Vehicle control device

Abstract

A vehicle control device according to an embodiment performs the following processing. When the vehicle is made to travel along a target path, with respect to steering control in the case where the vehicle is made to travel along a curve, feedforward control is performed using a target curvature based on the target path, and feedback control is performed using a lateral deviation and a yaw angle deviation of the vehicle. In this case, smoothing processing for smoothing changes in the lateral direction deviation and the yaw angle deviation is executed, and a target steering angle is calculated using the processing result.

Description

Vehicle control device

[0001] An embodiment of the present invention relates to a vehicle control device.

[0002] Technologies for driving a vehicle along a target route have been developed. In these technologies, steering control for driving a vehicle around a curve involves, for example, feedforward control using a target curvature based on the target route, and feedback control using the lateral and yaw angle deviations of the vehicle.

[0003] In such a technology, in order to prevent unnatural steering control, for example, there is a technology that interrupts feedback control or weakens the feedback gain when there is a large deviation in the coordinate axis of the target parking frame recognized by the vehicle.

[0004] Japanese Patent Application Laid-Open No. 2020-59330

[0005] However, the above-described conventional technology may have the following problems, for example. First, assume that the current estimated position of the vehicle deviates from the target path, and the vehicle is turning by steering control to move toward the target path through feedback control. At this time, the target path may be updated, and the current estimated position of the vehicle may suddenly become on the target path. In this case, the lateral deviation and yaw angle deviation of the vehicle suddenly become zero (or values ​​close to zero), and the feedback control may cause abrupt steering to transition from turning to straight-line movement, which is undesirable in terms of passenger comfort, etc.

[0006] Therefore, the present invention has been made in consideration of the above circumstances, and an object of the present invention is to provide a vehicle control device that can avoid sudden steering even when the lateral deviation and yaw angle deviation of the vehicle suddenly change when the vehicle is traveling along a target route.

[0007] In order to solve the above problem, a vehicle control device according to an embodiment performs, when a vehicle is caused to travel along a target route, feedforward control using a target curvature based on the target route, and feedback control using a lateral deviation and a yaw angle deviation of the vehicle, with respect to steering control when the vehicle is caused to travel around a curve, and includes a vehicle position estimating unit that estimates a current position of the vehicle and outputs vehicle position information, a lateral deviation calculating unit that calculates a lateral deviation, which is the deviation between an actual lateral position of the vehicle and a target lateral position based on the target route, based on the target route and the vehicle position information, and a control unit that receives the lateral deviation and adjusts a change in the lateral deviation. a yaw angle deviation calculation unit that calculates a yaw angle deviation, which is the deviation between the actual yaw angle of the vehicle and a target yaw angle based on the target route, based on the target route and the vehicle position information; a second filter processing unit that receives the yaw angle deviation and performs a second smoothing process to smooth a change in the yaw angle deviation, and outputs a corrected yaw angle deviation; a target steering angle calculation unit that calculates a target steering angle based on the target route, the corrected lateral deviation, and the corrected yaw angle deviation; and a control unit that controls steering based on the target steering angle.

[0008] According to this configuration, when the vehicle is traveling along a target route, sudden steering can be avoided even when the lateral deviation and yaw angle deviation of the vehicle suddenly change.

[0009] FIG. 1 is an exemplary perspective view showing a state in which a portion of a cabin of a vehicle of an embodiment is seen through. FIG. 2 is an exemplary plan view (bird's-eye view) of the vehicle of an embodiment. FIG. 3 is a view of an example of a dashboard of the vehicle of an embodiment as viewed from behind the vehicle. FIG. 4 is an exemplary block diagram of the configuration of a vehicle control system of an embodiment. FIG. 5 is a steering control block diagram of an embodiment. FIG. 6 is an explanatory diagram regarding updating of a target route in an embodiment. FIG. 7 is a graph showing an example of the time progression of each piece of information in an embodiment. FIG. 8 is a flowchart showing processing regarding steering control in an embodiment.

[0010] Exemplary embodiments of the present invention are disclosed below. The configurations of the embodiments described below, as well as the actions, results, and advantages brought about by the configurations, are examples. The present invention can be realized with configurations other than those disclosed in the following embodiments, and it is possible to obtain at least one of various advantages based on the basic configurations and derivative advantages.

[0011] The vehicle 1 of this embodiment may be, for example, an automobile using an internal combustion engine (not shown) as a power source, i.e., an internal combustion engine automobile, or an automobile using an electric motor (not shown) as a power source, i.e., an electric automobile or a fuel cell automobile, or a hybrid automobile using both of these as a power source, or an automobile equipped with another power source. The vehicle 1 may be equipped with various transmissions and various devices, such as systems and components, necessary for driving the internal combustion engine or the electric motor. The type, number, layout, etc. of the devices related to driving the wheels 3 of the vehicle 1 may be variously configured.

[0012] Fig. 1 is an exemplary perspective view showing a state in which a part of a vehicle interior of a vehicle according to an embodiment is seen through, and Fig. 2 is an exemplary plan view (bird's-eye view) of the vehicle according to an embodiment.

[0013] 1, a vehicle body 2 forms a cabin 2a in which an occupant (not shown) rides. A steering unit 4, an acceleration operation unit 5, a braking operation unit 6, a gear change operation unit 7, etc. are provided in the cabin 2a, facing a driver's seat 2b as an occupant.

[0014] The steering unit 4 is, for example, a steering wheel protruding from the dashboard 24. The acceleration operation unit 5 is, for example, an accelerator pedal located under the driver's feet. The braking operation unit 6 is, for example, a brake pedal located under the driver's feet. The gear change operation unit 7 is, for example, a shift lever protruding from the center console. Note that the steering unit 4, acceleration operation unit 5, braking operation unit 6, and gear change operation unit 7 are not limited to these.

[0015] A display device 8 serving as a display output unit and an audio output device 9 serving as an audio output unit are also provided within the vehicle interior 2a. The display device 8 is, for example, a liquid crystal display (LCD) or an organic electroluminescent display (OELD). The audio output device 9 is, for example, a speaker. The display device 8 is covered with a transparent operation input unit 10 such as a touch panel. The occupant can visually recognize an image displayed on the display screen of the display device 8 via the operation input unit 10. The occupant can also perform operation input by touching, pressing, or moving the operation input unit 10 with a finger or the like at a position corresponding to the image displayed on the display screen of the display device 8.

[0016] The display device 8, audio output device 9, operation input unit 10, etc. are provided on a monitor device 11, for example, located in the center of the dashboard 24 in the vehicle width direction, i.e., the left-right direction. The monitor device 11 may have an operation input unit (not shown), such as a switch, a dial, a joystick, or a push button. An audio output device (not shown) may be provided in a different position in the vehicle compartment 2a from the monitor device 11. Audio can be output from the audio output device 9 of the monitor device 11 and another audio output device. The monitor device 11 may also be used as, for example, a navigation system or an audio system.

[0017] A display device 12 (see FIG. 3 ), separate from the display device 8, is also provided within the passenger compartment 2a. FIG. 3 is a view of an example of a dashboard of the vehicle of the embodiment, viewed from the rear of the vehicle. As illustrated in FIG. 3 , the display device 12 is provided, for example, in the instrument panel 25 of the dashboard 24, and is positioned approximately in the center of the instrument panel 25, between the speed display unit 25a and the RPM display unit 25b. The screen size of the display device 12 is smaller than the screen size of the display device 8 ( FIG. 1 ). The display device 12 may display images that mainly show information related to driving control (e.g., parking assist control) of the vehicle 1. The amount of information displayed by the display device 12 may be less than the amount of information displayed by the display device 8. The display device 12 may be, for example, an LCD, an OELD, or the like. Note that the information displayed by the display device 12 may also be displayed on the display device 8.

[0018] 1 and 2, the vehicle 1 is, for example, a four-wheeled vehicle, and has two front wheels 3F and two rear wheels 3R. All four wheels 3 can be configured to be steerable.

[0019] FIG. 4 is an exemplary block diagram of a vehicle control system according to an embodiment. As illustrated in FIG. 4 , the vehicle 1 includes an EPS (electric power steering system) 13 that steers at least two wheels 3. The EPS 13 includes an actuator 13a and a torque sensor 13b. The EPS 13 is electrically controlled by an ECU (electronic control unit) 14 or the like to operate the actuator 13a. In the following description, the EPS 13 may be an electric power steering system, a steer-by-wire (SBW) system, or the like. The EPS 13 applies torque, i.e., assist torque, to the steering unit 4 via the actuator 13a to supplement steering force, or steers the wheels 3 via the actuator 13a. In this case, the actuator 13a may steer one wheel 3 or multiple wheels 3. The torque sensor 13b detects, for example, the torque applied by the driver to the steering unit 4.

[0020] 2, the vehicle body 2 is provided with a plurality of imaging units 15, for example, four imaging units 15a to 15d. The imaging units 15 are, for example, digital cameras incorporating imaging elements such as a charge coupled device (CCD) or a CMOS image sensor (CIS). The imaging units 15 can output video data at a predetermined frame rate.

[0021] 1 and 2, the vehicle body 2 is provided with a plurality of distance measuring units 16, 17, for example, four distance measuring units 16a to 16d and eight distance measuring units 17a to 17h. The distance measuring units 16, 17 are, for example, sonars that emit ultrasonic waves and capture the reflected waves. Sonars may also be referred to as sonar sensors or ultrasonic detectors. Based on the detection results of the distance measuring units 16, 17, the ECU 14 can determine the presence or absence of objects, such as obstacles, positioned around the vehicle 1 and the distance to the objects.

[0022] In addition, as illustrated in Figure 4, in a vehicle control system 100 that drives a vehicle along a target route, in addition to the ECU 14, monitor device 11, EPS 13, distance measurement units 16 and 17, etc., a brake system 18, a steering angle sensor 19, an accelerator sensor 20, a shift sensor 21, a wheel speed sensor 22, etc. are electrically connected via an in-vehicle network 23 as an electrical communication line.

[0023] The in-vehicle network 23 is configured as, for example, a CAN (controller area network). The ECU 14 can control the EPS 13, the brake system 18, etc. by sending control signals via the in-vehicle network 23. The ECU 14 can also receive detection results from the torque sensor 13b, the brake sensor 18b, the steering angle sensor 19, the distance measurement unit 16, the distance measurement unit 17, the accelerator sensor 20, the shift sensor 21, the wheel speed sensor 22, etc., as well as operation signals from the operation input unit 10, etc., via the in-vehicle network 23.

[0024] As shown in FIG. 4, the ECU 14 includes, for example, a central processing unit (CPU) 14a, a read only memory (ROM) 14b, a random access memory (RAM) 14c, a display control unit 14d, an audio control unit 14e, and a solid state drive (SSD) 14f (flash memory).

[0025] The CPU 14a can execute various types of arithmetic processing and control, such as image processing related to images displayed on the display devices 8 and 12, determining a target position for the vehicle 1, calculating the path of the vehicle 1, determining whether or not there is interference with an object, and automatically controlling and canceling automatic control of the vehicle 1. The CPU 14a can read out programs installed and stored in a non-volatile storage device such as the ROM 14b, and execute arithmetic processing in accordance with the programs.

[0026] The RAM 14c temporarily stores various data used in the calculations performed by the CPU 14a. The display control unit 14d mainly performs image processing using image data obtained by the imaging unit 15 and synthesis of image data displayed on the display devices 8 and 12, among the calculations performed by the ECU 14. The audio control unit 14e mainly processes audio data output by the audio output device 9, among the calculations performed by the ECU 14. The SSD 14f is a rewritable non-volatile storage unit that can store data even when the power to the ECU 14 is turned off.

[0027] The CPU 14a, ROM 14b, RAM 14c, etc. may be integrated in the same package. The ECU 14 may be configured to use other logic operation processors, such as a DSP (digital signal processor), or logic circuits instead of the CPU 14a. The SSD 14f may be replaced with a HDD (hard disk drive), or the SSD 14f and HDD may be provided separately from the ECU 14.

[0028] The brake system 18 is, for example, an anti-lock brake system (ABS) that prevents the brakes from locking, an electronic stability control (ESC) that prevents the vehicle 1 from skidding when cornering, an electric brake system that increases the braking force (performing brake assist), a brake-by-wire (BBW), etc. The brake system 18 applies a braking force to the wheels 3 and thus to the vehicle 1 via an actuator 18 a.

[0029] The brake system 18 can also detect signs of brake lock, wheel spinning, skidding, etc. from the rotational difference between the left and right wheels 3, and execute various controls. The brake sensor 18b is, for example, a sensor that detects the position of a movable part of the brake operating unit 6. The brake sensor 18b can detect the position of a brake pedal, which is a movable part of the brake operating unit 6. The brake sensor 18b includes a displacement sensor.

[0030] The steering angle sensor 19 is a sensor that detects the amount of steering of the steering unit 4, such as a steering wheel. The steering angle sensor 19 is configured using, for example, a Hall element. The ECU 14 acquires the amount of steering of the steering unit 4 by the driver, the amount of steering of each wheel 3 during automatic steering, etc. from the steering angle sensor 19 and performs various controls. The steering angle sensor 19 detects the rotation angle of a rotating part included in the steering unit 4.

[0031] The accelerator sensor 20 is, for example, a sensor that detects the position of a movable part of the acceleration operation unit 5. The accelerator sensor 20 can detect the position of an accelerator pedal as a movable part of the acceleration operation unit 5. The accelerator sensor 20 includes a displacement sensor.

[0032] The shift sensor 21 is, for example, a sensor that detects the position of a movable part of the gearshift operating unit 7. The shift sensor 21 can detect the position of a lever, arm, button, etc., which are movable parts of the gearshift operating unit 7. The shift sensor 21 may include a displacement sensor, or may be configured as a switch.

[0033] The wheel speed sensor 22 is a sensor that detects the amount of rotation of the wheel 3 and the number of rotations per unit time. The wheel speed sensor 22 outputs the number of wheel speed pulses indicating the detected number of rotations as a sensor value. The wheel speed sensor 22 may be configured using, for example, a Hall element. The ECU 14 calculates the amount of movement of the vehicle 1 based on the sensor value acquired from the wheel speed sensor 22 and executes various controls. Note that the wheel speed sensor 22 may be provided in the brake system 18. In this case, the ECU 14 acquires the detection result of the wheel speed sensor 22 via the brake system 18.

[0034] The configurations, arrangements, electrical connection forms, etc. of the various sensors and actuators described above are merely examples, and can be set (changed) in various ways.

[0035] In this embodiment, the ECU 14 realizes at least a part of the functions as a vehicle control device through cooperation between hardware and software (control program). When the vehicle 1 is caused to travel along a target route, the ECU 14 performs feedforward control using a target curvature based on the target route, and feedback control using the lateral deviation and yaw angle deviation of the vehicle, with respect to steering control when the vehicle 1 is caused to travel around a curve.

[0036] The following description will be continued with reference to Figures 5 and 6. Figure 5 is a steering control block diagram in this embodiment. Figure 6 is an explanatory diagram relating to updating of the target path in this embodiment.

[0037] As shown in Figure 6(a), the current estimated position of vehicle 1 may deviate from the target route R1, causing lateral and yaw angle deviations in vehicle 1, and steering control may be performed to turn vehicle 1 to move it toward the target route using feedback control.

[0038] At that time, the target route is updated, and the current estimated position of the vehicle 1 may suddenly become on the target route R2, as shown in FIG. 6B. In that case, the lateral deviation and yaw angle deviation of the vehicle 1 suddenly become 0 (or values ​​close to 0) (i.e., change suddenly), and the feedback control causes sudden steering to transition from turning to straight-line movement, which is undesirable in terms of passenger comfort, etc. Therefore, hereinafter, a technique will be described that can avoid sudden steering even when the lateral deviation and yaw angle deviation of the vehicle 1 suddenly change when the vehicle 1 is traveling along the target route.

[0039] The units 201 to 209, 221, and 222 shown in FIG. 5 are realized as functions of the ECU 14 (FIG. 4), for example.

[0040] The vehicle position estimation unit 201 estimates the current position of the vehicle 1 using the latest position information of the vehicle 1 and the detection results of the wheel speed sensor 22, and outputs vehicle position information.

[0041] Further, the deviation calculation unit 202 (lateral deviation calculation unit) calculates the lateral deviation, which is the deviation between the actual lateral position of the vehicle 1 and the target lateral position based on the target route, based on the target route and vehicle position information.

[0042] The deviation calculation unit 202 (yaw angle deviation calculation unit) calculates a yaw angle deviation, which is the deviation between the actual yaw angle of the vehicle 1 and the target yaw angle based on the target route, based on the target route and vehicle position information.

[0043] The first filter processing unit 221 receives the lateral deviation from the deviation calculation unit 202 (lateral deviation calculation unit), performs a first smoothing process to smooth the change in the lateral deviation, and outputs the corrected lateral deviation. The first smoothing process may, for example, use the previous value and the current value of the lateral deviation to perform a predetermined calculation to bring the current value closer to the previous value. Specifically, for example, the previous value may be added with {a value obtained by subtracting the previous value from the current value and multiplying it by a predetermined coefficient}. However, this is not limiting, and other calculation methods may also be used. The same applies to the second smoothing process described below. By performing the smoothing process (low-pass filter processing), minute changes due to noise are removed, resulting in a smoother change in the steering angle.

[0044] Furthermore, for example, when the target route is updated (FIG. 6(a) → FIG. 6(b)), the first filter processing unit 221 starts the first smoothing process and executes the first smoothing process until the corrected lateral deviation converges (for example, until it becomes equal to or less than a predetermined lateral deviation threshold value).

[0045] The second filter processing unit 222 receives the yaw angle deviation from the deviation calculation unit 202 (yaw angle deviation calculation unit), performs a second smoothing process to smooth the change in the yaw angle deviation, and outputs the corrected yaw angle deviation. For example, when the target route is updated, the second filter processing unit 222 starts the second smoothing process and performs the second smoothing process until the corrected yaw angle deviation converges (for example, until it becomes equal to or less than a predetermined yaw angle deviation threshold).

[0046] The multiplication unit 203 multiplies the corrected lateral deviation output from the first filtering unit 221 by a gain Ke.

[0047] The multiplier 204 multiplies the corrected yaw angle deviation output from the second filter processor 222 by a gain Kθ.

[0048] The adder 205 adds the value output from the multiplier 203 and the value output from the multiplier 204 together.

[0049] The adding / subtracting unit 206 adds the input target curvature (target curvature based on the target path) and subtracts the value output from the adding unit 205 .

[0050] Target steering angle calculation unit 207 calculates a target steering angle based on a target curvature based on the target route, a corrected lateral deviation (a lateral deviation if the first smoothing process by first filter processing unit 221 is not performed), and a corrected yaw angle deviation (a yaw angle deviation if the second smoothing process by second filter processing unit 222 is not performed). Specifically, target steering angle calculation unit 207 calculates the target steering angle based on the target curvature output from addition / subtraction unit 206 and a curvature / steering angle map 2071. Curvature / steering angle map 2071 is information indicating the relationship between the target curvature and the steering angle.

[0051] The third filter processing unit 208 performs a smoothing process (low-pass filter process) on the target steering angle calculated by the target steering angle calculation unit 207. This smoothing process removes minute changes due to noise, making the steering angle change smoother.

[0052] The guard processing unit 209 performs a guard process on the target steering angle smoothed by the third filtering unit 208 so that the target steering angle does not exceed a preset maximum steering angle.

[0053] When the vehicle 1 is driven, the ECU 14 (controller) uses the EPS 13 to control the steering based on the target steering angle output from the guard processor 209 .

[0054] 7A and 7B are graphs showing examples of the time progression of each piece of information in the embodiment. Note that each graph in FIG. 7 shows a rough change state and is not necessarily strictly accurate. (a) is a route update flag G1, which is "0" when the target route has not been updated and becomes "1" only immediately after the target route has been updated.

[0055] (b) shows the lateral deviation and the yaw angle deviation, where G11 is the case of the prior art and G12 is the case of this embodiment.

[0056] (c) is the target curvature, symbol G20 is the value under FF control (the value added by the addition / subtraction unit 206 in Figure 5), symbol G21 is the value under FB control in the case of conventional technology (the value subtracted by the addition / subtraction unit 206 in Figure 5), and symbol G22 is the value under FB control in the case of this embodiment (the value subtracted by the addition / subtraction unit 206 in Figure 5).

[0057] (d) is the target steering angle, where symbol G31 is for the prior art and symbol G32 is for the present embodiment.

[0058] In the case of the conventional technology, immediately after the target path is updated (from FIG. 6(a) to FIG. 6(b)) and the path update flag is set to "1" (FIG. 7(a)), the lateral deviation and yaw angle deviation suddenly become 0 (or a value close to 0) (reference symbol G11 in FIG. 7(b)). Therefore, the target curvature in the feedback control (the value subtracted by the adding / subtracting unit 206 in FIG. 5) increases rapidly (reference symbol G21 in FIG. 7(c)), and the target steering angle also increases rapidly (reference symbol G31 in FIG. 7(d)), resulting in abrupt steering.

[0059] On the other hand, in this embodiment, after the target path is updated (FIG. 6(a) → FIG. 6(b)) and the path update flag becomes "1" (FIG. 7(a)), the lateral deviation and yaw angle deviation gradually decrease (symbol G12 in FIG. 7(b)) due to the effects of the first smoothing process by the first filter processor 221 and the second smoothing process by the second filter processor 222. Therefore, the target curvature in the FB control (the value subtracted by the adding / subtracting unit 206 in FIG. 5) gradually increases (symbol G22 in FIG. 7(c)), and the target steering angle also gradually increases (symbol G32 in FIG. 7(d)), preventing sudden steering.

[0060] 8 is a flowchart showing a process related to steering control in this embodiment. Here, it is assumed that a target route is given and steering control is being executed by the ECU 14. The process in FIG. 8 is performed periodically.

[0061] In step S1, the vehicle position estimation unit 201 estimates the current position of the vehicle 1 using the latest position information of the vehicle 1 and the detection results of the wheel speed sensor 22, and outputs vehicle position information.

[0062] Next, in step S2, the deviation calculation unit 202 (lateral deviation calculation unit) calculates the lateral deviation based on the target route and vehicle position information.

[0063] Next, in step S3, the deviation calculation unit 202 (yaw angle deviation calculation unit) calculates the yaw angle deviation based on the target route and vehicle position information.

[0064] Next, in step S4, the ECU 14 determines whether the target route has been updated. If Yes, the ECU 14 proceeds to step S5, and if No, the ECU 14 skips step S5.

[0065] In step S5, the ECU 14 turns on the execution flags for the first smoothing process and the second smoothing process. After that, the processes of steps S6 to S9 and the processes of steps S10 to S13 are executed in parallel.

[0066] In step S6, the first filter processing unit 221 determines whether the corrected lateral deviation has converged, and if Yes, the process proceeds to step S7, and if No, the process proceeds to step S8.

[0067] In step S7, the ECU 14 turns off the execution flag for the first smoothing process.

[0068] In step S8, the ECU 14 determines whether the execution flag for the first smoothing process is set (i.e., ON) or not, and if Yes, proceeds to step S9, and if No, proceeds to step S14.

[0069] In step S9, the first filter processing unit 221 receives the lateral deviation calculated in step S2, performs a first smoothing process, and outputs the corrected lateral deviation. Note that if step S9 is not performed, the lateral deviation calculated in step S2 is input to the multiplication unit 203.

[0070] In step S10, the second filter processing unit 222 determines whether the corrected yaw angle deviation has converged. If the result is Yes, the process proceeds to step S11, and if the result is No, the process proceeds to step S12.

[0071] In step S11, the ECU 14 turns off the execution flag for the second smoothing process.

[0072] In step S12, the ECU 14 determines whether the execution flag for the second smoothing process is set (i.e., ON) or not, and if Yes, proceeds to step S13, and if No, proceeds to step S14.

[0073] In step S13, the second filter processing unit 222 receives the yaw angle deviation calculated in step S3, performs a second smoothing process, and outputs the corrected yaw angle deviation. Note that if step S13 is not performed, the yaw angle deviation calculated in step S3 is input to the multiplication unit 204.

[0074] Thereafter, the multiplication unit 203, the multiplication unit 204, the addition unit 205, and the addition / subtraction unit 206 in FIG. 5 perform the respective calculations.

[0075] Next, in step S14 , the target steering angle calculation unit 207 calculates the target steering angle based on the target curvature output from the addition / subtraction unit 206 and the curvature / steering angle map 2071 .

[0076] Next, in step S15, the third filter processing unit 208 performs smoothing processing (low-pass filtering processing) on ​​the target steering angle calculated in step S14.

[0077] Next, in step S16, the guard processing unit 209 performs guard processing on the target steering angle processed in step S15.

[0078] Next, in step S17, the ECU 14 (controller) uses the EPS 13 to control the steering based on the target steering angle processed in step S16.

[0079] As described above, according to the vehicle 1 of this embodiment, when the vehicle 1 is traveling along a target route, even if the lateral deviation and yaw angle deviation of the vehicle 1 suddenly change, sudden steering can be avoided by the action (respective smoothing processes) of the first filter processing unit 221 and the second filter processing unit 222. This allows for natural steering, improving the ride comfort for the occupants and increasing the sense of security for the occupants.

[0080] In addition, as a specific application scenario, when the target route is updated (Figure 6(a) → Figure 6(b)), sudden steering can be avoided by performing smoothing processing using the first filter processing unit 221 and the second filter processing unit 222.

[0081] However, the application scenario is not limited to this. For example, the steering control may be initiated when the position of the vehicle 1 indicated by the vehicle position information estimated by the vehicle position estimation unit 201 deviates from the target route. In this case, in the prior art, sudden steering may occur immediately after the steering control is initiated. On the other hand, according to this embodiment, sudden steering can be avoided by performing smoothing processes by the first filter processing unit 221 and the second filter processing unit 222, as in the case of updating the target route. In this case, the first filter processing unit 221 performs the first smoothing process until the corrected lateral deviation converges, and the second filter processing unit 222 performs the second smoothing process until the corrected yaw angle deviation converges.

[0082] The program executed in the vehicle 1 may be provided as a computer program product stored in an installable or executable file format on a computer-readable storage medium such as a CD-ROM, CD-R, memory card, DVD (Digital Versatile Disk), or flexible disk (FD). Alternatively, the program may be stored on a computer connected to a network such as the Internet and provided by being downloaded via the network. Alternatively, the program may be provided or distributed via a network such as the Internet.

[0083] Although the embodiments of the present invention have been described above, the above embodiments are presented as examples and are not intended to limit the scope of the invention. This novel embodiment can be embodied in various other forms, and various omissions, substitutions, and modifications can be made without departing from the spirit of the invention. This embodiment and its modifications are included within the scope and spirit of the invention, and are also included in the inventions and their equivalents as set forth in the claims.

[0084] [Summary of the Present Embodiment] The present embodiment has at least the following configuration.

[0085] A vehicle control device performs feedforward control using a target curvature based on a target route and feedback control using a lateral deviation and a yaw angle deviation of the vehicle with respect to steering control when the vehicle is caused to travel along a target route, and includes a vehicle position estimating unit that estimates a current position of the vehicle and outputs vehicle position information, a lateral deviation calculating unit that calculates a lateral deviation, which is the deviation between an actual lateral position of the vehicle and a target lateral position based on the target route, based on the target route and the vehicle position information, and a first smoothing process that inputs the lateral deviation and smooths changes in the lateral deviation. a yaw angle deviation calculation unit that calculates a yaw angle deviation, which is the deviation between the actual yaw angle of the vehicle and a target yaw angle based on the target route, based on the target route and the vehicle position information; a second filter processing unit that receives the yaw angle deviation, performs a second smoothing process to smooth a change in the yaw angle deviation, and outputs a corrected yaw angle deviation; a target steering angle calculation unit that calculates a target steering angle based on a target curvature based on the target route, the corrected lateral deviation, and the corrected yaw angle deviation; and a control unit that controls steering based on the target steering angle.

[0086] With this configuration, when the vehicle is traveling along a target route, even if the lateral deviation and yaw angle deviation of the vehicle suddenly change, sudden steering can be avoided by the smoothing processes of the first filter processing unit and the second filter processing unit.

[0087] Furthermore, when the target route is updated, the first filter processing unit starts the first smoothing process and executes the first smoothing process until the corrected lateral deviation converges, and the second filter processing unit starts the second smoothing process and executes the second smoothing process until the corrected yaw angle deviation converges.

[0088] With this configuration, when the target route is updated, the first filter processing unit and the second filter processing unit perform smoothing processing, thereby making it possible to avoid sudden steering.

[0089] Furthermore, if the steering control is initiated when the vehicle position indicated by the vehicle position information deviates from the target route, the first filter processing unit starts the first smoothing process and executes the first smoothing process until the corrected lateral deviation converges, and the second filter processing unit starts the second smoothing process and executes the second smoothing process until the corrected yaw angle deviation converges.

[0090] With this configuration, even if steering control is initiated when the vehicle position indicated by the estimated vehicle position information deviates from the target route, sudden steering can be avoided by performing smoothing processing using the first filter processing unit and the second filter processing unit.

[0091] The effects of the dependent claims and embodiments are additional effects that are different from the effects of the independent claims.

[0092] REFERENCE SIGNS LIST 1... vehicle, 14... ECU, 201... vehicle position estimation unit, 202... deviation calculation unit, 207... target steering angle calculation unit, 221... first filter processing unit, 222... second filter processing unit

Claims

1. A vehicle control device for steering control when a vehicle is traveling along a target route, which performs feedforward control using a target curvature based on the target route and feedback control using a lateral deviation and yaw angle deviation of the vehicle, comprising: a vehicle position estimating unit that estimates the current position of the vehicle and outputs vehicle position information; a lateral deviation calculating unit that calculates a lateral deviation, which is the deviation between an actual lateral position of the vehicle and a target lateral position based on the target route, based on the target route and the vehicle position information; a first filtering unit that inputs the lateral deviation and performs a first smoothing process to smooth changes in the lateral deviation and outputs a corrected lateral deviation; a yaw angle deviation calculating unit that calculates a yaw angle deviation, which is the deviation between the actual yaw angle of the vehicle and a target yaw angle based on the target route, based on the target route and the vehicle position information; and a second filtering unit that inputs the yaw angle deviation and performs a second smoothing process to smooth changes in the yaw angle deviation and outputs a corrected yaw angle deviation. a target steering angle calculation unit that calculates a target steering angle based on a target curvature based on the target route, the corrected lateral deviation, and the corrected yaw angle deviation; and a control unit that controls steering based on the target steering angle.

2. A vehicle control device as described in claim 1, wherein, when the target route is updated, the first filter processing unit starts the first smoothing process and executes the first smoothing process until the corrected lateral deviation converges, and the second filter processing unit starts the second smoothing process and executes the second smoothing process until the corrected yaw angle deviation converges.

3. A vehicle control device as described in claim 1, wherein, when the steering control is initiated when the vehicle position indicated by the vehicle position information deviates from the target route, the first filter processing unit initiates the first smoothing process and executes the first smoothing process until the corrected lateral deviation converges, and the second filter processing unit initiates the second smoothing process and executes the second smoothing process until the corrected yaw angle deviation converges.

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