Driving control device, driving control method, and program
Patent Information
- Application Number
- JP2024010388
- Authority / Receiving Office
- JP · JP
- Patent Type
- Patents
- Current Assignee / Owner
- Filing Date
- 2024-01-26
- Publication Date
- 2025-09-24
- Estimated Expiration
- 2044-01-26
Abstract
Description
[Technical Field]
[0001] The present invention relates to a cruise control device, a cruise control method, and a program for controlling the cruise of a vehicle so that the vehicle follows a target trajectory. [Background technology]
[0002] In recent years, efforts to provide access to sustainable transportation systems that take into consideration vulnerable traffic participants have become more active. To achieve this, we are focusing on research and development into driver assistance technologies to further improve road safety and convenience. One type of driver assistance technology known as lane keeping assist is one that assists the driver in steering the vehicle to keep it in the center of the lane.
[0003] For example, Patent Document 1 describes a vehicle steering assist device that executes steering assist control so that the vehicle travels along a target driving line. In particular, Patent Document 1 describes that during a cant switching period immediately after it is determined that the road surface has switched from a non-canted road surface to a canted road surface, the control gain of the integral control term, which is set by integrating the lateral deviation of the vehicle, is set to a value higher than a normal value.
[0004] Furthermore, Patent Document 2 describes a vehicle control device that controls the steering of a vehicle so that the vehicle travels along a target travel path for changing lanes. In particular, Patent Document 2 describes that the vehicle control device corrects a target steering angle based on a vehicle lane gradient that indicates the gradient of the road surface in the width direction of the vehicle lane and an adjacent lane gradient that indicates the gradient of the road surface in the width direction of the adjacent lane into which the vehicle will change lanes, and performs steering control so that the vehicle follows the corrected target steering angle. [Prior art documents] [Patent documents]
[0005] [Patent Document 1] Patent No. 7028115 [Patent Document 2] International Publication No. 2022 / 259552 Summary of the Invention [Problem to be solved by the invention]
[0006] If the cant angle of the road surface changes suddenly, for example, if the inclination direction of the road surface changes suddenly from right to left or from left to right, the cant may cause the steering to remain in the direction in which the vehicle is moving, and the vehicle may deviate from the target trajectory.
[0007] In Patent Document 1, the timing for setting the control gain of the integral control term to a value higher than the normal value is immediately after it is determined that the road surface has switched from a non-cant road surface to a cant road surface, so there remains a risk of the vehicle deviating if the direction of the cant slope changes suddenly. In Patent Document 2, the target steering angle is corrected based on road surface gradient information obtained in advance from a map database, so it does not address sudden changes in the direction of the cant slope. There is room for improvement in suppressing vehicle deviation from the target trajectory in the event of such a sudden change in the cant angle.
[0008] The present invention provides a cruise control device, a cruise control method, and a program that can suppress deviation of a vehicle from a target trajectory due to cant of a road surface when the cant angle of the road surface changes suddenly, thereby contributing to the development of a sustainable transportation system. [Means for solving the problem]
[0009] The present invention provides A driving control device that controls driving of a vehicle so as to follow a target trajectory, a cant acquisition unit that acquires a cant angle that indicates a lateral inclination degree of a road surface on which the vehicle is traveling; a deviation calculation unit that calculates a lateral deviation between the position of the target trajectory and the position of the vehicle in the lateral direction; a control unit that calculates a target steering angle of the vehicle based on the cant angle and the lateral deviation, and controls steering of the vehicle to follow the target steering angle, The feedback term of the target steering angle calculated based on the cant angle and the lateral deviation is provided with a limit that is set variably according to the cant angle.
[0010] The present invention also provides A travel control method for controlling travel of a vehicle along a target trajectory, comprising: a cant acquisition step of acquiring a cant angle indicating a lateral inclination degree of a road surface on which the vehicle is traveling; a deviation calculation step of calculating a lateral deviation between the position of the target trajectory and the position of the vehicle in the lateral direction; a steering control step of calculating a target steering angle of the vehicle based on the cant angle and the lateral deviation, and controlling the steering of the vehicle to follow the target steering angle, The feedback term of the target steering angle calculated based on the cant angle and the lateral deviation is provided with a limit that is set variably according to the cant angle.
[0011] The present invention also provides A program for controlling vehicle travel along a target trajectory, a cant acquisition step of acquiring a cant angle indicating a lateral inclination degree of a road surface on which the vehicle is traveling; a deviation calculation step of calculating a lateral deviation between the position of the target trajectory and the position of the vehicle in the lateral direction; a steering control step of calculating a target steering angle of the vehicle based on the cant angle and the lateral deviation, and controlling the steering of the vehicle so as to follow the target steering angle; on the computer, The feedback term of the target steering angle calculated based on the cant angle and the lateral deviation is provided with a limit that is set variably according to the cant angle. [Effects of the Invention]
[0012] According to the present invention, when the inclination direction of the cant of the road surface changes suddenly, the increase in the lateral deviation of the vehicle from the target trajectory can be reduced, and deviation of the vehicle from the target trajectory can be suppressed. [Brief explanation of the drawings]
[0013] [Figure 1] 1 is a block diagram showing the internal configuration of a vehicle equipped with a cruise control device according to an embodiment of the present invention; [Figure 2] FIG. 1 is a diagram illustrating an example of a vehicle performing lane keeping control traveling on a canted road that slopes downward to the right. [Figure 3] FIG. 2 is a control block diagram of a cruise control device when a vehicle is traveling on a canted road. [Figure 4] 1 is a diagram showing an example of a state in which a vehicle is traveling on a canted road surface that suddenly changes from a downward slope to the right to a downward slope to the left; [Figure 5] FIG. 10 is a diagram for explaining a limit setting method. [Figure 6] 4 is an example of a flowchart of control executed by the driving control device. DETAILED DESCRIPTION OF THE INVENTION
[0014] DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A cruise control device, a cruise control method, and a program according to an embodiment of the present invention will be described below with reference to the accompanying drawings.
[0015] 1 is a block diagram showing the internal configuration of a vehicle 10. The vehicle 10 includes a sensor group 12 and The vehicle includes a navigation device 14, a communication device 15, an electric power steering system 40 (also referred to as an EPS (Electric Power Steering) system 40), a driving force control system 50, a braking force control system 60, and a cruise control device 100.
[0016] The sensor group 12 acquires various detection values used for control by the cruise control device 100. The sensor group 12 includes, for example, a camera 12a that captures images of the periphery of the vehicle 10, a vehicle speed sensor 12b that detects the speed of the vehicle 10, a lateral acceleration sensor 12c that detects the acceleration in the lateral direction (vehicle width direction) of the vehicle 10 (hereinafter also referred to as lateral acceleration), and a yaw rate sensor 12d that detects the yaw rate, which is the angular velocity around the vertical axis of the vehicle 10. Note that the sensor group 12 may further include other sensors, such as wheel sensors that detect the rotational speed of the wheels and a gyro sensor that detects each speed in a predetermined direction.
[0017] The navigation device 14 detects the current position of the vehicle 10 using, for example, a Global Positioning System (GPS), and provides the user with guidance on a route to the destination. The navigation device 14 has a storage device (not shown) that includes a map information database. The map information database may include road information such as the curvature of curved roads and information on the cant angle of the road surface, which will be described later.
[0018] The communication device 15 is a communication interface for communicating with an external device. For example, a mobile communication network such as a cellular line, Wi-Fi (registered trademark), Bluetooth (registered trademark), etc. may be used for communication between the vehicle 10 and the external device.
[0019] The EPS system 40 includes a steering angle sensor 41, a torque sensor 42, an EPS motor 43, a resolver 44, and an EPS ECU (Electronic Control Unit) 45. The steering angle sensor 41 detects the steering angle θst of a steering wheel 46. The torque sensor 42 detects the torque TQ applied to the steering wheel 46. The EPS motor 43 applies a driving force or a reaction force to a steering column 47 connected to the steering wheel 46, thereby enabling operation assistance of the steering wheel 46. The resolver 44 detects the rotation angle θm of the EPS motor 43. The EPS ECU 45 is responsible for overall control of the EPS system 40. Specifically, the EPS ECU 45 controls the steering of the steering wheel 46 based on commands from a steering control unit 133 of the cruise control device 100, which will be described later.
[0020] The driving force control system 50 has a driving ECU 51 and executes driving force control of the vehicle 10. The driving ECU 51 controls the driving force of the vehicle 10 by controlling a motor, an internal combustion engine, or the like, which are the driving sources of the vehicle 10, based on the accelerator operation of an accelerator pedal 52 by the user.
[0021] The braking force control system 60 has a braking ECU 61 and executes braking force control of the vehicle 10. The braking ECU 61 controls the braking force of the vehicle 10 by controlling a braking mechanism and the like based on a brake operation on a brake pedal 62 by a user.
[0022] The cruise control device 100 controls the driving of the vehicle 10, such as steering, driving, and braking, and has a driving assistance function that assists the driver in driving. As one of the driving assistance functions, the cruise control device 100 is configured to be capable of executing lane keeping control, which causes the vehicle 10 to travel on a target trajectory set within a lane, either without the driver's driving operation or by assisting the driver's driving operation. The target trajectory of the vehicle 10 is, for example, the center position of the lane on which the vehicle 10 is traveling, more specifically, the lane center line, which is the center position of the white lines set on both the left and right sides of the lane.
[0023] The driving control device 100 has an input / output unit 110, a storage unit 120, and a calculation unit 130. The calculation unit 130 is configured by, for example, a CPU (Central Processing Unit). The calculation unit 130 performs various controls by controlling each unit based on a program stored in the storage unit 120. The calculation unit 130 also inputs and outputs signals to and from each unit connected to the driving control device 100 via the input / output unit 110.
[0024] The calculation unit 130 includes, for example, a cant acquisition unit 131 that acquires the cant angle of a road surface having a cant, which is the lateral inclination of the road (hereinafter also referred to as a canted road), a deviation calculation unit 132 that calculates the lateral deviation between the position of the target trajectory of the vehicle 10 in the lateral direction and the current position of the vehicle 10, and a steering control unit 133 that controls the steering of the vehicle 10.
[0025] The cant acquisition unit 131 acquires a cant angle based on the detection results of the sensor group 12, such as the lateral acceleration of the vehicle 10 detected by the lateral acceleration sensor 12c and the yaw rate of the vehicle 10 detected by the yaw rate sensor 12d. The cant angle indicates the degree of inclination of a canted road in the lateral direction. The cant angle can be detected by various methods. For example, the cant acquisition unit 131 may acquire the cant angle using a sensor (including the camera 12a) that detects the inclination of the road surface. Specifically, the cant acquisition unit 131 may acquire the cant angle based on the detection results of the camera 12a. Alternatively, if the sensor group 12 has an inclination sensor that detects the inclination angle of the vehicle 10 in the vehicle width direction, the cant acquisition unit 131 may acquire the cant angle based on the detection results of the inclination sensor. Furthermore, the cant acquisition unit 131 may acquire information on the cant angle of a road that is registered in advance in a map information database or the like.
[0026] The deviation calculation unit 132 calculates the lateral deviation between the position of the target track of the vehicle 10 in the lateral direction and the current position of the vehicle 10 based on the information detected by the camera 12a or the like.
[0027] The steering control unit 133 transmits a steering control command to the EPS system 40 so that the vehicle 10 travels along the target trajectory.
[0028] Fig. 2 shows an example of a vehicle 10 performing lane keeping control traveling on a canted road that slopes downward to the right. Note that Fig. 2 (and Fig. 4, which will be described later) depicts the canted road as a straight line in the traveling direction of the vehicle 10, but it may also be a curved road (i.e., a curved road).
[0029] When the vehicle 10 travels on a canted road, a rightward yaw rate occurs with respect to the target trajectory L0 (dash-dotted line), causing the vehicle 10 to drift to the right of the target trajectory L0 and deviate from the target trajectory L0. Therefore, the cruise control device 100 executes control by lane keeping control to prevent the vehicle 10 from drifting to the right and return the vehicle 10 to the target trajectory L0. The target steering angle of the vehicle 10 at this time is set to the left, which is the opposite direction to the direction in which the vehicle 10 drifts due to cant, with respect to a reference steering angle that follows the target trajectory L0 when there is no cant. Furthermore, although not shown, when the vehicle 10 travels on a canted road that slopes downward to the left, a leftward yaw rate occurs with respect to the target trajectory L0, causing the vehicle 10 to drift to the left of the target trajectory L0 and deviate from the target trajectory L0. Therefore, the cruise control device 100 executes control by lane keeping control to prevent the vehicle 10 from drifting to the left and return the vehicle 10 to the target trajectory L0. The target steering angle of the vehicle 10 at this time is set to the right, which is the opposite direction to the direction in which the vehicle 10 drifts due to cant, with respect to the reference steering angle that follows the target trajectory L0 when there is no cant.
[0030] 3 shows a control block diagram of the cruise control device 100 when the vehicle 10 is traveling on a canted road. The cruise control device 100 calculates a target steering angle through feedforward control and feedback control. In the following description and in the drawings, "feedforward" is also abbreviated as "FF" and "feedback" is also abbreviated as "FB."
[0031] Cruise control device 100 calculates a target steering angle based on FF term 101 based on the cant angle, FB integral term 102 for cant compensation, and FB integral term 103 based on lateral deviation. FF term 101 is a term that ensures high responsiveness, and FB integral terms 102 and 103 are terms that compensate for modeling errors and the effects of disturbances with respect to FF term 101.
[0032] The FF term 101 of the target steering angle is set based on the cant angle detected by the cant acquisition unit 131. The FF term 101 is set, for example, by a mathematical expression, a map, or the like that indicates a predetermined relationship between the cant angle and the target steering angle.
[0033] The FB integral term 102 of the target steering angle is a term that suppresses lateral drift of the vehicle 10 due to cant through feedback control, and is set based on the cant angle and lateral deviation. Specifically, the FB integral term 102 is a term that corrects the target steering angle so that the lateral deviation caused by cant does not increase while the vehicle 10 is traveling on a canted road.
[0034] The FB integral term 103 of the target steering angle is a term that brings the lateral deviation closer to zero by feedback control, bringing the vehicle 10 closer to the target trajectory L0, and is set based on the lateral deviation. Specifically, the FB integral term 103 is a term that corrects the target steering angle in a direction that reduces the lateral deviation while the vehicle 10 is traveling on a canted road.
[0035] The cruise control device 100 calculates a target steering angle by adding an FB integral term 102 and an FB integral term 103 to an FF term 101, and controls the steering of the vehicle 10 so as to follow the target steering angle.
[0036] 4, when the canted road in the traveling direction of the vehicle 10 suddenly changes from a downslope to the right to a downslope to the left, a state may occur in which the target steering angle to the left corresponding to the downslope to the right (more specifically, the target steering angle to the left relative to the reference steering angle described above) remains temporarily after the sudden change in the direction of the inclination. This is due to, for example, a delay in the operation of the steering wheel 46 by the EPS system 40, a delay in the feedback control by the cruise control device 100, a delay in obtaining the cant angle, etc. In this case, the direction in which the vehicle 10 drifts due to the downslope to the left and the direction of the target steering angle of the vehicle 10 are both to the left, so the lateral deviation of the vehicle 10 increases to the left, and there is a risk that the vehicle 10 will deviate significantly from the target trajectory L0.
[0037] Therefore, as shown in Fig. 3, the FB integral term 102 for cant compensation is provided with a limit 104 that is set variably according to the cant angle. Because the FB integral term 102 is provided with the limit 104, the calculated target steering angle does not become larger than necessary in response to the lateral drift of the vehicle 10 caused by cant. Therefore, even if the inclination direction of the canted road changes suddenly, it is possible to reduce an increase in the lateral deviation of the vehicle 10 with respect to the target trajectory L0, and to suppress deviation of the vehicle 10 from the target trajectory L0.
[0038] More specifically, the cruise control device 100 calculates the target steering angle by adding an FB integral term 102, which is calculated based on the cant angle and lateral deviation and has a limit 104, to an FF term calculated based on the cant angle, so that the target steering angle can be appropriately set by FF control and FB control based on the cant angle and lateral deviation.
[0039] 5(a) to 5(d) are graphs for explaining how to set the limit 104. In the four graphs, the horizontal axis represents the cant angle and the vertical axis represents the yaw rate. In this specification, the cant angle of a canted road that slopes downward to the left is defined as a positive value, and the cant angle of a canted road that slopes downward to the right is defined as a negative value. In addition, the yaw rate and steering angle in the right direction relative to a reference steering angle that corresponds to a leftward downward slope and follows the target trajectory L0 when there is no cant are defined as positive values, and the yaw rate and steering angle in the left direction relative to the reference steering angle are defined as negative values.
[0040] First, the cruise control device 100 calculates an optimum yaw rate for the lateral drift of the vehicle 10 due to cant. Specifically, the cruise control device 100 calculates an upper limit value of the yaw rate (hereinafter also referred to as the yaw rate upper limit value) that can suppress the lateral drift of the vehicle 10 due to cant without increasing the target steering angle more than necessary, and sets an optimum yaw rate that does not exceed the upper limit value. The yaw rate upper limit value is calculated, for example, based on the following formula (1), and the graph is represented by the thick solid curve in Figure 5(a).
[0041] γ=Av / (1+Av 2 )×gsinθ (1)
[0042] Here, γ is the upper limit of the yaw rate, A is a stability factor indicating the maneuverability of the vehicle 10, v is the speed of the vehicle 10, g is the acceleration due to gravity, and θ is the cant angle of the canted road. The upper limit of the yaw rate is a function of the cant angle and varies depending on the cant angle. In this specification, when the cant angle is positive, the upper limit of the yaw rate takes a positive value (i.e., rightward), and when the cant angle is negative, the upper limit of the yaw rate takes a negative value (i.e., leftward).
[0043] The yaw rate upper limit value is not limited to the above formula (1), but may be calculated by, for example, further taking into consideration specification information of the vehicle 10, specifically information such as the vehicle weight and wheelbase, in addition to the above formula (1).
[0044] After calculating the yaw rate upper limit, the cruise control device 100 identifies a first prohibited area R1 (the shaded area in FIG. 5(a)) where the yaw rate of the vehicle 10 exceeds the yaw rate upper limit. If the target steering angle is set so that the yaw rate falls within the first prohibited area R1, the target steering angle will be larger than necessary. Therefore, the cruise control device 100 calculates an optimal target steering angle so that the yaw rate does not fall within the first prohibited area R1. Specifically, when the cant angle is equal to or greater than zero, the area above the yaw rate upper limit becomes the first prohibited area R1. Furthermore, when the cant angle is less than zero, the area below the yaw rate upper limit becomes the first prohibited area R1.
[0045] Next, as shown in FIG. 5(b), the cruise control device 100 identifies a second prohibited area R2 that satisfies the condition that the direction of the yaw rate does not match the direction in which the vehicle 10 is moving due to cant. If the yaw rate falls within the second prohibited area R2, the target steering angle is set in a direction that increases lateral deviation. Therefore, the cruise control device 100 calculates the target steering angle so that the yaw rate does not fall within the second prohibited area R2. Specifically, when the cant angle is equal to or greater than zero, the second prohibited area R2 is the area where the yaw rate is negative, i.e., the area where the yaw rate is leftward relative to the reference steering angle. On the other hand, when the cant angle is less than zero, the second prohibited area R2 is the area where the yaw rate is positive, i.e., the area where the yaw rate is rightward relative to the reference steering angle.
[0046] Next, as shown in Figure 5(c), the cruise control device 100 combines the first prohibited area R1 and the second prohibited area R2 identified in Figures 5(a) and 5(b). The cruise control device 100 sets the lower edge of the first prohibited area R1 and the second prohibited area R2 (hereinafter also referred to as upper boundary 104a) on the upper side of the graph and the upper edge of the first prohibited area R1 and the second prohibited area R2 (hereinafter also referred to as lower boundary 104b) on the lower side as limits. Note that the "limits" here are the values before adjustment shown in Figure 5(d).
[0047] Finally, as shown in Figure 5(d), the cruise control device 100 adjusts the limit so that it functions even when the cant angle is near zero. This reduces control noise. Specifically, when the cant angle is near zero, the upper boundary 104a and the lower boundary 104b are blunted, and a predetermined width is provided between the upper boundary 104a and the lower boundary 104b, completing the setting of the limit 104 shown in Figure 3.
[0048] The cruise control device 100 sets the target steering angle so that the yaw rate does not exceed the limit 104, specifically so that the yaw rate does not exceed the upper boundary 104a of the limit 104 and does not become smaller than the lower boundary 104b of the limit 104.
[0049] The limit 104 described above is set, for example, when lateral movement of the vehicle 10 based on the canted road is detected; in other words, it is set before the inclination direction of the canted road changes suddenly. This allows the limit 104 to be set appropriately in advance before the inclination direction of the canted road changes suddenly. However, the timing for setting the limit 104 is not limited to this. The limit 104 may be set when a canted road ahead is detected by the camera 12a or the like before traveling on the canted road (i.e., while traveling on a flat road). Alternatively, the limit 104 may be set by referring to a map information database while traveling on a flat road, recognizing the canted road in advance, obtaining information about the cant angle, and then setting the limit 104.
[0050] Fig. 6 shows an example of a flowchart of control executed by the driving control device 100. The driving control device 100 repeatedly executes the flowchart of Fig. 6 at a predetermined cycle.
[0051] The cruise control device 100 determines whether or not lateral movement of the vehicle 10 due to cant has been detected (step S1). If lateral movement has not been detected (step S1: NO), the cruise control device 100 ends this flowchart.
[0052] If a lateral movement is detected (step S1: YES), the cruise control device 100 acquires the cant angle of the road surface (step S2) and calculates the lateral deviation of the vehicle 10 (step S3). Note that steps S2 and S3 may be performed in reverse order, or may be performed simultaneously.
[0053] Next, the cruise control device 100 sets the limit 104 using the method described above (step S4), and calculates the target steering angle taking the limit 104 into consideration (step S5). Then, the cruise control device 100 controls the steering of the vehicle 10 so that the steering angle follows the target steering angle (step S6).
[0054] The control method described in the above-described embodiment can be realized by executing a prepared program on a computer. The program is stored in a computer-readable storage medium and executed by being read from the storage medium. The program may be provided in a form stored in a non-transitory storage medium such as a flash memory, or may be provided via a network such as the Internet. The computer that executes the program may be included in a control device, or may be included in an electronic device such as a smartphone, tablet, or personal computer that can communicate with the control device, or may be included in a server device that can communicate with these control devices and electronic devices.
[0055] Although one embodiment of the present invention has been described above with reference to the accompanying drawings, it goes without saying that the present invention is not limited to such an embodiment. It is clear that a person skilled in the art can conceive of various modifications or alterations within the scope of the claims, and it is understood that these also naturally fall within the technical scope of the present invention. Furthermore, the components of the above embodiment may be combined in any manner without departing from the spirit of the invention.
[0056] For example, when the vehicle 10 is traveling on a canted road and there is a large difference between the current steering angle and the target steering angle, a limit may be imposed on the amount of change in the steering angle per unit time to bring the steering angle closer to the target steering angle. This makes it possible to suppress a sudden increase in the yaw rate of the vehicle 10.
[0057] In addition, in order to reduce unnecessary steering control by the driving control device 100 when the vehicle 10 is traveling on a road surface without cant, a dead zone may be provided in which steering control based on the cant angle is not performed when the cant angle is close to zero.
[0058] Furthermore, in the embodiment described above, the cruise control device 100 calculates the target steering angle by adding the FB integral term 102 for cant compensation and the FB integral term 103 based on the lateral deviation to the FF term 101, but the target steering angle may also be calculated by further adding an FB differential term based on the lateral deviation, an FB term based on the attitude angle, etc.
[0059] Furthermore, in the above-described embodiment, the driving control device 100 calculates the limit 104 based on predetermined information about the vehicle 10 (for example, vehicle speed, stability factor, specification information, etc.), but the limit 104 may also be calculated by further taking into consideration, for example, the slip angle and the friction coefficient of the road surface.
[0060] This specification describes at least the following: In parentheses, components corresponding to those in the above-described embodiments are shown as examples, but the present invention is not limited to these.
[0061] (1) A cruise control device (cruise control device 100) that controls the travel of a vehicle (vehicle 10) along a target trajectory (target trajectory L0), a cant acquisition unit (cant acquisition unit 131) that acquires a cant angle indicating the degree of lateral inclination of a road surface on which the vehicle is traveling; a deviation calculation unit (deviation calculation unit 132) that calculates a lateral deviation between the position of the target trajectory and the position of the vehicle in the lateral direction; a control unit (steering control unit 133) that calculates a target steering angle of the vehicle based on the cant angle and the lateral deviation, and controls the steering of the vehicle to follow the target steering angle, A feedback term (FB integral term 102) of the target steering angle calculated based on the cant angle and the lateral deviation is provided with a limit (limit 104) that is variably set according to the cant angle. Driving control device.
[0062] When the inclination direction of the road surface cant suddenly changes (specifically, when it suddenly changes from right to left or from left to right), the cant can cause a state in which the steering remains in the direction in which the vehicle is moving, which can cause the vehicle to deviate from the target trajectory. According to (1), the feedback term for the target steering angle is provided with a limit that is variably set according to the cant angle, so even when the inclination direction of the road surface cant suddenly changes, it is possible to reduce the increase in the lateral deviation of the vehicle from the target trajectory and suppress the deviation of the vehicle from the target trajectory. Furthermore, even when the road surface suddenly changes from a canted road to a non-canted road, it is possible to reduce the increase in the lateral deviation of the vehicle from the target trajectory and suppress the deviation of the vehicle from the target trajectory.
[0063] (2) The driving control device according to (1), The limit is: a yaw rate upper limit value that is variably set depending on the cant angle and calculated based on predetermined information about the vehicle; a condition in which the direction of the yaw rate of the vehicle does not coincide with the downward slope direction of the road surface; It is set based on Driving control device.
[0064] According to (2), the limit set based on the yaw rate of the vehicle can prevent the target steering angle from being set in a direction that increases the lateral deviation of the vehicle.
[0065] (3) The driving control device according to (2), The yaw rate upper limit value is calculated based on the speed of the vehicle. Driving control device.
[0066] According to (3), an appropriate limit can be set taking into account the vehicle speed.
[0067] (4) The driving control device according to (2) or (3), The yaw rate upper limit value is calculated based on specification information of the vehicle. Driving control device.
[0068] According to (4), it is possible to set an appropriate limit taking into account the vehicle specification information.
[0069] (5) A driving control device according to any one of (1) to (4), the control unit sets the limit when movement of the vehicle in the lateral direction based on cant of the road surface is detected. Driving control device.
[0070] According to (5), the limit can be set appropriately in advance before the direction of the cant of the road surface changes suddenly.
[0071] (6) A driving control device according to any one of (1) to (5), The cant acquisition unit acquires the cant angle based on at least one of a detection result by a sensor (lateral acceleration sensor 12c, yaw rate sensor 12d) that detects the acceleration of the vehicle, a detection result by a sensor (inclination sensor, camera 12a) that detects the inclination of the road surface, and map information. Driving control device.
[0072] According to (6), the cant angle can be appropriately obtained based on sensors, map information, etc.
[0073] (7) A driving control device according to any one of (1) to (6), The control unit calculates the target steering angle by adding the feedback term, which is calculated based on the cant angle and the lateral deviation and to which the limit is set, to a feedforward term (FF term 101) calculated based on the cant angle. Driving control device.
[0074] According to (7), the target steering angle can be appropriately set by feedforward control and feedback control based on the cant angle and lateral deviation.
[0075] (8) A travel control method for controlling travel of a vehicle (vehicle 10) along a target trajectory (target trajectory L0), comprising: a cant acquisition step of acquiring a cant angle indicating a lateral inclination degree of a road surface on which the vehicle is traveling; a deviation calculation step of calculating a lateral deviation between the position of the target trajectory and the position of the vehicle in the lateral direction; a steering control step of calculating a target steering angle of the vehicle based on the cant angle and the lateral deviation, and controlling the steering of the vehicle to follow the target steering angle, A feedback term (FB integral term 102) of the target steering angle calculated based on the cant angle and the lateral deviation is provided with a limit (limit 104) that is variably set according to the cant angle. Driving control method.
[0076] When the inclination direction of the cant of the road surface changes suddenly (specifically, when it changes suddenly from right to left or from left to right), the cant causes a state in which the steering remains in the direction in which the vehicle is moving, and there is a risk that the vehicle will deviate from the target trajectory.According to (8), the feedback term of the target steering angle is provided with a limit that is set variably according to the cant angle, so even when the inclination direction of the cant of the road surface changes suddenly, it is possible to reduce the increase in the lateral deviation of the vehicle from the target trajectory and suppress the deviation of the vehicle from the target trajectory.
[0077] (9) A program for controlling the running of a vehicle (vehicle 10) along a target trajectory (target trajectory L0), a cant acquisition step of acquiring a cant angle indicating a lateral inclination degree of a road surface on which the vehicle is traveling; a deviation calculation step of calculating a lateral deviation between the position of the target trajectory and the position of the vehicle in the lateral direction; a steering control step of calculating a target steering angle of the vehicle based on the cant angle and the lateral deviation, and controlling the steering of the vehicle so as to follow the target steering angle; The computer (driving control device 100) executes the above. A feedback term (FB integral term 102) of the target steering angle calculated based on the cant angle and the lateral deviation is provided with a limit (limit 104) that is variably set according to the cant angle. program.
[0078] When the inclination direction of the cant of the road surface changes suddenly (specifically, when it changes suddenly from right to left or from left to right), the cant causes a state in which the steering remains in the direction in which the vehicle is flowing, and there is a risk that the vehicle will deviate from the target trajectory.According to (9), the feedback term of the target steering angle is provided with a limit that is variably set according to the cant angle, so even when the inclination direction of the cant of the road surface changes suddenly, it is possible to reduce the increase in the lateral deviation of the vehicle from the target trajectory and suppress the deviation of the vehicle from the target trajectory. [Explanation of symbols]
[0079] 10 vehicles 12a Camera (sensor) 12c Lateral acceleration sensor (sensor) 12d Yaw rate sensor (sensor) 100 Driving control device 101 FF term (feedforward term) 102 FB integral term (feedback term) 104 Limit 131 Cant Acquisition Department 132 Deviation calculation unit 133 Steering control unit (control unit)
Claims
1. A driving control device that controls driving of a vehicle so as to follow a target trajectory, a cant acquisition unit that acquires a cant angle that indicates a lateral inclination degree of a road surface on which the vehicle is traveling; a deviation calculation unit that calculates a lateral deviation between the position of the target trajectory and the position of the vehicle in the lateral direction; a control unit that calculates a target steering angle of the vehicle based on the cant angle and the lateral deviation, and controls steering of the vehicle to follow the target steering angle, a limit set variably in accordance with the cant angle is provided to a feedback term of the target steering angle calculated based on the cant angle and the lateral deviation; Driving control device.
2. The travel control device according to claim 1, The limit is: a yaw rate upper limit value that is variably set depending on the cant angle and calculated based on predetermined information about the vehicle; a condition in which the direction of the yaw rate of the vehicle does not coincide with the downward slope direction of the road surface; It is set based on Driving control device.
3. The travel control device according to claim 2, The yaw rate upper limit value is calculated based on the speed of the vehicle. Driving control device.
4. The travel control device according to claim 2, The yaw rate upper limit value is calculated based on specification information of the vehicle. Driving control device.
5. The travel control device according to claim 1, the control unit sets the limit when movement of the vehicle in the lateral direction based on cant of the road surface is detected. Driving control device.
6. The travel control device according to claim 1, the cant acquisition unit acquires the cant angle based on at least one of a detection result by a sensor that detects a lateral acceleration of the vehicle, a detection result by a sensor that detects an inclination of the road surface, and map information. Driving control device.
7. A travel control device according to any one of claims 1 to 6, the control unit calculates the target steering angle by adding the feedback term, which is calculated based on the cant angle and the lateral deviation and to which the limit is set, to a feedforward term calculated based on the cant angle. Driving control device.
8. A travel control method for controlling travel of a vehicle along a target trajectory, comprising: a cant acquisition step of acquiring a cant angle indicating a lateral inclination degree of a road surface on which the vehicle is traveling; a deviation calculation step of calculating a lateral deviation between the position of the target trajectory and the position of the vehicle in the lateral direction; a steering control step of calculating a target steering angle of the vehicle based on the cant angle and the lateral deviation, and controlling the steering of the vehicle to follow the target steering angle, a limit set variably in accordance with the cant angle is provided to a feedback term of the target steering angle calculated based on the cant angle and the lateral deviation; Driving control method.
9. A program for controlling vehicle travel along a target trajectory, a cant acquisition step of acquiring a cant angle indicating a lateral inclination degree of a road surface on which the vehicle is traveling; a deviation calculation step of calculating a lateral deviation between the position of the target trajectory and the position of the vehicle in the lateral direction; a steering control step of calculating a target steering angle of the vehicle based on the cant angle and the lateral deviation, and controlling the steering of the vehicle so as to follow the target steering angle; on the computer, a limit set variably in accordance with the cant angle is provided to a feedback term of the target steering angle calculated based on the cant angle and the lateral deviation; program.