sides of the front traveling road, grasps the current position within the traveling road, compares it with the map data of the previously set traveling route, performs self-position estimation, corrects the traveling command 16a so as to maintain the route within the traveling road, and sends it to the traveling control unit 15. Note that the sign sensor 21 is not limited to a monocular camera, and a binocular camera, a stereo camera, etc. may also be used.

[0027] The position sensor 22 detects the longitude and latitude by a GNSS sensor, for example, a GPS sensor. Thereby, the position sensor 22 detects the geodesic data of the autonomous vehicle 10 at that time, for example, every predetermined time, and sends it to the control unit 16 as a detection signal S2. The control unit 16 compares the detection signal S2 with the map data of the traveling road read from the storage unit 17, obtains the traveling position of the autonomous vehicle 10 within the traveling road, corrects the traveling command 16a so as to maintain the route within the traveling road, and sends it to the traveling control unit 15.

[0028] The vehicle speed sensor 23 detects, for example, the rotational speed of the wheels of the traveling unit 11 and sends the detected rotational speed as a detection signal S3 to the control unit 16. The triaxial acceleration sensor 24 is a so-called gyro, which detects the three-dimensional attitude of the autonomous driving vehicle 10 based on the acceleration in the three axial directions of the vehicle body and sends the detection signal S4 to the control unit 16.

[0029] The surrounding sensor 25 is composed of, for example, a plurality of lidars provided near the bumpers at the front and rear of the vehicle body. A lidar (Light Detection and Ranging) is also called a laser radar, which performs light detection and ranging or laser imaging detection and ranging. As the lidar, a two-dimensional lidar or a three-dimensional lidar may be used. The three-dimensional lidar can perform laser imaging detection on the curved road 11c and measure the distance to the detected object. Note that the surrounding sensor 25 may include, instead of or in addition to the lidar, for example, a stereo camera attached to the front, rear, left, and right of the vehicle body or a lidar attached to the roof of the vehicle body. As a camera other than the stereo camera, a monocular camera or a binocular camera can be used.

[0030] The surrounding sensor 25 can detect the objects on the traveling path around the autonomous driving vehicle 10, that is, obstacles and other vehicles in the front, rear, left, and right. When detecting an object on the traveling path, a detection signal S5 including the direction and distance of the object is sent to the travel control unit 15.

[0031] The steering angle sensor 26 detects the steering angle of the autonomous driving vehicle 10, for example, directly from the steering wheel of the traveling unit 11 or indirectly from the rotation angle of the steering, and sends the steering angle as a detection signal S6 to the control unit 16.

[0032] Based on the detection signals S1 to S6 from the identification sensor 21, position sensor 22, vehicle speed sensor 23, three-axis acceleration sensor 24, surrounding sensor 25, and steering angle sensor 26 of the detection unit 20, the control unit 16 grasps the driving state such as the driving position, driving speed, attitude, objects in the front area, for example, the position and distance of objects such as obstacles and other driving vehicles, and the steering angle of the autonomous driving vehicle 10 to estimate its own position, and determines the progress of the driving signal driving program 15a at that time.

[0033] Here, the comparison between the control command included in the driving command 16a by the control monitoring unit 18 and the drive control result is performed as follows. FIG. 2 shows the case of control monitoring regarding the driving speed. The driving control unit 15 generates a driving signal 15a based on the driving command 16a from the control unit 16, and controls the drive control unit 14 with this driving signal 15a to drive and control the driving unit 11, steering unit 12, and braking unit 13. Then, the control monitoring unit 18 directly obtains the vehicle speed of the autonomous driving vehicle 10 as the drive control result of the driving unit 11, steering unit 12, and braking unit 13 from the detection signal S3 of the vehicle speed sensor 23 of the detection unit 20.

[0034] On the other hand, the control command regarding the vehicle speed of the driving command 16a input from the control unit 16 to the control monitoring unit 18, that is, the control target, is corrected corresponding to various characteristics of the autonomous driving vehicle 10 via the model 17a, and is sent to the control monitoring unit 18 as the corrected control target of the vehicle speed.

[0035] The control monitoring unit 18 compares the actual driving speed based on the detection signal S3 of the vehicle speed sensor 23 of the detection unit 20 with the corrected control target of the vehicle speed described above, and determines whether the operations of the driving unit 11 and the braking unit 13 are normal.

[0036] When the difference between the actual driving speed and the corrected control target of the vehicle speed is equal to or less than a preset threshold value D1', the control monitoring unit 18 determines that the operations of the driving unit 11 and the braking unit 13 are normal. On the contrary, when the difference between the actual driving speed and the corrected control target of the vehicle speed exceeds the preset threshold value D1', the control monitoring unit 18 determines that an error has occurred in the operations of the driving unit 11 and the braking unit 13, generates an error occurrence signal 18a, and sends it to the control unit 16.

[0037] According to the automatic driving vehicle 10 of the present invention, the control monitoring unit 18 detects the actual drive control result based on the detection signal from the detection unit 20, and compares this drive control result with various control commands included in the travel command 16a, that is, the control target. When the traveling unit 11, the steering unit 12, and the braking unit 13 are operating normally, since the difference between the control target and the actual control result does not exceed a predetermined threshold value, the control monitoring unit 18 does not send the error occurrence signal 18a to the control unit 16 assuming that the operations of the traveling unit 11, the steering unit 12, and the braking unit 13 are normal. Therefore, the control unit 16 continues the automatic driving of the automatic driving vehicle 10.

[0038] On the other hand, when an abnormality occurs in the traveling unit 11, the steering unit 12, and the braking unit 13, for example, when the traveling speed cannot be adjusted to the target value by acceleration or deceleration, or when the steering angle cannot be adjusted to the target value by steering, the control monitoring unit 18 determines that an error has occurred because the difference between the control target and the actual control result exceeds a predetermined threshold value, generates an error occurrence signal 18a, and sends it to the control unit 16. In response to this, the control unit 16 generates a stop command 16b and sends it to the travel control unit 15, and the travel control unit 15 generates a stop signal 15b, and the drive control unit 14 drives and controls the traveling unit 11, the steering unit 12, and the braking unit 13 to stop the automatic driving vehicle 10. Therefore, even if an abnormality occurs in the operations of the traveling unit 11, the steering unit 12, and the braking unit 13, the control monitoring unit 18 compares various control commands included in the travel command 16a with the drive control result detected by the control monitoring unit 18, and when the difference exceeds the threshold value, the control unit 16 stops the automatic driving vehicle 10, so that the automatic driving vehicle 10 stops safely and surely without running wild or going off the road. In this way, in the control monitoring unit 18, without directly monitoring the operations of the traveling unit 11, the steering unit 12, and the braking unit 13, it is possible to detect the occurrence of an error by comparing the corrected control target value corrected by the model 17a with respect to the control target and the drive control result detected by the detection unit 20.

[0039] The automated vehicle 10 according to the embodiment of the present invention is configured as described above and operates as follows. In the flowchart of FIG. 3, first, in step ST1, a travel command 16a as a travel program is created by the control unit 16 before travel, or a travel command 16a is input to the control unit 16 from the outside and stored in the storage unit 17. At the start of travel in step ST2, the control unit 16 of the automated vehicle 10 reads the travel command 16a from the storage unit 17 and sends it to the travel control unit 15. The travel control unit 15 generates a travel signal 15a based on the travel command 16a, controls the drive control unit 14, and drives and controls the travel unit 11, the steering unit 12, and the braking unit 13. As a result, in step ST3, the drive control unit 14 drives and controls the travel unit 11, the steering unit 12, and the braking unit 13 according to the travel signal 15a, so that the automated vehicle 10 performs automatic travel according to the travel signal 15a.

[0040] In step ST4, a detection signal S3 from the vehicle speed sensor 23 of the detection unit 20 is input to the control monitoring unit 18 as the actual value of the vehicle speed, and in step ST5, a detection signal S6 from the steering angle sensor 26 of the detection unit 20 is input to the control monitoring unit 18 as the actual value of the steering angle. On the other hand, in step ST6, the travel command 16a is input from the control unit 16 to the model 17a. In step ST7, the control command regarding the vehicle speed included in the travel command 16a is corrected through the model 17a and input to the control monitoring unit 18 as the corrected control target for the vehicle speed. Further, in step ST8, the control command regarding the steering included in the travel command 16a is corrected through the model 17a and input to the control monitoring unit 18 as the corrected control target for the steering angle.

[0041] As a result, in step ST9, the control monitoring unit 18 compares the actual value of the vehicle speed with the target value, which is the corrected control target, that is, compares the difference D1 with the threshold value D1'. When the difference D1 > D1', the control monitoring unit 18 determines that an error has occurred in the operations of the traveling unit 11 and the braking unit 13 in step ST10, generates an error occurrence signal 18a, and sends it to the control unit 16. In response to this, the control unit 16 generates a stop command 16b instead of the traveling command 16a in step ST11 and sends it to the travel control unit 15. As a result, the travel control unit 15 generates a stop signal 15b instead of the travel signal 15a in step ST12 and sends it to the drive control unit 14. Therefore, the drive control unit 14 drives and controls the traveling unit 11, the steering unit 12, and the braking unit 13 based on this stop signal 15b in step ST13, and stops the autonomous driving vehicle 10, thereby ending the autonomous driving.

[0042] On the other hand, in step ST9, when the difference D1 ≤ D1', the control monitoring unit 18 does not generate the error occurrence signal 18a, and the control unit 16 continues the autonomous driving of the autonomous driving vehicle 10 as it is. Subsequently, the control monitoring unit 18 compares the actual value of the steering angle with the target value, which is the corrected control target, in step ST14, that is, compares the difference D2 with the threshold value D2'. When the difference D2 > D2', the control monitoring unit 18 determines that an error has occurred in the operation of the steering unit 12 in step ST15, generates an error occurrence signal 18a, and sends it to the control unit 16.

[0043] In response to this, the control unit 16 proceeds to step ST11, similarly generates a stop command 16b instead of the traveling command 16a, and sends it to the travel control unit 15. As a result, the travel control unit 15 generates a stop signal 15b instead of the travel signal 15a in step ST12 and sends it to the drive control unit 14. Therefore, the drive control unit 14 drives and controls the traveling unit 11, the steering unit 12, and the braking unit 13 based on this stop signal 15b in step ST13, and stops the autonomous driving vehicle 10, thereby ending the autonomous driving.

[0044] On the other hand, when the difference D2 ≤ D2', in step ST14, the control monitoring unit 18 does not generate the error occurrence signal 18a, and the control unit 16 continues the autonomous driving of the autonomous driving vehicle 10 as it is. Then, after the elapse of a predetermined time T in step ST16, it returns to step ST4 and repeats steps ST4 to ST15 at predetermined time intervals. Thus, the control monitoring in the autonomous vehicle 10 of the present embodiment is completed.

[0045] When detecting the traveling speed and the steering angle as shown in FIG. 3, according to the autonomous vehicle 10 of the present invention, the control monitoring unit 18 detects the traveling speed and the steering angle, which are the actual drive control results, based on the detection signals from the detection unit 20, and can compare this drive control result with the control commands regarding acceleration, deceleration, and steering included in the driving command 16a, that is, the target speed and the target steering angle which are the control targets. When the traveling unit 11, the steering unit 12, and the braking unit 13 are operating normally, since the difference between the control target and the actual control result does not exceed a predetermined threshold value, the control monitoring unit 18 determines that the operations of the traveling unit 11, the steering unit 12, and the braking unit 13 are normal, and does not send the error occurrence signal 18a to the control unit 16. Accordingly, the control unit 16 continues the autonomous driving of the autonomous vehicle 10.

[0046] On the other hand, when an abnormality occurs in the traveling unit 11, the steering unit 12, and the braking unit 13, and the traveling speed cannot be adjusted to the target speed by acceleration or deceleration, or the steering angle cannot be adjusted to the target steering angle by steering, the control monitoring unit 18 determines that an error has occurred because the difference between the control target and the actual control result exceeds a predetermined threshold value, generates the error occurrence signal 18a, and sends it to the control unit 16. In response to this, the control unit 16 generates a stop command 16b and sends it to the travel control unit 15, and the travel control unit 15 generates a stop signal 15b and drives and controls the traveling unit 11, the steering unit 12, and the braking unit 13 by the drive control unit 14 to stop the autonomous vehicle 10. Accordingly, even if an abnormality occurs in the operations of the traveling unit 11, the steering unit 12, and the braking unit 13, the control monitoring unit 18 compares the control commands regarding acceleration, deceleration, and steering included in the driving command 16a with the traveling speed and the steering angle as the drive control results detected by the control monitoring unit 18, and stops the autonomous vehicle 10 when the difference exceeds the threshold value, so that the autonomous vehicle 10 does not run wild or deviate from the road, and stops safely and surely.

[0047] In the above-described embodiment, the control monitoring unit 18 monitors the operations of the vehicle speed and the steering angle. However, the present invention is not limited to this, and the control monitoring unit 18 may monitor only the vehicle speed or only the operation of the steering angle.

[0048] (When detecting the vehicle speed) When detecting the traveling speed, the control monitoring unit 18 detects the traveling speed, which is the actual drive control result, based on the detection signal from the detection unit 20, and compares this drive control result with the control commands regarding acceleration and deceleration included in the travel command 16a, that is, the target speed which is the control target. When the traveling unit 11 and the braking unit 13 are operating normally, since the difference between the control target and the actual control result does not exceed a predetermined threshold value, the control monitoring unit 18 determines that the operations of the traveling unit 11 and the braking unit 13 are normal and does not send the error occurrence signal 18a to the control unit 16. Therefore, the control unit 16 continues the automatic driving of the autonomous vehicle 10.

[0049] On the other hand, when an abnormality occurs in the traveling unit 11 and the braking unit 13 and the traveling speed cannot be adjusted to the target speed by acceleration or deceleration, the difference between the control target and the actual control result exceeds a predetermined threshold value, so the control monitoring unit 18 determines that an error has occurred, generates the error occurrence signal 18a, and sends it to the control unit 16. In response to this, the control unit 16 generates a stop command 16b and sends it to the travel control unit 15. The travel control unit 15 generates a stop signal 15b and drives and controls the traveling unit 11, the steering unit 12, and the braking unit 13 by the drive control unit 14 to stop the autonomous vehicle 10. Therefore, even if an abnormality occurs in the operations of the traveling unit 11 and the braking unit 13, the control command regarding acceleration and deceleration included in the travel command 16a is compared with the traveling speed as the drive control result detected by the control monitoring unit 18 by the control monitoring unit 18, and when the difference exceeds the threshold value, the control unit 16 stops the autonomous vehicle 10, so that the autonomous vehicle 10 does not run wild and stops safely and surely.

[0050] (When detecting the steering angle) When detecting the steering angle, the control monitoring unit 18 detects the steering angle which is the actual drive control result based on the detection signal from the detection unit 20, and compares this drive control result with the steering-related command included in the driving command 16a, that is, the target steering angle which is the control target. When the steering unit 12 is operating normally, since the difference between the control target and the actual control result does not exceed a predetermined threshold value, the control monitoring unit 18 determines that the operation of the steering unit 12 is normal and does not send the error occurrence signal 18a to the control unit 16. Therefore, the control unit 16 continues the automatic driving of the autonomous vehicle 10.

[0051] On the other hand, when an abnormality occurs in the steering unit 12 and the steering angle cannot be adjusted to the target steering angle by steering, the difference between the control target and the actual control result exceeds a predetermined threshold value, so the control monitoring unit 18 determines that an error has occurred, generates the error occurrence signal 18a, and sends it to the control unit 16. In response to this, the control unit 16 generates a stop command 16b and sends it to the driving control unit 15, and the driving control unit 15 generates a stop signal 15b, and the driving control unit 14 drives and controls the running unit 11, the steering unit 12, and the braking unit 13 to stop the autonomous vehicle 10. Therefore, even if an abnormality occurs in the operation of the steering unit 12, the control monitoring unit 18 compares the steering-related control command included in the driving command 16a with the steering angle as the drive control result detected by the control monitoring unit 18, and when the difference exceeds the threshold value, the control unit 16 stops the autonomous vehicle 10, so that the autonomous vehicle 10 stops safely and surely without running off the road.

[0052] According to the autonomous vehicle 10 of the present invention, the control monitoring unit 18 previously has a model 17a representing the running speed or the steering angle as a corrected control target corresponding to the unique characteristics of the autonomous vehicle 10 with respect to the control commands related to acceleration, deceleration, or steering included in the driving command 16a during normal running. When the control unit 16 compares the control command and the drive control result, it refers to the model 17a and compares the expected corrected control target according to the running conditions at that time with the drive control result to determine whether an error has occurred.

[0053] According to the above configuration, the model 17a is set in advance as a so-called input-output non-linear relational expression that measures various control commands included in the driving command 16a, such as control commands related to acceleration, deceleration, or steering, for example, the target speed and target steering angle that are control targets, and what driving speed or steering angle can be obtained in the actual environment of the autonomous vehicle 10 corresponding to these control targets. Thereby, during the autonomous driving of the autonomous vehicle 10, the control monitoring unit 18 refers to the model 17a from the control command, calculates a corrected control target expected according to the driving conditions at that time, compares this corrected control target with the drive control result, and determines the occurrence of an error, so that the occurrence of an error can be detected quickly and accurately.

[0054] The present invention can be implemented in various forms without departing from the spirit thereof. For example, in the above-described embodiment, when the control monitoring unit 18 detects the occurrence of an error, the control unit 16 generates a stop command 16b for a retreat operation that causes the autonomous vehicle 10 to quickly decelerate and stop by pulling over to the road shoulder, but it may also be stopped immediately on the spot.

[0055] In the above-described embodiment, the control monitoring unit 18 directly obtains the actual value of the vehicle speed based on the detection signal S3 from the vehicle speed sensor 23 of the detection unit 20 provided in the autonomous vehicle 10. However, it is not limited to this, and based on the detection signals S2 and S5 from the position sensor 22 or the surrounding sensor 25, the vehicle speed of the autonomous vehicle 10 is calculated by taking the distance, which is the amount of change in position accompanying the driving of the autonomous vehicle 10, as the difference in position, and the actual value of the vehicle speed may be obtained indirectly.

[0056] According to these configurations, the control monitoring unit 18 can monitor the vehicle speed, which is the drive control result, by directly obtaining the actual vehicle speed from the detection signal from the vehicle speed sensor 23 or indirectly based on the detection signals from the position sensor 22 and the surrounding sensor 25.

[0057] In the above-described embodiment, the control monitoring unit 18 directly acquires the actual vehicle speed based on the detection signal S6 from the steering angle sensor 26 of the detection unit 20 provided in the autonomous vehicle 10. However, the present invention is not limited to this. Based on the detection signal S4 from the triaxial acceleration sensor 24, an angle that is the amount of change in the turning angular velocity accompanying the running of the autonomous vehicle 10 is used as the difference in the steering angle, and the steering angle of the autonomous vehicle 10 is calculated, and it is obvious that the actual value of the steering angle may be indirectly acquired.

[0058] According to these configurations, the control monitoring unit 18 can monitor the steering angle, which is the drive control result, by directly acquiring the steering angle from the steering angle sensor 26 or indirectly acquiring the steering angle based on the detection signal from the triaxial acceleration sensor 24.

Explanation of Reference Numerals

[0059] 10 Autonomous vehicle 11 Traveling unit 12 Steering unit 13 Braking unit 14 Drive control unit 15 Travel control unit 15a Travel signal 15b Stop signal 16 Control unit 16a Travel command 16b Stop command 17 Storage unit 17a Model 18 Control monitoring unit 18a Error occurrence signal 20 Detection unit 21 Sign sensor 22 Position sensor 23 Vehicle speed sensor 24 Triaxial acceleration sensor 25 Surrounding sensor 26 Steering angle sensor S1~S7 Detection signals

Claims

1. In an autonomous vehicle comprising a running unit, a steering unit, and a braking unit; a drive control unit for driving and controlling the running unit, the steering unit, and the braking unit; a detection unit including a position sensor, a vehicle speed sensor, a steering angle sensor, a three-axis acceleration sensor, a surrounding sensor, etc. for detecting the running state; a control unit for generating a running command including target values of various control commands to the running unit, the steering unit, and the braking unit based on detection signals from the detection unit; and a running control unit for generating a running signal based on the running command from the control unit and sending it to the drive control unit, further comprising a control monitoring unit for detecting actual values of the drive control results of the running unit, the steering unit, and the braking unit and comparing the actual values with the target values of the various control commands, wherein the control monitoring unit registers in advance in a storage unit a model representing a running speed or a steering angle as a modified control target corresponding to the unique characteristics of the autonomous vehicle with respect to control commands regarding vehicle speed or steering angle including acceleration and deceleration during normal running, when comparing the control target value of the control command with the actual value of the drive control result, referring to the model and comparing the expected modified control target value according to the running conditions at that time with the actual value of the drive control result, and determining that an error has occurred when the difference exceeds a threshold value and sending an error occurrence signal to the control unit, the control unit generates a stop command when receiving the error occurrence signal and sends it to the running control unit, the running control unit generates a stop signal based on the stop command, and the drive control unit drives and controls the running unit, the steering unit, and the braking unit with the stop signal to stop the autonomous vehicle, the model obtains a non-linear input-output relational expression that measures what vehicle speed or steering angle including acceleration and deceleration can be obtained in an actual environment during normal operation for the autonomous vehicle, with the control target as the input and the actual value of the drive control result as the output, and registers it in the storage unit as the model, an autonomous vehicle, wherein the control monitoring unit reads the registered model from the storage unit, refers to the model to correct the control target value, and obtains the corrected control target value.

2. A running gear, a steering unit, and a braking unit, a drive control unit for driving and controlling the running gear, the steering unit, and the braking unit, a detection unit including a position sensor, a vehicle speed sensor, a steering angle sensor, a three-axis acceleration sensor, a surrounding sensor, etc. for detecting a running state, a control unit for generating a running command including acceleration, deceleration, and steering based on a detection signal from the detection unit, and a running control unit for generating a running signal based on the running command from the control unit and sending it to the drive control unit, in an autonomous vehicle equipped with: Furthermore, an actual value of vehicle speed and steering angle including acceleration and deceleration as a drive control result of the running gear, the steering unit, and the braking unit is detected, and a control monitoring unit for comparing the actual value of the vehicle speed and the steering angle with a target value of a control command regarding acceleration, deceleration, and steering is provided. The control monitoring unit has previously registered in a storage unit a model representing a running speed or a steering angle as a modified control target corresponding to the unique characteristics of the autonomous vehicle for a control command regarding acceleration, deceleration, or steering during normal running. When comparing the control target value of the control command with the actual value of the drive control result, the model is referred to, the expected modified control target value according to the running conditions at that time is compared with the actual value of the drive control result, and when the difference exceeds a threshold value, it is determined that an error has occurred and an error occurrence signal is sent to the control unit. When the control unit receives the error occurrence signal, it generates a stop command and sends it to the running control unit. The running control unit generates a stop signal based on the stop command, and the drive control unit is configured to drive and control the running gear, the steering unit, and the braking unit with the stop signal to stop the autonomous vehicle. The model obtains a non-linear input-output relational expression that measures what vehicle speed or steering angle including acceleration and deceleration can be obtained in an actual environment during normal operation for the autonomous vehicle, with the control target as the input and the actual value of the drive control result as the output, and is registered in the storage unit as the model. An autonomous vehicle in which the control monitoring unit reads the registered model from the storage unit, refers to the model to correct the control target value, and obtains the modified control target value.

3. In an autonomous vehicle comprising a running unit, a steering unit, and a braking unit; a drive control unit that drives and controls the running unit, the steering unit, and the braking unit; a detection unit including a position sensor, a vehicle speed sensor, a steering angle sensor, a three-axis acceleration sensor, a surrounding sensor, etc. that detects the running state; a control unit that generates a running command including acceleration, deceleration, and steering based on a detection signal from the detection unit; and a running control unit that generates a running signal based on the running command from the control unit and sends it to the drive control unit, further comprising a control monitoring unit that detects an actual value of the vehicle speed as a drive control result of the running unit and the braking unit, and compares a target value of a control command regarding the acceleration and deceleration with the actual vehicle speed as the drive control result, the control monitoring unit has previously registered in a storage unit a model representing a running speed or a steering angle as a modified control target corresponding to the unique characteristics of the autonomous vehicle for a control command regarding acceleration, deceleration, or steering during normal running, when comparing the control target value that is the control target of the control command with the actual value of the drive control result, referring to the model, comparing the expected modified control target value according to the running conditions at that time with the actual value of the drive control result, and determining that an error has occurred when the difference exceeds a threshold value and sending an error occurrence signal to the control unit, when the control unit receives the error occurrence signal, generating a stop command and sending it to the running control unit, the running control unit is configured to generate a stop signal based on the stop command, and the drive control unit drives and controls the running unit, the steering unit, and the braking unit with the stop signal to stop the autonomous vehicle, the model obtains a non-linear relational expression of input and output that measures what vehicle speed or steering angle including acceleration and deceleration can be obtained in an actual environment during normal operation for the autonomous vehicle, with the control target as the input and the actual value of the drive control result as the output, and is registered in the storage unit as the model, an autonomous vehicle in which the control monitoring unit reads the registered model from the storage unit, refers to the model to correct the control target value, and obtains the modified control target value.

4. The autonomous vehicle according to claim 2 or 3, wherein the control monitoring unit obtains the actual vehicle speed of the autonomous vehicle based on a detection signal from a vehicle speed sensor.

5. The automatic driving vehicle according to claim 2 or 3, wherein the control and monitoring unit obtains the actual vehicle speed of the automatic driving vehicle based on the difference in position accompanying the running of the automatic driving vehicle from the detection signal of the position sensor.

6. The automatic driving vehicle according to claim 2 or 3, wherein the control and monitoring unit obtains the actual vehicle speed of the automatic driving vehicle based on the difference in position accompanying the running of the automatic driving vehicle from the detection signal of the surrounding sensor.

7. In an automatic driving vehicle including a traveling unit, a steering unit, and a braking unit; a drive control unit that drives and controls the traveling unit, the steering unit, and the braking unit; a detection unit including a position sensor, a vehicle speed sensor, a steering angle sensor, a triaxial acceleration sensor, a surrounding sensor, etc. that detect the traveling state; a control unit that generates a traveling command including steering based on the detection signal from the detection unit; and a traveling control unit that generates a traveling signal based on the traveling command from the control unit and sends it to the drive control unit, further comprising a control and monitoring unit that detects the actual steering angle as the drive control result of the steering unit, and compares the target value of the control command regarding the steering with the actual steering angle as the drive control result. The control and monitoring unit registers in advance in the storage unit a model representing a traveling speed or a steering angle as a corrected control target corresponding to the inherent characteristics of the automatic driving vehicle for control commands related to acceleration, deceleration, or steering during normal traveling. When comparing the control target value that is the control target of the control command with the actual value of the drive control result, the model is referred to, and the expected corrected control target value corresponding to the traveling conditions at that time is compared with the actual value of the drive control result. When the difference exceeds the threshold value, it is determined that an error has occurred, and an error occurrence signal is sent to the control unit. When the control unit receives the error occurrence signal, it generates a stop command and sends it to the traveling control unit. The traveling control unit generates a stop signal based on the stop command, and the drive control unit drives and controls the traveling unit, the steering unit, and the braking unit with the stop signal to stop the automatic driving vehicle. The model is obtained by obtaining a non-linear relational expression of input and output that measures what vehicle speed or steering angle including acceleration and deceleration can be obtained in the actual environment during normal operation for the automatic driving vehicle, with the control target as the input and the actual value of the drive control result as the output, and is registered in the storage unit as the model. An automated vehicle in which the control and monitoring unit reads out the registered model from the storage unit, refers to the model, corrects the control target value, and obtains the corrected control target value. **Claim 8** The automated vehicle according to claim 2 or 7, wherein the control and monitoring unit obtains the actual steering angle of the automated vehicle based on a detection signal from a steering angle sensor. **Claim 9** The automated vehicle according to claim 2 or 7, wherein the control and monitoring unit obtains the actual steering angle of the automated vehicle based on the difference in the turning angular velocity of the automated vehicle based on a detection signal from a triaxial acceleration sensor.

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