Vehicle motion control device and vehicle motion control method

Abstract

To provide a vehicle motion control device which achieves riding comfort and minimization of transit time by setting a speed such that physical quantities such as acceleration and jerk fall within specified values after considering cooperation between the longitudinal motion and the lateral motion generated in a vehicle during travel.SOLUTION: A vehicle motion control device comprises: route command value calculation means which generates a route on which a vehicle travels; specified value setting means which sets a specified value of a physical quantity of a vehicle behavior when traveling on the route; route feature point setting means which sets a route feature point on the basis of the route and the specified value; and speed command value calculation means which calculates a speed for the vehicle to travel on the route on the basis of the route, the specified value and the route feature point. The speed command value calculation means sets a zero point of the longitudinal acceleration on the basis of the route feature point being the peak point of the curvature of the route, and sets the peak point of the longitudinal acceleration on the basis of the route feature point being the peak point of a distance differential value of the curvature.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a vehicle motion control device and a vehicle motion control method for controlling the motion of a vehicle in accordance with a travel route. [Background technology]

[0002] One type of vehicle motion control technology, typified by driver assistance and autonomous driving, is a technology that generates a driving trajectory consisting of information such as the vehicle's target driving route and driving speed, and controls the powertrain, brakes, steering, etc. so that the vehicle travels along that trajectory. The simplest example of driving route control is lane keeping control, which sets the driving route to the center of the lane.

[0003] Furthermore, a more advanced driving path control technology is disclosed, for example, in Patent Document 1, and the latter part of claim 1 of Patent Document 1 describes a driving assistance method that "calculates, based on the driving road condition information, constraint conditions that constrain the first friction circle characteristics of longitudinal acceleration and lateral acceleration due to the tire grip limits to be equal to or less than the longitudinal acceleration values ​​and lateral acceleration values ​​due to the tire grip limits, uses the constraint conditions to generate a target speed profile along the target trajectory, and performs driving assistance in accordance with the target speed profile when the host vehicle drives along the target trajectory."

[0004] As described above, Patent Document 1 is directed to a driving assistance method that assumes tire grip limits due to factors such as the curvature of the road on which the vehicle will travel in the future, and discloses a driving assistance method that, in a scene in which the vehicle travels along a target trajectory, generates a target speed profile for the vehicle based on constraints imposed by the tire grip limits, thereby preventing the vehicle's driving trajectory from deviating from the target trajectory regardless of the road conditions ahead of the vehicle. [Prior art documents] [Patent documents]

[0005] [Patent Document 1] Patent Publication No. 2021-049867 Summary of the Invention [Problem to be solved by the invention]

[0006] However, the driving assistance method of Patent Document 1 is merely a technology for suppressing peak values ​​of longitudinal acceleration and lateral acceleration based on tire grip limits, and is not a technology for improving the ride quality and comfort of occupants. Therefore, suppressing peak values ​​of longitudinal acceleration and lateral acceleration using the technology of Patent Document 1 can result in an increase in the number of accelerations and decelerations to compensate for a decrease in vehicle speed, or in unstable vehicle behavior, which can impair the ride quality and comfort of occupants.

[0007] Therefore, the present invention aims to provide a vehicle motion control device that improves the ride quality and comfort of occupants by taking into consideration the coordination between longitudinal and lateral motion, such as aligning the peak point of the curvature of the driving path with the zero point of the longitudinal acceleration of the vehicle, and setting the speed of the vehicle so that physical quantities related to vehicle behavior, such as acceleration and jerk, are within specified values. [Means for solving the problem]

[0008] In order to solve the above-mentioned problems, the vehicle motion control device of the present invention includes a route planning unit that generates a route for the vehicle to travel, a specified value setting unit that sets specified values ​​for physical quantities of the vehicle behavior when traveling along the route, a route feature point setting unit that sets route feature points based on the route and the specified values, and a traveling speed generation unit that generates a speed command value for the vehicle to travel along the route based on the route, the specified values, and the route feature points, wherein the traveling speed generation unit sets a zero point of longitudinal acceleration based on the route feature points that are peak points of the curvature of the route, and sets a peak point of longitudinal acceleration based on the route feature points that are peak points of the distance derivative of the curvature. [Effects of the Invention]

[0009] According to the vehicle motion control device or vehicle motion control method of the present invention, the vehicle speed is set so that physical quantities related to vehicle behavior, such as acceleration and jerk, fall within specified values, taking into consideration the link between longitudinal motion and lateral motion, such as aligning the peak point of the curvature of the travel route with the zero point of the longitudinal acceleration of the vehicle, thereby improving the ride quality and comfort of occupants. Note that problems, configurations, and effects other than those described above will become clear from the description of the embodiments below. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a functional block diagram of an in-vehicle system according to a first embodiment. [Figure 2] FIG. 2 is a functional block diagram of a travel trajectory generation unit according to the first embodiment. [Figure 3] FIG. 3 is a functional block diagram of a speed planning unit according to the first embodiment. [Figure 4] Plan view of the travel route. [Figure 5A] Curvature of the path command value where the curvature change is linear, distance differential value of the curvature, and path characteristic points. [Figure 5B] Curvature of the path command value with nonlinear curvature change, distance differential value of curvature, and path characteristic points. [Figure 6] 10 is a flowchart showing an outline of processing by a speed planning unit according to the first embodiment. [Figure 7A] 10 is an example of a physical quantity graph when the speed command value in step S31 is used during traveling. [Figure 7B] 10 is an example of a physical quantity graph when the speed command value in step S33 is used during traveling. [Figure 7C] 10 is an example of a physical quantity graph when the speed command value in step S35 is used during traveling. [Figure 8A] An example of a physical quantity graph when the specified vehicle speed value is changed while driving. [Figure 8B] Another example of a physical quantity graph when the specified vehicle speed value is changed while driving. [Figure 9] 10 is a flowchart showing an outline of processing by a speed planning unit according to the second embodiment. [Figure 10A]10 is an example of a physical quantity graph when the speed command value in step S5 is used during traveling. [Figure 10B] 10 is an example of a physical quantity graph when the speed command value in step S6 is used during traveling. [Figure 11] 11 is a flowchart showing an outline of processing by a speed planning unit according to the third embodiment. [Figure 12] 10 is an example of a physical quantity graph when the speed command value in step S8 is used during traveling. [Figure 13] 10 is a flowchart showing an outline of processing by a speed planning unit according to the fourth embodiment. [Figure 14] FIG. 13 is a functional block diagram of a speed planning unit according to a fifth embodiment. DETAILED DESCRIPTION OF THE INVENTION

[0011] Hereinafter, an embodiment of the vehicle motion control device of the present invention will be described with reference to the drawings. Note that substantially the same or similar components are denoted by the same reference numerals, and where explanations are redundant, those explanations may be omitted. Also, explanations of well-known technologies may be omitted. [Example]

[0012] First, a vehicle motion control device 2 according to a first embodiment of the present invention will be described with reference to FIGS.

[0013] <In-vehicle system 1> 1 is a functional block diagram of an in-vehicle system 1 having a vehicle motion control device 2 of this embodiment. The in-vehicle system 1 is a system that is installed in a vehicle and performs vehicle motion control such as driving assistance and autonomous driving, and as shown in the figure, has an external communication device 11, a GNSS (Global Navigation Satellite System) 12, a map information storage unit 13, sensors 14, an HMI (human machine interface) unit 15, the vehicle motion control device 2, a powertrain system 6, a brake system 7, and a steering system 8. These will be described in order below.

[0014] <Information sources for vehicle motion control device 2> The external vehicle communication device 11 performs vehicle-to-vehicle communication between the vehicle itself and another vehicle, or road-to-vehicle communication between the vehicle itself and a roadside device, by wireless communication, and transmits and receives information about the vehicle and the surrounding environment.

[0015] The GNSS 12 receives radio waves transmitted from artificial satellites such as quasi-zenith satellites and GPS (Global Positioning System) satellites, and acquires information such as the position of the vehicle.

[0016] The map information storage unit 13 stores general road information used in navigation systems, road information including information on curves such as road width and road curvature, information on road surface conditions and traffic conditions, information on the driving conditions of other vehicles, information on the vehicle and surrounding environment, etc. The information on the vehicle and surrounding environment, etc. is updated successively by information acquired through vehicle-to-vehicle communication and road-to-vehicle communication via the exterior communication device 11.

[0017] The sensor 14 is an external environment recognition sensor such as an image sensor, millimeter-wave radar, or lidar that detects information about the vehicle and the surrounding environment, or a sensor that detects information about driver operations, vehicle speed, acceleration, jerk, angular velocity, and wheel steering angle. The information about the vehicle and the surrounding environment detected by the external environment recognition sensor is, for example, information about various objects present around the vehicle, such as obstacles, signs, lane boundaries, lane outer lines, buildings, pedestrians, and other vehicles. The sensor 14 also recognizes lane boundaries, lane outer lines, and the like, based on, for example, the difference in brightness between the white lines in image data captured by the image sensor and the road surface.

[0018] The HMI unit 15 displays on the display and provides audio guidance from the speaker the information required by the user from information received through user input operations such as selection of a driving mode and setting of a destination, information acquired by the external communication device 11, the GNSS 12, and the sensors 14, and information recorded in the map information storage unit 13. The HMI unit 15 also issues an alarm to alert the user.

[0019] Here, the driving mode includes, for example, comfort mode, economy mode, sport mode, etc. The driving mode is set arbitrarily by the user, or set in advance by the user, or set by the operation management unit 3 (described later) based on driving situation information, and the vehicle speed, acceleration, jerk, etc. are set. Therefore, the specified value setting unit 31 of the operation management unit 3 changes specified values ​​for the vehicle behavior according to the set driving mode. Note that the driving mode includes a minimum time mode that minimizes travel time, a minimum distance mode that minimizes travel distance, etc.

[0020] <Vehicle motion control device 2> 1, the vehicle motion control device 2 has an operation management unit 3, a traveling trajectory generation unit 4, and a traveling control unit 5. Specifically, the vehicle motion control device 2 is an ECU (Electronic Control Unit) that has an arithmetic unit such as a CPU (Central Processing Unit), a main memory device such as a semiconductor memory, an auxiliary memory device, and hardware such as a communication device, and performs overall control of the vehicle, and realizes various functions of the operation management unit 3 and the like by executing a program loaded into the main memory device on the arithmetic unit. Note that in this embodiment, for convenience of explanation, the operation management unit 3, the traveling trajectory generation unit 4, and the traveling control unit 5 have separate configurations, but they do not necessarily have to have separate configurations, and when these units are used in an actual vehicle, the various functions of these units may be realized by a higher-level controller.

[0021] The traffic management unit 3 generates information on the vehicle's position, information on various objects around the vehicle (such as information on the vehicle and the surrounding environment), and information on vehicle behavior, such as lateral acceleration, yaw rate, and lateral jerk, based on information acquired by the external communication device 11, the GNSS 12, and the sensors 14, and map information stored in the map information storage unit 13. The traffic management unit 3 periodically transmits the vehicle's position information, information on various objects, and information on vehicle behavior to other vehicles and roadside devices via the external communication device 11, and also transmits the information to the map information storage unit 13, thereby successively updating the map information stored in the map information storage unit 13. Furthermore, the traffic management unit 3 sets information on a route from the vehicle's current position to a destination based on the vehicle's position information, information on various objects, and information on vehicle behavior, as well as information received by the HMI unit 15 (such as a driving mode and a destination). The route information set here includes a specified value for vehicle behavior, which is set by a specified value setting unit 31 of the traffic management unit 3 according to the driving mode. Hereinafter, the information generated or set by the operation management unit 3 may be referred to as "traveling situation information."

[0022] As shown in FIG. 2, the traveling trajectory generation unit 4 includes an information acquisition unit 41, a route planning unit 42, a speed planning unit 43, and an information output unit 44. In the traveling trajectory generation unit 4, the route planning unit 42 generates a route (hereinafter referred to as a "route command value P") that serves as a traveling target when the vehicle travels on a road, based on traveling situation information transmitted from the traffic management unit 3 and acquired by the information acquisition unit 41. Here, the route command value P is a command value generated based on, for example, information about the vicinity of the vehicle acquired by the sensor 14 or the like, or information combining distant map information recorded in the map information storage unit 13 or the like with the aforementioned nearby information, but the method for generating the route command value P is not limited. Then, the speed planning unit 43 generates a speed (hereinafter referred to as a "speed command value") that serves as a traveling target when the vehicle travels on a road, based on the route command value P and the traveling trajectory information, and the information output unit 44 outputs a traveling trajectory composed of information such as the route command value P and the speed command value to the traveling control unit 5. The speed planning unit 43 will be described in detail later.

[0023] The driving control unit 5 sets a target driving force, a target braking force, a target steering angle, etc., and controls the powertrain system 6, the brake system 7, and the steering system 8 so that the vehicle follows the driving trajectory output from the driving trajectory generation unit 4.

[0024] <Controlled Objects of Vehicle Motion Control Device 2> The powertrain system 6 controls the driving force generated by the internal combustion engine, the electric motor, etc., based on the operation by the driver and the target driving force output from the driving control unit 5.

[0025] The brake system 7 controls the braking force generated by the brake calipers and the like based on the operation by the driver or the target braking force output from the cruise control unit 5.

[0026] The steering system 8 controls the steering angle of the wheels based on the operation by the driver and the target steering angle output from the cruise control unit 5.

[0027] <Speed ​​Planning Section 43> Next, the speed planning unit 43 will be described in detail using the functional block diagram of Fig. 3. The speed planning unit 43 generates a speed command value for the vehicle based on the vehicle's position, speed, upper limit value of behavior, route command value P, etc., and has an information acquisition unit 43a, a route characteristic point setting unit 43b, a traveling speed generation unit 43c, and an information output unit 43d shown in Fig. 3. These will be described in order below.

[0028] The information acquisition unit 43 a acquires traveling situation information from the operation control unit 3 and also acquires a route command value P from the route planning unit 42 , and outputs them to each unit in the speed planning unit 43 .

[0029] The route characteristic point setting unit 43b sets characteristic points on the route command value P, such as peak points of curvature and peak points of the distance differential value of curvature, based on the route command value P acquired from the information acquisition unit 43a. Here, the route characteristic points set by the route characteristic point setting unit 43b may be points where the curvature is zero or start points or end points of the route command value P, and the definition of the route characteristic points is not limited.

[0030] The traveling speed generation unit 43c generates a speed command value when the vehicle travels along the route command value P based on the traveling condition information and the route command value P from the information acquisition unit 43a, and route characteristic points such as the peak point of curvature from the route characteristic point setting unit 43b.

[0031] The information output unit 43d outputs the speed command value from the traveling speed generation unit 43c to the information output unit 44.

[0032] <Processing of the route characteristic point setting unit 43b> Next, route characteristic points that are generated moment by moment while traveling along the route shown in FIG. 4 will be described with reference to FIGS. 5A and 5B.

[0033] FIG. 4 is a plan view of a travel route along which the host vehicle V travels, and illustrates an example of a route command value P set within a travelable area R of the host vehicle V at a certain time. This travelable area R includes the area point H , end point N exists, beginning Define the section up to point H as a straight path S, beginning From point H end Define the section up to point N as curve C, end The section from point N onwards is defined as straight road M.

[0034] FIG. 5A shows an example of the curvature and distance differential value of the curvature of a travel route in which a curve C in the travel route in FIG. 4 has a transition curve section and a steady curve section. beginning After point H, the curvature changes to a constant value. Points U ,point After U, the curvature changes from a constant value. Points T exists ,point U and dotsDefine T as the peak point of curvature. beginning Point H? Raten The section up to U ,point From T end The section up to point N is a transition curve section where the curvature changes linearly, and the distance differential value of the curvature is a constant value, so there is no peak point of the distance differential value of the curvature. beginning point H and dots The midpoint Q of U ,point T and end The midpoint Z of point N is defined as the peak point of the distance differential value of the curvature.

[0035] FIG. 5B is an example of the curvature and distance differential value of the curvature of a travel route in which a transition curve section is included in the curve C of the travel route in FIG. 4. In FIG. 5B, there is a peak point K of the curvature, beginning The section from point H to the peak point K of the curvature and the section from the peak point K to the end The section up to point N is a transition curve section where the curvature changes nonlinearly, and points W and F where the distance differential value of the curvature in each transition curve section reaches a peak are defined as the peak points of the distance differential value of the curvature.

[0036] <Example of processing by the speed planning unit 43> Next, with reference to FIGS. 6 to 7C, the speed command values ​​generated moment by moment by the speed planning unit 43 when the host vehicle V is traveling along the travel route of FIG. 4 will be described.

[0037] FIG. 6 is a flowchart of the speed planning unit 43 according to the first embodiment.

[0038] First, in step S1, the information acquisition unit 43a of the speed planning unit 43 acquires the traveling situation information from the information acquisition unit 41, and acquires the route command value P from the route planning unit .

[0039] Next, in step S2, the route characteristic point setting unit 43b of the speed planning unit 43 sets route characteristic points such as a peak point of curvature on the route command value P (hereinafter referred to as a "first route characteristic point") and a peak point of a distance differential value of the curvature (hereinafter referred to as a "second route characteristic point") based on the driving situation information acquired in step S1 and the route command value P.

[0040] In step S31, the traveling speed generation unit 43c of the speed planning unit 43 generates a speed command value that keeps the longitudinal acceleration occurring when traveling along the route command value P within a specified value, based on the traveling condition information and route command value P acquired in step S1, and the route characteristic points set in step S2.

[0041] 7A shows an example of a graph of the distance axis of (b) vehicle speed, (c) longitudinal acceleration, (d) lateral acceleration, (e) longitudinal jerk, and (f) lateral jerk, and a diagram of (g) longitudinal acceleration and lateral acceleration, which occur when the host vehicle V travels at a constant speed (dashed line) and when the host vehicle V travels at the speed command value generated in step S31 (solid line), and the (a) curvature of the path command value P in FIG. 4. The solid line in FIG. 7A (when the speed command value in step S31 is used) takes into consideration the linkage between the longitudinal motion and the lateral motion, and also maximizes the (c) longitudinal acceleration within the range of the specified values, by aligning the zero point of the (c) longitudinal acceleration with the peak point of the (a) curvature (first path characteristic point) and further aligning the peak point of the (c) longitudinal acceleration with the peak point of the distance derivative of the (a) curvature (second path characteristic point).

[0042] As can be seen from a comparison of the dashed and solid lines in Figures 7A(d) and (g), Figure 7A illustrates a situation in which, compared to constant speed driving, the ride quality and comfort of the occupants are slightly improved by using the speed command value in step S31, but (d) the lateral acceleration still exceeds the specified value, so further improvement of the speed command value is required.

[0043] In step S32, the traveling speed generating unit 43c of the speed planning unit 43 determines whether or not a physical quantity related to the vehicle behavior occurring when traveling along the route command value P is within a specified value, based on the speed command value generated in step S31. If the physical quantity related to the vehicle behavior is within the specified value (step S32, YES), the process proceeds to step S4, and if the physical quantity related to the vehicle behavior is greater than the specified value (step S32, NO), the process proceeds to step S33.

[0044] In step S33, the traveling speed generation unit 43c of the speed planning unit 43 generates a speed command value such that both the longitudinal acceleration and longitudinal jerk occurring when traveling along the route command value P are within specified values, based on the traveling situation information and route command value P acquired in step S1, the route characteristic points defined in step S2, and the speed command value generated in step S31.

[0045] 7B shows an example of the (a) curvature of the path command value P in FIG. 4 and the physical quantities related to vehicle behavior that occur when the host vehicle V travels with the speed command value generated in step S31 (dashed line) and when the host vehicle V travels with the speed command value generated in step S33 (solid line), and the configuration of the graph is the same as in FIG. 7A. The solid line in FIG. 7B (when the speed command value in step S33 is used) sets the (c) peak point of the longitudinal acceleration as the peak point of the distance derivative of the curvature as in step S31, and then maximizes the (e) longitudinal jerk within a specified value, in order to keep the physical quantities related to the vehicle behavior within specified values.

[0046] As can be seen from a comparison of the dashed lines and solid lines in Figures 7B(d) and (g), Figure 7B illustrates an example of a situation in which the ride quality and comfort of the occupants are further improved by using the speed command value in step S33 compared to when the speed command value in step S31 is used, but the lateral acceleration (d) still exceeds the specified value, so further improvement of the speed command value is required.

[0047] In step S34, the traveling speed generating unit 43c of the speed planning unit 43 determines whether or not a physical quantity related to the vehicle behavior occurring when traveling along the route command value P is within a specified value, based on the speed command value generated in step S33. If the physical quantity related to the vehicle behavior is within the specified value (step S34, YES), the process proceeds to step S4, and if the physical quantity related to the vehicle behavior is greater than the specified value (step S34, NO), the process proceeds to step S35.

[0048] In step S35, the traveling speed generation unit 43c of the speed planning unit 43 generates a speed command value based on the traveling condition information and route command value P acquired in step S1, the route characteristic points set in step S2, and the speed command value generated in step S33, by moving the deceleration start point forward (toward the host vehicle V) if deceleration is occurring, or by moving the acceleration end point backward (away from the host vehicle V) if acceleration is occurring, so that the physical quantities related to the vehicle behavior are within specified values.

[0049] 7C shows an example of the (a) curvature of the path command value P in FIG. 4 and the physical quantities related to vehicle behavior that occur when the host vehicle V travels according to the speed command value generated in step S33 (dashed line) and when the host vehicle V travels according to the speed command value generated in step S35 (solid line), and the graph configuration is the same as in FIG. 7A and FIG. 7B. For the solid line in FIG. 7C (when the speed command value in step S35 is used), in order to keep the physical quantities related to vehicle behavior within specified values, (c) the peak point of the longitudinal acceleration is set to the peak point of the distance derivative of the curvature as in step S31 and step S33, and (e) the longitudinal jerk is maximized within specified values, and then the deceleration start point is set on the straight road S before the connection point between the straight road S and the curve C so that the physical quantities related to vehicle behavior fall within specified values ​​(see the graph of (c) longitudinal acceleration).

[0050] As can be seen from a comparison of the dashed and solid lines in Figures 7C(d) and (g), Figure 7C illustrates an example of a situation in which, by using the speed command value in step S35, not only (c) longitudinal acceleration but also (d) lateral acceleration is within the specified value, thereby ensuring sufficient ride comfort and ease for the occupants.

[0051] In step S4, the information output unit 43d of the speed planning unit 43 outputs the speed command value generated in any one of step S31, step S33, or step S35 to the information output unit 44 of the traveling trajectory generation unit 4. Note that all of the speed command values ​​output in step S4 are capable of keeping physical quantities related to vehicle behavior within specified values, and therefore the traveling control unit 5 receiving the speed command value from the information output unit 44 can control the powertrain system 6, the brake system 7, and the steering system 8 so as to achieve vehicle control that provides a comfortable ride.

[0052] <Another example of processing by the speed planning unit 43> Next, another example of the processing of the speed planning unit 43 will be described with reference to Fig. 8A and Fig. 8B. Fig. 8A and Fig. 8B show another example of the curvature (a) of the route command value P in Fig. 4 and physical quantities related to the vehicle behavior that occurs when the host vehicle V travels at the speed command value generated in the flowchart shown in Fig. 6, and the configuration of the graph is the same as Fig. 7A etc.

[0053] In FIGS. 7A to 7C, the specified value of (b) vehicle speed is constant, but in FIGS. 8A and 8B, the specified value of (b) vehicle speed when traveling around curve C is set to be smaller than that when traveling on straight road S. In this case, under both the conditions of FIG. 8A (when entering curve C) and FIG. 8B (when exiting curve C), the processing up to step S35 in FIG. 6 is performed, thereby further suppressing the vehicle speed when traveling around curve C while keeping the physical quantities related to vehicle behavior, including (b) vehicle speed, within specified values. This makes it possible to travel around curve C at a vehicle speed that provides a comfortable ride, while keeping acceleration and jerk within specified values.

[0054] In this manner, in the speed control of this embodiment illustrated in Figures 7A to 8B, in order to link the longitudinal movement and the lateral movement, the peak point of the longitudinal acceleration is aligned with the peak point of the distance derivative of the curvature, and the zero point of the longitudinal acceleration is aligned with the peak point of the curvature, and the range in which the longitudinal acceleration occurs is gradually expanded until the physical quantities related to the vehicle behavior fall within specified values. This makes it possible to keep the physical quantities related to the vehicle behavior within specified values ​​that do not impair the ride quality and comfort of the occupants while minimizing speed reduction. [Example]

[0055] Next, a vehicle motion control device 2 according to a second embodiment of the present invention will be described with reference to Figures 9 to 10B. Note that a duplicated description of points common to the first embodiment will be omitted.

[0056] Fig. 9 is a flowchart of the speed planning unit 43 of the second embodiment. The flowchart of the speed planning unit 43 of the second embodiment shown here is obtained by adding steps S5 to S7 between step S32, step S4, and step S33 to the flowchart of the speed planning unit 43 of the first embodiment shown in Fig. 6. That is, in the present embodiment, if it is determined in step S32 that the physical quantity based on the speed command value in step S31 is within a specified value, the process proceeds to step S5, and if not, the process proceeds to step S6.

[0057] In step S5, traveling speed generating unit 43c of speed planning unit 43 generates a speed command value after moving the position of the peak point of the longitudinal acceleration forward or backward on the distance axis. Although the determination in step S32 ensures that a certain level of ride comfort is maintained in vehicle control using the speed command value in step S31, in this step, by correcting the speed command value in step S31 to reduce the longitudinal jerk, it becomes possible to achieve vehicle control with a more comfortable ride that further suppresses unstable vehicle behavior.

[0058] Meanwhile, in step S6, traveling speed generation unit 43c of speed planner 43 generates a speed command value after moving the position of the peak point of the longitudinal acceleration forward or backward on the distance axis so that a physical quantity related to vehicle behavior that is greater than a specified value is improved (approaching the specified value). Since it has been determined in step S32 that the speed command value of step S31 is not sufficient to achieve vehicle control with a comfortable ride, the processing of this step corrects the speed command value generated in step S31 to reduce the longitudinal jerk, thereby increasing the possibility of achieving vehicle control with a comfortable ride. Note that even after the processing of this step, there may be cases where the physical quantity related to vehicle behavior cannot be brought within the specified value, and therefore it may be necessary to perform processing (for example, steps S33 and S35 in FIG. 6) to further improve the speed command value.

[0059] Therefore, in step S7, the traveling speed generation unit 43c of the speed planning unit 43 determines whether or not a physical quantity related to the vehicle behavior occurring when traveling along the route command value P is within a specified value, based on the speed command value in step S6. If the physical quantity related to the vehicle behavior is within the specified value (step S7, YES), the process proceeds to step S4, and if the physical quantity related to the vehicle behavior is greater than the specified value (step S7, NO), the process proceeds to step S33. This allows the speed command value in step S6 to be further corrected as necessary.

[0060] 10A shows an example of the (a) curvature of the path command value P in Fig. 4 and the physical quantities related to the vehicle behavior that occur when the host vehicle V travels according to the speed command value generated in step S31 of the first embodiment (dashed line) and when the host vehicle V travels according to the speed command value generated in step S5 of the second embodiment (solid line), and the configuration of the graph is the same as that of Fig. 7A of the first embodiment, etc. The solid line in Fig. 10A shifts the peak point of the (c) longitudinal acceleration closer (toward the host vehicle V) within a range in which the physical quantities related to the vehicle behavior fall within specified values, thereby reducing the jerk in a region where the acceleration is large.

[0061] In this manner, in the speed control of this embodiment illustrated in FIG. 10A, the peak point of the longitudinal acceleration is set closer or further away within a range in which the physical quantity related to the vehicle behavior falls within a specified value, thereby reducing the jerk in a region where the acceleration is large, thereby suppressing unstable vehicle behavior and improving the ride comfort for the occupants.

[0062] 10B shows an example of the curvature (a) of the path command value P in FIG. 4 and physical quantities related to vehicle behavior that occur when the host vehicle V travels with the speed command value generated in step S31 of the first embodiment (dashed line) and when the host vehicle V travels with the speed command value generated in step S6 of the second embodiment (solid line), and the configuration of the graph is the same as that of FIG. 7A of the first embodiment, etc. The solid line in FIG. 10B positions the peak point of the longitudinal acceleration toward the back (in the direction away from the host vehicle V) so that the physical quantities related to the vehicle behavior fall within specified values.

[0063] In this manner, in the speed control of this embodiment illustrated in FIG. 10B, the peak point of the longitudinal acceleration is shifted forward or backward so that the physical quantity related to the vehicle behavior falls within a specified value, thereby linking the longitudinal movement and the lateral movement and keeping the physical quantity related to the vehicle behavior within a specified value, thereby improving the ride comfort for the occupants. [Example]

[0064] Next, a vehicle motion control device 2 according to a third embodiment of the present invention will be described with reference to Figures 11 and 12. Note that a duplicated description of points common to the first and second embodiments will be omitted.

[0065] 11 is a flowchart of the speed planning unit 43 of the third embodiment. The flowchart of the speed planning unit 43 of the third embodiment shown here is obtained by adding step S8 between step S32 and step S5 to the flowchart of the speed planning unit 43 of the second embodiment shown in FIG.

[0066] In step S8, the traveling speed generation unit 43c of the speed planning unit 43 generates a speed command value that does not set the longitudinal acceleration at the peak point of the curvature to zero when the physical quantity related to the vehicle behavior occurring in the host vehicle V traveling based on the speed command value of step S31 is within a specified value.

[0067] 12 shows an example of (a) the curvature of the path command value P in FIG. 4 and physical quantities related to vehicle behavior that occur when the host vehicle V travels according to the speed command value generated in step S8, and the graph configuration is the same as that of FIG. 7A in the first embodiment, etc. In FIG. 12, (c) the longitudinal acceleration and (e) the longitudinal jerk are maximized within a range in which the physical quantities related to the vehicle behavior fall within specified values.

[0068] In this way, in the speed control of this embodiment illustrated in FIG. 12, the longitudinal acceleration and longitudinal jerk are maximized within a range in which the physical quantities related to the vehicle behavior fall within specified values, thereby making it possible to suppress the occurrence of vibrations and reductions in vehicle speed due to unnecessary acceleration and deceleration, thereby improving the ride comfort for occupants and shortening travel time. [Example]

[0069] Next, a vehicle motion control device 2 according to a fourth embodiment of the present invention will be described with reference to Fig. 13. Note that overlapping explanations of points common to the first to third embodiments will be omitted.

[0070] Fig. 13 is a flowchart of the speed planning unit 43 according to the fourth embodiment. The flowchart of this embodiment shown here is obtained by adding step S9 between step S1 and step S2 to the flowchart of the first embodiment shown in Fig. 6, the flowchart of the second embodiment shown in Fig. 9, and the flowchart of the third embodiment shown in Fig. 11.

[0071] In step S9, the speed planning unit 43 determines whether or not to generate a speed command value based on a flag generated by a controller (for example, the traffic management unit 3) higher than the speed planning unit 43. If the flag indicates that processing is prohibited (step S9, YES), the processing ends and no speed command value is generated. On the other hand, if the flag indicates that processing is permitted (step S9, NO), the processing proceeds to step 2 and subsequent steps, and a desired speed command value is generated.

[0072] As a result, in an emergency such as when avoiding a preceding vehicle that has suddenly stopped, if the upper controller prohibits the generation of a speed command value that improves ride comfort, the upper controller's speed control will be switched to one that emphasizes avoidance performance, which will result in a deterioration in ride comfort but will avoid a rear-end collision with the preceding vehicle, thereby improving safety. [Example]

[0073] Next, a vehicle motion control device 2 according to a fifth embodiment of the present invention will be described with reference to Fig. 14. Note that a duplicated description of points common to the first to fourth embodiments will be omitted.

[0074] Fig. 14 is a functional block diagram of the speed planning unit 43 of the fifth embodiment. The speed planning unit 43 of the fifth embodiment shown here is obtained by changing the travel speed generation unit 43c of the speed planning unit 43 of the first embodiment shown in Fig. 3 to a travel speed candidate generation unit 43e and further adding a travel speed selection unit 43f.

[0075] The candidate traveling speed generating unit 43e generates a plurality of speed command values ​​based on the traveling condition information acquired by the information acquiring unit 43a and the route command value P, such that the physical quantities related to the vehicle behavior occurring when traveling along the route command value P are within specified values, and outputs the generated speed command values ​​to the traveling speed selecting unit 43f.

[0076] The driving speed selection unit 43f selects one as a speed command value based on the current driving mode (shortest time mode, economy mode, etc.) indicated by the driving condition information from the information acquisition unit 43a and multiple speed command value candidates from the driving speed candidate generation unit 43e, and the information output unit 43d outputs it to the driving control unit 5.

[0077] For example, when the traveling condition information indicates the shortest time mode, the traveling speed candidate generating unit 43e selects the speed command value candidate with the shortest travel time from among the multiple speed command value candidates generated, and when the traveling condition information indicates the economy mode, the traveling speed candidate generating unit 43f selects the speed command value candidate with the smallest energy consumption from among the multiple speed command value candidates. That is, the traveling speed selecting unit 43f selects the speed command value with the shortest travel time from among the multiple speed command value candidates, or selects the speed command value with the smallest energy consumption from among the multiple speed command value candidates.

[0078] Furthermore, in order to enable the traveling speed candidate generation unit 43e to generate a plurality of speed command values, the specified value setting unit 31 of the operation management unit 3 of this embodiment may set a plurality of specified values ​​based on the mass, size, and arrangement of the occupants and cargo of the vehicle, and the state of the route along which the vehicle travels. This allows the traveling speed candidate generation unit 43e to generate a plurality of speed command values ​​according to the number of occupants, seating positions, etc., so that the traveling speed selection unit 43f can select a speed command value according to the number of occupants, etc., thereby further improving the ride comfort when the vehicle is traveling.

[0079] As described above, the vehicle motion control device of the fifth embodiment not only provides the same effects as those of the first to fourth embodiments, but also makes it possible to control vehicle motion in accordance with the selection of the driving mode and the vehicle installation status.

[0080] The present invention is not limited to the above-described embodiments, but includes various modifications. For example, the above-described embodiments have been specifically described to clearly explain the present invention, and the present invention is not necessarily limited to those having all of the described configurations. Furthermore, a portion of the configuration of one embodiment can be replaced with a portion of the configuration of another embodiment. Furthermore, a portion of the configuration of another embodiment can be added to a portion of the configuration of one embodiment. Furthermore, a portion of the configuration of each embodiment can be deleted, and a portion of another configuration can be added or replaced with a portion of another configuration. [Explanation of symbols]

[0081] 1. In-vehicle systems 11. External communication device 12 GNSS 13 Map information storage unit 14 Sensors 15 HMI units 2 Vehicle motion control device 3. Operation Control Unit 31 Default value setting section 4. Trajectory generation unit 41 Information Acquisition Department 42 Route Planning Section 43 Speed ​​Planning Department 43a Information acquisition section 43b Route feature point setting unit 43c Travel speed generating unit 43d Information output section 43e Traveling speed candidate generation unit 43f Travel speed selection section 44 Information output section 5. Driving control unit 6 Powertrain System 7. Brake system 8. Steering System

Claims

1. a route planning unit that generates a route along which the vehicle will travel; a specified value setting unit that sets upper limits of longitudinal acceleration, lateral acceleration, longitudinal jerk, and lateral jerk of the vehicle when traveling along the route; a route characteristic point setting unit that sets a start point, an end point, a point of zero curvature, a peak point of curvature, and a peak point of a distance differential value of the curvature of the route as route characteristic points; a travel speed generating unit that generates a speed command value for the vehicle to travel on the route based on the route, the upper limit value, and the route characteristic points; a vehicle motion control device characterized in that the traveling speed generation unit aligns a zero point of longitudinal acceleration with a peak point of the curvature of the route, aligns a peak point of longitudinal acceleration with a peak point of a distance differential value of the curvature, and generates the speed command value so as to maximize longitudinal acceleration within the upper limit value between a start point and an end point of a curve section of the route.

2. a route planning unit that generates a route along which the vehicle will travel; a specified value setting unit that sets upper limits of longitudinal acceleration, lateral acceleration, longitudinal jerk, and lateral jerk of the vehicle when traveling along the route; a route characteristic point setting unit that sets a start point, an end point, a point of zero curvature, a peak point of curvature, and a peak point of a distance differential value of the curvature of the route as route characteristic points; a travel speed generating unit that generates a speed command value for the vehicle to travel on the route based on the route, the upper limit value, and the route characteristic points; the traveling speed generating unit generates the speed command value by aligning a zero point of a longitudinal acceleration with a peak point of a curvature of the route and by aligning a peak point of the longitudinal acceleration with a peak point of a distance differential value of the curvature, the traveling speed generating unit generates a speed command value that maximizes longitudinal acceleration and longitudinal jerk within their respective upper limit values ​​between a start point and an end point of a curve section of the route; When the lateral acceleration or lateral jerk is outside its respective upper limit value with the speed command value, a speed command value is generated with the deceleration start point closer to the vehicle on the distance axis or the acceleration end point further away from the vehicle on the distance axis.

3. a route planning unit that generates a route along which the vehicle will travel; a specified value setting unit that sets upper limits of longitudinal acceleration, lateral acceleration, longitudinal jerk, and lateral jerk of the vehicle when traveling along the route; a route characteristic point setting unit that sets a start point, an end point, a point of zero curvature, a peak point of curvature, and a peak point of a distance differential value of the curvature of the route as route characteristic points; a travel speed generating unit that generates a speed command value for the vehicle to travel on the route based on the route, the upper limit value, and the route characteristic points; the traveling speed generating unit generates the speed command value by aligning a zero point of a longitudinal acceleration with a peak point of a curvature of the route and by aligning a peak point of the longitudinal acceleration with a peak point of a distance differential value of the curvature, the traveling speed generating unit generates a speed command value that maximizes longitudinal acceleration and longitudinal jerk within their respective upper limit values ​​between a start point and an end point of a curve section of the route; A vehicle motion control device characterized in that a speed command value is generated by positioning the peak point of longitudinal acceleration closer to or further away from the vehicle on a distance axis within a range in which the lateral acceleration and lateral jerk are within their respective upper limit values ​​with the speed command value.

4. a route planning unit that generates a route along which the vehicle will travel; a specified value setting unit that sets upper limits of longitudinal acceleration, lateral acceleration, longitudinal jerk, and lateral jerk of the vehicle when traveling along the route; a route characteristic point setting unit that sets a start point, an end point, a point of zero curvature, a peak point of curvature, and a peak point of a distance differential value of the curvature of the route as route characteristic points; a travel speed generating unit that generates a speed command value for the vehicle to travel on the route based on the route, the upper limit value, and the route characteristic points; the traveling speed generating unit generates the speed command value by aligning a zero point of a longitudinal acceleration with a peak point of a curvature of the route and by aligning a peak point of the longitudinal acceleration with a peak point of a distance differential value of the curvature, the traveling speed generating unit generates a speed command value that maximizes longitudinal acceleration and longitudinal jerk within their respective upper limit values ​​between a start point and an end point of a curve section of the route; A vehicle motion control device characterized in that, when the lateral acceleration and lateral jerk are within their respective upper limit values ​​at the speed command value, the zero point of the longitudinal acceleration is not aligned with the peak point of the curvature.

5. The vehicle motion control device according to any one of claims 1 to 4, The traveling speed generation unit generating the speed command value when a flag output from the upper controller indicates that processing is permitted; A vehicle motion control device characterized in that the speed command value is not generated when a flag output from a host controller indicates that processing is prohibited.

6. a route planning step for generating a route along which the vehicle will travel; a specified value setting step of setting upper limits of longitudinal acceleration, lateral acceleration, longitudinal jerk, and lateral jerk of the vehicle when traveling along the route; a route characteristic point setting step of setting the start point, end point, zero curvature point, peak curvature point, and peak curvature distance differential value point of the route as route characteristic points; a travel speed generating step of generating a speed command value for the vehicle to travel on the route based on the route, the upper limit value, and the route characteristic points; a speed command value that maximizes longitudinal acceleration within the upper limit between a start point and an end point of a curved section of the route by aligning a zero point of longitudinal acceleration with a peak point of curvature of the route and a peak point of longitudinal acceleration with a peak point of a distance derivative of the curvature, the speed command value being generated.

Images