Vehicle control device

Abstract

The invention relates to a vehicle control apparatus. A vehicle control device according to an embodiment of the present invention causes a vehicle to travel along a target path created by connecting a plurality of types of lines, and is provided with: a target curvature calculation unit; a smoothing target curvature calculation unit that calculates a smoothing target curvature relating to a point to be calculated by calculating a smoothing value of a target curvature of a plurality of points including the point to be calculated and a predetermined number of points before and after the point to be calculated on the target path, any one of the points being a connection point of lines of different types; a target steering angle calculation unit that calculates a target steering angle on the basis of the smoothing target curvature; and a control unit that controls steering on the basis of the target steering angle when the vehicle is driven.

Description

Technical Field

[0001] Embodiments of the present invention relate to a vehicle control device. Background Art

[0002] Conventionally, technology has been developed to allow vehicles to travel along a target path. In this case, the target path is created by connecting multiple types of lines, such as straight lines, circular arcs, and clothoid curves.

[0003] Patent Document 1: Japanese Patent Application Laid-Open No. 2017-30482

[0004] However, in the above-mentioned prior art, when steering control is performed on the connection points of different types of lines on the target path (for example, the connection points of a clothoid curve and a circular arc, etc.), smooth steering control is often not possible due to the step-like change of the target curvature gradient (the first-order differential value of the target curvature), and ride comfort deteriorates. Summary of the Invention

[0005] Therefore, the present invention has been completed in view of the above situation, and an object of the present invention is to provide a vehicle control device that can achieve smooth steering control before and after the connection point of different types of lines on the target path when the vehicle is driven along the target path.

[0006] In order to solve the above-mentioned problems, the vehicle control device of the embodiment is a vehicle control device that causes the vehicle to travel along a target path created by connecting multiple types of lines, and comprises: a target curvature calculation unit, which calculates a smoothed target curvature related to the above-mentioned calculation object location by calculating the smoothed values ​​of the target curvatures of multiple locations on the above-mentioned target path, including the calculation object location and a specified number of locations before and after the location, and any location is a connection point of different types of lines; a target steering angle calculation unit, which calculates a target steering angle based on the above-mentioned smoothed target curvature; and a control unit, which controls steering based on the above-mentioned target steering angle when causing the above-mentioned vehicle to travel.

[0007] According to the above configuration, when the vehicle travels along the target path, steering control is performed using the target steering angle based on the smooth target curvature, thereby achieving smooth steering before and after the connection point of different types of lines on the target path.

[0008] In addition, in the vehicle control device, the target curvature calculation unit calculates the average value of the target curvatures at the plurality of locations, or the weighted average value of the target curvatures obtained by weighting the target curvatures at the plurality of locations and calculating the weighted average value of the target curvatures, as the smoothed target curvature.

[0009] According to the above configuration, steering control using the target steering angle based on the average value or weighted average value of the target curvature can be executed through simple processing.

[0010] In addition, in the vehicle control device, when determining the positions of the above-mentioned multiple locations, the above-mentioned target curvature calculation unit uses the above-mentioned calculation object location as a reference, determines the position of the adjacent location by the distance obtained by multiplying the vehicle speed by a predetermined time, and repeats the calculation to determine the positions of the above-mentioned multiple locations.

[0011] According to the above configuration, specifically, appropriate positions of a plurality of points can be determined.

[0012] Furthermore, in the vehicle control device, the target curvature calculation unit uses a target vehicle speed as the vehicle speed.

[0013] Since the target vehicle speed is more stable than the actual vehicle speed, according to the above configuration, by using the target vehicle speed as the vehicle speed, the calculation result can be made more stable. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 This is an exemplary perspective view showing a state in which a portion of the vehicle interior of the vehicle according to the embodiment is seen through.

[0015] Figure 2 is an exemplary top view (bird's-eye view) of the vehicle according to the embodiment.

[0016] Figure 3 This is a diagram showing an example of an instrument panel of a vehicle according to an embodiment, as viewed from the rear of the vehicle.

[0017] Figure 4 is an exemplary block diagram of the structure of a vehicle control system according to an embodiment.

[0018] Figure 5 This is a functional configuration diagram of the ECU according to the embodiment.

[0019] Figure 6 It is an explanatory diagram of calculation of the average target curvature according to the embodiment.

[0020] Figure 7 Graph showing the temporal changes of target curvature and target curvature gradient in the conventional art.

[0021] Figure 8 Graph showing temporal changes in target curvature and target curvature gradient according to the embodiment.

[0022] Figure 9 This is a flowchart showing the processing of the vehicle control system according to the embodiment. DETAILED DESCRIPTION

[0023] The following describes exemplary embodiments of the present invention. The structures of the embodiments described below, as well as the functions, results, and effects resulting from these structures, are merely examples. The present invention can also be implemented using structures other than those disclosed in the following embodiments, and can provide at least one of the various effects and derivative effects derived from the basic structures.

[0024] The vehicle 1 of this embodiment can be, for example, an automobile driven by an internal combustion engine (not shown), i.e., an internal combustion engine vehicle; an automobile driven by an electric motor (not shown), i.e., an electric vehicle, a fuel cell vehicle, etc.; a hybrid vehicle driven by both of these; or an automobile equipped with other drive sources. Furthermore, the vehicle 1 can be equipped with various transmissions and various devices, such as systems and components, required to drive the internal combustion engine and the electric motor. Furthermore, the type, number, and layout of the devices related to driving the wheels 3 of the vehicle 1 can be variously configured.

[0025] Figure 1 This is an exemplary perspective view showing a state in which a portion of the vehicle interior of the vehicle according to the embodiment is seen through. Figure 2 is an exemplary top view (bird's-eye view) of the vehicle according to the embodiment.

[0026] As in Figure 1 As shown in the figure, the vehicle body 2 constitutes a vehicle cabin 2a in which passengers (not shown) sit. In the vehicle cabin 2a, a steering control unit 4, an accelerator control unit 5, a brake control unit 6, a gear shift control unit 7, etc. are provided in the vehicle cabin 2a in a state facing a driver's seat 2b as a passenger.

[0027] The steering unit 4 is, for example, a steering wheel protruding from the instrument panel 24. The accelerator unit 5 is, for example, an accelerator pedal located under the driver's feet. The brake unit 6 is, for example, a brake pedal located under the driver's feet. The shift unit 7 is, for example, a shift lever protruding from the center console. However, the steering unit 4, accelerator unit 5, brake unit 6, and shift unit 7 are not limited to these.

[0028] In addition, a display device 8 serving as a display output unit and a sound output device 9 serving as a sound output unit are provided in the vehicle interior 2a. The display device 8 is, for example, an LCD (liquid crystal display), an OELD (organic electroluminescent display), or the like. The sound output device 9 is, for example, a speaker. In addition, the display device 8 is covered by a transparent operation input unit 10 such as a touch panel. Passengers can recognize the image displayed on the display screen of the display device 8 via the operation input unit 10. In addition, passengers can 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.

[0029] The display device 8, audio output device 9, and operation input unit 10 are provided, for example, in a monitoring device 11 located in the center of the instrument panel 24 in the vehicle width direction, i.e., in the left-right direction. The monitoring device 11 may include an operation input unit (not shown), such as a switch, knob, joystick, or button. Furthermore, an audio output device (not shown) may be provided at a different location within the vehicle interior 2a than the monitoring device 11. Furthermore, audio can be output from the audio output device 9 of the monitoring device 11 and from other audio output devices. Furthermore, the monitoring device 11 may also function as a navigation system or an audio system, for example.

[0030] In addition, a display device 12 (see FIG. 1 ) is provided in the vehicle interior 2a, which is different from the display device 8. Figure 3 ). Figure 3 FIG. 1 is a diagram showing an example of a vehicle instrument panel according to an embodiment, as viewed from the rear of the vehicle. Figure 3 As shown in the example, the display device 12 is provided on the instrument panel 25 of the instrument panel 24, and is located approximately in the center of the instrument panel 25, between the speed display portion 25a and the rotation speed display portion 25b. The screen size of the display device 12 is smaller than the screen size of the display device 8 ( Figure 1 ) in size. Display device 12 can primarily display images of information related to driving control of vehicle 1 (e.g., parking assist control). The amount of information displayed on display device 12 may be less than that displayed on display device 8. Display device 12 is, for example, an LCD or OLED. Furthermore, information displayed on display device 12 may also be displayed on display device 8.

[0031] In addition, if Figure 1 as well as Figure 2 As shown in the example, the vehicle 1 is a four-wheeled vehicle having two left and right front wheels 3F and two left and right rear wheels 3R. The four wheels 3 are all configured to be steerable.

[0032] Figure 4FIG. 1 is an exemplary block diagram of the structure of a vehicle control system according to an embodiment. Figure 4 As shown, the vehicle 1 has an EPS13 (electric power steering system) for steering at least two wheels 3. The EPS13 has an actuator 13a and a torque sensor 13b. The EPS13 is electrically controlled by an ECU14 (electronic control unit) or the like to operate the actuator 13a. In the following description, the EPS13 is an electric power steering system, an SBW (steer by wire) system, or the like. The EPS13 applies torque, i.e., auxiliary torque, to the steering control unit 4 through the actuator 13a to supplement the steering force, or steers the wheel 3 through the actuator 13a. In this case, the actuator 13a can steer one wheel 3 or multiple wheels 3. In addition, the torque sensor 13b detects, for example, the torque applied by the driver to the steering control unit 4.

[0033] In addition, if Figure 2 As illustrated, as a plurality of photographing units 15, four photographing units 15a to 15d are provided on the vehicle body 2, for example. The photographing unit 15 is, for example, a digital camera with built-in photographing elements such as a CCD (charge coupled device) and a CIS (CMOS image sensor). The photographing unit 15 can output moving image data at a specified frame rate. The photographing unit 15 has a wide-angle lens or a fisheye lens, and can photograph a range of, for example, 140° to 190° in the horizontal direction. In addition, the optical axis of the photographing unit 15 is set to face obliquely downward. Therefore, the photographing unit 15 sequentially photographs the external environment surrounding the vehicle body 2, including the road surface on which the vehicle 1 can move and the area where the vehicle 1 can park, and outputs it as photographed image data.

[0034] The imaging unit 15a is, for example, located at the end 2e on the rear side of the vehicle body 2 and is provided on the wall below the door 2h of the rear trunk. The imaging unit 15b is, for example, located at the end 2f on the right side of the vehicle body 2 and is provided on the right door mirror 2g. The imaging unit 15c is, for example, located at the front side of the vehicle body 2, that is, at the end 2c on the front side in the front-to-rear direction of the vehicle, and is provided on the front bumper, etc. The imaging unit 15d is, for example, located at the left side of the vehicle body 2, that is, at the end 2d on the left side in the vehicle width direction, and is provided on the door mirror 2g which is a protruding portion on the left side. The ECU 14 performs calculation processing and image processing based on the image data obtained by the multiple imaging units 15, and is capable of generating an image with a wider field of view, or generating a virtual bird's-eye view image (top view image) of the vehicle 1 viewed from above.

[0035] Furthermore, the ECU 14 recognizes a dividing line or the like indicated on the road surface around the vehicle 1 from the image of the imaging unit 15 , and detects (extracts) a parking space indicated by the dividing line or the like.

[0036] In addition, if Figure 1 as well as Figure 2 As shown, as a plurality of ranging units 16 and 17, four ranging units 16a to 16d and eight ranging units 17a to 17h are provided on the vehicle body 2, for example. The ranging units 16 and 17 are, for example, sonars that emit ultrasonic waves and capture their reflected waves. Sonars can also be called sonar sensors or ultrasonic detectors. The ECU 14 can use the detection results of the ranging units 16 and 17 to determine the presence of objects such as obstacles around the vehicle 1 and the distance to such objects. In other words, the ranging units 16 and 17 are examples of detection units that detect objects. Furthermore, the ranging unit 17 can be used, for example, to detect objects at relatively close distances, while the ranging unit 16 can be used, for example, to detect objects at relatively long distances that are farther than the ranging unit 17. Furthermore, the ranging unit 17 can be used, for example, to detect objects in front of and behind the vehicle 1, while the ranging unit 16 can be used to detect objects to the sides of the vehicle 1.

[0037] In addition, if Figure 4 As shown, in the vehicle control system 100 that causes the vehicle to travel along a target path, in addition to the ECU 14, the monitoring device 11, the EPS 13, the ranging units 16 and 17, etc., the braking system 18, the steering angle sensor 19, the accelerator sensor 20, the shift sensor 21, the wheel speed sensor 22, etc. are electrically connected via the in-vehicle network 23 which serves as an electrical communication line.

[0038] The in-vehicle network 23 is configured, for example, as a CAN (controller area network). The ECU 14 controls the EPS 13, the brake system 18, and the like by sending control signals via the in-vehicle network 23. Furthermore, the ECU 14 can receive detection results from the torque sensor 13b, the brake sensor 18b, the rotational angle sensor 19, the distance measuring unit 16, the distance measuring unit 17, the accelerator sensor 20, the shift sensor 21, the wheel speed sensor 22, and other sensors, as well as operation signals from the operation input unit 10 and other sensors, via the in-vehicle network 23.

[0039] like Figure 4As shown, the ECU 14 includes, for example, a CPU 14 a (central processing unit), a ROM 14 b (read only memory), a RAM 14 c (random access memory), a display control unit 14 d , a sound control unit 14 e , and an SSD 14 f (solid state drive, flash memory).

[0040] The CPU 14a can perform various computational processes and controls, such as image processing related to images displayed on the display devices 8 and 12, determination of the target position of the vehicle 1, calculation of the movement path of the vehicle 1, determination of the presence or absence of interference with an object, automatic control of the vehicle 1, and release of automatic control. The CPU 14a can read a program installed and stored in a nonvolatile storage device such as the ROM 14b and perform computational processes in accordance with the program.

[0041] The RAM 14c temporarily stores various data used in the calculations of the CPU 14a. Furthermore, the display control unit 14d, within the calculations of the ECU 14, primarily performs image processing using image data obtained by the imaging unit 15 and synthesizes image data displayed on the display devices 8 and 12. Furthermore, the sound control unit 14e, within the calculations of the ECU 14, primarily performs processing of sound data output by the sound output device 9. 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.

[0042] Furthermore, the CPU 14a, ROM 14b, RAM 14c, and the like can be integrated into the same package. Furthermore, the ECU 14 may utilize a DSP (digital signal processor) or other logic processor, logic circuit, or the like in place of the CPU 14a. Furthermore, an HDD (hard disk drive) may be provided in place of the SSD 14f, or the SSD 14f and HDD may be provided separately from the ECU 14.

[0043] The brake system 18 includes, for example, an ABS (anti-lock brake system) that prevents brake lock, an electronic stability control (ESC) system that prevents the vehicle 1 from slipping when turning, an electric brake system that enhances braking force (performs brake assist), or a brake-by-wire (BBW) system. The brake system 18 applies braking force to the wheels 3 and, consequently, to the vehicle 1 via an actuator 18a.

[0044] Furthermore, the brake system 18 can detect brake lock, wheel 3 spin, or signs of side slip based on the rotational difference between the left and right wheels 3, and can perform various controls. The brake sensor 18b is, for example, a sensor that detects the position of the movable portion of the brake operating unit 6. The brake sensor 18b can detect the position of the brake pedal, which is the movable portion of the brake operating unit 6. The brake sensor 18b includes a displacement sensor.

[0045] The rotation angle sensor 19 is a sensor that detects the steering amount of the steering control unit 4, such as a steering wheel. The rotation angle sensor 19 is configured using, for example, a Hall effect element. The ECU 14 obtains information from the rotation angle sensor 19 regarding the driver's steering amount on the steering control unit 4 and the steering amount of each wheel 3 during automatic steering, and performs various control operations. Furthermore, the rotation angle sensor 19 detects the rotation angle of the rotating parts of the steering control unit 4. The rotation angle sensor 19 is an example of an angle sensor.

[0046] The accelerator sensor 20 is a sensor that detects the position of a movable portion of the accelerator operating unit 5. The accelerator sensor 20 can detect the position of an accelerator pedal that is a movable portion of the accelerator operating unit 5. The accelerator sensor 20 includes a displacement sensor.

[0047] The shift sensor 21 is a sensor that detects the position of a movable portion of the shift operating unit 7. The shift sensor 21 can detect the position of a lever, arm, button, or the like, which is a movable portion of the shift operating unit 7. The shift sensor 21 may include a displacement sensor or may be configured as a switch.

[0048] The wheel speed sensor 22 detects the rotational speed of the wheel 3 and the number of revolutions per unit time. The wheel speed sensor 22 outputs the number of wheel speed pulses representing the detected rotational speed as a sensor value. The wheel speed sensor 22 can be configured using, for example, a Hall effect element. The ECU 14 calculates the movement amount of the vehicle 1 and other parameters based on the sensor values ​​obtained from the wheel speed sensor 22 and performs various control operations. The wheel speed sensor 22 may also be included in the brake system 18. In this case, the ECU 14 obtains the detection results of the wheel speed sensor 22 via the brake system 18.

[0049] The structures, arrangements, electrical connection forms, and the like of the various sensors and actuators described above are merely examples, and various settings (changes) are possible.

[0050] In this embodiment, the ECU 14 implements at least a portion of its functions as a vehicle control device through the coordination of hardware and software (control program). The vehicle control device drives the vehicle along a target path created by connecting multiple types of lines. The target path can be created by connecting multiple types of lines, such as straight lines, circular arcs, and clothoid curves.

[0051] Below, refer to Figures 5 to 9 A technique for achieving smooth steering before and after a connection point of different types of lines on a target path when the vehicle 1 is caused to travel along the target path will be described.

[0052] In the present invention, "smoothing" of a predetermined parameter means smoothing the change in the gradient (first-order differential value) of the parameter. Hereinafter, the target curvature when the vehicle is traveling on a curve is used as an example parameter.

[0053] For example, when using a path created by connecting multiple types of lines, such as straight lines, circular arcs, and clothoids, the curvature gradient at the connection points inevitably changes in steps, resulting in a sudden change in curvature. In this case, smoothing the curvature gradient in the interval containing the connection points can smooth the change in curvature gradient.

[0054] In this case, if the vertical axis is set as the target curvature and the horizontal axis is set as time to form a graph, the target curvature curve after smoothing will be in a state of smoothly connecting at the connection points, that is, in a state without sharp corners. Figure 7 、 Figure 8 This will be discussed later.

[0055] Hereinafter, a case where averaging is used as an example of smoothing will be described. However, smoothing is not limited to averaging, and may be performed using other methods.

[0056] Figure 5 14 is a functional configuration diagram of the ECU 14 according to the embodiment. The ECU 14 includes, as a functional configuration, an acquisition unit 141 , a vehicle position estimation unit 142 , an average target curvature calculation unit 143 , a target steering angle calculation unit 144 , and a control unit 145 .

[0057] The acquisition unit 141 acquires various information from various sensors and various storage units.

[0058] The vehicle position estimation unit 142 estimates the current position of the vehicle 1 using the latest position information of the vehicle 1 , the detection results of the wheel speed sensor 22 , and the like.

[0059] Below, also refer to Figure 6 The average target curvature calculation unit 143 will be described. Figure 6This is an explanatory diagram of the calculation of the average target curvature in the embodiment. The average target curvature calculation unit 143 calculates the average target curvature related to the calculation target point (point P6) by calculating the average value of the target curvatures of a plurality of points (points P1 to P11) on the target route, including the calculation target point (point P6) and a predetermined number (10) of points before and after it.

[0060] Specifically, the average target curvature calculation unit 143 sets a forward position at a look-ahead distance (reference numeral D1) from the current position (reference numeral C) of the vehicle 1 as the calculation target point (point P6). The look-ahead distance (reference numeral D1) is set based on the response delay compensation information of the vehicle 1 and the like.

[0061] In addition, when determining the positions of a plurality of points (points P1 to P11), the average target curvature calculation unit 143 determines the position of the adjacent point by multiplying the vehicle speed by a predetermined time (time between points) as a reference to the calculation target point (point P6), and repeats this calculation to determine the positions of the plurality of points (points P1 to P11). In addition, the time between points and the number of points obtained (in Figure 6 In the example, it is 11 points) and is determined based on considerations such as computational cost.

[0062] When the average target curvature is observed in time series, the change (curvature gradient) becomes smooth, thereby also making the steering control smooth and improving the ride comfort (details will be described later).

[0063] In addition, the average target curvature calculation unit 143 can also weight the curvatures of multiple locations including the connection points of lines of different types and a specified number of locations before and after them to appropriately reflect the degree of influence on the target curvature, and then calculate the average target curvature by adopting equal filtering that takes into account the average of the weighted target curvatures, that is, the weighted average value.

[0064] Alternatively, for example, the average target curvature calculation unit 143 may always calculate the average target curvature related to the calculation target point while the vehicle 1 is traveling.

[0065] In addition, for example, the average target curvature calculation unit 143 can also calculate the average target curvature related to the calculation object location only when multiple locations include connection points of different types of lines on the target path (for example, connection points of a spiral curve and an arc, etc.) during the driving of the vehicle 1.

[0066] Furthermore, the average target curvature calculation unit 143 may use the target vehicle speed in addition to the actual vehicle speed as the vehicle speed.

[0067] The target steering angle calculation unit 144 calculates the target steering angle based on the average target curvature calculated by the average target curvature calculation unit 143. Specifically, for example, the target steering angle calculation unit 144 calculates the target steering angle based on the target curvature and a curvature / steering angle mapping table. The curvature / steering angle mapping table is information indicating the relationship between the target curvature and the steering angle corresponding to the target path, and is created in advance.

[0068] The control unit 145 controls the travel of the vehicle 1. When the vehicle 1 is traveled, the control unit 145 controls the steering based on the target steering angle calculated by the target steering angle calculation unit 144.

[0069] In addition, the ECU 14 may include, in addition to the above-mentioned functional components, a target vehicle speed calculation unit, a filter processing unit, a protection processing unit, and the like, for example.

[0070] The target vehicle speed calculation unit calculates the target vehicle speed based on various information such as the target route, the target curvature, and the current vehicle speed.

[0071] The filter processing unit performs averaging processing (low-pass filtering processing) on ​​the target steering angle output from the target steering angle calculation unit 144. This averaging processing removes noise and smoothes the change in the steering angle.

[0072] The protection processing unit performs protection processing on the target steering angle output from the filtering processing unit so as not to exceed a preset maximum steering angle.

[0073] Figure 7 Graphs showing the temporal changes in target curvature and target curvature gradient in conventional technology. (a) is a graph showing target curvature in conventional technology, and (b) is a graph showing target curvature gradient in conventional technology. The horizontal axis represents time.

[0074] At times t1 to t8, corresponding to the connection points of the different types of lines, the target curvature gradient changes in a stepwise manner, as shown in (b). At this time, the target curvature changes abruptly, as shown in (a). Consequently, smooth steering is often not possible before and after the connection points, deteriorating ride comfort.

[0075] on the other hand, Figure 8 Graphs showing temporal changes in target curvature and target curvature gradient according to an embodiment. (a) is a graph showing target curvature according to an embodiment, and (b) is a graph showing target curvature gradient according to an embodiment. The horizontal axis represents time.

[0076] At times t11 to t18, corresponding to the connection point between different types of lines, and before and after them, a smoothing process using the average target curvature is performed within a predetermined interval including the connection point. As a result, as shown in (b), the target curvature gradient changes with an inclination rather than a step-like change. Furthermore, as shown in (a), the change in target curvature is smooth. This enables smooth steering both before and after the connection point, improving ride comfort.

[0077] Figure 9 1 is a flowchart showing the processing of the vehicle control system 100 according to the embodiment. In step S1, the vehicle position estimation unit 142 estimates the current position of the vehicle 1 using the latest position information of the vehicle 1, the detection results of the wheel speed sensor 22, and the like.

[0078] Next, in step S2, the average target curvature calculation unit 143 calculates the target point ( Figure 6 Calculation is performed at location P6).

[0079] Next, in step S3, the average target curvature calculation unit 143 calculates the target path including the calculation target point ( Figure 6 The average target curvature related to the calculation target point (point P6) is calculated by averaging the target curvatures of a plurality of points (points P1 to P11) including a predetermined number of points before and after the point P6.

[0080] Next, in step S4 , the target steering angle calculation unit 144 calculates a target steering angle based on the average target curvature calculated in step S3 .

[0081] Next, in step S5 , the control unit 145 controls the travel of the vehicle 1 based on the target steering angle calculated in step S4 and the like.

[0082] Thus, according to this embodiment, when driving vehicle 1 along a target path, steering control is performed using a target steering angle based on the average target curvature, enabling smooth steering before and after the connection point of different types of lines on the target path. Specifically, while conventional techniques utilize the target curvature of a single point on the target path for steering control, this embodiment utilizes a target curvature calculated from the target curvatures of multiple points on the target path for steering control, enabling smooth steering.

[0083] Furthermore, if steering control using a target steering angle based on an average value or a weighted average value of target curvatures is always performed while the vehicle 1 is traveling, it can be accomplished with a simple process.

[0084] Furthermore, calculation costs can be reduced by executing steering control using a target steering angle based on an average or weighted average of target curvatures only when necessary (i.e., only when multiple locations include connection points of different types of lines on the target path).

[0085] In addition, when determining the positions of a plurality of points, specifically, the above-mentioned calculation method ( Figure 6 ), determine the appropriate locations for multiple locations.

[0086] In addition, since the target speed is more stable than the actual speed, the target speed can be used as the speed when calculating the average target curvature, so the calculation result can be made more stable. Specifically, since the actual speed information contains noise, the forward position ( Figure 6 The forward position (P6) will change forward and backward, but the target speed does not contain noise, so the forward position does not change forward and backward. Therefore, the steering operation becomes smoother.

[0087] Furthermore, the program executed in vehicle 1 may be provided as a computer program product by storing it in an installable or executable format on a computer-readable storage medium such as a CD-ROM, CD-R, memory card, DVD (Digital Versatile Disk), or floppy disk (FD). Alternatively, the program may be stored on a computer connected to a network such as the Internet and provided by downloading it via the network. Alternatively, the program may be provided or distributed via a network such as the Internet.

[0088] While the embodiments of the present invention have been described above, these embodiments are provided as examples and are not intended to limit the scope of the invention. New embodiments may be implemented in various other forms, and various omissions, substitutions, and modifications may be made without departing from the spirit of the invention. Such embodiments and their variations are intended to be within the scope and spirit of the invention, and are encompassed by the invention described in the technical proposal and its equivalents.

[0089] For example, the types of lines used in creating the target path are not limited to straight lines, circular arcs, and clothoid curves, and other types of lines such as elliptical arcs and Nth-order function curves (N: an integer greater than or equal to 2) may also be used.

[0090] In addition, the number of the plurality of locations used for calculation of the average target curvature is not limited to Figure 6 The 11 shown are also possible as long as there is a plurality.

[0091] [Summary of this embodiment]

[0092] This embodiment has at least the following structures.

[0093] The ECU 14 (vehicle control unit) that causes the vehicle 1 to travel along a target path created by connecting multiple types of lines includes: an average target curvature calculation unit 143 (target curvature calculation unit) that calculates a smoothed target curvature related to the calculation object location by calculating the smoothed value of the target curvature of multiple locations on the target path, including the calculation object location and a specified number of locations before and after the calculation object location, and any of the locations is a connection point of different types of lines; a target steering angle calculation unit 144 that calculates a target steering angle based on the smoothed target curvature; and a control unit 145 that controls steering based on the target steering angle when causing the vehicle to travel.

[0094] With this configuration, when the vehicle 1 travels along the target route, steering control is performed using the target steering angle based on the smooth target curvature, thereby enabling smooth steering before and after the connection point of different types of lines on the target route.

[0095] In addition, in this embodiment, the average target curvature calculation unit 143 (target curvature calculation unit) preferably calculates the average value of the target curvatures of multiple locations or the weighted average value of the target curvatures obtained by weighting the target curvatures of multiple locations and calculating the weighted average value of the target curvatures as the smoothed target curvature.

[0096] According to such a configuration, steering control using a target steering angle based on an average value or a weighted average value of target curvatures can be executed through simple processing.

[0097] In addition, in this embodiment, it is preferred that the average target curvature calculation unit 143 (target curvature calculation unit) determines the positions of multiple locations by taking the calculation object location as a reference, determining the position of the distance obtained by multiplying the vehicle speed by a predetermined time as the position of the adjacent location, and repeating the calculation to determine the positions of multiple locations.

[0098] According to such a configuration, specifically, appropriate positions of a plurality of points can be determined.

[0099] In addition, in the present embodiment, it is preferable that the average target curvature calculation unit 143 (target curvature calculation unit) uses the target vehicle speed as the vehicle speed.

[0100] Since the target vehicle speed is more stable than the actual vehicle speed, according to such a configuration, by using the target vehicle speed as the vehicle speed, the calculation result can be made more stable.

[0101] Furthermore, the effects brought about by the dependent items and implementation methods of the technical solutions are additional effects different from the effects brought about by the independent items of the technical solutions.

[0102] Description of Reference Signs

[0103] 1…Vehicle, 10…Operation input unit, 11…Monitoring device, 12…Display device, 13…EPS, 14…ECU, 100…Vehicle control system, 141…Acquisition unit, 142…Vehicle position estimation unit, 143…Average target curvature calculation unit, 144…Target steering angle calculation unit, 145…Control unit.

Claims

1. A vehicle control device that causes a vehicle to travel along a target path created by connecting a plurality of types of lines, comprising: a target curvature calculation unit that calculates a smoothed target curvature related to the target point by calculating smoothed values ​​of the target curvature at a plurality of points on the target path, including the target point and a predetermined number of points before and after the target point, wherein any of the points is a connection point of lines of different types; a target steering angle calculation unit that calculates a target steering angle based on the smooth target curvature; as well as A control unit controls steering based on the target steering angle when driving the vehicle.

2. The vehicle control device according to claim 1, wherein: The target curvature calculation unit calculates, as the smoothed target curvature, an average value of the target curvatures at the plurality of points or a weighted average value of the target curvatures obtained by weighting the target curvatures at the plurality of points and calculating the weighted average value of the target curvatures.

3. The vehicle control device according to claim 2, wherein: When determining the positions of the plurality of locations, the target curvature calculation unit determines the positions of the plurality of locations by taking the calculation target location as a reference, determining the location of the adjacent location by a distance obtained by multiplying the vehicle speed by a predetermined time, and repeating the calculation.

4. The vehicle control device according to claim 3, wherein: The target curvature calculation unit uses a target vehicle speed as the vehicle speed.

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