JP4980773B2 - Vehicle travel safety device - Google Patents

Description

  The present invention relates to a vehicle travel safety device, and more specifically to an apparatus that detects an obstacle such as a preceding vehicle around a vehicle (own vehicle) and assists in avoiding contact with the obstacle.

A radar with electromagnetic waves is mounted on the vehicle to detect and recognize obstacles such as a preceding vehicle ahead, judge the possibility of contact with the obstacle, and if it is judged that there is a possibility of contact, warning and steering An apparatus that performs a contact avoidance assist operation with an obstacle by vehicle control such as the above is known, and the technique described in Patent Document 1 below, which has been previously proposed by the present applicant, can be given as an example. In the prior art, when an obstacle (an oncoming vehicle) is approaching the vehicle, the vehicle is controlled so that it is difficult for the vehicle to deviate from the proper course.
JP 2006-131072 A

  In the conventional technology described above, contact avoidance is supported by controlling the vehicle so that it is difficult for the vehicle to deviate from the proper course. However, if there is a possibility of contact with an obstacle anyway, a driver is alerted. When the driver is prompted to perform an avoidance operation or assist the avoidance steering, the start of the avoidance operation may be delayed if the driver holds the steering wheel in a relaxed state.

  Therefore, the object of the present invention is to solve the above-described problems, and when it is determined that there is a possibility of contact with an obstacle, the driver can apply steering torque to the driver before performing the contact avoidance support operation. Even when the steering wheel is gripped in a relaxed state, it is an object of the present invention to provide a vehicle travel safety device that prevents the start of an avoidance operation from being delayed by calling attention.

  In order to solve the above-mentioned object, in claim 1, an object detection means for detecting an object existing around a vehicle, a movement state detection means for detecting a movement state of the vehicle, and the detected Contact possibility determination means for determining the possibility of contact with the detected object based on a motion state, and contact with the detected object when it is determined that there is a possibility of contact with the object In a vehicle travel safety device comprising contact avoidance support means for performing an avoidance support operation, a predetermined time in a direction opposite to the direction of the vehicle avoiding from the object before the contact avoidance support means performs the contact avoidance support operation A steering torque applying means for applying a steering torque is provided.

  The vehicle safety device according to claim 2 is configured such that the predetermined time is a time that does not affect the behavior of the vehicle and is perceptible to the driver.

  In the vehicle travel safety device according to claim 3, the predetermined time is configured to be a time between 50 msec and 100 msec.

  In the vehicle travel safety device according to claim 1, since the steering torque is applied for a predetermined time in a direction opposite to the direction in which the vehicle avoids from the object before performing the contact avoidance support operation, the driver is in a relaxed state. Even when the steering wheel is gripped, it is possible to cause a reflexive reaction to try to steer in the direction opposite to the direction of the steering torque applied unconsciously. In other words, it is possible to induce a reflexive reaction that prompts the driver's attention and tries to steer quickly in the avoidance direction, so that the start of the avoidance operation is not delayed.

  In the vehicle travel safety device according to claim 2, since the predetermined time is configured so as not to affect the behavior of the vehicle and to be perceivable by the driver, in addition to the effects described above, the vehicle The driver's attention can be alerted without affecting the behavior of the driver.

  In the vehicle travel safety device according to claim 3, since the predetermined time is configured to be a time between 50 msec and 100 msec, as in claim 2, the driver's behavior is not affected. You can call attention.

  The best mode for carrying out a vehicle travel safety device according to the present invention will be described below with reference to the accompanying drawings.

  FIG. 1 is a schematic diagram showing the overall travel safety device for a vehicle according to a first embodiment of the present invention.

  In FIG. 1, reference numeral 10 denotes a vehicle travel safety device. The device 10 transmits the driving force of an internal combustion engine (shown as “ENG” in the figure, hereinafter referred to as “engine”) 12 to an automatic transmission (in the figure, “T / M ”) 14 is mounted on a vehicle (own vehicle, not shown) that transmits to drive wheels (not shown), a control device 16, a brake actuator 20, an EPS (Electric Power Steering) actuator 22, An alarm device 24 is provided.

  The control device 16 includes a travel control unit 26, an engine control unit 30, a shift control unit 32, a brake control unit 34, and an EPS control unit 36. All of these control units include a microcomputer and are configured to be able to communicate with each other.

  The travel control unit 26 functions as a contact avoidance support unit that performs a contact avoidance support operation, which will be described later. The engine control unit 30 and the shift control unit 32 control the operations of the engine 12 and the automatic transmission 14, but the operations of the engine control unit 30 and the shift control unit 32 are not directly related to the subject matter of the present application. Is omitted.

  The brake actuator 20 generates a braking pressure with a master back (not shown) that increases the depression force of a brake pedal (not shown) and the increased depression force, and passes through a brake hydraulic mechanism (not shown). It consists of a master cylinder (not shown) that operates brakes mounted on the drive wheels and driven wheels.

  The brake control unit 34 is connected to the brake actuator 20. In response to a command from the travel control unit 26, the brake control unit 34 performs automatic braking that operates the brake actuator 20 independently of the driver's (driver) brake pedal operation via the brake hydraulic mechanism. Is braked (decelerated).

  The EPS actuator 22 will be described by taking the case where the front wheel is a drive wheel as an example. The EPS actuator 22 reciprocates a rack (not shown) via a pinion to rotate the steering wheel (not shown) transmitted from a steering shaft or the like. In a mechanism for converting the front wheel through a tie rod (not shown), the motor is arranged on the rack.

  The EPS control unit 36 is connected to the EPS actuator 22. The EPS control unit 36 operates the EPS actuator 22 in accordance with a command from the travel control unit 26 to apply a steering torque to the driver.

  The alarm device 24 includes an audio speaker and an indicator (both not shown) installed near the driver's seat of the vehicle, and is connected to the travel control unit 26. The traveling control unit 26 activates the alarm device 24 to alert the driver through sound and vision.

  The travel control unit 26 further pulls in the seat belt via a drive mechanism of a seat belt (not shown) disposed in the driver's seat of the vehicle, or the EPS actuator 22 via the EPS control unit 36 as necessary. The driver is also warned by operating and vibrating the steering wheel.

  In addition to the above, the device 10 includes sensors as shown.

  As will be described below, the photographing apparatus 40 includes a camera 40a formed of a CCD camera or a C-MOS camera and an image processing unit 40b. The camera 40a is disposed at a position in the vicinity of the rearview mirror on the vehicle interior side of the front window of the vehicle, and photographs the front in the traveling direction through the front window. The image processing unit 40b inputs an image obtained by photographing with the camera 40a, performs image processing such as filtering and binarization, generates image data, and outputs the image data to the traveling control unit 26.

  The radar device 42 includes a radar 42a such as a laser beam or a millimeter wave and a radar control unit 42b. The radar 42a is disposed in the nose portion of the vehicle body and transmits laser light and the like around the vehicle in the traveling direction in accordance with an instruction from the radar control unit 42b that operates according to a command from the travel control unit 26. The reflected signal generated by the reflection of the object existing around the vehicle is received and mixed with the transmission signal to generate a beat signal, which is output to the traveling control unit 26.

  The steering torque sensor 44 is disposed between the steering wheel and the EPS actuator 22 and generates an output corresponding to the direction and magnitude of the steering force (steering torque) input (operated) by the driver from the steering wheel.

  The steering angle sensor 46 is disposed in the vicinity of the steering shaft, and generates an output corresponding to the direction and magnitude of the steering angle input (operated) by the driver through the steering wheel.

  The yaw rate sensor 50 is disposed in the vicinity of the center of gravity of the vehicle, and generates an output corresponding to the yaw rate (rotational angular velocity) around the vertical axis (yaw axis) of the vehicle.

  The vehicle speed sensor 52 is disposed in the vicinity of a drive shaft (not shown) of the drive wheel, and outputs a pulse every predetermined rotation of the drive wheel. The output of the above-described sensor is also sent to the travel control unit 26, and the travel control unit 26 detects the steering torque and the like from those input values, and counts the output of the vehicle speed sensor 52 to detect the vehicle speed.

  FIG. 2 is a flowchart showing the contact avoidance support operation of the travel control unit 26 in the device 10 shown in FIG. 1, more specifically, the control device 16 of the device 10.

  In the following, in S10, an object (such as a preceding vehicle) around the vehicle (own vehicle) is detected based on the output of the imaging device 40 or the radar device 42, and the relative position and relative speed with respect to the vehicle are detected. Next, in S12, the course of the vehicle is estimated from the vehicle speed and the yaw rate.

  Next, in S14, the possibility of contact is determined from the relationship between the relative position to the object, the relative speed, and the vehicle path, and the object that may be contacted is recognized as an obstacle. For example, as shown in FIG. 3, the vehicle 100 and the object 102 are based on the estimated predicted path of the vehicle (indicated by reference numeral 100) and the predicted path of the object 102 predicted from the change in the position of the object (indicated by reference numeral 102). Estimate the predicted position of the vehicle 100 and the predicted position of the object 102 at which the distance between them is zero, and calculate the lap amount 104 thereof. If the lap amount 104 is greater than or equal to a predetermined value, it is determined that there is a possibility of contact. , Recognize as an obstacle.

  Next, the process proceeds to S16, where it is determined that contact avoidance is difficult, in other words, whether there is a possibility of contact. If the determination is affirmative, the process proceeds to S18, and the contact avoidance support timing is calculated according to the lap amount described above. In S20, the contact avoidance support distance is calculated by multiplying the value calculated in S18 by the relative speed detected in S10.

  Next, in S22, a target course is calculated. That is, as shown in FIG. 4, the left avoidance amount for avoiding to the left of the obstacle 102 and the right avoidance amount for avoiding to the right as the target course for avoiding contact are calculated, and the avoidance amount is small. In the illustrated example, the right direction is calculated (determined) as the target course.

  Next, the process proceeds to S24, in which it is determined whether or not the relative distance is less than the contact avoidance support distance. As shown in FIG. 5, the steering torque is in a direction opposite to the steering direction of the target course, in other words, in a direction opposite to the direction in which the vehicle (own vehicle) 100 avoids from the obstacle (object) 102 for a predetermined time or a predetermined time. Assign a value less than the value.

  Steering torque is such that even if the driver is gripping the steering wheel in a relaxed state, the driver's attention should be such that it causes a reflexive reaction to steer in the direction opposite to the direction of the steering torque applied unconsciously. Is given to such an extent that a reflex reaction is caused to quickly steer in the avoidance direction, that is, the gripping state of the driver is changed from the relaxed state to the tensioned state.

  The predetermined time is a time that does not affect the behavior of the vehicle (own vehicle) and can be perceived by the driver, and more specifically is a time between 50 msec and 100 msec.

  The predetermined value is specifically a value correlated with a road surface reaction force during normal traveling of the vehicle 100, for example, a value similar to the road surface reaction force, specifically, a value between 5 kgfcm and 15 kgfcm, or a driver's steering force The value is between 0.25 kgf and 0.75 kgf. The predetermined value may be further reduced so as to stimulate the hand or arm holding the steering wheel.

  As shown by a broken line in FIG. 6, the steering torque may be continuously applied without being limited to a predetermined time. Further, as indicated by a solid line in FIG. 2, the steering torque may be applied in the direction to avoid after the obstacle 102 is applied in the direction opposite to the direction in which the vehicle 100 avoids.

  As is apparent from the above, the steering torque may be given an appropriate value for a predetermined time in a direction opposite to the direction in which the vehicle 100 avoids from the obstacle 102, or torque less than the predetermined value may be applied for a predetermined time. In other words, the torque may be applied continuously or at different times, and further, a torque having a predetermined value or less may be applied for a predetermined time.

  Returning to the description of FIG. 2, the process then proceeds to S <b> 28 to execute a contact avoidance support operation. As the contact avoidance assisting operation, an audio or visual alarm is executed via the alarm device 24.

  In S28, the steering torque may be controlled via the EPS control unit 36 and the EPS actuator 22 so as to be the above-described target course in addition to or instead of that, and in addition to the steering control, the brake control may be performed. Brake assist such as decelerating the vehicle 100 by operating an automatic brake via the part 34 and the brake actuator 20 may be performed.

  Since the steering torque is applied in S26 before the contact avoidance assist operation is performed in S28, the start of the avoidance operation is not delayed even when the driver is holding the steering wheel in a relaxed state. When negative in S16 and S24, the subsequent processing is skipped.

  As described above, in the vehicle travel safety device according to the first embodiment, the vehicle (own vehicle) 100 is directed away from the obstacle (object) 102 before the contact avoidance assist operation is performed. Since the steering torque is applied for a predetermined time or less than a predetermined value, even if the driver is gripping the steering wheel in a relaxed state, try to steer in the direction opposite to the direction of the steering torque applied unconsciously. It is possible to induce a reflex reaction. In other words, it is possible to induce a reflexive reaction that prompts the driver's attention and tries to steer quickly in the avoidance direction, so that the start of the avoidance operation is not delayed.

  In addition, since the predetermined time is configured to be a time that does not affect the behavior of the vehicle 100 and is perceivable by the driver, specifically a time between 50 msec and 100 msec, in addition to the above effects, the vehicle The driver's attention can be alerted without affecting the 100 behavior.

  In addition, before performing the contact avoidance support operation, the steering torque of a predetermined value or less is applied from the object 102 in the direction opposite to the direction in which the vehicle 100 avoids, so that the driver holds the steering wheel in a relaxed state. Even in such a case, it is possible to cause a reaction to hold the applied steering torque unconsciously. That is, the gripping state of the driver can be changed from the relaxed state to the tensioned state, so that the start of the avoidance operation is not delayed.

  Further, since the predetermined value is configured to correlate with the road surface reaction force during travel of the vehicle 100, in addition to the above-described effects, the driver's attention can be alerted without affecting the behavior of the vehicle 100. it can.

  Further, since the predetermined value is specifically configured to be a value between 5 kgfcm and 15 kgfcm, or a value between 0.25 kgf and 0.755 kgf in the steering force of the driver, the vehicle 100 is similarly extended as described above. The driver's attention can be alerted without affecting the behavior of the driver.

  Further, since the steering torque is applied from the object 102 in the direction opposite to the direction avoided by the vehicle 100 before performing the contact avoidance assisting operation, the driver does not unintentionally move the steering wheel as described above. Thus, a reaction that generates a steering force in a direction opposite to the applied steering torque can be caused, and the subsequent avoidance steering can be made smoother.

  FIG. 7 is a flowchart showing the operation of the vehicle safety device according to the second embodiment of the present invention, more specifically, the contact avoidance support operation similar to that shown in FIG. .

  Explained below, after performing the same processing from S10 to S112 as S10 to S22 in the flowchart of FIG. 2 of the first embodiment, the process proceeds to S114, and whether or not the relative distance is less than the contact avoidance support distance + d. to decide. d is determined by relative speed × set time (for example, 0.5 sec to 1.0 sec).

  When the result in S114 is affirmative, the program proceeds to S116, and the steering torque is applied as in the first embodiment. Next, in S118, it is determined whether the relative distance is less than the contact avoidance support distance. The same applies when the result in S114 is negative.

  When the result in S118 is affirmative, the process proceeds to S120, and the contact avoidance support operation is executed as in the first embodiment. If the result in S106 or S118 is NO, the subsequent processing is skipped.

  In the vehicle travel safety device according to the second embodiment, the steering torque that precedes the distance d prior to the execution of the contact avoidance support operation is applied, so that the driver grips the steering wheel in a relaxed state. Even in such a case, it is possible to raise a driver's attention and to cause a reflex reaction to quickly steer in the avoidance direction, so that the start of the avoidance operation is not further delayed. The remaining configuration and effects are not different from those of the first embodiment.

  As described above, in the first and second embodiments, the object detection means (the imaging device 40, the radar device 42, the travel control unit 26, S10) that detects the object 102 present around the vehicle (own vehicle) 100 is provided. , S100), a movement state detection means (yaw rate sensor 50, travel control unit 26, S12, S102) for detecting the movement state of the vehicle, and contact with the detected object based on the detected movement state Contact possibility determination means (S14, S104) for determining the possibility of contact, and contact avoidance support for performing a contact avoidance support operation with the detected object when it is determined that there is a possibility of contact with the object In the vehicle travel safety device 10 including means (S16 to S24, S28, S106 to S114, S118, S120), before the contact avoidance support means performs the contact avoidance support operation. Was constructed from the object to comprise a steering torque applying means (S26, S116) for applying a predetermined time steering torque in a direction opposite the direction to avoid said vehicle.

  Further, the predetermined time is configured to be a time that does not affect the behavior of the vehicle and is perceivable by the driver.

  The predetermined time is configured to be between 50 msec and 100 msec.

  Further, an object detection means (an imaging device 40, a radar device 42, a travel control unit 26, S10, S100) for detecting an object existing around the vehicle (own vehicle) 100, and a motion state for detecting the motion state of the vehicle. Contact possibility determination means (S14, S104) for determining the possibility of contact between the detection means (yaw rate sensor 50, travel control unit 26, S12, S102) and the detected object based on the detected motion state. ) And contact avoidance support means (S16 to S24, S28, S106 to S114, S118, S120) for performing a contact avoidance support operation with the detected object when it is determined that there is a possibility of contact with the object. In the vehicle travel safety device 10 provided with a steering torque that applies a steering torque of a predetermined value or less before the contact avoidance support means performs the contact avoidance support operation. It was composed as comprising a click imparting means (S26, S116).

  The predetermined value is configured to correlate with a road surface reaction force during travel of the vehicle.

  The predetermined value is configured to be a value between 5 kgfcm and 15 kgfcm, or a value between 0.25 kgf and 0.75 kgf in the driver's steering force.

  Further, the steering torque applying means is configured to apply the steering torque in a direction opposite to the direction avoiding the vehicle from the object before the contact avoidance supporting means performs the contact avoidance assisting operation (S26, S116). did.

  In the above, the steering shaft is mechanically connected to the front wheels (drive wheels) via the rack and pinion mechanism, and the EPS actuator (electric motor) 22 is disposed on the rack to assist the steering. A steer-by-wire system in which the mechanical connection between the steering shaft and the front wheels is cut off may be used.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic diagram showing an overall traveling safety device for a vehicle according to a first embodiment of the present invention. It is a flowchart which shows the contact avoidance assistance operation | movement which is operation | movement of the apparatus shown in FIG. 2 is an explanatory diagram showing the positional relationship between the vehicle (own vehicle) and the object, explaining the contact possibility determination process of the flow chart. Similarly, it is explanatory drawing which shows the positional relationship of a vehicle (own vehicle) and an object explaining the calculation process of the target course of the flowchart of FIG. 2 is an explanatory time chart showing the application of steering torque in the flow chart. Similarly, it is an explanatory time chart showing the steering torque application of the flow chart of FIG. It is a flowchart which shows the contact avoidance assistance operation | movement similar to FIG. 2 by operation | movement of the driving safety device of the vehicle which concerns on 2nd Example of this invention.

Explanation of symbols

  DESCRIPTION OF SYMBOLS 10 Vehicle travel safety device, 16 control device, 20 brake actuator, 22 EPS actuator, 24 alarm device, 26 travel control unit, 34 brake control unit, 36 EPS control unit, 40 photographing device, 42 radar device, 44 steering torque sensor , 46 steering angle sensor, 50 yaw rate sensor, 52 vehicle speed sensor, 100 vehicle (own vehicle), 102 object (obstacle)

Claims (3)

  The possibility of contact with the detected object based on the detected motion state, the object detection means for detecting an object existing around the vehicle, the motion state detection means for detecting the motion state of the vehicle, and Driving safety of a vehicle comprising: a contact possibility determination unit for determining; and a contact avoidance support unit for performing a contact avoidance support operation with the detected object when it is determined that there is a possibility of contact with the object In the apparatus, the vehicle further includes a steering torque applying unit that applies a steering torque from the object in a direction opposite to a direction that the vehicle avoids before performing the contact avoidance support operation. Travel safety device.   2. The vehicle travel safety apparatus according to claim 1, wherein the predetermined time is a time that does not affect the behavior of the vehicle and is perceivable by a driver.   The vehicle travel safety device according to claim 1 or 2, wherein the predetermined time is a time between 50 msec and 100 msec.

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