Vehicle control device

Abstract

To provide a vehicle control device capable of improving safety of a vehicle.SOLUTION: A vehicle control device comprises a target speed calculation section 126 which calculates a target speed of a vehicle. The target speed calculation section 126 has a first speed calculation section 126a, a second speed calculation section 126b, and a target speed setting section 126f. The first speed calculation section 126a calculates, using a route length of a target route to an external edge of a sensing range of an external sensor of the vehicle and a friction coefficient of a road surface, a first speed enabling the vehicle to be stopped at a stop position short of the external edge. The second speed calculation section 126b calculates, using a curvature radius of the target route of the vehicle and the friction coefficient, a second speed enabling the vehicle to follow the target route. The target speed setting section 126f sets a target speed by selecting either the first speed or the second speed whichever is smaller.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to a vehicle control device. [Background technology]

[0002] There is a known invention relating to a technique for controlling vehicle speed when traveling around a curve (see Patent Document 1 below). The cruise control device described in Patent Document 1 includes a first vehicle speed setting unit, a second vehicle speed setting unit, a target setting unit, and a vehicle speed control unit (claim 1, paragraph 0007 of the same document).

[0003] The first vehicle speed setting unit sets a first vehicle speed range in which the frictional force that the host vehicle receives when traveling around a curve in the opposite direction to the centrifugal force is greater than the centrifugal force that the host vehicle receives when traveling around the curve. The second vehicle speed setting unit sets a second vehicle speed range using a contact point between the outer tire of the host vehicle and the road surface of the curve as a rotation axis. In this second vehicle speed range, when traveling around the curve, a second moment acting around the rotation axis due to the weight of the host vehicle is greater than a first moment acting around the rotation axis due to the centrifugal force (ibid., claim 1, paragraph 0008).

[0004] A target setting unit sets a target vehicle speed of the host vehicle within a target vehicle speed range that satisfies both the first vehicle speed range and the second vehicle speed range. A vehicle speed control unit causes the host vehicle to travel at the target vehicle speed set by the target setting unit when the host vehicle travels around the curve (Claim 1, paragraph 0009).

[0005] This configuration makes it possible to prevent the vehicle from skidding when traveling around a curve because the centrifugal force becomes larger than the frictional force, and also to prevent the vehicle from leaning to the outside of the curve because the first moment acting around the axis of rotation due to the centrifugal force becomes larger than the second moment acting around the axis of rotation due to the weight of the vehicle (Ibid., paragraph 0010).

[0006] Also, an intelligent pedal with a car navigation cooperation function is known that supports the driver's deceleration operation according to the size of the corner and the vehicle speed when entering a corner (see Non-Patent Document 1 below, "System Overview"). This system includes a car navigation system, a brake actuator, an active accelerator pedal, and a controller (see Non-Patent Document 1, "System Configuration"). [Prior art documents] [Patent documents]

[0007] [Patent Document 1] JP 2017-100653 A [Non-patent literature]

[0008] [Non-Patent Document 1] Nissan Motor Co., Ltd., "Intelligent pedal with car navigation coordination function", [online], [searched on December 17, 2020], Internet,<URL: https: / / www.nissan-global.com / JP / TECHNOLOGY / OVERVIEW / ndca.html> Summary of the Invention [Problem to be solved by the invention]

[0009] In the above-described conventional technology, for example, while the vehicle is traveling along a target route that includes a curve, there is a risk that the safety of the vehicle may be reduced due to an obstacle that cannot be detected by an external sensor mounted on the vehicle.

[0010] The present disclosure provides a vehicle control device that can improve vehicle safety compared to the above-mentioned conventional techniques. [Means for solving the problem]

[0011] One aspect of the present disclosure is a vehicle control device including a target speed calculation unit that calculates a target speed of a vehicle, the target speed calculation unit including a first speed calculation unit that calculates a first speed at which the vehicle can be stopped at a stopping position before the outer edge of a sensing range of an external sensor of the vehicle using a path length of a target route of the vehicle to the outer edge of the sensing range of the vehicle's external sensor and a friction coefficient of the road surface, a second speed calculation unit that calculates a second speed at which the vehicle can follow the target route using a radius of curvature of the target route and the friction coefficient, and a target speed setting unit that selects the smallest speed between the first speed and the second speed and sets it as the target speed. Effect of the Invention

[0012] According to the above aspect of the present disclosure, it is possible to provide a vehicle control device that can improve vehicle safety compared to the above-mentioned conventional technology. [Brief description of the drawings]

[0013] [Figure 1] 1 is a schematic diagram of a vehicle illustrating an embodiment of a vehicle control device according to the present disclosure. [Diagram 2] FIG. 2 is a block diagram of the vehicle shown in FIG. 1. [Diagram 3] FIG. 3 is a block diagram of the driving planner shown in FIG. 2 . [Figure 4] 4 is a flowchart showing an example of a process of a target speed calculation unit shown in FIG. 3. [Diagram 5] 5 is a plan view of the vehicle for explaining the process of identifying the sensing range shown in FIG. 4. [Figure 6] 5 is a plan view of the vehicle for explaining the process of identifying the sensing range shown in FIG. 4. [Figure 7] 5 is a plan view of the vehicle for explaining the process of identifying the sensing range shown in FIG. 4. [Figure 8] 5 is a plan view of the vehicle for explaining the process of identifying the sensing range shown in FIG. 4. [Figure 9] 5 is a plan view of the vehicle for explaining the process of identifying the sensing range shown in FIG. 4. [Figure 10] 5 is an explanatory diagram of a process of outputting a target speed from the process of acquiring a target route shown in FIG. 4. [Figure 11] 5 is a plan view illustrating a process of calculating each second speed shown in FIG. 4. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0014] Hereinafter, an embodiment of a vehicle control device according to the present disclosure will be described with reference to the drawings. Fig. 1 is a schematic diagram of a vehicle 10 illustrating an embodiment of a vehicle control device according to the present disclosure. Fig. 2 is a block diagram of the vehicle 10 shown in Fig. 1.

[0015] The vehicle 10 includes, for example, a power source 11, wheels 12, a steering wheel 13, a power steering 14, a shift lever 15, an accelerator pedal 16, a brake pedal 17, a brake caliper 18, and a hydraulic unit 19. The vehicle 10 also includes, for example, an external sensor 20, a vehicle sensor 30, a communication unit 40, a GNSS receiver 50, map data 60, and a vehicle control device 100. The configuration of each part of the vehicle 10 will be described in detail below.

[0016] The power source 11 is, for example, at least one of an engine and a motor, and drives the wheels 12 via a transmission. The wheels 12 have tires which are the ground contacting parts of the vehicle 10. The friction coefficient μ between the tires of the wheels 12 which are the ground contacting parts of the vehicle 10 and the road surface on which the vehicle 10 runs varies depending on, for example, the state of the road surface and weather conditions. The steering wheel 13 is operated by a driver who is an occupant of the vehicle 10 during manual driving. The power steering 14 generates a steering force according to the operation of the steering wheel 13.

[0017] The shift lever 15 is used by the driver to switch the state of the transmission between "D", "N", "P", "R", etc., when the vehicle 10 is being manually driven, for example. The accelerator pedal 16 is increased or decreased in amount by the driver when the vehicle 10 is being manually driven, for example, to increase or decrease the driving force output from the power source 11. The brake pedal 17 is increased or decreased in amount by the driver when the vehicle 10 is being manually driven, for example, to increase or decrease the braking force generated by the brake caliper 18 via the hydraulic unit 19.

[0018] The external sensor 20 is a sensor that acquires external information about the surroundings of the vehicle 10. The external sensor 20 includes, for example, a monocular camera 21, a stereo camera 22, a millimeter wave radar 23, a laser radar 24, and a sonar sensor 25. With these sensors, the external sensor 20 acquires, as external information, for example, the distance and direction from the vehicle 10 to an object, the relative speed of the object with respect to the vehicle 10, and the like.

[0019] If the external sensor 20 is equipped with at least the stereo camera 22, the target speed V tgt That is, the external sensor 20 does not need to include, for example, one or more of the monocular camera 21, the millimeter wave radar 23, the laser radar 24, and the sonar sensor 25.

[0020] The vehicle sensor 30 is a sensor that acquires driving information including the speed of the vehicle 10. The vehicle sensor 30 includes, for example, a steering angle sensor 31, a gyro sensor 32, an acceleration sensor 33, and a speed sensor 34. That is, the vehicle sensor 30 acquires driving information of the vehicle 10 including, for example, the steering angle, the angular velocities of roll, pitch, and yaw, the acceleration and deceleration in the front-rear direction of the vehicle 10, the lateral acceleration in the lateral direction of the vehicle 10, and the speed of the vehicle 10, by using these sensors. Note that, for example, a wheel speed sensor can be used as the speed sensor 34.

[0021] The communication unit 40 is connected to an external server such as a road administrator via, for example, a wireless communication line and an Internet line, and acquires various information such as road information, weather information, and road surface conditions, and inputs the information to the vehicle control device 100. The communication unit 40 can also transmit information output from the vehicle control device 100 to the outside via a wireless communication line. The communication unit 40 can also receive information detected by sensors installed on the road or in infrastructure outside the vehicle 10, and input the information to the vehicle control device 100.

[0022] The GNSS receiver 50 receives radio waves from a plurality of positioning satellites to acquire position information of the vehicle 10 and inputs the position information to the vehicle control device 100. The map data 60 is stored, for example, in a storage device mounted on the vehicle 10, and the GNSS receiver 50 inputs map information based on the position information of the vehicle 10 to the vehicle control device 100. Note that the map data 60 does not necessarily have to be stored in a storage device mounted on the vehicle 10, and may be received from the outside via the communication unit 40, for example.

[0023] The vehicle control device 100 is an electronic control device configured by, for example, a microcomputer equipped with a central processing unit (CPU), a memory, a program, a timer, an input / output unit, etc. The vehicle control device 100 includes, for example, an external environment recognition unit 110, a driving plan unit 120, a driving control unit 130, a brake control unit 140, a steering control unit 150, and a driving force control unit 160. Each of these units of the vehicle control device 100 may be configured by a microcomputer, or two or more of them may be integrated into one microcomputer. In addition, each unit of the vehicle control device 100 may represent a function of the vehicle control device 100 that is realized by, for example, executing a program by the CPU.

[0024] The external environment recognition unit 110 is, for example, a sensor fusion controller, and recognizes objects by acquiring external information from the external sensor 20. The external environment recognition unit 110 ensures the reliability required for autonomous driving of the vehicle 10 by integrating and selecting information acquired from multiple sensors of the external environment sensor 20, such as the monocular camera 21, the stereo camera 22, the millimeter wave radar 23, the laser radar 24, and the sonar sensor 25. In addition, the external environment recognition unit 110 outputs the object recognition result based on the external environment information acquired from the external sensor 20 to the driving plan unit 120 in an appropriate format.

[0025] 3 is a block diagram of the driving plan unit 120 shown in FIG. 2. The driving plan unit 120, for example, acquires driving information including the speed of the vehicle 10 from the vehicle sensor 30, acquires the object recognition result from the external environment recognition unit 110, and generates a driving plan for the vehicle 10. The driving plan unit 120 has, for example, a self-position estimation unit 121, a target route calculation unit 122, a lane keeping driving unit 123, an obstacle avoidance unit 124, a friction coefficient acquisition unit 125, and a target speed calculation unit 126. Note that if the driving plan unit 120 has at least the target speed calculation unit 126, it can calculate a target speed V tgt It is possible to calculate the following.

[0026] The self-position estimation unit 121 estimates the position of the vehicle 10 based on, for example, the position information of the vehicle 10 input from the GNSS receiver 50 and map information of the surroundings of the vehicle 10 acquired from the map data 60, and outputs the estimated position of the vehicle 10 to the target speed calculation unit 126. Furthermore, the self-position estimation unit 121 may estimate the position of the vehicle 10 based on the detection result of the vehicle sensor 30 in addition to the position information of the vehicle 10 input from the GNSS receiver 50 and the map information acquired from the map data 60.

[0027] The target route calculation unit 122 calculates a target route for the vehicle 10 based on, for example, the position of the vehicle 10 estimated by the self-position estimation unit 121, the destination of the vehicle 10 set by an occupant of the vehicle 10, and map information obtained from the map data 60.

[0028] For example, when the vehicle 10 is driven autonomously, the lane keeping driving unit 123 calculates a control amount for driving the vehicle 10 while maintaining the same lane without requiring steering operation by the driver of the vehicle 10.

[0029] The obstacle avoidance unit 124 calculates a driving route of the vehicle 10 for avoiding an obstacle present on the target route of the vehicle 10, for example, based on the recognition result of the external environment recognition unit 110. The estimation results and calculation results of the self-position estimation unit 121, the target route calculation unit 122, the lane keeping driving unit 123, and the obstacle avoidance unit 124 are output to the target speed calculation unit 126 and the driving control unit 130, for example.

[0030] The friction coefficient acquisition unit 125 acquires, for example, a friction coefficient μ between a tire, which is a ground contact portion of the vehicle 10, and a road surface on which the vehicle 10 runs. The method of acquiring the friction coefficient μ by the friction coefficient acquisition unit 125 is not particularly limited. The friction coefficient acquisition unit 125 can acquire the friction coefficient μ by a known method, such as estimating the friction coefficient μ based on the vibration behavior of the tire tread, estimating the friction coefficient μ based on the lateral acceleration and yaw angular velocity of the vehicle 10, or estimating the friction coefficient μ from the slip angle of the wheel 12 and the lateral acceleration of the vehicle 10. The friction coefficient acquisition unit 125 outputs the acquired friction coefficient μ to the target speed calculation unit 126.

[0031] The target speed calculation unit 126 includes, for example, a first speed calculation unit 126a, a second speed calculation unit 126b, and a target speed setting unit 126f. The target speed calculation unit 126 can also include, for example, at least one of a legal speed acquisition unit 126c, a set speed acquisition unit 126d, and an upper limit speed setting unit 126e. Each unit of the target speed calculation unit 126 shown in FIG. 3 indicates each function of the target speed calculation unit 126 that is realized by, for example, executing a program by a CPU.

[0032] Fig. 4 is a flow diagram showing an example of the process of the target speed calculation unit 126 shown in Fig. 3. Figs. 5 to 9 are plan views of the vehicle 10 for explaining the process P1 for specifying the sensing range shown in Fig. 4. Fig. 10 is a flow diagram showing an example of the process P2 for acquiring the target route shown in Fig. 4 to obtain the target speed Vtgt 11 is a plan view for explaining a process P8 for outputting the second velocity V 2i 13 is a plan view for explaining a process P5 for calculating

[0033] 4, the target speed calculation unit 126 first executes a process P1 for identifying the sensing range of the external sensor 20. In this process P1, the first speed calculation unit 126a identifies the sensing range SR of the external sensor 20, for example, as described below. Note that the function for identifying the sensing range SR of the external sensor 20 can be provided, for example, as a sensing range identification unit independent of the first speed calculation unit 126a. In this case, the sensing range identification unit can be provided, for example, inside the target speed calculation unit 126, inside the driving plan unit 120, or inside the external environment recognition unit 110.

[0034] The first speed calculation unit 126a specifies, as the sensing range SR, a range in which an object can be detected based on the specifications of, for example, the monocular camera 21, the stereo camera 22, the millimeter wave radar 23, the laser radar 24, the sonar sensor 25, etc. Such a range in which an object can be detected based on the specifications of the external sensor 20 is, for example, stored in advance in the memory of the travel plan unit 120.

[0035] Specifically, the first speed calculation unit 126a identifies the sensing range SR based on the detectable distance D of each sensor constituting the external sensor 20 mounted on the vehicle 10, the detectable angle α such as the angle of view of each sensor, and the overlapping detectable ranges, for example, as shown in Figures 5 and 6.

[0036] 7, the first speed calculation unit 126a may specify a reduced or enlarged sensing range SR of the monocular camera 21 or the stereo camera 22 depending on weather conditions. In this case, the first speed calculation unit 126a can acquire the amount of rainfall, the amount of snowfall, or the density of fog based on, for example, the state of the wiper switch (weak, medium, strong), the images of the monocular camera 21 or the stereo camera 22, or weather information received via the communication unit 40.

[0037] More specifically, the first speed calculation unit 126a sets a threshold value for weather conditions such as the amount of rainfall, the amount of snowfall, and the density of fog, and when the threshold value is exceeded, identifies a sensing range SR that is smaller than the previous sensing range SR. In the example shown in Fig. 7, the first speed calculation unit 126a identifies a sensing range SR0 of the most expanded detectable distance D0 until the amount of rainfall, the amount of snowfall, or the density of fog exceeds the first threshold value.

[0038] 7, the first speed calculation unit 126a specifies a sensing range SR1 of a detectable distance D1 that is smaller than the previous sensing range SR0 until the amount of rainfall, the amount of snowfall, or the density of fog exceeds the first threshold and then the second threshold. Furthermore, when the amount of rainfall, the amount of snowfall, or the density of fog exceeds the first threshold and then the second threshold, the first speed calculation unit 126a specifies a sensing range SR2 of a detectable distance D2 that is smaller than the previous sensing range SR1.

[0039] Also, as shown in the example of Fig. 8, when the brightness falls below a predetermined threshold value, such as at night or inside a tunnel where no lighting is installed, the first speed calculation unit 126a specifies a sensing range SR3 that corresponds to the headlight illumination range that is smaller than the previous sensing range SR0. Also, as shown in the example of Fig. 9, when a blind spot BA occurs in the sensing range SR of the external sensor 20 due to, for example, an oncoming vehicle, a guard rail, or a building, the target speed calculation unit 126 specifies a sensing range SR that excludes the blind spot BA.

[0040] Next, the first speed calculation unit 126a executes a process P2 of acquiring a target route TR, for example, as shown in Fig. 4 and Fig. 10. As described above, this target route TR is, for example, calculated by the target route calculation unit 122, input to the target speed calculation unit 126, and acquired by the first speed calculation unit 126a.

[0041] Next, the first speed calculation unit 126a executes a process P3 for calculating a path length l1 of the target route TR to the outer edge SRp of the sensing range SR, for example, as shown in Fig. 4 and Fig. 10. In this process P3, the first speed calculation unit 126a calculates the path length l1 of the target route TR of the vehicle 10 to the outer edge SRp of the sensing range SR, based on, for example, the sensing range SR identified in the above-mentioned process P1 and the target route TR acquired in the above-mentioned process P2.

[0042] Next, the first speed calculation unit 126a executes a process P4 for calculating a first speed V1, for example, as shown in Fig. 4. In this process P4, the first speed calculation unit 126a calculates an upper limit deceleration g1 of the vehicle 10, for example, by using the path length l1 of the target route TR to the outer edge SRp of the sensing range SR calculated in the above-mentioned process P3 and the friction coefficient μ of the road surface acquired from the friction coefficient acquisition unit 125. This upper limit deceleration g1 is an upper limit deceleration at the time of an emergency stop of the vehicle 10, calculated, for example, based on the friction coefficient μ of the road surface on which the vehicle 10 runs and further multiplied by a safety factor.

[0043] Then, the first speed calculation unit 126a calculates a first speed V1 at which the vehicle 10 can be stopped at a stopping position before the outer edge SRp of the sensing range SR, for example, by the following formula (1). This first speed V1 is a speed at which the vehicle 10 traveling along the target route TR can be stopped at a stopping position before the outer edge SRp of the sensing range SR of the external sensor 20, with a deceleration that does not exceed an upper limit deceleration g1.

[0044]

number

[0045] Next, the second speed calculation unit 126b executes processes P5 and P6 for calculating a second speed V2 at which the vehicle 10 can follow the target route TR, as shown in FIG. 4 and FIG.

[0046] More specifically, the second speed calculation unit 126b, for example, first acquires the upper limit deceleration g2 before the vehicle 10 enters a curve. The upper limit deceleration g2 before the vehicle 10 enters a curve is set to a predetermined deceleration that does not cause discomfort to the occupants of the vehicle 10, for example, and is stored in advance in the storage device of the vehicle control device 100.

[0047] Further, the second speed calculation unit 126b calculates an upper limit lateral acceleration g3 when passing through each of the curves C1, C2, and C3 of the target route TR included in the sensing range SR of the external sensor 20. The upper limit lateral acceleration g3 can be set to a lateral acceleration at which the vehicle 10 does not slip due to the centrifugal force acting on the vehicle 10 traveling around each of the curves C1, C2, and C3, for example.

[0048] Such lateral acceleration can be calculated based on, for example, the coefficient of friction μ between the road surface and the tires of the vehicle 10, the contact area, the acceleration of gravity, and the radii of curvature r1, r2, r3 of the curves C1, C2, C3. The radii of curvature r1, r2, r3 of the curves C1, C2, C3 may be obtained from the map data 60, or may be obtained by acquiring the road shape ahead of the vehicle 10 using the monocular camera 21, the stereo camera 22, the laser radar 24, or the like.

[0049] Next, the second speed calculation unit 126b calculates the second speed V of the vehicle 10 when traveling along each of the curves C1, C2, C3, . . . , Ci of the target route TR included in the sensing range SR, for example, by using the following equation (2): 21 ,V 22 ,V 23 ,···,V 2i In the following formula (2), l 21 ,l 22 ,l 23 ,···,l2i As shown in FIG. 11, C1, C2, C3, . . . , Ci are the path lengths from the vehicle 10 to the entry positions of the respective curves C1, C2, C3, . . . , Ci.

[0050]

number

[0051] The second velocity V in each of the above equations (2) 21 ,V 22 ,V 23 ,···,V 2i is a speed at which the vehicle 10 can decelerate at the upper limit deceleration g2 to the entry positions C1i, C2i, C3i, . . . , Cii of the curves C1, C2, C3, . . . , Ci and can turn around each of the curves C1, C2, C3, . . . , Ci, as shown in Fig. 11. In other words, the second speed calculation unit 126b calculates, for example, the second speed V at which the vehicle 10 can decelerate at a deceleration that does not exceed the predetermined upper limit deceleration g2 to the entry positions C1i, C2i, C3i, . . . , Cii. 21 ,V 22 ,V 23 ,···,V 2i Calculate.

[0052] In the example shown in FIG. 11, the second velocity calculation unit 126b calculates the second velocity V 21 ,V 22 ,V 23 ,···,V 2i Let radii of curvature r1, r2, r3, . . . , r i For example, the second speed calculation unit 126b calculates the second speed V at which the vehicle 10 can decelerate at a deceleration that does not exceed a predetermined upper limit deceleration g2 by the time the vehicle 10 enters each section, with each section being a unit obtained by dividing the target route TR by a predetermined division length. 21 ,V 22 ,V 23 ,···,V 2i may be calculated.

[0053] For example, the second speed calculation unit 126b does not use the upper limit deceleration g2, but uses only the upper limit lateral acceleration g3 to calculate each of the second speeds V 21 ,V 22 ,V 23 ,···,V 2i In this case, the term including the upper limit deceleration g2 in the above formula (2) becomes zero. Then, each second speed V 21 ,V 22 ,V 23 ,···,V 2i are the speeds at which the vehicle can turn around each curve C1, C2, C3, . . . , Ci, that is, the radii of curvature r1, r2, r3, . . . , r i and the friction coefficient μ of the road surface, the speed at which the vehicle 10 can follow the target route TR is calculated.

[0054] Furthermore, for example, when the upper limit lateral acceleration g3 calculated as described above exceeds a range of lateral acceleration that does not cause discomfort to the occupants of the vehicle 10, the second speed calculation unit 126b may set the upper limit lateral acceleration of that range as the upper limit lateral acceleration g3. That is, the second speed calculation unit 126b may calculate the second speed V2 capable of following the target route TR at a lateral acceleration that does not exceed a predetermined upper limit lateral acceleration g3, such as a lateral acceleration that does not cause discomfort to the occupants of the vehicle 10.

[0055] Next, the second speed calculation unit 126b executes a process P6 for selecting the minimum second speed V2, as shown in FIG. 4. In this process P6, the second speed calculation unit 126b calculates the minimum second speed V2 by using, for example, the following formula (3): 21 ,V 22 ,V 23 ,···,V 2i Among these, the smallest speed is set as the second speed V2. This makes it possible to set the second speed V2 to a speed at which the vehicle 10 can follow the entire target route TR included in the sensing range SR.

[0056]

number

[0057] Next, the target speed setting unit 126f sets the target speed V tgt In this process P7, the target speed setting unit 126f selects the smallest speed from the first speed V1 and the second speed V2 using, for example, the following formula (4), to set the target speed V tgt This sets the target speed V tgt can be set to a speed at which the vehicle 10 can be stopped at a stopping position just before the outer edge SRp of the sensing range SR of the external sensor 20 and at which the vehicle 10 can follow the target route TR.

[0058]

number

[0059] Next, the travel plan unit 120 calculates and sets the target speed V tgt For example, the travel planning unit 120 executes a process P8 in which the travel planning unit 120 outputs the target speed V tgt The driving control unit 130 outputs the target speed V tgt and the target route TR, the control unit 130 outputs control commands to the brake control unit 140, the steering control unit 150, and the driving force control unit 160.

[0060] The brake control unit 140, the steering control unit 150, and the driving force control unit 160 respectively control the hydraulic unit 19, the brake caliper 18, the power steering 14, and the power source 11 based on control commands input from the driving control unit 130. This enables the vehicle 10 to be driven autonomously.

[0061] The operation of the vehicle control device 100 of this embodiment will be described below.

[0062] The vehicle control device 100 of this embodiment is configured to detect a target speed V tgtThe target speed calculation unit 126 includes a first speed calculation unit 126a, a second speed calculation unit 126b, and a target speed setting unit 126f. The first speed calculation unit 126a calculates a first speed V1 at which the vehicle 10 can stop at a stopping position just before the outer edge SRp of the sensing range SR of the external sensor 20 of the vehicle 10, using the path length l1 of the target route TR of the vehicle 10 to the outer edge SRp of the sensing range SR of the external sensor 20 of the vehicle 10 and the friction coefficient μ of the road surface. The second speed calculation unit 126b calculates a first speed V1 at which the vehicle 10 can stop at a stopping position just before the outer edge SRp, using the radii of curvature r1, r2, r3,...,r i and the friction coefficient μ, a second speed V2 at which the vehicle 10 can follow the target route TR is calculated. The target speed setting unit 126f then selects the smallest speed between the first speed V1 and the second speed V2 to set the target speed V tgt Set to.

[0063] With this configuration, even if the target route TR included in the sensing range SR includes the curves C1, C2, C3, . . . , Ci, the vehicle control device 100 can prevent the vehicle 10 from slipping and make the vehicle 10 travel along the target route TR. Furthermore, even if an obstacle exists outside the sensing range SR of the external sensor 20, the vehicle 10 can be reliably stopped before the obstacle. Therefore, according to this embodiment, it is possible to provide a vehicle control device 100 that can suppress a decrease in safety due to an obstacle that cannot be detected by the external sensor 20 while the vehicle 10 is traveling along the target route TR including the curves C1, C2, C3, . . . , Ci, and improve the safety of the vehicle 10.

[0064] In the vehicle control device 100 of this embodiment, the first speed calculation unit 126a calculates a first speed V1 at which the vehicle 10 can stop at the above-mentioned stop position with a deceleration that does not exceed a predetermined upper limit deceleration g1. The second speed calculation unit 126b calculates a second speed V2 at which the vehicle 10 can follow the target route TR with a lateral acceleration that does not exceed a predetermined upper limit lateral acceleration g3.

[0065] With this configuration, the vehicle control device 100 of the present embodiment can more reliably stop the vehicle 10 at a stop position before the outer edge SRp of the sensing range SR by using the upper limit deceleration at the time of an emergency stop of the vehicle 10 described above as the predetermined upper limit deceleration g1. In addition, by using an upper limit deceleration that does not cause discomfort to the occupants of the vehicle 10 as the predetermined upper limit deceleration g1, the vehicle 10 can be stopped at a stop position before the outer edge SRp of the sensing range SR without causing discomfort to the occupants of the vehicle 10. Furthermore, by using an upper limit lateral acceleration that does not cause discomfort to the occupants of the vehicle 10 as the predetermined upper limit lateral acceleration g3, the vehicle 10 can pass through the target route TR including the curves C1, C2, C3, . . . , Ci without causing discomfort to the occupants of the vehicle 10.

[0066] Furthermore, in the vehicle control device 100 of this embodiment, the second speed calculation unit 126b calculates a second speed V2 at which the vehicle 10 can decelerate at a deceleration that does not exceed a predetermined upper limit deceleration g2 until reaching the entry positions C1i, C2i, C3i, ···, Cii of each of the curves C1, C2, C3, ···, Ci having different radii of curvature r1, r2, r3, ···, ri included in the target route TR.

[0067] With this configuration, the vehicle control device 100 of this embodiment can use, as the predetermined upper limit deceleration g2, an upper limit deceleration that does not cause discomfort to the occupants of the vehicle 10. This allows the vehicle 10 to decelerate to a speed that allows the vehicle 10 to complete the curve C1, C2, C3, ..., Ci by the approach position C1i, C2i, C3i, ..., Cii of the curve C1, C2, C3, ..., Ci without causing discomfort to the occupants of the vehicle 10.

[0068] Furthermore, in the vehicle control device 100 of this embodiment, the second speed calculation unit 126b can also calculate the second speed V2 at which the vehicle 10 can decelerate at a deceleration that does not exceed a predetermined upper limit deceleration g2 up to the entry position of each section obtained by dividing the target route TR by a predetermined division length, as described above.

[0069] With this configuration, as described above, the vehicle control device 100 of this embodiment can use, as the predetermined upper limit deceleration g2, an upper limit deceleration that does not cause discomfort to the occupants of the vehicle 10. This allows the vehicle 10 to decelerate to a speed at which the vehicle 10 can follow each section of the target route TR by the time the vehicle 10 reaches the entry position of each section of the target route TR, without causing discomfort to the occupants of the vehicle 10.

[0070] In the vehicle control device 100 of this embodiment, the target speed calculation unit 126 includes a legal speed acquisition unit 126c that acquires the legal speed of the target route TR. In this case, the target speed setting unit 126f selects the smallest speed among the first speed V1, the second speed V2, and the legal speed, and sets the target speed V tgt Set to.

[0071] With this configuration, it is possible to prevent the speed of the vehicle 10 from exceeding the legal speed. The legal speed acquisition unit 126c may acquire the legal speed of the target route TR, for example, from the map data 60, or may acquire it based on the recognition result of the road sign by the external environment recognition unit 110.

[0072] In the vehicle control device 100 of this embodiment, the target speed calculation unit 126 includes a set speed acquisition unit 126d that acquires a set speed set by an occupant of the vehicle 10. In this case, the target speed setting unit 126f selects the smallest speed among the first speed V1, the second speed V2, and the set speed, and sets the target speed V tgt Set to.

[0073] With this configuration, it is possible to prevent the speed of the vehicle 10 from exceeding the set speed. The set speed acquisition unit 126d may acquire the speed set by the occupant of the vehicle 10, for example, from an input device such as a touch panel mounted on the vehicle 10, or may acquire the speed by a microphone mounted on the vehicle 10 and a voice recognition unit that recognizes the voice of the occupant.

[0074] In the vehicle control device 100 of this embodiment, the target speed calculation unit 126 includes an upper speed limit setting unit 126e that sets an upper speed limit according to the width of the road of the target route TR. In this case, the target speed setting unit 126f selects the smallest speed among the first speed V1, the second speed V2, and the upper speed limit to set the target speed V tgt Set to.

[0075] With this configuration, it is possible to prevent the speed of the vehicle 10 from exceeding the upper speed limit set according to the width of the road, thereby improving the safety of the vehicle 10. Note that the upper speed limit setting unit 126e may obtain the width of the road of the target route TR, for example, from the map data 60, or may obtain the width based on the recognition result of the road sign by the external environment recognition unit 110.

[0076] The vehicle control device 100 of this embodiment also includes an external environment recognition unit 110, a driving plan unit 120, and a driving control unit 130. The external environment recognition unit 110 acquires external environment information from the external environment sensor 20 and recognizes objects. The driving plan unit 120 acquires driving information including the speed of the vehicle 10 from the vehicle sensor 30 of the vehicle 10, acquires the recognition result of the object from the external environment recognition unit 110, and generates a driving plan for the vehicle 10. The driving control unit 130 drives the vehicle 10 at a target speed V along a target route TR. tgt The driving plan unit 120 includes a target speed calculation unit 126, a target route calculation unit 122 that calculates a target route TR, and a friction coefficient acquisition unit 125 that acquires a friction coefficient μ between the ground contact portion of the vehicle 10 and the road surface.

[0077] With this configuration, the vehicle control device 100 of the present embodiment can control the vehicle 10 to follow the target route TR and to reliably stop the vehicle before an obstacle by setting a target speed V tgt It is possible to calculate the vehicle speed and the vehicle 10 can be automatically driven. Therefore, according to the present embodiment, it is possible to provide a vehicle control device 100 that can improve the safety of the vehicle 10 more than the conventional technology.

[0078] The above describes in detail an embodiment of the vehicle control device according to the present disclosure using the drawings, but the specific configuration is not limited to this embodiment, and even if there are design changes, etc., within the scope that does not deviate from the gist of the present disclosure, they are included in the present disclosure. [Explanation of symbols]

[0079] 10 vehicle, 20 external sensor, 100 vehicle control device, 110 external recognition unit, 120 travel planning unit, 122 target route calculation unit, 125 friction coefficient acquisition unit, 126 target speed calculation unit, 126a first speed calculation unit, 126b second speed calculation unit, 126c legal speed acquisition unit, 126d set speed acquisition unit, 126e upper limit speed setting unit, 126f target speed setting unit, 130 travel control unit, C1-Ci curve, C1i-Cii entry position, g1 upper limit deceleration, g2 upper limit deceleration, g3 upper limit lateral acceleration, l1 route length, V tgt Target speed, r1-r i radius of curvature, SR sensing range, SRp outer edge, TR target path, V1 first velocity, V2 second velocity, μ friction coefficient.

Claims

1. A vehicle control device including a target speed calculation unit that calculates a target speed of a vehicle, The target speed calculation unit a first speed calculation unit that calculates a first speed at which the vehicle can be stopped at a stop position before the outer edge of a sensing range of an external sensor of the vehicle, using a path length of a target path of the vehicle to the outer edge of the sensing range of an external sensor of the vehicle and a friction coefficient of a road surface; a second speed calculation unit that calculates a second speed at which the vehicle can follow the target route by using a radius of curvature of the target route and the friction coefficient; a target speed setting unit that selects a minimum speed from the first speed and the second speed and sets the selected speed as the target speed.

2. The first speed calculation unit calculates the first speed at which the vehicle can stop at the stop position at a deceleration that does not exceed a predetermined upper limit deceleration, The vehicle control device according to claim 1 , wherein the second speed calculation unit calculates the second speed at which the target route can be tracked at a lateral acceleration that does not exceed a predetermined upper limit lateral acceleration.

3. The vehicle control device according to claim 1, characterized in that the second speed calculation unit calculates the second speed at which the vehicle can decelerate at a deceleration that does not exceed a predetermined upper limit deceleration by the time the vehicle enters each curve with a different radius of curvature included in the target route.

4. 2. The vehicle control device according to claim 1, wherein the second speed calculation unit calculates the second speed at which the vehicle can decelerate at a deceleration that does not exceed a predetermined upper limit deceleration by the entry position of each section obtained by dividing the target route by a predetermined division length.

5. The target speed calculation unit includes a legal speed acquisition unit that acquires a legal speed of the target route, 5. The vehicle control device according to claim 1, wherein the target speed setting unit selects a minimum speed from the first speed, the second speed, and the legal speed, and sets the selected speed as the target speed.

6. the target speed calculation unit includes a set speed acquisition unit that acquires a set speed set by an occupant of the vehicle; 5. The vehicle control device according to claim 1, wherein the target speed setting unit selects a minimum speed from the first speed, the second speed, and the set speed, and sets the selected speed as the target speed.

7. the target speed calculation unit includes an upper limit speed setting unit that sets an upper limit speed in accordance with a width of a road of the target route, 5. The vehicle control device according to claim 1, wherein the target speed setting unit selects a minimum speed from the first speed, the second speed, and the upper limit speed, and sets the selected speed as the target speed.

8. an external environment recognition unit that acquires external environment information from the external environment sensor and recognizes an object; A driving planner that acquires driving information including a speed of the vehicle from a vehicle sensor of the vehicle, acquires a recognition result of the object from the external environment recognition unit, and generates a driving plan for the vehicle; a travel control unit that causes the vehicle to travel at the target speed along the target route, 2. The vehicle control device according to claim 1, wherein the driving planner comprises: the target speed calculator; a target route calculator that calculates the target route; and a friction coefficient acquirer that acquires the friction coefficient between the ground contact portion of the vehicle and the road surface.

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