Vehicle control device, vehicle control method, and vehicle control program

Abstract

A control device (30, 60) is configured so as to execute linear conversion processing, linearization processing, and operation processing. The linear conversion processing is for linearly converting a value of an input variable into a value of an intermediate variable. The input variable in the linear conversion processing is a variable related to a control amount for controlling the trajectory of a vehicle along a target trajectory. The linearization processing is for converting the value of the intermediate variable into a value of a target variable on the basis of a value of a travel direction variable, the vehicle speed, and a value of a trajectory curvature variable as input variables. The operation processing is for operating an actuator on the basis of the value of the target variable as an input variable.

Description

Vehicle control device, vehicle control method, and vehicle control program

[0001] The present disclosure relates to a vehicle control device, a vehicle control method, and a vehicle control program.

[0002] For example, Patent Document 1 listed below describes a device that calculates a target steering angle for a vehicle traveling around a curve based on a forward gaze model.

[0003] Japanese Patent Application Laid-Open No. 2021-17217

[0004] In the case of the above-mentioned device, the control response varies depending on the curvature of the curve on which the vehicle is traveling, and therefore the controllability is likely to deteriorate.

[0005] One aspect of the present disclosure provides a vehicle control device that operates a predetermined actuator to change the driving direction of the vehicle. The vehicle control device is configured to execute a linear transformation process, a linearization process, and an operation process. The linear transformation process is a process of linearly transforming values ​​of input variables into values ​​of intermediate variables. The input variables of the linear transformation process are variables related to control amounts for controlling the trajectory of the vehicle to follow a target trajectory. The linearization process is a process of converting values ​​of the intermediate variables into values ​​of target variables based on values ​​of a driving direction variable, a vehicle speed, and a trajectory curvature variable, which are input variables. The driving direction variable is a variable that indicates the driving direction of the vehicle. The trajectory curvature variable is a variable that indicates a curvature related to the target trajectory. The target variable is a variable that indicates a target value for a change in the driving direction of the vehicle. The operation process is a process of operating the actuator based on values ​​of the target variables, which are input variables.

[0006] Another aspect of the present disclosure provides a vehicle control method for operating a predetermined actuator to change the vehicle's traveling direction. The vehicle control method includes executing a linear transformation process, a linearization process, and an operation process. The linear transformation process is a process for linearly transforming values ​​of input variables into values ​​of intermediate variables. The input variables of the linear transformation process are variables related to control amounts for controlling the vehicle's trajectory to follow a target trajectory. The linearization process is a process for converting values ​​of the intermediate variables into values ​​of target variables based on values ​​of a traveling direction variable, a vehicle speed, and a trajectory curvature variable, which are input variables. The traveling direction variable is a variable indicating the vehicle's traveling direction. The trajectory curvature variable is a variable indicating a curvature related to the target trajectory. The target variable is a variable indicating a target value for change in the vehicle's traveling direction. The operation process is a process for operating the actuator based on values ​​of the target variables, which are input variables.

[0007] Another aspect of the present disclosure provides a vehicle control program for operating a predetermined actuator to change the vehicle's traveling direction. The vehicle control program includes instructions for causing a computer to execute a linear transformation process, a linearization process, and an operation process. The linear transformation process is a process for linearly transforming values ​​of input variables into values ​​of intermediate variables. The input variables of the linear transformation process are variables related to control amounts for controlling the vehicle's trajectory to follow a target trajectory. The linearization process is a process for converting values ​​of the intermediate variables into values ​​of target variables based on values ​​of a traveling direction variable, a vehicle speed, and a trajectory curvature variable, which are input variables. The traveling direction variable is a variable indicating the vehicle's traveling direction. The trajectory curvature variable is a variable indicating a curvature related to the target trajectory. The target variable is a variable indicating a target value for a change in the vehicle's traveling direction. The operation process is a process for operating the actuator based on values ​​of the target variables, which are input variables.

[0008] It is a block diagram showing the configuration of a vehicle according to one embodiment.It is a block diagram showing the process executed by a control device mounted on the vehicle shown in Figure 1.It is a diagram showing a model used in the process shown in Figure 2.

[0009] An embodiment will be described below with reference to the drawings. "Vehicle Configuration" Fig. 1 shows the configuration of a vehicle according to this embodiment. As shown in Fig. 1, the vehicle is equipped with a steering system 10. A steering wheel 12 provided in the steering system 10 is mechanically connected to a steering shaft 14. A reaction torque that resists the operation of the steering wheel 12 is applied to the steering shaft 14 by a reaction motor 16. The reaction motor 16 is configured so that the output voltage of an inverter 18 is applied to its terminals.

[0010] The steered wheels 20 included in the steering system 10 are steered by the torque of a steering motor 22. The output voltage of an inverter 24 is applied to the terminals of the steering motor 22. The steering control device 30 included in the steering system 10 includes a PU 32 and a storage device 34. The PU 32 is a processing unit that executes software processing. The PU 32 may be a CPU. The PU 32 may be a GPU. The PU 32 controls the control amount of the control object by executing a program stored in the storage device 34.

[0011] The control object of the steering control device 30 is the steering shaft 14. The steering control device 30 operates the inverter 18 to control the torque applied to the steering shaft as a control variable. The control object of the steering control device 30 is the steered wheels 20. The steering control device 30 operates the inverter 24 to control the steering angle of the steered wheels 20 as a control variable.

[0012] In order to control the control amount, steering control device 30 refers to the rotation angle θmh of reaction force motor 16 detected by rotation angle sensor 40. In order to control the control amount, steering control device 30 refers to the rotation angle θmt of steering motor 22 detected by rotation angle sensor 42.

[0013] The vehicle includes a drivetrain 50. The drivetrain 50 includes at least one of an internal combustion engine and a rotating electric machine as a thrust generating device for the vehicle. The vehicle includes a braking system 52. The braking system 52 includes at least one of a device that slows down the rotation of the wheels by frictional force and a device that slows down the rotation of the wheels by converting the power of the wheels into electrical energy. Note that the device that slows down the rotation of the wheels by converting into electrical energy may be shared with the rotating electric machine of the drivetrain.

[0014] The vehicle includes an ADASECU 60. The ADASECU 60 includes a PU 62 and a storage device 64. The PU 62 is a processing unit that executes software processing. The PU 62 may be, for example, a CPU. The PU 62 may be a GPU. The PU 62 controls the control amount of a control target by executing a program stored in the storage device 64.

[0015] The ADASECU 60 controls a vehicle. The ADASECU 60 executes a process to assist the driving of the vehicle. More specifically, the ADASECU 60 executes a process to control the behavior of the vehicle.

[0016] The ADASECU 60 references the vehicle speed v detected by the vehicle speed sensor 70 to control the controlled object. The ADASECU 60 references image data Do generated by a camera 72 that captures images of the vehicle's surroundings to control the controlled object. The ADASECU 60 references position data Dgps obtained by a global positioning system (GPS 74) to control the controlled object. The ADASECU 60 references map data 78 to control the controlled object.

[0017] "Driving Assistance" Fig. 2 shows the processing related to driving assistance according to this embodiment. The processing shown in Fig. 2 is executed by the steering control device 30 and the ADASECU 60 working together. In particular, of the processing shown in Fig. 2, the base value setting processing M10, the superimposition processing M36, and the operation signal generation processing M38 are realized by the PU 32 repeatedly executing programs stored in the storage device 34, for example, at predetermined intervals. The remaining processing shown in Fig. 2 is realized by the PU 62 repeatedly executing programs stored in the storage device 64, for example, at predetermined intervals.

[0018] The base value setting process M10 is a process for setting a target steering equivalent angle base value θp*0 based on the steering angle θh and vehicle speed v as input variables. The steering angle θh is calculated by the PU 32 based on the rotation angle θmh as an input variable. The target steering equivalent angle base value θp*0 is a target value for the steering equivalent angle θp. The steering equivalent angle θp is a variable that indicates the steering angle of the steered wheels 20. The steering equivalent angle θp is a variable that has a one-to-one correspondence with the steering angle.

[0019] The base value setting process M10 includes a process for changing the target steering equivalent angle base value θp*0 in accordance with the steering angle θh under the following condition: the absolute value of the target steering equivalent angle base value θp*0 when the absolute value of the steering angle θh is large is equal to or greater than the absolute value of the target steering equivalent angle base value θp*0 when the absolute value of the steering angle θh is small. However, when the steering angle θh is a value on the right-turning side, the target steering equivalent angle base value θp*0 is also set to a value on the right-turning side. Furthermore, when the steering angle θh is a value on the left-turning side, the target steering equivalent angle base value θp*0 is also set to a value on the left-turning side.

[0020] In the description "changing B according to A while satisfying the condition that when A is large, B is equal to or greater than B when A is small," the case where A is large and the case where A is small refer to the relative relationship of magnitude when comparing the two. For example, "when A is large" corresponds to the case where "A is a first value," and "when A is small" corresponds to the case where "A is a second value smaller than the first value." Furthermore, the above description means that, depending on the settings of the first and second values, B when A is the first value may be larger than B when A is the second value. Furthermore, the above description means that B is changed according to A so that A when B is large is larger than A when B is small.

[0021] The lateral deviation calculation process M20 is a process for calculating the lateral deviation z. The lateral deviation z is shown in Fig. 3. The target trajectory tr* shown in Fig. 3 is a set of target values ​​for the trajectory of the center of gravity of the vehicle. The lateral deviation z is the minimum absolute value of the difference between the center of gravity of the vehicle and the target trajectory tr*.

[0022] In FIG. 3, the first inertial basis e1 and the second inertial basis e2 indicate orthonormal bases of the inertial coordinate system. Also in FIG. 3, the first trajectory basis e1' and the second trajectory basis e2' indicate orthonormal bases at each point on the target trajectory tr*. Here, the first trajectory basis e1' indicates the tangent direction of the target trajectory tr*. The lateral deviation z is the minimum value of the length of the perpendicular line drawn from the center of gravity of the vehicle to the first trajectory basis e1'. Point P in FIG. 3 indicates the intersection of the perpendicular line and the target trajectory tr*.

[0023] 3, the speed direction angle θ0 is the angle between the first inertial base e1 and the traveling direction of the vehicle, and the trajectory direction angle θr is the angle between the first trajectory base e1' and the first inertial base e1.

[0024] The PU 62 sets the target trajectory tr* based on the image data Do, the position data Dgps, and the map data 78. The PU 62 also identifies the actual position of the vehicle in addition to the position of the target trajectory tr* on the lane. The lateral deviation calculation process M20 is a process for calculating the lateral deviation z in accordance with the identification result of the target trajectory tr* and the actual position of the vehicle.

[0025] Returning to FIG. 2 , the target lateral deviation setting process M22 is a process for setting a target lateral deviation z*0, which is a target value for the lateral deviation z. The target lateral deviation z*0 may be zero. When the target trajectory tr* is along the center of the leftmost lane, the target lateral deviation z*0 may be a value set so that the vehicle is positioned a predetermined distance to the right. Note that, for example, the PU 62 may change the target lateral deviation z*0 in accordance with the width of the road on which the vehicle is traveling. Furthermore, for example, the PU 62 may change the target lateral deviation z*0 in accordance with the driver's steering. Specifically, the PU 62 may change the target lateral deviation z*0 in accordance with the magnitude of the torque input to the steering shaft 14 by the driver, for example.

[0026] The deviation calculation process M24 is a process of substituting a value obtained by subtracting the lateral deviation z from the target lateral deviation z* corresponding to the target lateral deviation z*0 for the deviation Δz. The linear conversion process M26 is a process of converting the deviation Δz into a closed-loop intermediate variable ufb. The linear conversion process M26 sets the relationship of the closed-loop intermediate variable ufb with respect to the lateral deviation z to a linear relationship. More specifically, the linear conversion process M26 is expressed, as an example, by the transfer function shown in the following equation (c1).

[0027] {s (ω^2)} / {s+2ω} (c1) where "s" is a differential operator and "^2" indicates a square. This transfer function is obtained by setting the linear relationship between the deviation Δz and the closed-loop intermediate variable ufb to the relationship shown in the following equation (c2), and by setting the responsiveness of the lateral deviation z to the target lateral deviation z* to the following equation (c3). Here, the variable ω is a variable that defines the responsiveness.

[0028] z={1 / (s^2)}·ufb (c2) z=[1 / {1+(1 / ω)·s}^2]·z* (c3) The linear conversion process M28 converts the target lateral deviation z*0 into an open-loop intermediate variable uff. The linear conversion process M28 sets the relationship between the target lateral deviation z*0 and the open-loop intermediate variable uff to a linear relationship. Here, the relationship between the target lateral deviation z*0 and the open-loop intermediate variable uff is equal to the relationship between the lateral deviation z and the closed-loop intermediate variable ufb shown in the above equation (c2).

[0029] The addition process M30 is a process of substituting the sum of the closed-loop intermediate variable ufb and the open-loop intermediate variable uff for the intermediate variable u. The linearization process M32 is a process of calculating a target curvature κ* based on the intermediate variable u, vehicle speed v, angle deviation θ, and trajectory curvature κr as input variables. Here, the angle deviation θ is a value obtained by subtracting the trajectory direction angle θr from the speed direction angle θ0 shown in FIG. 3. The angle deviation θ is a traveling direction variable that indicates the traveling direction of the vehicle. The trajectory curvature κr indicates the curvature of the target trajectory tr* at point P in FIG. 3. The target curvature κ* is a target value of the curvature of the route along which the vehicle should travel. The trajectory curvature κr as an input variable of the linearization process M32 may be calculated by the PU 62, for example, by polynomial approximation of the target trajectory tr*.

[0030] The linearization process M32 is a process for calculating the target curvature κ* based on the following equation (c4): κ*=-(tan θ / v^2)·(dv / dt)+{1 / (cos θ·v^2)}·u+{cos θ / (1-kr·z)}·κr (c4) This equation is derived from the state equation expressed by the following equations (c5) to (c7).

[0031] dθ / dt=κv-κr{(vcosθ) / (1-κrz)} (c5) ds / dt={(vcosθ) / (1-κrz)} (c6) dz / dt=vsinθ (c7) where the vehicle curvature κ and the path length s are used. The path length s is the length of the path from the reference point to the current time on the target trajectory tr*.

[0032] When the above equation (c5) is solved for the curvature κ, the following equation (c8) is obtained: κ=(1 / v)·(dθ / dt)+κr·{cos θ / (1−κr·z)} (c8) Meanwhile, in this embodiment, the relationship between the intermediate variable u and the lateral deviation z is set to "(s^2)·z=u." Therefore, when the above equation (c7) is used, the following equation (c9) is established for the intermediate variable.

[0033] u=d(v·sin θ) / dt=(dv / dt)·sin θ+v·cos θ·(dθ·dt) (c9) The above equation (c9) can be transformed into the following equation (c10).

[0034] (dθ·dt)=-(tan θ / v)·(dv / dt)+(1 / v·cos θ)·u...(c10) By substituting the above equation (c10) into the above equation (c8) and replacing the vehicle curvature κ with the target curvature κ*, the above equation (c4) is obtained.

[0035] The correction amount calculation process M34 converts the target curvature κ* into a correction amount Δθp* for the target steering equivalent angle θp*. The correction amount Δθp* may be the value of the steering angle when the curvature of the vehicle's travel path becomes equal to the target curvature κ*.

[0036] The superposition process M36 is a process of substituting a value obtained by adding the correction amount Δθp* to the target steering equivalent angle base value θp*0 for the target steering equivalent angle θp*. The operation signal generation process M38 is a process of generating an operation signal MS for the steering motor 22 based on the target steering equivalent angle θp* as an input variable, and outputting the operation signal MS to the inverter 24.

[0037] The curvature conversion process M40 converts the target steering equivalent angle base value θp*0 as an input variable into a curvature κh. The curvature conversion process M40 is the inverse conversion process of the correction amount calculation process M34.

[0038] The intermediate variable conversion process M42 converts the curvature κh as an input variable into the intermediate variable uh. The intermediate variable conversion process M42 is an inverse conversion process of the linearization process M32. The lateral deviation conversion process M44 substitutes the second-order derivative of the intermediate variable uh as an input variable into the correction amount Δz*.

[0039] The lateral deviation correction process M46 is a process for adding the correction amount Δz* to the target lateral deviation z* and substituting the result for the target lateral deviation z*. The guard process M48 is a process for limiting the magnitude of the target lateral deviation z* to a predetermined value or less. The output variable of the guard process M48 is the target lateral deviation z*, which is an input variable of the deviation calculation process M24.

[0040] "Functions and Effects of the Present Embodiment" The deviation Δz is linearly converted into a closed-loop intermediate variable ufb by the linear conversion process M26. The target lateral deviation z*0 is linearly converted into an open-loop intermediate variable uff by the linear conversion process M28. The intermediate variable u, which is the sum of the closed-loop intermediate variable ufb and the open-loop intermediate variable uff, is converted into a target curvature κ* by the linearization process M32. Then, the target steering equivalent angle base value θp*0 corrected by the correction amount Δθp* corresponding to the target curvature κ* is used as an input variable for steering control of the steered wheels 20.

[0041] Here, since the relationship between the deviation Δz and the target lateral deviation z*0, which are variables related to the lateral deviation z, and the intermediate variable u is linearized, high controllability of the vehicle behavior can be maintained even when traveling on lanes with various curvatures.

[0042] That is, according to the above equations (c5) to (c7), the relationship between the lateral deviation z and the angular deviation θ not only depends on the curvature κ and the trajectory curvature κr, but the relationship itself is nonlinear. Therefore, for example, when the target curvature κ* and the correction amount Δθp* are determined by PID control or the like in which the deviation Δz is an input variable, the control responsiveness varies depending on the curvature of the traveling lane, etc. In contrast, according to this embodiment, the relationship between the variable related to the lateral deviation z and the intermediate variable u is linearized, thereby improving the ability of the actual lateral deviation z to follow the target lateral deviation z*0.

[0043] The above embodiment further provides the following actions and effects: (1) A relationship is established in which the lateral deviation z is equal to the double integral of the intermediate variable u. This allows the relationship between the intermediate variable u and the target curvature κ* to be set to the relationship defined by the above formula (c4).

[0044] (2) The PU 62 sets the operation variable, which is a variable for generating an operation signal for the actuator as a conversion target from the intermediate variable u, to the target curvature κ*. This makes it easy to convert the operation variable into the steering equivalent angle θp.

[0045] (3) The PU 62 converts the target curvature κ* into the correction amount Δθp* of the target steering equivalent angle base value θp*0. This makes it possible to correct the target steering equivalent angle base value θp*0 in accordance with the driver's intention from the perspective of driving assistance.

[0046] (4) PU 62 corrects target lateral deviation z*0, which is the target value of closed-loop control, by correction amount Δz*, which is obtained by converting target steering equivalent angle base value θp*0 into lateral deviation z. This makes it possible to suppress interference with the driver's steering intention in closed-loop control in which lateral deviation z is the controlled variable, compared to closed-loop control in which target lateral deviation z*0 is the controlled variable target value.

[0047] That is, in the case of closed-loop control in which target lateral deviation z*0 is the target value of the controlled variable, a change in target steering equivalent angle base value θp*0 in response to the driver's steering intention is a disturbance element for the closed-loop control. Therefore, closed-loop control in which target lateral deviation z*0 is the target value of the controlled variable interferes with the driver's steering. In contrast, in this embodiment, by correcting target lateral deviation z* with correction amount Δz* that reflects the driver's steering intention, it is possible to prevent the closed-loop control from interfering with the driver's steering.

[0048] (5) The target value of the control amount of the closed-loop control is set to a value obtained by correcting the target lateral deviation z*0 using the correction amount Δz* and then performing the guard process M48 on the corrected value. This prevents the magnitude of the lateral deviation z from being controlled to an excessively large value by the closed-loop control.

[0049] <Other Embodiments> This embodiment can be modified as follows: This embodiment and the following modifications can be combined and implemented within the scope of technical compatibility.

[0050] Regarding the Linear Transformation Process: The response characteristics of the linear transformation process M26 may be changed depending on the vehicle's running state. This can be achieved, for example, by changing the value of the variable ω in the above equation (c1) depending on the running state. Specifically, the PU 62 may change the value of the variable ω depending on the vehicle speed v, for example.

[0051] It is not essential that the linear conversion process M26 be configured by setting the responsiveness of the lateral deviation z relative to the target lateral deviation z* to the responsiveness shown in the above equation (c3). The linear conversion process M26 may be configured, for example, by assuming a first-order lag responsiveness as the responsiveness of the lateral deviation z relative to the target lateral deviation z*.

[0052] The linear transformation process does not necessarily have to be a process of transforming such that the double integral of the intermediate variable is equal to the variable related to the lateral deviation z. Regarding the Linearization Process The target variable as the output variable of the linearization process does not necessarily have to be the target curvature κ*. For example, it may be the target steering equivalent angle θp*.

[0053] The linearization process does not necessarily have to be a process of calculating the target curvature κ* using the above equation (c4). The linearization process may be, for example, a process in which the PU 62 calculates the target curvature κ* from a map stored in the storage device 64. Here, the map data is data in which the intermediate variable u, the vehicle speed v, the angle deviation θ, and the trajectory curvature κr are input variables and the target curvature κ* is an output variable. Here, the speed direction angle θ0 and the trajectory direction angle θr may be used as the traveling direction variable, which is an input variable, instead of the angle deviation θ.

[0054] Note that map data is a set of data consisting of discrete values ​​of input variables and values ​​of output variables corresponding to each of the input variable values. Furthermore, map calculation may be a process in which, when the value of an input variable matches one of the input variable values ​​in the map data, the value of the corresponding output variable in the map data is the calculation result. Furthermore, map calculation may be a process in which, when the value of an input variable does not match any of the input variable values ​​in the map data, the calculation result is a value obtained by interpolating the values ​​of multiple output variables included in the map data. Alternatively, map calculation may be a process in which, when the value of an input variable does not match any of the input variable values ​​in the map data, the calculation result is the value of the output variable in the map data that corresponds to the closest value of the multiple input variables included in the map data.

[0055] Regarding the operation variable: The operation variable for generating the operation signal for the actuator is not limited to the correction amount of the target steering equivalent angle θp*. For example, as described in the section "Regarding the operation processing" below, if the operation processing is processing for operating an actuator for autonomous driving, the operation variable may be the target steering equivalent angle θp*.

[0056] The operation variable for generating the actuator operation signal is not limited to a variable indicating the steering angle of the steered wheels. For example, the operation variable may be a variable that determines the operation amount of a brake actuator. Furthermore, for example, the operation variable may be both a variable that indicates the steering angle of the steered wheels and a variable that determines the operation amount of a brake actuator. In this case, PU 62 may appropriately set the contribution rates of the steering of the steered wheels and the moment realized by the brake actuator in approximating the curvature of the vehicle's traveling trajectory to the target curvature κ*.

[0057] Regarding the Operation Variable Conversion Process: The correction amount calculation process M34 as the operation variable conversion process does not necessarily have to be a process of setting the correction amount Δθp* as the operation amount of open-loop control in which the target curvature κ* is the control amount. For example, the correction amount calculation process M34 may be a process of substituting the operation amount of closed-loop control in which the vehicle curvature κ is the control amount and the target curvature κ* is the target value of the control amount for the correction amount Δθp*. In this case, the PU 62 may change the gain of the closed-loop control in response to the steering by the driver. Specifically, the PU 62 may change the gain in response to the magnitude of the torque input to the steering shaft 14 by the driver, for example.

[0058] Regarding the Target Value Correction Process: The correction amount for correcting the target lateral deviation z*0 does not necessarily have to be the second-order differential value of the intermediate variable uh. The correction amount for correcting the target lateral deviation z*0 may be, for example, a value obtained by performing the inverse transformation process of the linear transformation process M26 on the intermediate variable uh as an input variable.

[0059] "Method for suppressing interference between closed-loop control and driver's steering" The method for suppressing interference between closed-loop control and driver's steering does not necessarily have to be a process for correcting the target value of the control amount in closed-loop control. For example, it may be a method for calculating the target curvature κ* by changing the angle deviation θ in the above equation (c4) as follows. That is, PU 62 calculates the angle deviation θ based on a value obtained by correcting the speed direction angle θ0 in accordance with the rate of change of the target steering equivalent angle base value θp*0. In this case, the change in the target steering equivalent angle θp* due to the driver's steering is reflected in the target curvature κ*, so interference between the closed-loop control and the driver's steering can be suppressed.

[0060] Regarding the controller that controls the trajectory of a vehicle to follow a target trajectory, it is not essential that the controller that controls the trajectory of a vehicle to follow a target trajectory include both a controller for closed-loop control and a controller for open-loop control. For example, the controller may include only one of the two.

[0061] "Regarding the Operation Processing" The operation processing does not necessarily have to be processing for operating an actuator to assist steering by a driver. For example, it may be processing for operating an actuator for automatic driving. In that case, for example, instead of converting the target curvature κ* into the correction amount Δθp* of the target steering equivalent angle θp*, the target curvature κ* may be converted into the target steering equivalent angle θp*.

[0062] Regarding the control device: The steering control device 30 and the ADASECU 60 may be integrated. If the operation variables include a variable that determines the operation amount of the brake actuator, the control device may include a control device whose control target is the brake actuator.

[0063] The vehicle control device is not limited to one that includes a PU and a storage device and executes software processing. For example, it may include a dedicated hardware circuit, such as an ASIC, that executes at least some of the various processes executed in the above embodiments. That is, the control device may include any of the following processing circuits (a) to (c): (a) A processing circuit that includes a processing device that executes all of the above processes according to a program and a program storage device, such as a storage device, that stores the program. (b) A processing circuit that includes a processing device and program storage device that executes some of the above processes according to a program, and a dedicated hardware circuit that executes the remaining processes. (c) A processing circuit that includes a dedicated hardware circuit that executes all of the above processes. Here, there may be multiple software execution devices that include a processing device and a program storage device, and multiple dedicated hardware circuits.

[0064] Regarding the entity that executes the vehicle control method: It is not essential that all of the entities that execute the processes in the above-described embodiment and their modifications are processing circuits mounted on the vehicle.

[0065] "Others" - It is not essential to provide guard processing M48.

Claims

1. A vehicle control device that operates a specified actuator to change the vehicle's driving direction, the vehicle control device being configured to execute a linear transformation process, a linearization process, and an operation process, wherein the linear transformation process is a process of linearly transforming values ​​of input variables into values ​​of intermediate variables, the input variables of the linear transformation process being variables related to control amounts for controlling the vehicle's trajectory to follow a target trajectory, the linearization process is a process of converting values ​​of the intermediate variables into values ​​of target variables based on values ​​of a driving direction variable, vehicle speed, and a trajectory curvature variable as input variables, the driving direction variable being a variable indicating the vehicle's driving direction, the trajectory curvature variable being a variable indicating a curvature related to the target trajectory, and the target variable being a variable indicating a target value for a change in the vehicle's driving direction, and the operation process is a process of operating the actuator based on values ​​of the target variables as input variables.

2. A vehicle control device as described in claim 1, wherein the operation processing includes an operation variable conversion processing and an operation signal generation processing, the operation variable conversion processing is processing for converting the value of the target variable into the value of an operation variable, the operation variable is a variable for generating an operation signal for the actuator, and the operation signal generation processing is processing for generating an operation signal for the actuator based on the value of the operation variable as an input variable.

3. A vehicle control device as described in claim 2, configured to execute a base value setting process and a superimposition process, wherein the base value setting process is a process for calculating a base value of the operation variable based on the rotational operation of the steering shaft by the driver, and the superimposition process is a process for outputting a value obtained by superimposing the value of the output variable of the operation variable conversion process on the base value to the operation signal generation process.

4. A vehicle control device according to claim 3, wherein the input variables of the linear transformation process include a deviation between the controlled variable and its target value.

5. A vehicle control device as described in claim 4, configured to execute a curvature conversion process, an intermediate variable conversion process, a control variable conversion process, and a target value correction process, wherein the curvature conversion process is a process of converting the base value as an input variable into a curvature, the intermediate variable conversion process is a process of converting the curvature converted by the curvature conversion process as an input variable into the value of an intermediate variable, the control variable conversion process is a process of converting the value of the intermediate variable converted by the intermediate variable conversion process as an input variable into the control variable, and the target value correction process is a process of correcting the target value by the control variable converted by the control variable conversion process.

6. A vehicle control device according to claim 5, configured to execute a guard process, wherein the guard process is a process for limiting the target value corrected by the target value correction process to within a predetermined range.

7. A vehicle control device according to claim 4, wherein the control amount is a lateral deviation between the actual trajectory of the vehicle and the target trajectory.

8. The vehicle control device according to claim 1, wherein the actuator is configured to steer steerable wheels.

9. A vehicle control method that operates a predetermined actuator to change the vehicle's traveling direction, the method including the execution of a linear transformation process, a linearization process, and an operation process, wherein the linear transformation process is a process of linearly transforming values ​​of input variables into values ​​of intermediate variables, the input variables of the linear transformation process are variables related to control amounts for controlling the vehicle's trajectory to follow a target trajectory, the linearization process is a process of converting values ​​of the intermediate variables into values ​​of target variables based on values ​​of a traveling direction variable, vehicle speed, and a trajectory curvature variable as input variables, wherein the traveling direction variable is a variable indicating the vehicle's traveling direction, the trajectory curvature variable is a variable indicating curvature related to the target trajectory, and the target variable is a variable indicating a target value for change in the vehicle's traveling direction, and the operation process is a process of operating the actuator based on values ​​of the target variables as input variables.

10. A vehicle control program for operating a specified actuator to change the vehicle's driving direction, the program including instructions to cause a computer to execute linear transformation processing, linearization processing, and operation processing, wherein the linear transformation processing is a processing for linearly transforming values ​​of input variables into values ​​of intermediate variables, the input variables of the linear transformation processing are variables related to control amounts for controlling the vehicle's trajectory to follow a target trajectory, the linearization processing is a processing for converting values ​​of the intermediate variables into values ​​of target variables based on values ​​of a driving direction variable, vehicle speed, and values ​​of a trajectory curvature variable as input variables, the driving direction variable is a variable indicating the vehicle's driving direction, the trajectory curvature variable is a variable indicating curvature related to the target trajectory, and the target variable is a variable indicating a target value for change in the vehicle's driving direction, and the operation processing is a processing for operating the actuator based on values ​​of the target variables as input variables.

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