JP2005001500A - Automatic brake controller - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To smoothly control braking in an own vehicle for making braking force act on a vehicle, based on the possibility of contact of the own vehicle with a body on a front side of the own vehicle. <P>SOLUTION: When the vehicle travels under the condition where the own vehicle detects the body on the front side, the possibility of the contact with the body on the front side is calculated, based on a relative distance to the front side body and an own vehicle speed, and a contact evading braking torque for avoiding the contact with the body on the front side is generated to make the braking force act on the vehicle, in response to the possibility of the contact and a degree of overlapping between front side travel loci of the front side body and the vehicle, when the the possibility of the contact is a prescribed threshold value or less. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

[0001]
BACKGROUND OF THE INVENTION
The present invention relates to an automatic brake control device that automatically generates a braking force in accordance with the possibility of contact between the host vehicle and an object in front of the host vehicle.
[0002]
[Prior art]
As a conventional automatic brake control device, automatic braking is performed with full braking when the distance between the host vehicle and the vehicle ahead of the host vehicle is smaller than a predetermined threshold with a risk of contact. When changing the lane to overtake the vehicle, for example, it is known that the vehicle ahead is detected and the driver determines that the lane is changed when the blinker operation is performed, and the automatic braking is deactivated. (For example, refer to Patent Document 1).
[0003]
[Patent Document 1]
Japanese Patent Laid-Open No. 05-024519
[0004]
[Problems to be solved by the invention]
However, in the conventional automatic brake control device described above, the intervention of the braking control is switched by the flag based on whether or not the own vehicle changes the lane, so that there is only a case where the braking control is activated or deactivated. , There is an unresolved problem of giving the driver a sense of incongruity.
Therefore, the present invention has been made paying attention to the unsolved problems of the above-described conventional example, and provides an automatic brake control device capable of performing smooth braking control without giving a driver a sense of incongruity. The purpose is that.
[0005]
[Means for Solving the Problems]
In order to achieve the above object, an automatic brake control device according to the present invention detects an object ahead of the host vehicle by a front object detection unit, detects a vehicle speed of the host vehicle by a vehicle speed detection unit, and detects a contact possibility index calculation unit. And calculating the possibility of contact with the front object based on the relative distance from the front object detected by the front object detection means and the own vehicle speed detected by the vehicle speed detection means, and the degree of overlap detection means The degree of overlap between the front object detected by the object detection means and the forward travel locus of the host vehicle is detected, and the contact possibility calculated by the contact possibility index calculation means by the contact avoidance braking torque calculation means and the overlap degree detection means The contact avoidance braking torque is calculated on the basis of the degree of overlap detected in step S3, and the braking / driving force control means calculates the contact avoidance braking torque calculated by the contact avoidance braking torque calculation means and the braking / driving torque by the driver's operation. Controlling the longitudinal force in accordance with the click.
[0006]
【The invention's effect】
According to the present invention, the contact avoidance braking torque is calculated based on the possibility of contact between the host vehicle and the front object of the host vehicle and the degree of overlap between the front object and the forward travel locus of the host vehicle. Therefore, when the host vehicle starts to change lanes to overtake the front object, the braking force for avoiding contact is caused by the host vehicle approaching the front object. Even in the case of the action, since the magnitude of the contact avoidance braking torque is changed, it is possible to obtain an effect that it is possible to perform the traveling control without feeling uncomfortable for the driver.
[0007]
DETAILED DESCRIPTION OF THE INVENTION
Hereinafter, embodiments of the present invention will be described with reference to the drawings.
FIG. 1 is a schematic configuration diagram showing an embodiment in which the present invention is applied to a rear wheel drive vehicle. In the figure, 1FL and 1FR are front wheels as driven wheels, and 1RL and 1RR are rear wheels as drive wheels. Thus, the driving force of the engine 2 is transmitted to the rear wheels 1RL and 1RR via the automatic transmission 3, the propeller shaft 4, the final reduction gear 5, and the axle 6 to be rotationally driven.
The front wheels 1FL, 1FR and the rear wheels 1RL, 1RR are each provided with a brake actuator 7 composed of, for example, a disc brake that generates a braking force, and the braking hydraulic pressure of these brake actuators 7 is controlled by a braking control device 8. Is done.
[0008]
Here, the braking control device 8 generates a braking hydraulic pressure in response to the depression of the brake pedal 9a, and a braking pressure command value P from a brake control controller 20 described later._BRIn response to this, the brake hydraulic pressure is generated and output to the brake actuator 7. A brake depression amount sensor 9b for detecting the depression amount of the brake pedal 9a is installed in the vicinity of the brake pedal 9a, and a braking torque required by the driver corresponding to the depression amount of the brake pedal 9a (hereinafter referred to as driver requested braking). (Referred to as torque) is calculated with reference to a driver required braking torque calculation map as shown in FIG. This map is set so that when the brake pedal depression amount detected by the brake depression amount sensor 9b increases from 0, the driver requested braking torque also increases from 0 in proportion to this.
[0009]
The engine 2 is provided with an engine output control device 11 that controls the output thereof. Further, the engine 2 has an engine speed N_EAn engine rotation speed sensor 17 for detecting the above is provided. In this engine output control device 11, the depression amount of the accelerator pedal 12a and the throttle opening command value θ from the brake control controller 20 described later.^*Accordingly, the throttle actuator 12 that adjusts the throttle opening provided in the engine 2 is controlled. An accelerator depression amount sensor 12b for detecting the depression amount of the accelerator pedal 12a is installed in the vicinity of the accelerator pedal 12a, and a driving torque required by the driver corresponding to the depression amount of the accelerator pedal 12a (hereinafter, driver requested driving). (Referred to as torque) is calculated with reference to a driver required drive torque calculation map as shown in FIG. This map is set so that when the accelerator pedal depression amount detected by the accelerator depression amount sensor 12b increases from 0, the driver request drive torque also increases from 0 in proportion to this. The driving torque (engine brake torque) when the driver releases his or her foot from the accelerator pedal 12a is the engine speed N detected by the engine speed sensor 17._EIs calculated with reference to the map shown in FIG.
[0010]
Further, a vehicle speed sensor 13 for detecting the host vehicle speed Vs by detecting the rotation speed of the output shaft provided on the output side of the automatic transmission 3 is provided.
On the other hand, a front object sensor 14 as a front object detection means is provided at the lower part of the vehicle body on the front side of the vehicle. The front object sensor 14 is constituted by a scanning laser radar, for example, and periodically irradiates a fine laser beam within a predetermined irradiation range in the forward direction of the vehicle while being shifted by a certain angle in the horizontal direction, and is reflected from the front object. As shown in FIG. 3, the front-rear distance between the host vehicle MC and the front object PC at each angle is based on the time difference from the emission timing to the reception timing of the reflected light. Lx is detected. Further, the lateral distance Ly to the front object PC is detected based on the front-rear distance Lx and the scanning angle, and the width W of the front object PC is also detected.
[0011]
The vehicle is also provided with an accelerator opening sensor 15 for detecting the accelerator opening A and a steering angle sensor 16 for detecting a steering angle δ of a steering wheel (not shown). These detection signals are sent to the brake control controller 20. Entered.
Then, the host vehicle speed Vs output from the vehicle speed sensor 13, the longitudinal distance Lx, the lateral distance Ly, and the width W of the front object output from the front object sensor 14 are input to the brake control controller 20, and this brake control controller. 20, the contact possibility TDD with an object in front of the traveling lane of the host vehicle is calculated, and the overlapping degree P between the front object and the traveling track in front of the host vehicle is calculated. Then, the repulsion torque Tf is calculated according to the contact possibility TDD and the overlapping degree P. The repulsion torque Tf is a contact avoidance braking torque for avoiding contact with a front object, and is added to a driver requested braking / driving torque Td corresponding to the depression amount of the accelerator pedal 12a or the brake pedal 9a to thereby achieve a target driving torque T_W ^*To calculate this target drive torque T_W ^*Braking pressure command value P for realizing_BRAnd target throttle opening θ^*Is output to the braking control device 8 and the engine output control device 11. Here, the repulsion torque Tf is calculated as a negative value.
[0012]
The brake control controller 20 includes a microcomputer and its peripheral devices, and constitutes a control block shown in FIG. 4 according to the software form of the microcomputer.
This control block measures the time from when the front object sensor 14 sweeps the laser beam to when it receives the reflected light of the front object, and calculates the distance Lx and the lateral distance Ly with respect to the front object. Based on the longitudinal distance Lx, the lateral distance Ly, the width W, and the vehicle speed Vs calculated by the unit 21 and the ranging signal processing unit 21, the repulsive torque Tf corresponding to the possibility of contact with the front object and the overlapping degree P is calculated. The repulsive torque calculating unit 40 to calculate, the driver required braking / driving torque calculating unit 25 to calculate the driver required braking / driving torque Td corresponding to the depression amount of the accelerator pedal 12a or the brake pedal 9a, and the repulsive torque calculated by the repulsive torque calculating unit 40. Based on the torque Tf, the driver requested braking / driving torque Td calculated by the driver requested braking / driving torque calculating unit 25 is corrected to obtain the target driving torque T_W ^*The target drive shaft torque calculator 50 for calculating the target drive shaft torque T and the target drive torque T calculated by the target drive shaft torque calculator 50_W ^*Based on the throttle opening command value θ for the throttle actuator 12 and the brake actuator 7_RAnd braking pressure command value P_BRAnd a drive shaft torque control unit 60 that outputs these to the throttle actuator 12 and the brake actuator 7.
[0013]
When the driver is stepping on the accelerator pedal, the driver-requested braking / driving torque calculating unit 25 calculates a driving torque corresponding to the accelerator pedal depression amount detected by the accelerator depression amount sensor 12b as the driver-requested braking / driving torque Td. When the person releases his or her foot from the accelerator pedal and does not step on the brake pedal, the engine speed N detected by the engine speed sensor 17_EIs calculated as the driver requested braking / driving torque Td, and the brake pedal detected by the engine brake torque and the brake depression amount sensor 12b when the driver releases the accelerator pedal and steps on the brake pedal. An added value with the braking torque corresponding to the depression amount is calculated as the driver requested braking / driving torque Td.
[0014]
Further, the target drive shaft torque calculation unit 50 adds the repulsive torque Tf to the driver requested braking / driving torque Td, thereby controlling the braking / driving force so that the braking force is applied to the host vehicle._W ^*To calculate this target drive torque T_W ^*Is output to the drive shaft torque control unit 60. Here, since the repulsive torque Tf is calculated as a negative value, the driver-requested braking / driving torque Td indicated by the solid line in FIG. 5 is corrected by the repulsive torque Tf as indicated by the broken line in FIG.
[0015]
In addition, the drive shaft torque control unit 60 performs the target drive torque T_W ^*Throttle opening command value θ to achieve_RAnd brake fluid pressure command value P_BRAnd the throttle opening command value θ_RIs output to the engine output control device 11 and the brake fluid pressure command value P_BRIs output to the braking control device 8.
The target drive shaft torque calculation unit 50 and the drive shaft torque control unit 60 described above constitute braking / driving force control means.
[0016]
Next, a repulsive torque calculation processing procedure in which the operation of the first embodiment is executed by the repulsive torque calculator 40 will be described with reference to FIG.
This repulsive torque calculation process is executed as a timer interruption process at predetermined time intervals (for example, 10 msec). First, in step S1, the front-rear distance Lx, the lateral distance Ly, and the front object width W detected by the front object sensor 14, The host vehicle speed Vs detected by the vehicle speed sensor 13 is read, and then the process proceeds to step S2 to calculate the contact possibility TDD between the host vehicle and the front object. The contact possibility TDD is an inter-vehicle time obtained by dividing the longitudinal distance Lx from the front object by the own vehicle speed Vs, and is calculated based on the following equation (1).
[0017]
TDD = Lx / Vs (1)
Next, the process proceeds to step S3, where the overlap degree P corresponding to the lateral distance Ly with respect to the front object is calculated with reference to the overlap degree map shown in FIG. The overlapping degree P is a preset width W of the host vehicle._MIf the width W of the front object is equal to the width W of the front object, the width W of the front object is 50% when the lateral distance Ly is W / 2 and 100% when the lateral distance Ly is 0. Is calculated as follows. Here, the lateral distance Ly has the same sign in the left-right direction.
[0018]
Also, the width W of the host vehicle_MWhen the width W of the front object is different from that of the front object, the overlapping degree P is calculated with reference to FIG. In FIG. 7B, the overlapping degree P is set so that the lateral distance Ly is maintained at 100% between 0 and Ly1, and is 50% when Ly = W / 2 and 0% when Ly = Ly2. . Here, Ly1 = (W−W_M) / 2, Ly2 = (W + W_M) / 2. W <W_MIn this case, as shown by the two-dot chain line in FIG.
[0019]
Next, the process proceeds to step S4, where the repulsive torque gain G corresponding to the overlapping degree P calculated in step S3 is calculated with reference to the repulsive torque gain map shown in FIG. The repulsive torque gain G changes linearly with respect to the overlapping degree P, and is calculated to be 0% when the overlapping degree P is 0% and 100% when the overlapping degree P is 100%.
[0020]
Next, the process proceeds to step S5, where the contact possibility TDD calculated in step S2 is a predetermined control intervention threshold TDD.^*It is determined whether or not: TDD ≦ TDD^*If so, the process proceeds to step S6 to calculate the repulsive torque Tf based on the following equation (2). Thereby, the repulsion torque Tf is calculated as a negative value.
Tf = G × K × (TDD−TDD^*) × Vs × α (2)
Here, K is a spring constant, α is a torque conversion coefficient, and each has a predetermined value.
[0021]
On the other hand, the determination result of step S5 is TDD> TDD^*When it is, the process proceeds to step S7 and Tf = 0 is set.
In step S8, the repulsive torque Tf calculated in step S6 or S7 is output to the target drive shaft torque calculation unit 50, and then the timer interruption process is terminated and the process returns to the predetermined main program.
In the process of FIG. 6, the process of step S2 corresponds to the contact possibility index calculating means, the process of step S3 corresponds to the overlap degree detecting means, and the processes of steps S4 to S7 correspond to the contact avoidance braking torque calculating means. is doing.
[0022]
Therefore, as shown in FIG. 9 (a), the contact possibility TDD may become smaller than the control intervention threshold TDD because the distance between the host vehicle and the preceding vehicle is sufficiently wide.^*In a larger state, it is assumed that the vehicle is traveling straight with the preceding vehicle and the forward traveling locus of the host vehicle being matched. In this case, in the repulsive torque calculation process of FIG. 6, the control intervention threshold value TDD in step S2.^*A larger contact possibility TDD is calculated, and then in step S3, the overlap degree P is calculated as 100%. Since the overlapping degree P is 100%, the repulsive torque gain G is also calculated as 100% in step S4. However, TDD> TDD^*Therefore, the process proceeds from step S5 to step S7, the repulsion torque Tf becomes 0, and the driver requested braking / driving torque Td remains as it is as the target driving torque T_W ^*Therefore, the traveling according to the driver's accelerator or brake operation is continued without applying the braking force for avoiding contact with the preceding vehicle.
[0023]
From this state, the host vehicle accelerates, and the inter-vehicle distance from the preceding vehicle becomes narrower as shown in FIG. 9B, and the contact possibility TDD becomes the control intervention threshold TDD.^*In the following, in step S6, the repulsive torque Tf that is a negative value is calculated based on the equation (2).
In step S8, the repulsive torque Tf is output to the target drive shaft torque calculation unit 50, so that the repulsive torque Tf is added to the driver requested drive torque Td corresponding to the driver's accelerator pedal depression amount._W ^*Is calculated, and this target drive torque T_W ^*Braking pressure command value P for realizing_BRAnd target throttle opening θ^*Is output to the braking control device 8 and the engine output control device 11, so that a braking force for avoiding contact with the preceding vehicle acts on the host vehicle.
[0024]
In this state, as shown in FIG. 9C, when the own vehicle starts to change lanes to overtake the preceding vehicle, the overlapping degree P with the preceding vehicle changes due to the turning of the own vehicle. At this time, if the lateral distance Ly detected by the front object sensor 14 is W / 2, the overlap degree P is calculated as 50% in step S3, so the repulsive torque gain G is also calculated as 50% in step S4. Is done. Therefore, in step S6, the repulsion torque Tf is calculated with a magnitude that is about half of the repulsion torque Tf calculated in the state of FIG. 9B, and the vehicle travels in a state where the forward travel locus of the preceding vehicle and the host vehicle coincide. Compared with the case where it is, the braking force for the contact avoidance which acts on the own vehicle is suppressed.
[0025]
If the lane change is further continued from this state, as shown in FIG. 9 (d), when the preceding vehicle and the host vehicle's forward travel locus do not overlap, the overlap degree P is 0% in step S 3. Therefore, the repulsive torque gain G is also calculated as 0% in step S4. Accordingly, since the repulsion torque Tf becomes 0 in step S6, the vehicle returns to traveling according to the driver's accelerator or brake operation.
[0026]
Thus, in the first embodiment, in order to change the magnitude of the repulsive torque according to the degree of overlap between the front object and the forward travel locus of the host vehicle as well as the possibility of contact with the front object, When the vehicle starts to change lanes to overtake the preceding vehicle, the smaller the degree of overlap with the preceding vehicle, the smaller the repulsive torque can be calculated and the driver requested braking / driving torque can be generated more easily. It is possible to suppress a driver's uncomfortable feeling caused by a vehicle approaching a preceding vehicle and applying a braking force for avoiding contact to smoothly change lanes.
[0027]
In the first embodiment, the case where the overlap degree P is calculated with reference to the overlap degree map shown in FIG. 7 has been described. However, the present invention is not limited to this, and the overlap as shown in FIG. The overlapping degree P may be calculated with reference to the degree map. In FIG. 10, the overlapping degree P is set to be 100% when the lateral distance Ly is 0, and to be larger than 50% when the lateral distance Ly is W / 2, and to be reduced to 0%. Thereby, since the overlapping degree P larger than the actual overlapping degree is calculated, the brake control can be operated on the safe side.
[0028]
In the first embodiment, the case where the repulsive torque gain G is calculated with reference to the repulsive torque gain map shown in FIG. 8 has been described. However, the present invention is not limited to this, and as shown in FIG. In addition, referring to the repulsive torque gain map in which the repulsive torque gain G is maintained at 100% until the overlap degree is 80% and the repulsive torque gain G is reduced to 0% between 80% and 0%, The torque gain G may be calculated. Thereby, chattering of the repulsive torque gain due to the accuracy of the lateral distance Ly with respect to the front object can be prevented.
[0029]
Furthermore, in the first embodiment, the case where the repulsive torque gain G is calculated with reference to the repulsive torque gain map shown in FIG. 8 is described, but the present invention is not limited to this, and as shown in FIG. In addition, referring to the repulsive torque gain map in which the repulsive torque gain G is maintained at 100% until the overlapping degree is 50% and the repulsive torque gain G is decreased to 0% between 50% and 0%, The torque gain G may be calculated. Thereby, since the magnitude of the repulsive torque does not change when the degree of overlap with the front object is between 100% and 50%, stable running can be performed with emphasis on the automatic brake function.
[0030]
Next, a second embodiment of the present invention will be described.
In the second embodiment, in the first embodiment described above, the amount of decrease in the rebound torque gain corresponding to the degree of overlap with the front object is changed according to the longitudinal distance Lx with the front object. Is.
FIG. 13 is a flowchart showing a processing procedure of the repulsive torque calculation process executed in the repulsive torque calculation unit 40 in the second embodiment, and in the repulsive torque calculation process in the first embodiment shown in FIG. After step S3, step S201 for setting a repulsive torque gain map according to the longitudinal distance Lx is added, and the process of step S4 calculates the repulsive torque gain G with reference to the repulsive torque gain map set in step S201. 6 except that the processing in step S202 is replaced, and the same parts as those in FIG. 6 are denoted by the same reference numerals, and detailed description thereof is omitted.
[0031]
According to the second embodiment, in step S201, a repulsive torque gain map as shown in FIG. 14A is set according to the longitudinal distance Lx. This repulsive torque gain map shows that the overlap degree P is 100% and a predetermined decrease start point P_SThe rebound torque gain G remains at 100% until the decrease start point P_SIs set so that the repulsive torque gain G decreases as the overlap degree P decreases based on the inclination θ. Here, with reference to FIG. 14B, the inclination θ is calculated so as to increase as the front-rear distance Lx with the front object decreases. Next, the process proceeds to step S202, and the repulsive torque gain G corresponding to the overlapping degree P is calculated with reference to the repulsive torque gain map set in step S201.
[0032]
As described above, in the second embodiment, the repulsive torque gain is set to be limited to a smaller value as the front-rear distance to the front object is smaller. Therefore, the degree of overlap with the preceding vehicle is a predetermined value P._SIn the following cases, the smaller the inter-vehicle distance from the preceding vehicle, the smaller the repulsive torque gain corresponding to the degree of overlap with the preceding vehicle. As a result, when the host vehicle changes lanes with a close distance, the repulsive torque is reduced, so the braking force acting on the host vehicle is suppressed and the lanes are changed smoothly. Can do.
[0033]
Next, a third embodiment of the present invention will be described.
In the third embodiment, the amount of decrease in the rebound torque gain corresponding to the degree of overlap with the front object is changed according to the accelerator opening A in the first embodiment described above. .
FIG. 15 is a flowchart showing a processing procedure of the repulsive torque calculation process executed in the repulsive torque calculation unit 40 in the third embodiment. In the repulsive torque calculation process in the first embodiment shown in FIG. After step S3, step S301 for setting a repulsive torque gain map in accordance with the accelerator opening A is added. In step S4, the repulsive torque gain G is set by referring to the repulsive torque gain map set in step S301. The same processing as in FIG. 6 is performed except that the calculation is replaced with the processing in step S302. The same parts as those in FIG. 6 are denoted by the same reference numerals, and detailed description thereof is omitted.
[0034]
According to the third embodiment, in step S301, a repulsive torque gain map as shown in FIG. This repulsive torque gain map shows that the overlap degree P is 100% and a predetermined decrease start point P_SThe rebound torque gain G remains at 100% until the decrease start point P_SIs set so that the repulsive torque gain G decreases as the overlap degree P decreases based on the inclination θ. Here, with reference to FIG. 16B, the inclination θ is calculated so as to increase as the accelerator opening A increases. Next, the process proceeds to step S302, where the repulsive torque gain G corresponding to the overlapping degree P is calculated with reference to the repulsive torque gain map set in step S301.
[0035]
As described above, in the third embodiment, since the repulsive torque gain is set to be smaller as the accelerator opening is larger, the degree of overlap with the preceding vehicle is the predetermined value P._SIn the following cases, the repulsive torque gain corresponding to the degree of overlap with the preceding vehicle is calculated to be small. As a result, when the own vehicle changes lanes and the driver steps on the accelerator to accelerate to overtake the preceding vehicle, the repulsive torque is reduced, so that The braking force to be suppressed is suppressed, and the lane change can be performed smoothly.
Next, a fourth embodiment of the present invention will be described.
In the fourth embodiment, in the first embodiment described above, the amount of decrease in the rebound torque gain corresponding to the degree of overlap with the front object is changed in accordance with the steering angular velocity Δδ.
[0036]
FIG. 17 is a flowchart showing a processing procedure of the repulsive torque calculation process executed in the repulsive torque calculation unit 40 in the fourth embodiment, and in the repulsive torque calculation process in the first embodiment shown in FIG. Step S401 for calculating the steering angular velocity Δδ from the steering angle δ detected by the steering angle sensor 16 after step S3 and step S402 for setting a repulsive torque gain map according to the steering angular velocity Δδ are added, and the processing of step S4 Is the same as FIG. 6 except that it is replaced with the process of step S403 for calculating the repulsive torque gain G with reference to the repulsive torque gain map set in step S402. The same reference numerals are given to the parts, and detailed description thereof is omitted.
[0037]
The steering angle sensor 16 and the processing in step S401 in FIG. 17 correspond to the steering angular velocity detection means.
According to the fourth embodiment, the steering angular velocity Δδ is calculated by differentiating the steering angle δ detected by the steering angle sensor 16 in step S401, and then, in step S402, FIG. Set a repulsive torque gain map as shown in This repulsive torque gain map shows that the overlap degree P starts from 100% and starts to decrease P_SThe rebound torque gain G remains at 100% until the decrease start point P_SIs set so that the repulsive torque gain G decreases to 0% when the overlap degree P is 0%. Here, the decrease start point P_SIs the offset value P_offSet by Offset value P_offReferring to FIG. 16 (b), the offset value P is calculated so as to increase as the steering angular velocity Δδ increases._offDecrease start point P when is 0_SLet P = 50%. Next, the process proceeds to step S403, and the repulsive torque gain G corresponding to the overlapping degree P is calculated with reference to the repulsive torque gain map set in step S402.
[0038]
As described above, in the fourth embodiment, as the steering wheel angular velocity increases, the repulsion torque gain corresponding to the degree of overlap with the preceding vehicle is calculated to be smaller. Therefore, when the host vehicle changes lanes, Since the repulsive torque corresponding to the degree of overlap is calculated to be smaller as the person's steering wheel operation is faster, the braking force acting on the host vehicle is suppressed, and the lane change can be performed smoothly.
[0039]
Further, when the host vehicle is traveling straight without performing a steering operation, the repulsive torque gain is maintained at 100% until the degree of overlap with the preceding vehicle reaches 50%. Thus, even when the degree of overlap changes due to a change in the lateral distance from the preceding vehicle, fluctuations in the repulsive torque gain can be suppressed to ensure stable running.
[0040]
In the fourth embodiment, the steering angular velocity Δδ is calculated by differentiating the steering angle δ in step S401. However, the present invention is not limited to this, and the steering angle δ per unit time is described. Alternatively, the steering angular velocity Δδ may be calculated from the amount of change.
Next, a fifth embodiment of the present invention will be described.
In the fifth embodiment, in the first embodiment described above, the reduction change amount of the repulsive torque gain according to the degree of overlap with the front object is changed in accordance with the interruption determination of the own vehicle. is there.
[0041]
FIG. 19 is a flowchart showing a processing procedure of the repulsive torque calculation process executed in the repulsive torque calculation unit 40 in the fifth embodiment, and in the repulsive torque calculation process in the first embodiment shown in FIG. After step S3, step S501 for determining the interruption of the own vehicle and step S502 for setting a repulsive torque gain map according to the determination of the interruption of the own vehicle are added, and the processing of step S4 is performed in the repulsion set in step S502. The same processing as in FIG. 6 is performed except that the processing in step S503 for calculating the repulsive torque gain G with reference to the torque gain map is performed, and the same parts as those in FIG. Detailed description is omitted.
[0042]
In the process of FIG. 19, the process of step S501 corresponds to the interrupt determination means.
According to the fifth embodiment, in step S501, it is determined whether or not the host vehicle has changed lanes and has interrupted the preceding vehicle in the adjacent lane. This determination is performed using a winker signal or a steering angle δ by a driver's operation, and the steering angle δ is set in advance by a steering angle setting value δ._SWhen the winker instruction direction and the steering direction coincide with each other as described above, it is determined that the host vehicle changes lanes. Furthermore, at this time, when the front object is detected by the front object sensor 14 and the speed Vp of the front object is higher than the own vehicle speed Vs, it is determined that the vehicle has interrupted the preceding vehicle traveling at a speed higher than the own vehicle speed Vs. To do. Here, the front object speed Vp is calculated from the relative speed Vr detected by the front object sensor 14 and the host vehicle speed Vs.
[0043]
Next, in step S502, a repulsive torque gain map as shown in FIG. 20 is set according to the interrupt determination of the host vehicle. This repulsive torque gain map shows that the overlap degree P starts from 100% and starts to decrease P_SThe rebound torque gain G remains at 100% until the decrease start point P_SIs set so that the repulsive torque gain G decreases to 0% when the overlap degree P is 0%. Here, the decrease start point P_SIs the offset value P_offSet by Offset value P_offIs set to be a large value when it is determined that the host vehicle has changed the lane and interrupted the adjacent lane, and this offset value P_offDecrease start point P when is 0_SLet P = 50%. Next, the process proceeds to step S503, and the repulsive torque gain G corresponding to the overlap degree P is calculated with reference to the repulsive torque gain map set in step S502.
[0044]
As described above, in the fifth embodiment, it is determined whether or not the own vehicle has changed lanes and has interrupted the preceding vehicle in the adjacent lane. When it is determined that the own vehicle has interrupted, the vehicle overlaps with the preceding vehicle. Since the repulsive torque gain corresponding to the degree is calculated to be small, when the driver himself interrupts the preceding vehicle, the driver recognizes the preceding vehicle, so that the braking force for avoiding contact with the preceding vehicle is increased. It is possible to suppress a sense of incongruity due to the action, and when the preceding vehicle has interrupted in front of the own vehicle, the repulsive torque gain is calculated larger than when the own vehicle has interrupted the preceding vehicle. Thus, it is possible to ensure the safe driving by reliably applying the braking force.
[0045]
Next, a sixth embodiment of the present invention will be described.
In the sixth embodiment, in the first embodiment described above, the amount of change in the rebound torque gain corresponding to the degree of overlap with the front object is changed in accordance with the vehicle lane. .
As shown in FIG. 21, the schematic configuration of the sixth embodiment is the same as that shown in FIG. 1 except that a CCD camera 18 and a camera controller 19 are provided as an external recognition sensor for detecting the traveling lane of the host vehicle. Since it has the same configuration, the same reference numerals are assigned to the parts corresponding to those in FIG. 1, and the detailed description thereof is omitted.
The camera controller 19 detects a lane marker such as a road marking line from a captured image in front of the host vehicle captured by the CCD camera 18, and determines the lane type (running lane or overtaking lane) on which the host vehicle is traveling. At the same time, it determines the curve state (right curve or left curve) of the lane in which the host vehicle is traveling, and further detects the lane curvature β.
[0046]
FIG. 22 is a flowchart showing a processing procedure of the repulsive torque calculation process executed in the braking control controller 20 in the sixth embodiment. In the repulsive torque calculation process in the first embodiment shown in FIG. Step S601 for determining the vehicle lane after step S2, Step S602 for determining whether the vehicle lane is a right curve, and whether the vehicle lane is a right curve entrance Step S603 to set an overlap degree map according to the lane curvature change amount when the vehicle is at the right curve entrance, and set an overlap degree map according to the lane curvature change amount when the vehicle is at the right curve exit Step S605 and a step of determining whether or not the host vehicle lane is the left curve entrance when the host vehicle lane is not a right curve. Step S607 for setting the overlap degree map according to the lane curvature change amount when the vehicle is at the left curve entrance, and setting the overlap degree map according to the lane curvature change amount when the vehicle is at the left curve exit Step S608 and step S609 for setting a repulsive torque gain map according to the travel lane (whether the travel lane or the overtaking lane) are added, and the process of step S3 is any one of steps S604, S605, S607, and S608. Step S610 of calculating the overlapping degree P with reference to the overlapping degree map set in step S610 is replaced, and the process of step S4 calculates the repulsive torque gain G with reference to the repulsive torque gain map set in step S609. The same processing as that in FIG. 6 is performed except that the processing is replaced with the processing in S611. Imparting to the detailed description of the same reference numerals in part will be omitted.
[0047]
In the process of FIG. 22, the process of step S601 corresponds to the travel lane determining means.
According to the sixth embodiment, when the host vehicle is traveling on the traveling lane at the right curve entrance, the type of lane (traveling lane) that the host vehicle is traveling detected by the camera controller 19 in step S601. The lane curve state (right curve) and the lane curvature β are read. Next, the process proceeds to step S602, where it is determined whether or not the vehicle lane is a right curve.
[0048]
If the determination result in step S602 is that the vehicle lane is a right curve, the process proceeds to step S603 to determine the entrance / exit of the curve. This determination is made based on the amount of change in the traveling lane curvature β. When the amount of curvature change is on the decrease side, it is determined that the vehicle is on the right curve entrance, and when the amount of curvature change is on the increase side, it is determined that the vehicle is on the right curve exit. To do. When the host vehicle travel lane is the right curve entrance, the process proceeds to step S604, and an overlapping degree map as shown in FIG. 23 is set. Here, as shown in FIG. 24, the lateral distance Ly with respect to the front object is assumed to have a different sign on the right and left, and becomes a positive value when the forward travel locus of the host vehicle is shifted to the right with respect to the front object. When it is shifted to the left, it becomes a negative value. Further, the offset value Ly shown in FIG._offIs calculated with reference to FIG. 25A according to the amount of change in lane curvature. Therefore, the offset value Ly_offIs negative at the entrance to the right curve. If the result of the determination in step S603 is that the host vehicle lane is a right curve exit, the process proceeds to step S605 and an overlap degree map as shown in FIG. 23 is set. Here, the offset value Ly_offIs calculated with reference to FIG. 25A according to the amount of change in lane curvature. Therefore, the offset value Ly_offIs positive at the right curve exit.
[0049]
On the other hand, when the determination result in step S602 indicates that the host vehicle lane is not a right curve, the process proceeds to step S606, and the curve entrance / exit determination is performed. This determination is made based on the amount of change in the travel lane curvature β. When the amount of curvature change is on the increase side, it is determined to be the left curve entrance, and when the amount of curvature change is on the decrease side, it is determined to be the left curve exit. To do. When the host vehicle lane is at the left curve entrance, the process proceeds to step S607, and an overlap degree map as shown in FIG. 23 is set. Here, the offset value Ly_offIs calculated with reference to FIG. 25B according to the amount of change in lane curvature. Therefore, the offset value Ly_offIs positive at the left curve entrance. If the result of the determination in step S606 is that the host vehicle lane is a left curve exit, the process proceeds to step S608 and an overlap degree map as shown in FIG. 23 is set. Here, the offset value Ly_offIs calculated with reference to FIG. 25B according to the amount of change in lane curvature. Therefore, the offset value Ly_offIs negative at the left curve exit.
[0050]
Thereby, at the right curve entrance or the left curve exit, the offset value Ly_off26 is a negative value, an overlap degree map in which the overlap degree with respect to the left side of the front object is changed as shown in FIG. 26A is set, and the offset value Ly is set at the right curve exit or the left curve entrance._offSince this becomes a positive value, as shown in FIG. 26B, an overlap degree map is set in which the overlap degree with respect to the right side of the front object is changed.
[0051]
Next, the process proceeds to step S609, and a repulsive torque gain map as shown in FIG. 27 is set according to the host vehicle lane. This repulsive torque gain map shows that the overlap degree P starts from 100% and starts to decrease P_SThe rebound torque gain G remains at 100% until the decrease start point P_SIs set so that the repulsive torque gain G decreases to 0% when the overlap degree P is 0%. Here, the decrease start point P_SIs the offset value P_offSet by Offset value P_offIs set to 0 when the host vehicle is traveling on the overtaking lane, and is set to a large value when the host vehicle is traveling on a traveling lane adjacent to the overtaking lane. Also, the offset value P_offDecrease start point P when the vehicle is 0, that is, when the vehicle is driving on the overtaking lane_SLet P = 50%.
[0052]
Next, in step S610, the overlap degree P is calculated with reference to the overlap degree map set in any of steps S604, S605, S607, and S608, and then in step S611, the repulsive torque gain map set in step S609. , The repulsive torque gain G corresponding to the overlapping degree P is calculated.
[0053]
Therefore, when the host vehicle is traveling on the traveling lane of the right curve entrance, even when the traveling track of the host vehicle is slightly shifted to the left side from the preceding vehicle, FIG. As shown, since the overlap degree P is calculated as 100%, the rebound torque is reduced even when the negative vehicle lateral distance Ly is detected when the preceding vehicle starts turning at the right curve entrance first. In order to safely generate a braking force for avoiding contact and to change the lane to the overtaking lane adjacent to the own vehicle lane, When deviated, the repulsive torque gain G corresponding to the degree of overlap P with the preceding vehicle is calculated smaller than when traveling on the overtaking lane as shown in FIG. Control the braking force It is possible to carry out the running with no discomfort to the person.
[0054]
As described above, in the sixth embodiment, the type of lane in which the host vehicle is traveling is determined, and when the host vehicle is traveling in a traveling lane that may change the lane, it overlaps with the preceding vehicle. Since the repulsive torque gain corresponding to the degree is calculated to be small, the repulsive torque is reduced when the host vehicle changes lanes, so that the braking force for avoiding contact with the preceding vehicle is suppressed and smooth. You can change lanes.
[0055]
In addition, the curve situation of the host vehicle lane is judged, and the degree of overlap with the front object is changed according to the amount of change in the lane curvature. By changing the degree of overlap with respect to, it is possible to suppress a decrease in repulsive torque with respect to the degree of overlap on the left side, and when the host vehicle is running on the left curve, by changing the degree of overlap on the right side at the curve entrance, A reduction in repulsion torque with respect to the degree of overlap on the right side can be suppressed, and safe cornering can be ensured.
[0056]
In each of the above embodiments, the case where the overlap degree P is directly calculated using the lateral distance Ly with the front object detected by the front object sensor 14 is described, but the present invention is not limited to this. By detecting the lane curvature of the traveling lane and correcting the lateral distance Ly with respect to the front object in consideration of the lane curvature, the overlap degree P is calculated. It can be calculated accurately.
[0057]
In each of the above embodiments, the case where the laser radar is used as the front object sensor 14 has been described. However, the present invention is not limited to this, and a millimeter wave radar or the like may be applied. You may make it detect the information of a front object by processing the image which imaged the front.
Further, in each of the above embodiments, the case where the present invention is applied to a rear wheel drive vehicle has been described. However, the present invention can also be applied to a front wheel drive vehicle, and the case where the engine 2 is applied as a rotational drive source. Although explained, it is not limited to this, An electric motor can also be applied, Furthermore, this invention is applicable also to the hybrid specification vehicle which uses an engine and an electric motor.
[Brief description of the drawings]
FIG. 1 is a schematic configuration diagram showing an embodiment of the present invention.
FIG. 2 is an explanatory diagram of braking / driving torque corresponding to an accelerator or brake pedal depression amount.
FIG. 3 is an explanatory diagram of a front object sensor.
4 is a block diagram showing a specific example of the brake control controller of FIG. 1. FIG.
FIG. 5 is an explanatory diagram of braking / driving force control executed by a target drive shaft torque calculation unit in FIG. 4;
FIG. 6 is a flowchart showing a repulsive torque calculation process executed by the brake control controller in the first embodiment.
FIG. 7 is an overlapping degree map.
FIG. 8 is a repulsive torque gain map in the first embodiment.
FIG. 9 is a diagram for explaining the operation of the first embodiment;
FIG. 10 is another example of the overlapping degree map.
FIG. 11 is another example of a repulsive torque gain map in the first embodiment.
FIG. 12 is another example of a repulsive torque gain map in the first embodiment.
FIG. 13 is a flowchart showing a repulsive torque calculation process executed by the braking control controller in the second embodiment.
FIG. 14 is a repulsive torque gain map in the second embodiment.
FIG. 15 is a flowchart showing a repulsive torque calculation process executed by a braking control controller according to a third embodiment.
FIG. 16 is a repulsive torque gain map in the third embodiment.
FIG. 17 is a flowchart showing a repulsive torque calculation process executed by a braking control controller according to a fourth embodiment.
FIG. 18 is a repulsive torque gain map in the fourth embodiment.
FIG. 19 is a flowchart showing a repulsive torque calculation process executed by a braking control controller according to a fifth embodiment.
FIG. 20 is a repulsive torque gain map in the fifth embodiment.
FIG. 21 is a schematic configuration diagram showing an embodiment of the present invention.
FIG. 22 is a flowchart showing a repulsive torque calculation process executed by the braking control controller in the sixth embodiment.
FIG. 23 is an overlap degree map in the sixth embodiment.
FIG. 24 is an explanatory diagram of a lateral distance from a front object.
FIG. 25 is a calculation map of an offset value according to the curvature in the sixth embodiment.
FIG. 26 is an explanatory diagram of an overlap degree map according to the sixth embodiment.
FIG. 27 is a repulsive torque gain map in the sixth embodiment.
[Explanation of symbols]
2 Engine
3 Automatic transmission
7 Disc brake
8 Braking control device
11 Engine output control device
12 Throttle actuator
13 Vehicle speed sensor
14 Front object sensor
15 Accelerator position sensor
16 Steering angle sensor
17 Engine rotation speed sensor
20 Brake control controller
25 Driver requested braking / driving torque calculation unit
40 Repulsive torque calculator
50 Target drive shaft torque calculator
60 Drive shaft torque controller

Claims (9)

A forward object detection means for detecting an object ahead of the host vehicle, a vehicle speed detection means for detecting the vehicle speed of the host vehicle, a relative distance between the forward object detected by the forward object detection means and the host vehicle speed detected by the vehicle speed detection means. Based on the above, the contact possibility index calculating means for calculating the contact possibility with the forward object, and the overlap degree detection for detecting the overlap degree between the forward object detected by the forward object detecting means and the forward travel locus of the host vehicle A contact avoidance braking torque calculating means for calculating a contact avoidance braking torque based on the contact possibility calculated by the contact possibility index calculating means and the overlap degree detected by the overlap degree detecting means, and the contact avoidance braking torque And an automatic braking force control means for controlling the braking / driving force in accordance with the contact avoidance braking torque calculated by the calculating means and the braking / driving torque by the operation of the driver. Rk in the controller. The automatic contact avoidance braking torque is configured so that the contact avoidance braking torque decreases as the overlap degree detected by the overlap degree detection means decreases. Brake control device. The contact avoidance braking torque calculating means decreases the contact avoidance braking torque calculated based on the degree of overlap detected by the overlap degree detecting means as the relative distance from the front object detected by the front object detecting means decreases. The automatic brake control device according to claim 2, wherein the automatic brake control device is limited to The contact avoidance braking torque calculation means is configured to limit the contact avoidance braking torque calculated based on the overlap degree detected by the overlap degree detection means to a smaller value as the accelerator amount operated by the driver increases. The automatic brake control device according to claim 2, wherein the automatic brake control device is provided. Steering angular velocity detecting means for detecting the steering angular speed of the steering angle of the driver's steering wheel, and the contact avoidance braking torque calculating means is detected by the overlap degree detecting means as the steering angular speed detected by the steering angular speed detecting means increases. The automatic brake control device according to claim 2, wherein the contact avoidance braking torque calculated based on the degree of overlap is limited to a small value. When there is an interrupt determination means for determining that the host vehicle has changed into a lane and has interrupted an adjacent lane, and the contact avoidance braking torque calculation means has determined by the interrupt determination means that the host vehicle has interrupted an adjacent lane Further, the contact avoidance braking torque calculated based on the overlap degree detected by the overlap degree detecting means is limited to a value smaller than the contact avoidance braking torque during other travel. The automatic brake control device according to claim 2, wherein Traveling lane determining means for detecting lane information in which the host vehicle is traveling is provided, and the contact avoidance braking torque calculating means causes the traveling vehicle to travel on a traveling lane adjacent to the overtaking lane by the traveling lane determining means. So that the contact avoidance braking torque calculated based on the overlap degree detected by the overlap degree detecting means is limited to a value smaller than the contact avoidance braking torque during driving in the overtaking lane. The automatic brake control device according to claim 2, wherein the automatic brake control device is configured. The contact avoidance braking torque calculation means determines the degree of overlap with respect to the left side of the front object detected by the overlap degree detection means at the entrance of the curve when the travel lane determination means determines that the host vehicle lane is a right curve. And a decrease in the contact avoidance braking torque calculated based on the degree of overlap with respect to the right side of the front object detected by the overlap degree detection means at the curve exit. The automatic brake control device according to claim 7, which is configured as described above. The contact avoidance braking torque calculation means determines the degree of overlap with respect to the right side of the front object detected by the overlap degree detection means at the entrance of the curve when the travel lane determination means determines that the host vehicle lane is a left curve. And a decrease in the contact avoidance braking torque calculated based on the degree of overlap with respect to the left side of the front object detected by the overlap degree detection means at the curve exit. 9. The automatic brake control device according to claim 7, wherein the automatic brake control device is configured as described above.

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