Vehicle travel support device and vehicle travel support method

Abstract

To provide a vehicle travel support device and vehicle travel support method capable of reducing a jerk occurring in an own vehicle and a change rate of the jerk when controlling a distance between the own vehicle and an object, and a speed of the own vehicle, and capable of suppressing an increase in travel distance.SOLUTION: A vehicle travel support device: sets a target speed of an own vehicle and a target distance of a distance between the own vehicle and an object; performs four-stage filter processing consisting of a first filter, a second filter, a third filter, and a fourth filter on the target distance in a virtual time to calculate a distance plan that is a transient target distance at each future time; calculates a speed plan that is a transient target speed at each future time on the basis of the distance plan and the target speed; calculates an acceleration command value of the own vehicle on the basis of at least the speed plan; and controls the own vehicle on the basis of the acceleration command value.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] This disclosure relates to a vehicle driving support device and a vehicle driving support method.

Background Art

[0002] Conventionally, a following control device that recognizes other vehicles in front of the host vehicle, maintains a vehicle-to-vehicle distance based on the driving vehicle speed, and performs constant-speed driving at a set vehicle speed when there are no other vehicles has been put into practical use. In the technology of Patent Document 1, the trajectory generation unit plans a target speed as shown in FIG. 12 of Patent Document 1 and controls the driving control unit to follow the speed pattern.

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] In a conventional vehicle control system, since the planned target speed is composed of uniformly accelerated motion, sudden changes in jerk and jerk change rate occur at the start of acceleration and deceleration, etc., resulting in a deterioration of the riding comfort. Further, if the vehicle control unit controls so that the sudden change in jerk and the jerk change rate do not change suddenly, a deviation from the original driving plan occurs, and there is a possibility of approaching the preceding vehicle excessively.

[0005] Therefore, an object of the present disclosure is to provide a vehicle driving support device and a vehicle driving support method that can reduce the jerk and jerk change rate generated in the host vehicle and suppress an increase in the driving distance when controlling the distance between the host vehicle and an object and the speed of the host vehicle.

Means for Solving the Problems

[0006] The vehicle driving support device according to the present disclosure includes an information acquisition unit that acquires information on the host vehicle and information on an object existing around the host vehicle; a target determination unit that sets a target speed of the host vehicle and a target distance that is a target value of the distance between the host vehicle and the object based on the information on the host vehicle and the information on the object; a plan generation unit that calculates a distance plan, which is a transient target distance at each future time until a reach time when the distance reaches the target distance and the speed of the host vehicle reaches the target speed, based on the target distance, and calculates a speed plan, which is a transient target speed at each future time, based on the distance plan and the target speed; and a vehicle control unit that calculates an acceleration command value of the host vehicle based on at least the speed plan and controls the host vehicle based on the acceleration command value. The plan generation unit calculates the distance plan by performing four-stage filter processing including a first filter, a second filter, a third filter, and a fourth filter on the target distance at virtual time representing each future time from the present to the reach time.

[0007] The vehicle driving support method according to the present disclosure includes an information acquisition step of acquiring information on the host vehicle and information on an object existing around the host vehicle; a target determination step of setting a target speed of the host vehicle and a target distance that is a target value of the distance between the host vehicle and the object based on the information on the host vehicle and the information on the object; a plan generation step of calculating a distance plan, which is a transient target distance at each future time until a reach time when the distance reaches the target distance and the speed of the host vehicle reaches the target speed, based on the target distance, and calculating a speed plan, which is a transient target speed at each future time, based on the distance plan and the target speed; and a vehicle control step of calculating an acceleration command value of the host vehicle based on at least the speed plan and controlling the host vehicle based on the acceleration command value. In the said plan generation step, at virtual times representing each future time from the present to the said arrival time, a four-stage filtering process consisting of a first filter, a second filter, a third filter, and a fourth filter is performed on the said target distance to calculate the said distance plan.

Advantages of the Invention

[0008] According to the vehicle driving support device and the vehicle driving support method according to the present disclosure, by using a four-stage filtering process, it is possible to reduce the jerk and the jerk change rate generated in the host vehicle during acceleration and deceleration until reaching the target distance and the target speed, and improve the riding comfort of the host vehicle. In addition, by managing the arrival time, it is possible to prevent an increase in the driving distance until reaching the target distance and the target speed.

Brief Description of the Drawings

[0009]

Figure 1

Figure 2

Figure 3

Figure 4

Figure 5

Figure 6

Figure 7

Figure 8

Figure 9

Figure 10

Figure 11

Figure 12

Figure 13

Figure 14

Figure 15

Figure 16

Figure 17

Figure 18

Mode for Carrying Out the Invention

[0010] 1. Embodiment 1 The vehicle driving support device 50 according to Embodiment 1 will be described with reference to the drawings. In the present embodiment, the vehicle driving support device 50 is provided in the host vehicle.

[0011] As shown in FIG. 1, the host vehicle includes a surrounding monitoring device 31, a position detection device 32, a vehicle state detection device 33, a map information database 34, a wireless communication device 35, a vehicle driving support device 50, a drive control device 36, a power unit 8, an electric steering device 7, an electric brake device 9, and a human interface device 37, etc.

[0012] The peripheral monitoring device 31 is a device such as a camera or a radar that monitors the periphery of the vehicle. As the radar, a millimeter-wave radar, a lidar, an ultrasonic radar, etc. are used. The wireless communication device 35 performs wireless communication with a base station using a cellular wireless communication standard such as 4G or 5G. The wireless communication device 35 performs wireless communication with a roadside unit and surrounding vehicles, etc.

[0013] The position detection device 32 is a device that detects the current position (latitude, longitude, altitude) of the host vehicle, and a GPS antenna or the like that receives a signal output from an artificial satellite such as GNSS (Global Navigation Satellite System) is used. Note that various methods such as a map matching method, a dead reckoning method, and a method using detection information around the host vehicle may be used for detecting the current position of the host vehicle.

[0014] The map information database 34 stores road information such as road shapes (for example, the number of lanes, the position of each lane, the shape of each lane, the type of each lane, road type, speed limit, intersection shape, etc.), road signs (speed limit signs and their speed limits, stop signs, etc.), road markings (stop lines, crosswalks, etc.), toll booths (the entrance position of the toll booth, the passing speed of the toll booth, etc.), traffic lights, etc. The map information database 34 is mainly composed of a storage device. Note that the map information database 34 may be provided in an external server outside the vehicle connected to a network, and the vehicle driving support device 50 may acquire necessary road information from the external server via the wireless communication device 35.

[0015] As the drive control device 36, a power control device, a brake control device, an automatic steering control device, a light control device, etc. are provided. The power control device controls the output of a power unit 8 such as an internal combustion engine and a motor. The brake control device controls the braking operation of an electric brake device 9. The automatic steering control device controls an electric steering device 7. The light control device controls a direction indicator, a hazard lamp, etc.

[0016] The vehicle state detection device 33 is a detection device that detects the state of the host vehicle, such as the driving state and running state of the host vehicle. In the present embodiment, the vehicle state detection device 33 detects, as the running state of the host vehicle, the speed, acceleration, yaw rate, steering angle, lateral acceleration, etc. of the host vehicle. For example, as the vehicle state detection device 33, a speed sensor that detects the rotational speed of the wheels, an acceleration sensor, an angular velocity sensor, a steering angle sensor, etc. are provided.

[0017] As the driving state of the host vehicle, acceleration / deceleration operations, steering angle operations, and lane change operations by the driver are detected. For example, as the vehicle state detection device 33, an accelerator position sensor, a brake position sensor, a steering angle sensor (steering wheel angle sensor), a steering torque sensor, a direction indicator position switch, etc. are provided.

[0018] The human interface device 37 is a device that receives the driver's input, such as a speaker, a display screen, and an input device, and transmits information to the driver.

[0019] 1-1. Vehicle Travel Support Device 50 The vehicle travel support device 50 includes processing units such as an information acquisition unit 51, a target determination unit 52, a plan generation unit 53, and a vehicle control unit 54. Each process of the vehicle travel support device 50 is realized by a processing circuit provided in the vehicle travel support device 50. Specifically, as shown in FIG. 2, the vehicle travel support device 50 includes an arithmetic processing device 90 such as a CPU (Central Processing Unit), a storage device 91, an input / output device 92 that inputs / outputs external signals to / from the arithmetic processing device 90, etc.

[0020] As the arithmetic processing unit 90, an ASIC (Application Specific Integrated Circuit), an IC (Integrated Circuit), a DSP (Digital Signal Processor), an FPGA (Field Programmable Gate Array), a GPU (Graphics Processing Unit), an AI (Artificial Intelligence) chip, various logic circuits, various signal processing circuits, etc. may be provided. Also, as the arithmetic processing unit 90, a plurality of the same type or different types may be provided, and each process may be executed in a shared manner. As the storage device 91, various storage devices such as a RAM (Random Access Memory), a ROM (Read Only Memory), a flash memory, an EEPROM (Electrically Erasable Programmable Read Only Memory), and a hard disk are used.

[0021] The input / output device 92 is provided with a communication device, an A / D converter, an input / output port, a drive circuit, etc. The input / output device 92 is connected to a peripheral monitoring device 31, a position detection device 32, a vehicle state detection device 33, a map information database 34, a wireless communication device 35, a drive control device 36, a human interface device 37, etc., and communicates with these devices.

[0022] Then, each process such as each of the processing units 51 to 54 included in the vehicle driving support device 50 is realized by the arithmetic processing unit 90 executing software (program) stored in the storage device 91 and cooperating with other hardware of the vehicle driving support device 50 such as the storage device 91 and the input / output device 92. Note that setting data such as time constants used by each of the processing units 51 to 54 is stored in the storage device 91 such as an EEPROM.

[0023] 1-1-1. Information acquisition unit 51 The information acquisition unit 51 acquires information on the host vehicle and information on an object existing around the host vehicle.

[0024] For example, as shown in FIG. 3, the object is set to another vehicle (hereinafter referred to as the target vehicle) traveling in front of or behind the driving lane on which the host vehicle is traveling. According to this configuration, the excessive jerk and jerk change rate can be suppressed in the acceleration and deceleration when the host vehicle follows the preceding vehicle or in the acceleration and deceleration when ensuring the inter-vehicle distance between the host vehicle and the following vehicle by the plan generation unit 53 described later.

[0025] Also, as shown in FIG. 4, the object is set to another vehicle (target vehicle) traveling in the lane to which the host vehicle is moving. In this case, there are cases such as when changing lanes, merging lanes, and branching lanes. According to this configuration, the excessive jerk and jerk change rate can be suppressed in the acceleration and deceleration when ensuring the inter-vehicle distance between the host vehicle and another vehicle traveling in the lane to which the host vehicle is moving by the plan generation unit 53 described later.

[0026] In the present embodiment, the information acquisition unit 51 acquires at least the speed v of the host vehicle, the speed vtgt of the target vehicle, the distance d that is the distance between the host vehicle and the target vehicle, and the relative speed vrel of the target vehicle with respect to the host vehicle.

[0027] The information acquisition unit 51 acquires the driving state of the host vehicle as information of the host vehicle. In the present embodiment, the information acquisition unit 51 acquires the position, moving direction, speed, acceleration, etc. of the host vehicle based on the position information of the host vehicle acquired from the position detection device 32 and the host vehicle state acquired from the vehicle state detection device 33.

[0028] Based on the position information of the host vehicle acquired from the position detection device 32, the information acquisition unit 51 acquires road information around the host vehicle from the map information database 34. The road information to be acquired includes road shape (e.g., number of lanes, position of each lane, shape of each lane, type of each lane, road type, speed limit, shape of intersection, etc.), road signs (speed limit sign and its speed limit, stop sign, etc.), road markings (stop line, crosswalk, etc.), toll gate information (entrance position of toll gate, passing speed of toll gate, etc.), road information such as traffic lights, etc. The shape of each lane includes the center position of the lane, the width of the lane, the curvature of the lane, etc. The shape of the lane is set at each point along the front-rear direction of the lane. The type of each lane includes the main lane, the merging lane that merges into the main lane, etc. Also, the shape of the lane includes the start position of the merging lane, the end position of the merging lane, and the length of the merging lane.

[0029] Also, based on the detection information of lane dividing lines such as white lines and road shoulders acquired from the surrounding monitoring device 31, the information acquisition unit 51 detects the shape and type of road lane dividing lines, etc., and based on the detected shape and type of road lane dividing lines, etc., determines the shape and position of each lane, the number of lanes, the type of each lane, etc. The shape of each lane includes the center position of the lane, the width of the lane, the curvature of the lane, etc. The type of each lane includes the main lane, the merging lane, etc.

[0030] Also, the information acquisition unit 51 acquires road signs, road markings, traffic lights, and toll gate information based on the detection information acquired from the surrounding monitoring device 31. The information acquisition unit 51 may acquire the current state of traffic lights, etc. from the outside via wireless communication.

[0031] The information acquisition unit 51 acquires information about other vehicles around the host vehicle. In the present embodiment, based on the detection information acquired from the surrounding monitoring device 31 and the position information of the host vehicle acquired from the position detection device 32, the information acquisition unit 51 acquires the relative position, relative speed, and distance of other vehicles with respect to the host vehicle, as well as the position, moving direction, speed, and acceleration of other vehicles, etc. Also, in addition to other vehicles, the information acquisition unit 51 also acquires information such as obstacles, pedestrians, and traffic regulations such as lane restrictions.

[0032] The information acquisition unit 51 may acquire, by communication from outside the host vehicle, the driving state of other vehicles (the position, moving direction, speed, etc. of other vehicles), as well as road information (lane information, etc.) and traffic information (obstacles, congestion level, etc.) around the host vehicle. For example, the information acquisition unit 51 may acquire the driving state of other vehicles, as well as road information and traffic information around the host vehicle, by wireless communication or the like from other vehicles or a server to which other vehicles have uploaded information. Further, the driving state of other vehicles, as well as road information and traffic information, in the monitoring area may be acquired by wireless communication or the like from a roadside device such as a camera that monitors the road conditions and the like.

[0033] The information acquisition unit 51 acquires lane information corresponding to the lane in which the host vehicle is traveling based on the position of the host vehicle. Further, the information acquisition unit 51 acquires lane information corresponding to the lane in which each other vehicle is traveling based on the position of each other vehicle. The acquired lane information includes the shape, position, and type of the lane, as well as the lane information of the surrounding lanes.

[0034] 1-1-2. Target determination unit 52 The target determination unit 52 sets the target speed v* of the host vehicle and the target distance d*, which is the target value of the distance between the host vehicle and the target object, based on the information of the host vehicle and the information of the target object (in this example, the target vehicle).

[0035] In the present embodiment, the target determination unit 52 sets the target speed v* of the host vehicle based on the speed vtgt of the target object (in this example, the target vehicle). For example, as shown in the following formula, the target determination unit 52 sets the target speed v* of the host vehicle to the speed vtgt of the target vehicle. For example, the speed vtgt of the target vehicle is calculated by adding the relative speed vrel of the target vehicle with respect to the host vehicle to the speed v of the host vehicle.

Equation

[0036] In this embodiment, the target determination unit 52 sets the target distance d* based on the speed vtgt of the target vehicle. When the target vehicle is the preceding vehicle of the host vehicle or the preceding vehicle traveling in the lane of the destination of the host vehicle, Equation (2) is used, and the target distance d* becomes a positive value. When the target vehicle is the following vehicle of the host vehicle or the following vehicle traveling in the lane of the destination of the host vehicle, Equation (3) is used, and the target distance d* becomes a negative value.

Number

Number

[0037] Here, Thw is the inter-vehicle time, which is multiplied by the speed vtgt of the target vehicle, and a distance component proportional to the speed vtgt of the target vehicle is calculated. For example, the inter-vehicle time Thw is set to 1 to 2 seconds and may be changed by the driver via the human interface device 37. Dstop is the target distance when the target vehicle is stopped. For example, a predetermined value is set for Dstop and may be changed by the driver via the human interface device 37.

[0038] 1-1-3. Planning Generation Unit 53 The planning generation unit 53 calculates a distance plan dplan(t), which is a transient target distance at each future time t until the arrival time Trch when the distance d reaches the target distance d* and the speed v of the host vehicle reaches the target speed v*, based on the target distance d*. Then, based on the distance plan dplan(t) and the target speed v*, the planning generation unit 53 calculates a speed plan vplan(t), which is a transient target speed at each future time t.

[0039] The planning generation unit 53 performs four-stage filter processing Fd consisting of the first filter F1d, the second filter F2d, the third filter F3d, and the fourth filter F4d on the target distance d* at the virtual time representing each future time t from the present to the arrival time Trch, and calculates a distance plan dplan(t), which is a transient target distance at each future time t.

[0040] According to this configuration, by using the four-stage filter process Fd, it is possible to reduce the jerk and the jerk change rate generated in the host vehicle during acceleration and deceleration until reaching the target distance d* and the target speed v*, and improve the ride comfort of the host vehicle. Also, by managing the arrival time Trch, it is possible to prevent an increase in the travel distance until reaching the target distance d* and the target speed v*.

[0041] In the present embodiment, as shown in Expressions (4) to (6), the plan generation unit 53, at the current time t = 0, adds, to the input value din of the four-stage filter process that changes stepwise to 0 from the value obtained by subtracting the target distance d* from the initial distance d0, the four-stage filter value obtained by performing the four-stage filter process Fd in virtual time and the target distance d*, and calculates the distance plan dplan(t), which is the transient target distance at each future time t. The initial distance d0 is set to the actual distance at the current time t = 0.

[0042] As shown in Expression (4), the input value din of the four-stage filter process changes stepwise to 0 from the value obtained by subtracting the target distance d* from the initial distance d0 at the current time t = 0.

Equation

[0043] The transfer function Fd(s) of the four-stage filter process is represented by Expression (5). In the present embodiment, each of the first filter F1d, the second filter F2d, the third filter F3d, and the fourth filter F4d is a moving average filter. Each of the first time constant τ1d of the first filter F1d, the second time constant τ2d of the second filter F2d, the third time constant τ3d of the third filter F3d, and the fourth time constant τ4d of the fourth filter F4d is a moving average time. Here, s is a Laplace operator.

Equation

[0044] Then, as shown in Equation (6), the plan generation unit 53 adds the target distance d* to the value obtained by performing the four-stage filter process Fd on the input value din of the four-stage filter process, and calculates the distance plan dplan(t), which is the transient target distance at each time t.

Equation

[0045] Here, L -1 represents the inverse Laplace transform. Note that in the actual four-stage filter process, a discretized equation is used.

[0046] In the present embodiment, as shown in Equation (7), the plan generation unit 53 subtracts the time derivative value of the output value of the four-stage filter process from the target velocity v*, and calculates the velocity plan vplan(t), which is the transient target velocity at each future time t. Instead of the time derivative value of the output value of the four-stage filter process, the time derivative value of the distance plan dplan(t) may be used.

Equation

[0047] The planning generation unit 53 calculates the time derivative value of the initial output value of the four-stage filter process at the current time t = 0 such that the speed plan vplan(0) at the current time t = 0 matches the speed v of the current host vehicle, calculates the initial output value of the four-stage filter process at the current time t = 0 such that the distance plan dplan(0) at the current time t = 0 of the four stages matches the initial distance d0, and at the current time t = 0, sets the initial internal calculation values of each filter of the four-stage filter process such that the time derivative value of the output value of the four-stage filter process matches the time derivative value of the initial output value and the output value of the four-stage filter process matches the initial output value. When the calculation formula of the speed plan vplan(t) in Equation (7) is used, the value obtained by subtracting the speed v of the current host vehicle from the target speed v* is calculated as the time derivative value of the initial output value of the four-stage filter process. When the calculation formula of the distance plan dplan(t) in Equation (6) is used, the value obtained by subtracting the target distance d* from the initial distance d0 is calculated as the initial output value of the four-stage filter process.

[0048] Note that other mathematically equivalent calculation methods may be used. For example, at the current time t = 0, the planning generation unit 53 may perform a four-stage filter process Fd in virtual time on an input value that changes stepwise from the initial distance d0 to the target distance d*, and calculate a distance plan dplan(t) that is a transient target distance. In this case, the planning generation unit 53 calculates the speed plan vplan(t) by subtracting the time derivative value of the distance plan dplan(t), which is the output value of the four-stage filter process, from the target speed v*.

[0049] Alternatively, at the current time t = 0, the planning generation unit 53 adds the four-stage filter value obtained by performing the four-stage filter process Fd in virtual time on an input value that changes stepwise from 0 to the value obtained by subtracting the initial distance d0 from the target distance d* to the initial distance d0, and calculates a distance plan dplan(t) that is a transient target distance at each future time t. In this case, the planning generation unit 53 calculates the speed plan vplan(t) by subtracting the time derivative value of the output value of the four-stage filter process or the distance plan dplan(t) from the target speed v*.

[0050] <Explanation of the Operation of the Four-Stage Filter Processing> Figures 5 to 8 show the behavior of each value before and after the filter processing from the first filter to the fourth filter. At the current time t = 0, the target distance d* is decreasing stepwise from 40 m to 20 m. The speed v of the host vehicle at the current time t = 0 is consistent with the target speed v*. The first time constant τ1d is set to 8 seconds, the second time constant τ2d is set to 4 seconds, the third time constant τ3d is set to 2 seconds, and the fourth time constant τ4d is set to 1 second.

[0051] Figure 5 shows the behavior before and after the processing of the first filter F1d. The horizontal axis is the virtual time starting from the current time t = 0. For the sake of explanation, the time before the current time t = 0 is also shown. The first graph in Figure 5 shows the transient target distance corresponding to the input and output values of the first filter F1d. For the sake of explanation, the target distance d* is added to the input and output values of the first filter F1d. The second graph in Figure 5 shows the transient target speed obtained by subtracting the time derivative value of the target distance in the first graph of Figure 5 from the target speed v*. At time t = 0, the target distance d* (dotted line) is decreasing stepwise from the initial distance d0 of 40 m to 20 m. The target distance (solid line) after the processing of the first filter F1d changes with a constant slope from time t = 0 and reaches the target distance d* of 20 m at the time t = 8 seconds corresponding to the first time constant τ1d. Also, the target speed (solid line) after the processing of the first filter F1d increases stepwise from 20 m / s to 22.5 m / s at time t = 0, decreases stepwise from 22.5 m / s to 20 m / s at time t = 8 seconds, and has a pulse waveform.

[0052] Similarly, Fig. 6 shows the behavior of the second filter F2d before and after processing. The first graph in Fig. 6 shows the output value (dotted line) of the first filter F1d that becomes the input value of the second filter F2d and the output value (solid line) of the second filter F2d. The second graph in Fig. 6 shows the transient target speed (dotted line) after the processing of the first filter F1d in Fig. 5 and the transient target speed (solid line) obtained by subtracting the time differential value of the target distance after the processing of the second filter F2d in the first graph of Fig. 6 from the target speed v*. The third graph in Fig. 6 shows the acceleration (solid line) obtained by differentiating the target speed in the second graph of Fig. 6 with respect to time. In Fig. 6, every 4 seconds corresponding to the second time constant τ2d, the section where the target speed increases at a constant slope (acceleration), the section where the target speed becomes a constant value, and the section where the target speed decreases at a constant slope (acceleration) are switched. Also, the target distance after the processing of the second filter F2d reaches the target distance d*, which is 20 m, at the time t = 12 seconds corresponding to the sum of the first time constant τ1d and the second time constant τ2d.

[0053] Similarly, Fig. 7 shows the behavior of the third filter F3d before and after processing. The first graph in Fig. 7 shows the output value (dotted line) of the second filter F2d that becomes the input value of the third filter F3d and the output value (solid line) of the third filter F3d. The second graph in Fig. 7 shows the transient target speed (dotted line) after the processing of the second filter F2d in Fig. 6 and the transient target speed (solid line) obtained by subtracting the time differential value of the target distance after the processing of the third filter F3d in the first graph of Fig. 7 from the target speed v*. The third graph in Fig. 7 shows the transient acceleration (dotted line) after the processing of the second filter F2d in Fig. 6 and the acceleration (solid line) obtained by differentiating the target speed after the processing of the third filter F3d in the second graph of Fig. 7 with respect to time. The fourth graph in Fig. 7 shows the jerk (solid line) obtained by differentiating the acceleration in the third graph of Fig. 7 with respect to time. In Fig. 7, every 2 seconds corresponding to the third time constant τ3d, the section where the acceleration increases at a constant slope (jerk), the section where the acceleration becomes a constant value, and the section where the acceleration decreases at a constant slope (jerk) are switched. Also, the target distance after the processing of the third filter F3d reaches the target distance d*, which is 20 m, at the time t = 14 seconds corresponding to the sum of the first time constant τ1d, the second time constant τ2d, and the third time constant τ3d.

[0054] Similarly, Fig. 8 shows the behavior of the fourth filter F4d before and after processing. The first graph in Fig. 8 shows the output value (dotted line) of the third filter F3d, which is the input value of the fourth filter F4d, and the output value (solid line) of the fourth filter F4d. The second graph in Fig. 8 shows the transient target speed (dotted line) after the processing of the third filter F3d in Fig. 7 and the transient target speed (solid line) obtained by subtracting the time derivative value of the target distance after the processing of the fourth filter F4d in the first graph of Fig. 8 from the target speed v*. The third graph in Fig. 8 shows the transient acceleration (dotted line) after the processing of the third filter F3d in Fig. 7 and the acceleration (solid line) obtained by differentiating the target speed after the processing of the fourth filter F4d in the second graph of Fig. 8 with respect to time. The fourth graph in Fig. 8 shows the transient jerk (dotted line) after the processing of the third filter F3d in Fig. 7 and the jerk (solid line) obtained by differentiating the acceleration after the processing of the fourth filter F4d in the third graph of Fig. 8 with respect to time. The fifth graph in Fig. 8 shows the jerk change rate (solid line) obtained by differentiating the jerk in the fourth graph of Fig. 8 with respect to time. In Fig. 8, every second corresponding to the fourth time constant τ4d, the intervals where the jerk increases at a constant slope (jerk change rate), the intervals where the jerk becomes a constant value, and the intervals where the jerk decreases at a constant slope (jerk change rate) are switched. Also, the target distance after the processing of the fourth filter F4d reaches the target distance d* of 20 m at the time t = 15 s corresponding to the sum of the first time constant τ1d, the second time constant τ2d, the third time constant τ3d, and the fourth time constant τ4d. That is, the sum of τ1d + τ2d + τ3d + τ4d becomes the arrival time Trch, and the arrival time Trch can be set by adjusting each time constant.

[0055] Also, the jerk and the jerk change rate can be suppressed to 0 or a finite value. Therefore, by the four-stage filter processing, it is possible to obtain a distance plan dplan(t) and a speed plan vplan(t) that can suppress sudden changes in acceleration and jerk.

[0056] It is set in the relation of τ1d≥τ2d≥τ3d≥τ4d. τ1d, τ2d, τ3d, and τ4d respectively correspond to speed, acceleration, jerk, and jerk change rate. As each time constant increases, the absolute value of each corresponding state quantity decreases.

[0057] Therefore, in order to minimize the jerk change rate while making the total value of τ1d + τ2d + τ3d + τ4d corresponding to the arrival time Trch the same value, it may be set that τ1d = τ2d = τ3d = τ4d = Trch / 4.

[0058] The motion plan generation unit 53 sets the first time constant τ1d, the second time constant τ2d, the third time constant τ3d, and the fourth time constant τ4d based on the arrival time Trch so that the total value of the first time constant τ1d, the second time constant τ2d, the third time constant τ3d, and the fourth time constant τ4d matches the target arrival time Trch. According to this configuration, the arrival time Trch can be accurately managed. At this time, the motion plan generation unit 53 may set the first time constant τ1d, the second time constant τ2d, the third time constant τ3d, and the fourth time constant τ4d to the same value (arrival time Trch / 4).

[0059] Alternatively, the motion plan generation unit 53 may set the total value of the first time constant τ1d, the second time constant τ2d, the third time constant τ3d, and the fourth time constant τ4d as the arrival time Trch.

[0060] Note that even if the set values of the time constants of each filter are interchanged with each other, that is, even if the time constants of each filter are in an arbitrary magnitude relationship, the frequency characteristics of the transfer function Fd(s) of the four-stage filter process in Equation (5) do not change, so the output values of the four-stage filter process will be equivalent values. That is, the time constants of each filter may be in an arbitrary magnitude relationship.

[0061] 1-1-4. Vehicle control unit 54 The vehicle control unit 54 calculates the acceleration command value aref of the host vehicle based on at least the speed plan vplan(t), and controls the host vehicle based on the acceleration command value aref.

[0062] For example, as shown in Equation (8), after generating the distance plan dplan(t) and the speed plan vplan(t), the vehicle control unit 54 calculates the acceleration command value aref(tr) at the current real time tr based on the deviation between the distance plan dplan(tr) corresponding to the real time tr, which is the elapsed time until now, and the actual distance dr, and the deviation between the speed plan vplan(tr) corresponding to the real time tr and the actual speed vr. Here, Kdp is the proportional gain, and Kdd is the derivative gain.

Number

[0063] Alternatively, as shown in Equation (9), after generating the distance plan dplan(t) and the speed plan vplan(t), the vehicle control unit 54 may generate the acceleration command value aref(tr) at the current real time tr based on the deviation between the speed plan vplan(tr) corresponding to the real time tr, which is the elapsed time until now, and the actual speed vr. Here, Ksp is the proportional gain, and Ksi is the integral gain.

Number

[0064] Alternatively, the plan generation unit 53 may be configured to calculate the acceleration plan aplan(t), which is the transient target acceleration at each future time t, based on the speed plan vplan(t). The plan generation unit 53 may calculate the acceleration plan aplan(t) using Equation (10), which is the time derivative of the calculation formula of the speed plan vplan(t) in Equation (7), or may calculate the acceleration plan aplan(t) by differentiating the speed plan vplan(t) with respect to time.

Number

[0065] In this case, as shown in Equation (11), the vehicle control unit 54 may calculate the acceleration command value aref(tr) at the current real time tr by further adding the acceleration plan aplan(tr) corresponding to the real time tr to the right side of Equation (8). [Number]

[0066] Alternatively, as shown in Equation (12), the vehicle control unit 54 may calculate the acceleration command value aref(tr) at the current real time tr by adding the acceleration plan aplan(tr) corresponding to the real time tr to the right side of Equation (9). [Number]

[0067] By using the acceleration plan aplan, the acceleration command value aref can be changed in a feedforward manner, and the followability can be improved.

[0068] Based on the acceleration command value aref(tr) at the current real time tr, the vehicle control unit 54 calculates command values for the output of the power unit 8 and the braking force of the electric brake device 9, and transmits each command value to the power control device and the brake control device.

[0069] The power control device controls the output of the power unit 8 such as the internal combustion engine and the motor according to the command value of the output. The brake control device controls the braking operation of the electric brake device 9 according to the command value of the braking force.

[0070] 1-1-5. Flowchart Next, using the flowchart shown in FIG. 9, a schematic processing procedure (vehicle driving support method) of the vehicle driving support device 50 according to the present embodiment will be described. The processing of the flowchart in FIG. 9 is executed, for example, every predetermined calculation cycle. Note that the processing of steps that are unnecessary at the execution time is skipped as appropriate.

[0071] In step S11, as described above, the information acquisition unit 51 determines whether there is an object to be controlled for distance around the host vehicle. If there is, the process proceeds to step S12. If not, the process ends.

[0072] In step S12, as described above, the information acquisition unit 51 acquires information on the host vehicle and information on objects existing around the host vehicle.

[0073] In step S13, as described above, the target determination unit 52 sets a target speed v* of the host vehicle and a target distance d*, which is a target value of the distance between the host vehicle and the target vehicle, based on the information of the host vehicle and the information of the target vehicle.

[0074] The processes of setting the target speed v* and the target distance d* are executed, for example, when a new object is set, when the state of the object changes, or when a specific condition is satisfied.

[0075] In step S14, as described above, the plan generation unit 53 calculates a distance plan dplan(t), which is a transient target distance at each future time t until the arrival time Trch when the distance d reaches the target distance d* and the speed v of the host vehicle reaches the target speed v*, based on the target distance d*. At the same time, based on the distance plan dplan(t) and the target speed v*, the plan generation unit 53 calculates a speed plan vplan(t), which is a transient target speed at each future time t. At this time, the plan generation unit 53 performs a four-stage filter process Fd consisting of a first filter F1d, a second filter F2d, a third filter F3d, and a fourth filter F4d on the target distance d* in virtual time representing each future time t from the present to the arrival time Trch to calculate the distance plan dplan(t).

[0076] The processes of the distance plan dplan(t) and the speed plan vplan(t) are executed, for example, when a new object is set, when the state of the object changes, or when a specific condition is satisfied.

[0077] In step S15, as described above, the vehicle control unit 54 calculates an acceleration command value aref of the host vehicle based on at least the speed plan vplan(t), and controls the host vehicle based on the acceleration command value aref.

[0078] 2. Embodiment 2 Next, the vehicle driving support device 50 according to Embodiment 2 will be described. The description of the components similar to those in the above Embodiment 1 will be omitted. The basic configuration of the vehicle driving support device 50 according to the present embodiment is the same as that in Embodiment 1, but is different from Embodiment 1 in that the planning and design unit 55 is further provided.

[0079] FIG. 10 shows a schematic block diagram of the vehicle driving support device 50 according to the present embodiment. The vehicle driving support device 50 further includes a planning and design unit 55.

[0080] The planning and design unit 55 sets the first time constant τ1d, the second time constant τ2d, the third time constant τ3d, and the fourth time constant τ4d based on the distance information regarding the distance between the host vehicle and the object, the target speed v*, and the target distance d*. The plan generation unit 53 performs a four-stage filter process using each time constant set by the planning and design unit 55.

[0081] In the present embodiment, the planning and design unit 55 sets the first time constant τ1d, the second time constant τ2d, the third time constant τ3d, and the fourth time constant τ4d such that the travel distance Xrch of the host vehicle from the present time to the arrival time Trch, which is obtained by time-integrating the speed plan vplan(t), matches the target travel distance Xtrv.

[0082] According to this configuration, while reducing the jerk and the jerk change rate generated in the host vehicle, the travel distance Xrch until the arrival time Trch can be made to match the target travel distance Xtrv, and an increase in the travel distance can be prevented.

[0083] For example, as shown in FIG. 11, when the host vehicle is traveling on the merging lane and the object is another vehicle traveling on the main line where the merging lane merges, the planning and design unit 55 sets the target travel distance Xtrv to a distance equal to or less than the distance Xend from the host vehicle to the end of the merging lane.

[0084] According to this configuration, while reducing the jerk and jerk change rate generated in the host vehicle, before the host vehicle reaches the end of the merging lane, the distance between the host vehicle and the main lane vehicle can reach the target distance d*, the speed of the host vehicle can reach the target speed v*, and the host vehicle can be safely merged into the main lane.

[0085] <Explanation of the method for setting the time constant> Figures 12 and 13 show the behavior of each value after the four-stage filter processing for explaining the method for setting the time constant according to the present embodiment. At the current time t = 0, the target distance d* is increased stepwise from 10 m to 20 m. The speed v of the host vehicle at the current time t = 0 is 20 m / s, and the target speed v* is 25 m / s, and the two are different. Therefore, as described in Embodiment 1, the initial internal calculation values of each filter of the four-stage filter processing at the current time t = 0 are set so that the speed plan vplan(0) at the current time t = 0 matches the current speed v of the host vehicle, and the distance plan dplan(0) at the current time t = 0 matches the initial distance d0. In FIG. 12, τ1d = τ2d = 5 seconds, τ3d = 2 seconds, and τ4d = 1 second are set. In FIG. 13, τ1d = τ2d = τ3d = τ4d = 13 / 4 seconds are set.

[0086] The horizontal axis is the virtual time starting from the current time t = 0. The first graph in FIGS. 12 and 13 shows the distance plan dplan(t), the second graph shows the speed plan vplan(t), the third graph shows the acceleration obtained by differentiating the second speed plan vplan(t) with respect to time, the fourth graph shows the jerk obtained by differentiating the third acceleration with respect to time, and the fifth graph shows the jerk change rate obtained by differentiating the fourth jerk with respect to time.

[0087] At the time t = 13 seconds (the arrival time Trch) corresponding to the total value of the first time constant τ1d, the second time constant τ2d, the third time constant τ3d, and the fourth time constant τ4d, the distance plan dplan reaches the target distance d* of 20 m, and the speed plan vplan reaches the target speed v* of 25 m / s.

[0088] The travel distance Xrch of the host vehicle until the arrival time Trch is given by Equation (13) and corresponds to the area of the hatched portion in FIGS. 12 and 13.

Number

[0089] When the target speed v* is constant, the change in distance until the arrival time Trch, that is, the change in distance from the initial distance d0 to the target distance d* (d* - d0), is expressed as in Equation (14).

Number

[0090] When the speed vtgt of the target vehicle that reaches the target speed v* is constant, the travel distance of the target vehicle until the arrival time Trch is expressed as in Equation (15).

Number

[0091] When Equation (13) to Equation (15) are arranged and the travel distance Xrch of the host vehicle is replaced with the target travel distance Xtrv, the following relationship of Equation (16) holds for the first time constant τ1d, the second time constant τ2d, the third time constant τ3d, the fourth time constant τ4d, the target travel distance Xtrv, the initial distance d0, the target distance d*, and the target speed v*.

Number

[0092] Therefore, the planning and design section 55 uses Equation (16) to set the total value of the first time constant τ1d, the second time constant τ2d, the third time constant τ3d, and the fourth time constant τ4d based on the initial distance d0, the target speed v*, the target distance d*, and the target travel distance Xtrv corresponding to the actual distance at the current time, and distributes the total value at a preset distribution ratio to set the first time constant τ1d, the second time constant τ2d, the third time constant τ3d, and the fourth time constant τ4d.

[0093] For example, as shown in FIG. 12, when τ1d = τ2d is set, the section from time t = 6 seconds to t = 8 seconds in FIG. 8 disappears. As a result, in FIG. 12, it is possible to reduce the fluctuation of jerk and the fluctuation of jerk change rate in the section from time t = 4 seconds to time t = 10 seconds in FIG. 8.

[0094] For example, when setting τ1d = τ2d, the planning and design department 55 uses equations (17) to (19) to distribute the total value and set the first time constant τ1d, the second time constant τ2d, the third time constant τ3d, and the fourth time constant τ4d. Here, Kr3d is a preset distribution ratio of the third time constant τ3d with respect to the total value, and Kr4d is a preset distribution ratio of the fourth time constant τ4d with respect to the total value. The distribution ratio of the time constant of each filter is set so as to satisfy the relationship of τ1d = τ2d ≥ τ3d ≥ τ4d. For example, it is set so as to satisfy 0 ≤ Kr3d ≤ 1 / 4 and 0 ≤ Kr4d ≤ 1 / 4.

Number

Number

Number

[0095] By appropriately setting the third time constant τ3d and the fourth time constant τ4d, it becomes possible to perform control considering the riding comfort. In the example of FIG. 12, the total value = 13 seconds, Kr3d = 2 / 13, and Kr4d = 1 / 13 are set.

[0096] Note that the distribution ratio of the time constant of each filter may be set to any value. The total value of the distribution ratio of the time constant of each filter is 1. Also, as described above, since the result of the four-stage filter processing does not change, the set values of the time constants of each filter may be mutually interchanged.

[0097] Alternatively, as shown in FIG. 13, when setting τ1d = τ2d = τ3d = τ4d, the distribution ratio of each time constant is set to 1 / 4.

[0098] The acceleration fluctuation in FIG. 12 is smaller than the acceleration fluctuation in FIG. 13. Also, the fluctuations of the jerk and the jerk change rate in FIG. 13 are smaller than the fluctuations of the jerk and the jerk change rate in FIG. 12. Thus, as the distribution ratio Kr3d of the third time constant τ3d increases, the fluctuation of the jerk can be reduced. As the distribution ratio Kr4d of the fourth time constant τ4d increases, the fluctuation of the jerk change rate can be reduced.

[0099] When the set values of the time constants of the respective filters are mutually interchanged, as the smallest time constant increases, the fluctuation of the jerk change rate can be reduced, and as the second smallest time constant increases, the fluctuation of the jerk can be reduced. When all the time constants are set to the same value, this corresponds to the smallest time constant becoming maximally large, and the fluctuation of the jerk change rate can be minimized. Therefore, by adjusting the set values of the time constants of the respective filters, the fluctuations of the jerk and the jerk change rate can be adjusted, and the riding comfort can be optimized.

[0100] <Flowchart> Next, using the flowchart shown in FIG. 14, a schematic processing procedure (vehicle driving support method) of the vehicle driving support device 50 according to the present embodiment will be described. The processing of the flowchart in FIG. 14 is executed, for example, every predetermined calculation cycle. Note that the processing of steps that are unnecessary at the execution time is skipped as appropriate.

[0101] Steps S11 to S15 in FIG. 14 are the same as steps S11 to S15 in FIG. 9 of Embodiment 1, and thus the description thereof is omitted. Step S21 is added between step S13 and step S14.

[0102] In step S21, as described above, based on the distance information regarding the distance between the host vehicle and the object, the target speed v*, and the target distance d*, the planning and design unit 55 sets the first time constant τ1d, the second time constant τ2d, the third time constant τ3d, and the fourth time constant τ4d. In the present embodiment, as described above, the planning and design unit 55 sets the first time constant τ1d, the second time constant τ2d, the third time constant τ3d, and the fourth time constant τ4d such that the travel distance Xrch of the host vehicle from the present time to the arrival time Trch, which is obtained by time-integrating the speed plan vplan(t), matches the target travel distance Xtrv.

[0103] In step S14, the plan generation unit 53 performs a four-stage filter process using each time constant set by the planning and design unit 55.

[0104] 3. Embodiment 3 Next, the vehicle driving support device 50 according to Embodiment 3 will be described. The description of the components having the same configuration as in the above-described Embodiment 1 will be omitted. The basic configuration of the vehicle driving support device 50 according to the present embodiment is the same as that of Embodiment 1, but is different from Embodiment 1 in that the planning and design unit 55 is further provided as in Embodiment 2.

[0105] Fig. 15 shows a schematic block diagram of the vehicle driving support device 50 according to the present embodiment. Similar to Embodiment 2, the vehicle driving support device 50 further includes a planning and design unit 55.

[0106] In the present embodiment, based on the speed information regarding the speed of the host vehicle, the distance information regarding the distance between the host vehicle and the object, the target speed v*, and the target distance d*, the planning and design unit 55 sets the first time constant τ1d, the second time constant τ2d, the third time constant τ3d, and the fourth time constant τ4d. The plan generation unit 53 performs a four-stage filter process using each time constant set by the planning and design unit 55.

[0107] <Derivation of the method for setting the time constant> FIG. 16 shows the behavior of each value after the four-stage filter process for explaining the time constant setting method according to the present embodiment. The example of FIG. 16 is a case where, for example, the host vehicle follows a preceding vehicle that is slower than the host vehicle. At the current time t = 0, the target distance d* is stepwise decreased from 40 m to 20 m. The speed v of the host vehicle at the current time t = 0 is 20 m / s, and the target speed v* set to the speed vtgt of the target vehicle is 15 m / s, and the two are different. Therefore, as described in Embodiment 1, the initial internal operation values of the respective filters of the four-stage filter process at the current time t = 0 are set so that the speed plan vplan(0) at the current time t = 0 coincides with the current speed v of the host vehicle, and the distance plan dplan(0) at the current time t = 0 coincides with the initial distance d0. In FIG. 16, τ1d = τ2d = 5 seconds, τ3d = 2 seconds, and τ4d = 1 second are set.

[0108] The horizontal axis is the virtual time starting from the current time t = 0. The first graph in FIG. 16 shows the distance plan dplan(t), the second graph shows the speed plan vplan(t), the third graph shows the acceleration obtained by differentiating the second speed plan vplan(t) with respect to time, the fourth graph shows the jerk obtained by differentiating the third acceleration with respect to time, and the fifth graph shows the jerk change rate obtained by differentiating the fourth jerk with respect to time.

[0109] In FIG. 16, from the time t = 0 seconds to the time t = 1 second, the absolute value of the jerk gradually increases, from the time t = 1 second to the time t = 2 seconds, the absolute value of the jerk becomes a constant value, and from the time t = 2 seconds to the time t = 3 seconds, the absolute value of the jerk gradually decreases. From the time t5 to the time t8, similarly, after the absolute value of the jerk increases, it becomes a constant value and then decreases.

[0110] The jerk change rate dj(t) in FIG. 16 is expressed as in Equation (20). Here, dJ is the target maximum jerk change rate and is a positive value (absolute value). Also, τ1d = τ2d.

Equation

[0111] By successively integrating the jerk change rate dj(t) with respect to time, the jerk j(t), acceleration a(t), velocity v(t), and distance d(t) can be obtained as shown in Expressions (21) to (24). [Number] [Number] [Number] [Number]

[0112] Substituting Expression (20) into and performing calculations on Expressions (21) to (24) yields Expressions (25) to (28). Here, C10 to C83 are constants. [Number] [Number] [Number] [Number]

[0113] At the current time t = 0, the velocity v(0) of the host vehicle is the initial velocity v0, and the distance d(0) is the initial distance d0. Also, at each time t, the jerk j, acceleration a, velocity v, and distance d are continuous. Although details are omitted, from these facts, by solving Expressions (25) to (28) in time order, the above constants C10 to C83 can be derived.

[0114] Each of the derived constants C10 to C83 is expressed by an equation including the initial velocity v0, the initial distance d0, the target velocity v*, the target distance d*, the first time constant τ1d, the second time constant τ2d, the third time constant τ3d, and the fourth time constant τ4d. The relational expression necessary to achieve the target, obtained by organizing them, becomes Equation (29).

Number

[0115] <Method for setting each time constant> The planning and design department 55 uses Equation (29) to set the total value of the first time constant τ1d or the second time constant τ2d, the third time constant τ3d, and the fourth time constant τ4d based on the initial velocity v0 corresponding to the actual velocity of the host vehicle at the current time, the initial distance d0 corresponding to the actual distance at the current time, the target velocity v*, and the target distance d*, and distributes the total value according to a preset distribution ratio to set the first time constant τ1d, the second time constant τ2d, the third time constant τ3d, and the fourth time constant τ4d. Note that τ1d = τ2d is set. For example, the distribution ratio of the time constants of each filter is set so as to satisfy the relationship of τ1d = τ2d ≥ τ3d ≥ τ4d.

[0116] When the set values of the time constants of each filter are interchanged with each other, instead of τ1d = τ2d, the time constants of any two filters may be set to the same value. Also, the distribution ratio of the time constants of each filter may be set to any value.

[0117] For example, in Equation (25), since C10 = 0, t = τ4d and C20 = -dJ × τ4d. C20 is the value of the jerk j at τ4d ≦ t ≦ τ3d in Equation (25) and is the maximum value of the absolute value of the jerk j. τ4d is the time t when the maximum value of the absolute value of the jerk j is reached. By replacing C20 with the target maximum jerk j* and rearranging, the equation τ4d = j* / dJ is obtained, and τ4d may be set to the value obtained by dividing the target maximum jerk j* by the target maximum jerk change rate dJ. Note that the target maximum jerk j* is a positive value (absolute value) and may be set in advance. The target maximum jerk change rate dJ is a positive value (absolute value) and may be set in advance. Therefore, by setting τ4d as described above, the absolute value of the jerk can be limited to the upper limit. Here, τ4d is the smallest time constant, and when the set values of the time constants of each filter are mutually interchanged, τ4d is replaced with the smallest time constant.

[0118] Therefore, the planning and design department 55 sets the smallest time constant among the first time constant τ1d, the second time constant τ2d, the third time constant τ3d, and the fourth time constant τ4d (in this example, the fourth time constant τ4d) so that the maximum value of the absolute value of the jerk change rate dj at each future time t obtained by three-time differentiating the speed plan vplan(t) matches the target maximum jerk change rate dJ, and the maximum value of the absolute value of the jerk j at each future time t obtained by two-time differentiating the speed plan vplan(t) matches the target maximum jerk j*.

[0119] Specifically, the planning and design department 55 sets the smallest time constant (in this example, τ4d) to the value obtained by dividing the target maximum jerk j* by the target maximum jerk change rate dJ (τ4d = j* / dJ). The other time constants (in this example, τ1d, τ2d, τ3d) may be set so that Equation (29) is satisfied.

[0120] Also, when solving each constant in Formula (25) and Formula (26) in chronological order, in Formula (26), when t = τ3d + τ4d and C40 = 0, C41 = -dJ × τ3d × τ4d. C41 is the value of the acceleration a when τ3d + τ4d ≤ t ≤ τ1d in Formula (26), and it is the maximum value of the absolute value of the acceleration a. τ3d + τ4d is the time t when the maximum value of the absolute value of the acceleration a is reached. By replacing C41 with the target maximum acceleration a* and arranging, an equation of τ3d × τ4d = a* / dJ can be obtained, and τ3d × τ4d may be set to a value obtained by dividing the target maximum acceleration a* by the target maximum jerk change rate dJ. Note that the target maximum acceleration a* is a positive value (absolute value) and may be set in advance. Therefore, by setting τ3d and τ4d as described above, the absolute value of the acceleration can be limited to the upper limit. Here, τ3d is the second smallest time constant. When the set values of the time constants of each filter are mutually interchanged, τ3d is replaced with the second smallest time constant.

[0121] Therefore, the planning and design department 55 makes the maximum value of the absolute value of the jerk change rate dj at each future time t obtained by three-time differentiating the velocity plan vplan(t) coincide with the target maximum jerk change rate dJ, and makes the maximum value of the absolute value of the acceleration a at each future time t obtained by one-time differentiating the velocity plan vplan(t) coincide with the target maximum acceleration a*. Among the first time constant τ1d, the second time constant τ2d, the third time constant τ3d, and the fourth time constant τ4d, the smallest time constant (in this example, the fourth time constant τ4d) and the second smallest time constant (in this example, the third time constant τ3d) are set.

[0122] Specifically, the planning and design department 55 sets the smallest time constant (τ4d in this example) and the second smallest time constant (τ3d in this example) such that the product of the smallest time constant and the second smallest time constant is equal to the value obtained by dividing the target maximum acceleration a* by the target maximum jerk change rate dJ (τ3d × τ4d = a* / dJ). For example, when the smallest time constant (τ4d) is set to j* / dJ (τ4d = j* / dJ) to upper limit the absolute value of the jerk j by the target maximum jerk j*, the second smallest time constant (τ3d) may be set to the value obtained by dividing the target maximum acceleration a* by the target maximum jerk j* (τ3d = a* / j*). Alternatively, while satisfying τ4d × τ3d = a* / dJ, the smallest time constant (τ4d) and the second smallest time constant (τ3d) may be set to a predetermined ratio. Also, the other time constants (τ1d, τ2d in this example) may be set so that Equation (29) is satisfied.

[0123] Details are omitted, but for each of the vehicle speed v in Equation (27) and the distance d in Equation (28), a method for setting each time constant to a target value can be considered.

[0124] If τ1d is not set to τ2d, the number of time intervals increases. However, similar to Equation (20), the absolute value of the jerk change rate dj(t) for each time interval is set to be the target maximum jerk change rate dJ or 0. Even in this case, each constant C is derived in the same manner, and a derivation result (function) similar to Equation (29) for setting each time constant is obtained based on the initial velocity v0, the initial distance d0, the target velocity v*, and the target distance d*. Therefore, as in each of the above-described configurations, the planning and design unit 55 can set the first time constant τ1d, the second time constant τ2d, the third time constant τ3d, and the fourth time constant τ4d based on the initial distance d0, the target velocity v*, the target distance d*. Also, even when the target velocity v*, the initial velocity v0, the target distance d*, and the initial distance d0 are different from the example in FIG. 16, if the absolute value of the jerk change rate dj(t) for each time interval is set to be the target maximum jerk change rate dJ or 0, a similar derivation result (function) can be obtained, and thus each time constant can be set as in each of the above-described configurations.

[0125] <Flowchart> Next, using the flowchart shown in FIG. 17, a schematic processing procedure (vehicle driving support method) of the vehicle driving support device 50 according to the present embodiment will be described. The processing of the flowchart in FIG. 17 is executed, for example, at every predetermined calculation cycle. Note that the processing of steps that are unnecessary at the execution time is skipped as appropriate.

[0126] Steps S11 to S15 in FIG. 17 are the same as steps S11 to S15 in FIG. 9 of the first embodiment, and thus the description thereof is omitted. Step S31 is added between step S13 and step S14.

[0127] In step S31, as described above, the planning and design unit 55 sets the first time constant τ1d of the first filter, the second time constant τ2d of the second filter, the third time constant τ3d of the third filter, and the fourth time constant τ4d of the fourth filter based on the speed information regarding the speed of the host vehicle, the distance information regarding the distance between the host vehicle and the object, the target speed v*, and the target distance d*.

[0128] In step S14, the plan generation unit 53 performs four-stage filter processing using each time constant set by the plan design unit 55.

[0129] 4. Embodiment 4 Next, the vehicle driving support device 50 according to Embodiment 4 will be described. Description of the same components as those in the above Embodiment 1, 2, or 3 will be omitted. The basic configuration of the vehicle driving support device 50 according to this embodiment is the same as that in Embodiment 1, 2, or 3, but the processing of the vehicle control unit 54 is different from that in Embodiment 1, 2, or 3.

[0130] In this embodiment, the vehicle control unit 54 calculates a predicted value de of the distance and a predicted value ve of the speed of the host vehicle at each future time t using a dynamic vehicle model representing the behavior of the host vehicle, and based on an evaluation value for the distance deviation, which is the deviation between the distance plan dplan and the predicted value de of the distance, and an evaluation value for the speed deviation, which is the deviation between the speed plan vplan and the predicted value ve of the speed, calculates an acceleration command value aref at each future time, and controls the host vehicle based on the acceleration command value aref.

[0131] The dynamic vehicle model is a model for predicting the behavior of the host vehicle from the current time t = 0 to a future point up to the prediction period Th at regular intervals of Tper. Various known vehicle models such as a two-wheeled model are used. The vehicle control unit 54 solves an optimization problem of obtaining a control input u that minimizes an evaluation function J for evaluating each of the distance deviation and the speed deviation at regular intervals of Tper, and calculates the solution as the acceleration command value aref.

[0132] At this time, the number of prediction time points for the predicted value dek of the distance and the predicted value vek of the speed is N. The number of time points N is obtained by N = Th / Tper. The period from the current time t = 0 to a future point up to the prediction period Th is called the "horizon".

[0133] The calculation process of the acceleration command value aref by the vehicle control unit 54 will be described in more detail below. Equation (30) represents that the control input u that minimizes the evaluation function J is obtained. Here, x is the vehicle state quantity, and x0 is the initial value of the vehicle state quantity x. Also, x' is the predicted value of the vehicle state quantity x. f(x, u) is a vector-valued function related to the dynamic vehicle model.

Number

[0134] The vehicle state quantity x and the control input u are set as in Equation (31). Here, [···] T represents the transposed matrix.

Number

[0135] The dynamic vehicle model can be expressed as in Equation (32). Here, Ta is the response delay of the drive control device with respect to the acceleration command value aref.

Number

[0136] The evaluation function J is expressed as in Equation (33). Here, xk is the predicted value of the vehicle state quantity at the prediction time point k (k = 0, ···, N - 1), and uk is the control input at the prediction time point k (k = 0, ···, N - 1). h is a vector-valued function related to the evaluation item, and hN is a vector-valued function related to the evaluation item at the prediction time point N. rk is the target value at the prediction time point k (k = 0, ···, N - 1). W and WN are weight matrices, which are diagonal matrices having the weights for their respective evaluation items in the diagonal components.

Number

[0137] The vehicle control unit 54 sets the vector value functions h and hN regarding the evaluation items as shown in Equation (34). Here, dek is the predicted value of the distance at the prediction time point k (k = 0, ···, N). vek is the predicted value of the speed of the host vehicle at the prediction time point k (k = 0, ···, N). arefk is the acceleration command value at the prediction time point k (k = 0, ···, N).

Number

[0138] The vehicle control unit 54 sets the target values rk and rN shown in Equation (35) so that the predicted value dek of the distance, the predicted value vek of the speed, and the acceleration command value aref,k each become small. Here, dplan,k is the value corresponding to the prediction time point k in the distance plan dplan(t) of Equation (6), and dplan,N is the value corresponding to the prediction time point N in the distance plan dplan(t) of Equation (6).

Number

[0139] The vehicle control unit 54 evaluates the deviation between the vector value function h and the target value rk, and the deviation between the vector value function hN and the target value rN using the evaluation function J. The vehicle control unit 54 solves an optimization problem to obtain a control input u that minimizes the evaluation value of each deviation at regular intervals, and sets the acceleration command value aref(k) at each prediction time point k of the obtained solution as the acceleration command value aref(t) at each future time t. Since the process of solving the optimization problem itself is a known technique, detailed description is omitted. Similar to Embodiment 1, the vehicle control unit 54 controls the host vehicle based on the acceleration command value aref(t) at each time t.

[0140] In the above configuration, the vehicle control unit 54 obtains the control input u that minimizes the evaluation value of each deviation. However, the vehicle control unit 54 may obtain the control input u such that the evaluation value of each deviation is smaller than a preset threshold value. Further, if the vehicle control unit 54 cannot obtain the control input u such that the evaluation value of each deviation is smaller than the threshold value even after performing iterative calculations a predetermined number of times, the vehicle control unit 54 may obtain the control input u when the evaluation value becomes the minimum among the plurality of evaluation values obtained by the iterative calculations.

[0141] Also, the vehicle control unit 54 obtains the control input u that minimizes the evaluation value of each deviation. However, by inverting the sign of the evaluation function J, the vehicle control unit 54 may obtain the control input u that maximizes the evaluation value of each deviation. Further, the vehicle control unit 54 may obtain the control input u such that the evaluation value of each deviation is larger than a preset threshold value. Further, if the vehicle control unit 54 cannot obtain the control input u such that the evaluation value of each deviation is larger than the threshold value even after performing iterative calculations a predetermined number of times, the vehicle control unit 54 may obtain the control input u when the evaluation value becomes the maximum among the plurality of evaluation values obtained by the iterative calculations.

[0142] In the present embodiment, by evaluating the deviation of the distance plan and the deviation of the speed plan, it is possible to calculate an acceleration command value for smoothly following the distance plan and the speed plan within the horizon. Further, by incorporating the response delay of the drive control device into the dynamic vehicle model, it is possible to calculate a control amount that takes into account the delay of the vehicle with respect to the acceleration command value.

[0143] Further, the plan generation unit 53 may further calculate the acceleration plan aplan(t) using Equation (10) and output it to the vehicle control unit 54. Then, the vehicle control unit 54 may set the target value rk as in Equation (36) and calculate the acceleration command value aref by optimization calculation. aplan,k is a value corresponding to the prediction time point k in the acceleration plan aplan(t) of Equation (10).

Equation

[0144] 5. Embodiment 5 Next, the vehicle driving support device 50 according to Embodiment 5 will be described. The description of the components similar to those in the above-described Embodiments 1, 2, 3, or 4 will be omitted. The basic configuration of the vehicle driving support device 50 according to the present embodiment is the same as that in Embodiments 1, 2, 3, or 4, but the point that the target object is set at the stop position is different from that in Embodiments 1, 2, 3, or 4.

[0145] In the present embodiment, the information acquisition unit 51 sets the target object at the stop position existing in front of the host vehicle. For example, the stop position is set at various stop lines (for example, a stop line for a temporary stop, a stop line for a crosswalk, a stop line for an intersection), a stop line of a traffic signal, a position on the front side of a stopped vehicle or an obstacle ahead, and a stop position due to various factors. The case where the stop position is a stop line of an intersection is shown in FIG. 18.

[0146] In addition, the information acquisition unit 51 acquires information on the traffic signal in front of the host vehicle, and when it is a red signal, for example, sets the stop line of the traffic signal or the position on the front side of the vehicle stopped by the red signal as the stop position. When the information acquisition unit 51 detects another vehicle or a pedestrian crossing the intersection or the road in front of the host vehicle, it sets the position on the front side of them as the stop position.

[0147] The target determination unit 52 sets the target speed v* of the host vehicle and the target distance d*, which is the target value of the distance between the host vehicle and the target vehicle, based on the information of the host vehicle and the information of the target object (in this example, the stop position).

[0148] In the present embodiment, the target determination unit 52 sets the target speed v* of the host vehicle to 0, which is the speed of the stop position (v* = 0). Further, the target determination unit 52 sets the target distance d* to the distance from the position of the host vehicle to the stop position.

[0149] The configurations of the plan generation unit 53, the vehicle control unit 54, and the plan design unit 55 are the same as those in Embodiments 1, 2, 3, or 4, and thus the description thereof will be omitted.

[0150] <Other Embodiments> (1) In each of the above embodiments, the case where each of the first filter F1d, the second filter F2d, the third filter F3d, and the fourth filter F4d is a moving average filter has been described as an example. However, each of the first filter F1d, the second filter F2d, the third filter F3d, and the fourth filter F4d may be a low-pass filter such as a first-order lag filter.

[0151] <Summary of Aspects of the Present Disclosure> Hereinafter, aspects of the present disclosure will be summarized and described as appendices. (Appendix 1) An information acquisition unit that acquires information on the host vehicle and information on an object existing around the host vehicle; A target determination unit that sets a target speed of the host vehicle and a target distance that is a target value of the distance between the host vehicle and the object based on the information on the host vehicle and the information on the object; A plan generation unit that calculates a distance plan that is a transient target distance at each future time until an arrival time when the distance reaches the target distance and the speed of the host vehicle reaches the target speed based on the target distance, and calculates a speed plan that is a transient target speed at each future time based on the distance plan and the target speed; A vehicle control unit that calculates an acceleration command value of the host vehicle based on at least the speed plan and controls the host vehicle based on the acceleration command value, and The plan generation unit is a vehicle driving support device that calculates the distance plan by performing four-stage filter processing including a first filter, a second filter, a third filter, and a fourth filter on the target distance at virtual time representing each future time from now until the arrival time.

[0152] (Appendix 2) The vehicle driving support device according to Appendix 1, wherein the object is another vehicle traveling in front of or behind the driving lane in which the host vehicle is traveling.

[0153] (Appendix 3) The vehicle driving support device according to Supplementary Note 1, wherein the object is another vehicle traveling in the lane to which the host vehicle is moving.

[0154] (Supplementary Note 4) The vehicle driving support device according to Supplementary Note 1, wherein the object is a stop position existing in front of the host vehicle.

[0155] (Supplementary Note 5) Each of the first filter, the second filter, the third filter, and the fourth filter is a moving average filter, and each of a first time constant that is a time constant of the first filter, a second time constant that is a time constant of the second filter, a third time constant that is a time constant of the third filter, and a fourth time constant that is a time constant of the fourth filter is a moving average time of the moving average filter. The vehicle driving support device according to any one of Supplementary Notes 1 to 4.

[0156] (Supplementary Note 6) The vehicle driving support device according to any one of Supplementary Notes 1 to 5, wherein the plan generation unit sets the first time constant, the second time constant, the third time constant, and the fourth time constant based on the arrival time so that the sum of the first time constant that is the time constant of the first filter, the second time constant that is the time constant of the second filter, the third time constant that is the time constant of the third filter, and the fourth time constant that is the time constant of the fourth filter matches the target arrival time.

[0157] (Supplementary Note 7) The vehicle driving support device according to any one of Supplementary Notes 1 to 5, wherein the plan generation unit sets the sum of the first time constant that is the time constant of the first filter, the second time constant that is the time constant of the second filter, the third time constant that is the time constant of the third filter, and the fourth time constant that is the time constant of the fourth filter as the arrival time.

[0158] (Supplementary Note 8) The vehicle driving support device according to any one of Appendices 1 to 7, wherein the plan generation unit sets the first time constant, which is the time constant of the first filter, the second time constant, which is the time constant of the second filter, the third time constant, which is the time constant of the third filter, and the fourth time constant, which is the time constant of the fourth filter, to the same value.

[0159] (Appendix 9) The vehicle driving support device according to any one of Appendices 1 to 5, further comprising a plan design unit that sets the first time constant, which is the time constant of the first filter, the second time constant, which is the time constant of the second filter, the third time constant, which is the time constant of the third filter, and the fourth time constant, which is the time constant of the fourth filter, based on the speed information regarding the speed of the host vehicle, the distance information regarding the distance, the target speed, and the target distance.

[0160] (Appendix 10) The vehicle driving support device according to Appendix 9, wherein the plan design unit sets the first time constant, the second time constant, the third time constant, and the fourth time constant so that the maximum value of the absolute value of the jerk change rate at each future time obtained by three-time differentiating the speed plan matches the target maximum jerk change rate, and sets the smallest one of the first time constant, the second time constant, the third time constant, and the fourth time constant so that the maximum value of the absolute value of the jerk at each future time obtained by two-time differentiating the speed plan matches the target maximum jerk.

[0161] (Appendix 11) The vehicle driving support device according to Appendix 10, wherein the plan design unit sets the smallest time constant to a value obtained by dividing the target maximum jerk by the target maximum jerk change rate.

[0162] (Appendix 12) The planning and design department sets the smallest time constant and the second smallest time constant among the first time constant, the second time constant, the third time constant, and the fourth time constant such that the maximum value of the absolute value of the jerk change rate at each future time obtained by three-time differentiating the speed plan with respect to time matches the target maximum jerk change rate, and the maximum value of the absolute value of the acceleration at each future time obtained by first-time differentiating the speed plan with respect to time matches the target maximum acceleration. The vehicle driving support device according to any one of Appendices 9 to 11.

[0163] (Appendix 13) The planning and design department sets the smallest time constant and the second smallest time constant such that the product value of the smallest time constant and the second smallest time constant becomes the value obtained by dividing the target maximum acceleration by the target maximum jerk change rate. The vehicle driving support device according to Appendix 12.

[0164] (Appendix 14) The vehicle driving support device according to any one of Appendices 1 to 5, further comprising a planning and design department that sets a first time constant that is the time constant of the first filter, a second time constant that is the time constant of the second filter, a third time constant that is the time constant of the third filter, and a fourth time constant that is the time constant of the fourth filter based on the distance information regarding the distance, the target speed, and the target distance.

[0165] (Appendix 15) The planning and design department sets the first time constant, the second time constant, the third time constant, and the fourth time constant such that the driving distance of the host vehicle from the present time to the arrival time obtained by integrating the speed plan with respect to time matches the target driving distance. The vehicle driving support device according to Appendix 14.

[0166] (Appendix 16) When the host vehicle is traveling on a merging lane and the object is another vehicle traveling on the main lane where the merging lane merges, the planning and design department sets the target driving distance to a distance equal to or less than the distance from the host vehicle to the end of the merging lane. The vehicle driving support device according to Appendix 15.

[0167] (Appendix 17) The vehicle control unit calculates predicted values of the distance and the speed of the host vehicle at each future time using a dynamic vehicle model representing the behavior of the host vehicle, and based on an evaluation value for a distance deviation that is a deviation between the distance plan and the predicted value of the distance, and an evaluation value for a speed deviation that is a deviation between the speed plan and the predicted value of the speed, calculates the acceleration command value at each future time. The vehicle driving support device according to any one of Appendices 1 to 16.

[0168] Although various exemplary embodiments and examples are described in the present disclosure, the various features, aspects, and functions described in one or more of the embodiments are not limited to the application of a particular embodiment, but are applicable to the embodiments alone or in various combinations. Therefore, countless variations not illustrated are envisioned within the scope of the technology disclosed in this specification. For example, it includes cases where at least one component is deformed, added, or omitted, and further cases where at least one component is extracted and combined with components of other embodiments.

Description of Reference Numerals

[0169] 50: Vehicle driving support device, 51: Information acquisition unit, 52: Target determination unit, 53: Plan generation unit, 54: Vehicle control unit, 55: Plan design unit, F1d: First filter, F2d: Second filter, F3d: Third filter, F4d: Fourth filter, Fd: Four-stage filter process, τ1d: First time constant, τ2d: Second time constant, τ3d: Third time constant, τ4d: Fourth time constant, Trch: Arrival time, Xend: Distance to the end, Xrch: Travel distance, Xtrv: Target travel distance, a*: Target maximum acceleration, aplan: Acceleration plan, aref: Acceleration command value, d*: Target distance, dJ: Target maximum jerk change rate, dj: Jerk change rate, dplan: Distance plan, j: Jerk, j*: Target maximum jerk, v: Speed of the host vehicle, v*: Target speed, vplan: Speed plan, vr: Actual speed, vtgt: Speed of the target vehicle

Claims

1. An information acquisition unit that acquires information on the host vehicle and information on an object existing around the host vehicle; A target determination unit that sets a target speed of the host vehicle and a target distance that is a target value of the distance between the host vehicle and the object based on the information on the host vehicle and the information on the object; A plan generation unit that calculates a distance plan, which is a transient target distance at each future time until a reach time when the distance reaches the target distance and the speed of the host vehicle reaches the target speed, based on the target distance, and calculates a speed plan, which is a transient target speed at each future time, based on the distance plan and the target speed; A vehicle control unit that calculates an acceleration command value of the host vehicle based on at least the speed plan and controls the host vehicle based on the acceleration command value, The plan generation unit performs four-stage filter processing including a first filter, a second filter, a third filter, and a fourth filter on the target distance at virtual time representing each future time from the present to the reach time to calculate the distance plan, and a vehicle driving support device.

2. The vehicle driving support device according to claim 1, wherein the object is another vehicle traveling in front of or behind the travel lane in which the host vehicle is traveling.

3. The vehicle driving support device according to claim 1, wherein the object is another vehicle traveling in the lane to which the host vehicle is moving.

4. The vehicle driving support device according to claim 1, wherein the object is a stop position existing in front of the host vehicle.

5. Each of the first filter, the second filter, the third filter, and the fourth filter is a moving average filter, and each of a first time constant that is a time constant of the first filter, a second time constant that is a time constant of the second filter, a third time constant that is a time constant of the third filter, and a fourth time constant that is a time constant of the fourth filter is a moving average time of the moving average filter, and the vehicle driving support device according to claim 1. Claim 6 The plan generation unit sets the first time constant which is the time constant of the first filter, the second time constant which is the time constant of the second filter, the third time constant which is the time constant of the third filter, and the fourth time constant which is the time constant of the fourth filter based on the arrival time, such that the sum of the first time constant, the second time constant, the third time constant, and the fourth time constant matches the target arrival time. The vehicle driving support device according to any one of claims 1 to 5. Claim 7 The plan generation unit sets the sum of the first time constant which is the time constant of the first filter, the second time constant which is the time constant of the second filter, the third time constant which is the time constant of the third filter, and the fourth time constant which is the time constant of the fourth filter as the arrival time. The vehicle driving support device according to any one of claims 1 to 5. Claim 8 The plan generation unit sets the first time constant which is the time constant of the first filter, the second time constant which is the time constant of the second filter, the third time constant which is the time constant of the third filter, and the fourth time constant which is the time constant of the fourth filter to the same value. The vehicle driving support device according to any one of claims 1 to 5. Claim 9 The vehicle driving support device according to any one of claims 1 to 5, further comprising a plan design unit that sets the first time constant which is the time constant of the first filter, the second time constant which is the time constant of the second filter, the third time constant which is the time constant of the third filter, and the fourth time constant which is the time constant of the fourth filter based on speed information regarding the speed of the host vehicle, distance information regarding the distance, the target speed, and the target distance. Claim 10 The planning and design department sets the smallest one among the first time constant, the second time constant, the third time constant, and the fourth time constant such that the maximum value of the absolute value of the jerk change rate at each future time obtained by three-time differentiating the speed plan with respect to time matches the target maximum jerk change rate, and the maximum value of the absolute value of the jerk at each future time obtained by two-time differentiating the speed plan with respect to time matches the target maximum jerk. The vehicle driving support device according to claim 9.

11. The planning and design department sets the smallest one of the time constants to a value obtained by dividing the target maximum jerk by the target maximum jerk change rate. The vehicle driving support device according to claim 10.

12. The planning and design department sets the smallest one and the second smallest one among the first time constant, the second time constant, the third time constant, and the fourth time constant such that the maximum value of the absolute value of the jerk change rate at each future time obtained by three-time differentiating the speed plan with respect to time matches the target maximum jerk change rate, and the maximum value of the absolute value of the acceleration at each future time obtained by one-time differentiating the speed plan with respect to time matches the target maximum acceleration. The vehicle driving support device according to claim 9.

13. The planning and design department sets the smallest one and the second smallest one of the time constants such that the product value of the smallest one and the second smallest one of the time constants becomes a value obtained by dividing the target maximum acceleration by the target maximum jerk change rate. The vehicle driving support device according to claim 12.

14. The vehicle driving support device according to any one of claims 1 to 5, further comprising a planning and design department that sets the first time constant, which is the time constant of the first filter, the second time constant, which is the time constant of the second filter, the third time constant, which is the time constant of the third filter, and the fourth time constant, which is the time constant of the fourth filter, based on the distance information regarding the distance, the target speed, and the target distance.

15. The vehicle travel support device according to claim 14, wherein the planning and design unit sets the first time constant, the second time constant, the third time constant, and the fourth time constant such that the travel distance of the host vehicle from the present time to the arrival time, which is obtained by time-integrating the speed plan, matches the target travel distance.

16. The vehicle travel support device according to claim 15, wherein the planning and design unit sets the target travel distance to a distance less than or equal to the distance from the host vehicle to the end of the merging lane when the host vehicle is traveling on the merging lane and the object is another vehicle traveling on the main lane into which the merging lane merges.

17. The vehicle control unit calculates predicted values of the distance and the speed of the host vehicle at each future time using a dynamic vehicle model representing the behavior of the host vehicle, and calculates an acceleration command value at each future time based on an evaluation value for a distance deviation, which is a deviation between the distance plan and the predicted value of the distance, and an evaluation value for a speed deviation, which is a deviation between the speed plan and the predicted value of the speed. The vehicle travel support device according to any one of claims 1 to 5.

18. An information acquisition step of acquiring information on the host vehicle and information on an object existing around the host vehicle; A target determination step of setting a target speed of the host vehicle and a target distance, which is a target value of the distance between the host vehicle and the object, based on the information on the host vehicle and the information on the object; A plan generation step of calculating a distance plan, which is a transient target distance at each future time until an arrival time when the distance reaches the target distance and the speed of the host vehicle reaches the target speed, based on the target distance, and calculating a speed plan, which is a transient target speed at each future time, based on the distance plan and the target speed; A vehicle control step of calculating an acceleration command value of the host vehicle based on at least the speed plan and controlling the host vehicle based on the acceleration command value. In the planned generation step, a vehicle driving support method for calculating the distance plan is provided, in which, at virtual times representing each future time from the present to the arrival time, four-stage filtering processing including a first filter, a second filter, a third filter, and a fourth filter is performed on the target distance.

Images