JP2007331652A - Vehicle stopping device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To forcibly stop a vehicle in a place wherein the vehicle causes no obstruction to traffic of other vehicles when detecting lowering of consciousness of a driver. <P>SOLUTION: When lowering of consciousness (drowsing or the like) of the driver is detected during travel (S14: YES), front side road circumference conditions are detected to decide a target stop position (S18). The target stop position is decided based on presence/absence of a detected road end, presence/absence of an obstacle, presence/absence of a white line, road shoulder width, proper deceleration, and the like. Based on a lateral movement distance W necessary for stopping in the target stop position, a tire turning angle δis calculated (S22), and automatic operation is carried out to stop the vehicle in the target stop position by steering angle control and brake control (S22-S24). If steering is uncontrollable (S21: NO), a braking force difference is generated between the right and left wheels to change the direction of the vehicle to guide it to the target stop position. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to a vehicle stop device that executes stop control for stopping a running vehicle regardless of a vehicle operation state by a driver.

2. Description of the Related Art Conventionally, a vehicle stop device that forcibly stops a vehicle when a driver's consciousness is lowered and normal driving cannot be performed is known.
For example, in the snooze driving prevention device disclosed in Patent Document 1, the degree of consciousness reduction of the driver is detected from the running state of the vehicle, and the change state of the degree of consciousness reduction (occurrence period of consciousness reduction) is obtained. And if the occurrence period of consciousness decline is short, it is judged that it is due to fatigue or lack of sleep and the vehicle is forcibly stopped, and if the occurrence period of consciousness decline is long, it is judged that it is due to monotonous driving. Activate the alarm to alert the driver.
JP-A-6-107031

However, since the thing of patent document 1 does not judge the surrounding condition when stopping a vehicle compulsorily, it will stop at an improper place and will obstruct the passage of other vehicles.
An object of the present invention is to cope with the above problem, and is to forcibly stop the vehicle so as not to obstruct the passage of other vehicles.

  In order to achieve the above object, the present invention is characterized in that, in a vehicle stop device that executes stop control for stopping a running vehicle, regardless of a vehicle operation state by a driver, a front periphery of a road on which the vehicle runs Status detection means for detecting a situation, stop location determination means for determining a stop location of the vehicle based on the detection result obtained by the status detection means, and stop control so as to stop the vehicle at the determined stop location And stop control means for executing the above.

  According to the present invention having the above-described configuration, when the traveling vehicle is forcibly stopped, the situation detection means detects the situation in front of the road, and based on the detection result, the stop location determination means determines the stop location of the vehicle. Therefore, the vehicle can be stopped at a safe place that does not hinder the passage of other vehicles.

  Another feature of the present invention is provided with driving state determining means for determining whether or not the driver of the vehicle can normally drive, and the stop location determining means is configured such that the driver operates normally by the driving state determining means. When it is determined that the vehicle is in an incapable state, the vehicle stop location is determined based on the detection result obtained by the situation detection means.

  According to this invention, when the driver falls into a state in which the driver cannot drive normally while the vehicle is traveling, the vehicle can be forcibly stopped at an appropriate location based on the situation around the front of the vehicle.

Another feature of the present invention is that the stop location determination means detects the front shoulder of the road on which the vehicle is traveling based on the detection result obtained by the situation detection means, and detects the road shoulder on the detected road shoulder. The predetermined position is determined as a stop position of the vehicle.
In this case, the stop location determining means may determine a road shoulder position that can be stopped when a predetermined braking force is applied to the vehicle as the stop location.

  According to the present invention, since the vehicle is stopped on the shoulder of the road, it is possible to prevent a contact accident between the vehicles without interfering with the passage of other vehicles.

  Another feature of the present invention is that the stop control means determines the stop location based on a shoulder width between a road edge and a lane marker such as a white line.

  According to the present invention, since the stop location of the vehicle is determined based on the shoulder width, the vehicle can be stopped by selecting a location where the stop space is wide.

  Another feature of the present invention is that the stop control means controls the braking force so that the deceleration of the vehicle becomes the target deceleration, and the lateral movement distance necessary for the vehicle to travel to the stop location. The difference between the left and right wheels of the vehicle is calculated from at least three factors of the vehicle traveling speed and the target deceleration of the vehicle, and the calculated difference between the left and right wheel target braking forces is generated. It is to stop at the stop location.

  According to this, the stop control means calculates the braking force difference between the left and right wheels from at least three elements of the lateral movement distance of the vehicle, the traveling speed of the vehicle, and the target deceleration of the vehicle, and calculates the braking force difference between the left and right wheels. The vehicle can be decelerated toward a target stop location such as a road shoulder and stopped at the target stop location.

  Another feature of the present invention is that it includes at least three of a steering actuator that steers the wheel, a lateral movement distance required for the vehicle to travel to the stop position, a vehicle traveling speed, and a target deceleration of the vehicle. Steering control means for calculating the target turning angle of the wheel from the elements and drivingly controlling the turning actuator in accordance with the calculated target turning angle. The purpose is to control the braking force to achieve speed.

  According to this invention, the turning control means calculates the target turning angle of the wheel from at least three elements of the lateral movement distance of the vehicle, the traveling speed of the vehicle, and the target deceleration of the vehicle, and this target turning angle. Accordingly, the vehicle can be decelerated toward the target stop location such as the road shoulder and stopped at the target stop location by driving the steering actuator according to the above.

  Another feature of the present invention includes a steering inability determination unit that determines whether or not the steering control of the steering actuator is impossible, and when it is determined that the steering control of the steering actuator is impossible, The stop control means controls the braking force so that the deceleration of the vehicle becomes the target deceleration, and the lateral movement distance required for the vehicle to travel to the stop location, the vehicle traveling speed, and the vehicle target. The target braking force difference between the left and right wheels of the vehicle is calculated from at least three factors of deceleration, and the calculated target braking force difference between the left and right wheels is generated to stop the vehicle at the stop location.

  According to this invention, when it is determined by the steering impossible determination means that the steering control of the steering actuator is impossible, the direction of the vehicle is changed by the braking force difference control of the left and right wheels instead of the steering control. Accordingly, even when the steering actuator cannot be controlled, the vehicle can be decelerated toward the target stop location such as the road shoulder and stopped at the target stop location.

Hereinafter, a vehicle stop device according to an embodiment of the present invention will be described with reference to the drawings. FIG. 1 schematically shows a vehicle stop device 10 as one embodiment.
The vehicle stop device 10 of the present embodiment forcibly stops the vehicle in a safe place when the driver is unable to drive safely due to a decrease in consciousness due to falling asleep or the like. Unit 20, a vehicle surrounding state detection unit 30 that detects the situation around the front of the vehicle, a vehicle state detection unit 40 that detects the state of the vehicle, a consciousness decrease detection unit 20, a vehicle surrounding state detection unit 30, and a vehicle state detection An electronic control unit 50 (hereinafter referred to as a main ECU 50) that determines the stop location of the vehicle and calculates a vehicle control amount based on each detection result of the unit 40, and an alarm unit 60 that notifies the surrounding vehicle and pedestrian of the danger. And a vehicle state control unit 70 for stopping the vehicle at an appropriate place.

  In this embodiment, the consciousness lowering detection unit 20 performs various image processing on a camera 21 that is provided in front of the driver's seat and images a driver's face position, and an image signal output from the camera 21. It comprises an image processing device 22 (hereinafter referred to as an image ECU 22). The image ECU 22 includes a microcomputer as a main part, converts the image signal output from the camera 21 into an image signal that can specify the position and orientation of the driver's face, and the state of the eyes. Reference data such as a face outline and an eye outline when facing the front is compared with actual detected image data. And, when the driver's face does not exist in the detected image, the face is not facing the front, the eyes are closed, and the like are continuously detected for a predetermined period, the driver cannot drive normally. It judges that it is in a state and outputs a consciousness reduction signal to the main ECU 50.

Note that the consciousness decrease detection unit 20 is not limited to the configuration in which the state of the driver is determined based on the image. You may decide that you are in a state where you cannot.
Alternatively, the driver's heart rate and respiratory rate may be detected, and the driver's arousal level may be determined based on these two detection values. The heart rate can be detected by an ultrasonic sensor built in the driver's seat, and the respiration rate can be detected by measuring the chest movement using a pressure sensor or the like incorporated in the seat belt. Then, it may be determined that the driver is dozing when the ratio between the heart rate and the respiratory rate is out of the reference range.

  In the present embodiment, the vehicle surrounding state detection unit 30 is a stereo camera 31 that captures the front periphery of the host vehicle, and an image processing device that performs various types of image processing on the image signal output from the stereo camera 31. 32 (hereinafter referred to as an image ECU 32) and a radar sensor 33 that detects an obstacle existing around the front of the host vehicle.

The stereo camera 31 is a compound-eye camera in which two cameras 31a and 31b are arranged on the left and right. The stereo camera 31 has lenses with the same focal length and parallel optical axes, and images road conditions from two viewpoints using these two lenses. To do. The image ECU 32 includes a microcomputer as a main part, and inputs a pair of left and right image signals obtained by imaging with the stereo camera 31, and performs image processing (edge extraction processing, etc.) on each image signal. To extract feature points, and detect the position of a lane marker (hereinafter simply referred to as a white line) such as an edge of a road ahead or a white line, an obstacle existing in the front, and the like. In this case, the corresponding points p1 (x1, y1) and p2 (x2, y2) on the left and right images captured by the stereo camera 31 are collated, and based on the correlation, the object to be imaged is obtained by triangulation. Three-dimensional distance data (x, y, z) is generated. Therefore, it is possible to estimate the road edge, the position of the white line, and the position of the obstacle with respect to the host vehicle.
The road edge is the boundary of the road, and includes the steps between the roadway and the sidewalk, blocks, gutters, curbs, grasslands, etc.

The radar sensor 33 is configured by a radar device using millimeter waves or infrared rays, and outputs a signal according to the distance to an obstacle ahead of the vehicle and present in the horizontal direction of the vehicle to the main ECU 50. This radar apparatus is assembled at the front end of a vehicle (for example, near the front grille), and includes a radar antenna that can rotate around a rotation axis extending in the vertical direction. The radar antenna is an antenna having directivity, and rotates within a predetermined angle range around the rotation axis based on an instruction from the main ECU 50 to transmit millimeter waves and infrared rays, and within the predetermined angle range. It is configured to receive millimeter waves and infrared rays reflected by the existing preceding vehicle.
As a result, the radar sensor 33 responds to the distance from an obstacle existing within a predetermined angle range by the radar antenna transmitting millimeter waves and infrared rays and receiving the reflected millimeter waves and infrared rays. The signal is output to the main ECU 50 as a signal.

  The vehicle state detection unit 40 includes a vehicle speed sensor 41 that outputs a pulse signal at a cycle according to the traveling speed of the host vehicle, and a steered wheel (in this embodiment, the front wheel is a front wheel but other types such as a front and rear wheel steered type). And a steering angle sensor 42 for detecting a steering angle of (good).

  The main ECU 50 includes a microcomputer having a CPU, RAM, ROM, various interfaces and the like as a main part, and executes a vehicle stop control routine described later.

  The warning unit 60 urges the surrounding vehicles and pedestrians to be alerted when the vehicle is forcibly stopped by a vehicle stop control process described later. In this embodiment, the hazard lamp 61 and the horn 62 are used. Is used.

  The vehicle state control unit 70 includes an electric control brake device 71 including a brake actuator 73 and a brake ECU 72 that drives and controls the brake actuator 73, and a steering ECU 75 that drives and controls the steering actuator 76 and the steering actuator 76. And a control-type steering device 74.

The brake actuator 73 includes an electromagnetic solenoid valve, a reservoir, a pressure pump, and the like (hereinafter not shown) in a hydraulic circuit between the master cylinder and the wheel cylinder of each wheel. Accordingly, the hydraulic pressure of the master cylinder corresponding to the wheel acts on the wheel cylinder of each wheel, and at the time of forced stop, the hydraulic pressure is switched and the hydraulic pressure pressurized by the pump is applied to each wheel cylinder.
The brake ECU 72 controls the electromagnetic solenoid to switch the hydraulic circuit of the brake actuator 73 when performing vehicle stop control, which will be described later, and applies the hydraulic pressure pressurized by the pump to the wheel cylinder to apply a braking force to the wheels. . In this case, the pressure acting on the wheel cylinder for each wheel is detected by a pressure sensor (not shown), and the braking force is controlled by adjusting the hydraulic pressure.

The electric control type steering device 74 uses an electric power steering device in the present embodiment. Since this electric power steering device is general, it will not be described with reference to the drawings, but a type in which an electric motor is incorporated in the steering shaft that connects the steering handle and the rack bar to give steering torque to the steering shaft, Various types such as a type in which an electric motor is incorporated in the rack bar and the rack bar is driven in the vehicle width direction to apply a turning torque can be employed.
The electric power steering apparatus includes an assist controller that controls driving of the electric motor, calculates a necessary assist torque based on a vehicle speed signal from the vehicle speed sensor and a steering torque signal from the steering torque sensor, and obtains the necessary assist torque. As a result, the steering operation of the driver is assisted by controlling the energization of the electric motor.

In the present embodiment, the electric power steering device is used to perform the steering control for interrupting the normal assist torque control when the vehicle is forcibly stopped and laterally moving the vehicle to the target stop position. .
Therefore, the steering actuator 76 in this embodiment is an electric motor of an electric power steering device, and the steering ECU 75 is an assist controller.

Next, a vehicle stop control process for detecting a driver's consciousness drop and forcibly stopping the vehicle will be described. FIG. 2 represents a vehicle stop control routine executed by the main ECU 50 and is stored as a control program in the ROM of the main ECU 50.
This vehicle stop control routine is started by turning on an ignition switch (not shown), and is repeatedly executed at a predetermined short cycle. In parallel with this control routine, the driver's driving state monitoring by the consciousness decrease detection unit 20 and the vehicle front state detection by the vehicle surrounding state detection unit 30 are performed.

When this control routine is activated, first, in step S11, vehicle speed information from the vehicle speed sensor 41 is input to determine whether the current vehicle speed Vx is greater than 0, that is, whether or not the vehicle is traveling.
If the vehicle is not running, stop control of the vehicle is unnecessary, so the control routine is temporarily exited. At this time, the state of the flag F is confirmed (S12). This flag F is set to F = 0 when the control routine is started, and is set to F = 1 when brake braking is being performed. Accordingly, when this control routine is activated and the vehicle is not traveling, F = 0, so that “NO” is determined in the step S12 and the present control routine is exited as it is.

If this control routine is repeated at a predetermined short cycle and it is determined that the vehicle has traveled (S11: YES), then a detection signal from the consciousness lowering detection unit 20 is input (S13).
In parallel with the vehicle stop control routine, the consciousness decrease detection unit 20 constantly detects the state of the driver and outputs the detection result to the main ECU 50. For example, the image ECU 22 determines based on the image captured by the camera 21 whether or not the driver is closing his eyes or the driver is not facing the front, and such a disabled state continues for a predetermined time. When this is done, a “consciousness-reduced state” signal is output to the main ECU 50. Therefore, it is possible to capture a situation in which the driver cannot drive normally due to the driver falling asleep or sudden changes in physical condition such as myocardial infarction.

  Subsequently, in step S14, it is determined whether or not the output of the consciousness decrease detection unit 20 is “there is a consciousness decrease state”. If the driver's consciousness decrease state (safe driving impossible state) is not detected, this control routine is executed. Once out, the state of the flag F is confirmed at this time (S15). In this case, since brake braking is not started and F = 0, the present control routine is exited as it is.

If the driver's consciousness lowering state continues for a predetermined time and the “consciousness lowering state present” signal is output from the consciousness lowering detection unit 20 while such processing is repeated, the determination in step S14 becomes “YES”. The process proceeds to step S16.
In this step S16, the hazard lamp 61 of the alarm unit 60 is blinked and the horn 62 is sounded to notify the surrounding vehicles and pedestrians of a dangerous state.

Subsequently, in step S <b> 17, the main ECU 50 inputs a surrounding state detection signal in front of the vehicle from the vehicle surrounding state detection unit 30. Here, the shape of the road, the state of white lines formed on the road, obstacles existing on the road, and the like are detected.
In parallel with the vehicle stop control routine, the vehicle surrounding situation detection unit 30 constantly detects the surrounding situation in front of the vehicle and outputs the detection result to the main ECU 50. For example, the image ECU 32 processes image signals obtained by the stereo camera 31 to extract road edges and white lines, and generates three-dimensional distance data to recognize distance relations at these points. The detection of the road edge is performed by extracting feature points such as steps between the roadway and the sidewalk, blocks, gutters, curbs, and grass. At the same time, the image ECU 32 also extracts obstacles present on the road, and outputs obstacle position information to the main ECU 50 together with the three-dimensional distance data of the road.
The main ECU 50 increases the detection accuracy by detecting not only the detection signal from the image ECU 32 but also the detection signal from the radar sensor 33 in detecting the obstacle.

Subsequently, in step S18, the main ECU 50 performs processing for determining a vehicle stop position. This process is performed according to the flowchart shown in FIG.
First, in step S18a, a braking distance range (L1 to L2) when braking is performed within a preset appropriate deceleration range (minimum appropriate deceleration G1 to maximum appropriate deceleration G2) is calculated. For example, considering the case where the current vehicle speed Vx detected by the vehicle speed sensor 41 is read and a constant deceleration motion is performed from the vehicle speed Vx, the braking distances L1 and L2 can be calculated as in the following equations (1) and (2). .

FIG. 4 shows a braking distance range (L1 to L2) when a braking force in the appropriate deceleration range is applied to the vehicle C.
Subsequently, in step S18b, it is determined whether or not an end ER of the road ahead from the vehicle C by a braking distance range (L1 to L2) can be detected. That is, it is determined whether or not the end portion ER of the road in the range (L1 to L2) in which the vehicle C is to be stopped can be detected from the image data of the road ahead by the vehicle surrounding state detection unit 30.
When the contour of the road has not been extracted by the image ECU 32, the determination in step S18b is “NO”, and the position when braking is performed with the optimum deceleration Gbest without changing the traveling direction is set as the target stop position ( S18c).

  On the other hand, if it is determined in step S18b that the road edge ER has been detected, then in step S18d, whether there is an obstacle in the braking distance range (L1 to L2) and in the path to it. Determine whether. This determination is performed using not only the obstacle presence determination by the image ECU 32 but also a signal from the radar sensor 33. In this case, it is not required that the obstacle does not exist over the entire braking distance range (L1 to L2). For example, when the obstacle is in the rear part within the braking distance range (L1 to L2), the front part within the braking distance range is the vehicle stoppable area, so it is determined that there is no obstacle.

If it is determined in step S18d that “there is an obstacle”, the stop position when the vehicle is braked at the optimum deceleration Gbest without changing the traveling direction is set as the target stop position (S18c).
On the other hand, if it is determined in step S18d that there is no obstacle, then in step S18e, a white line WL representing the road lane edge is formed on the road within the braking distance range (L1 to L2). Determine whether or not.
When the white line WL is formed, the road shoulder position where the road shoulder width is maximum within the braking distance range (L1 to L2) is set as the target stop position (S18f). That is, a place where the width of the shoulder SR between the white line WL and the road edge ER is maximized is selected, and the road shoulder position is set as the target stop position. The size of the shoulder width is calculated from the three-dimensional distance data from the vehicle surrounding state detection unit 30.

On the other hand, if it is determined in step S18e that the white line WL is not formed, the road shoulder position that stops when braking is performed at the optimum deceleration Gbest is set as the target stop position (S18g). The optimum deceleration Gbest is an optimum value in the appropriate deceleration range (minimum appropriate deceleration G1 to maximum appropriate deceleration G2) and is set in advance.
In addition, when the vehicle stoppable range is limited by an obstacle or the like (for example, when the obstacle is in the rear portion within the braking distance range (L1 to L2)), the optimal reduction in the limited range is performed. Speed is selected.
In step S18f, if the road shoulder width is uniform within the braking distance range (L1 to L2), the road shoulder position that stops when braking is performed at the optimum deceleration Gbest is set as the target stop position.

また、ステップＳ１８ｅにおいて白線ＷＬが検出されない場合は、予め設定された最適減速度Ｇbestが目標減速度Ｇ＊として設定される。但し、車両停止可能範囲が、障害物等により制限され最適減速度Ｇbestに設定できない場合には、その制限された範囲に停止することが可能な最適減速度Ｇbestに最も近い値が目標減速度Ｇ＊として設定される。
また、ステップＳ１８ｂにおいて道路端ＥＲが検出できなかった場合、および、ステップＳ１８ｄにおいて障害物の存在を検出した場合には、予め設定された最適減速度Ｇbestが目標減速度Ｇ＊として設定される。 When the target stop position of the vehicle is determined in this manner, the process proceeds to step S19, and a target deceleration G * for stopping at the target stop position is set. For example, in step S18f, when the maximum shoulder width position is set as the target stop position, the target deceleration G * is expressed by the following equation (3) in consideration of the case where the distance Lx to the target stop position is subjected to equal deceleration motion. It can be calculated as follows.

If the white line WL is not detected in step S18e, the preset optimum deceleration Gbest is set as the target deceleration G *. However, when the vehicle stoppable range is limited by an obstacle or the like and cannot be set to the optimum deceleration Gbest, the value closest to the optimum deceleration Gbest that can stop within the restricted range is the target deceleration Gbest. Set as *.
Further, when the road edge ER cannot be detected in step S18b, and when the presence of an obstacle is detected in step S18d, a preset optimum deceleration Gbest is set as the target deceleration G *.

  Next, in step S20, a lateral movement distance W required until the vehicle is stopped at the target stop position is calculated. That is, as shown in FIG. 4, the lateral deviation between the position (indicated by a broken line) and the target stop position (indicated by a solid line) when the vehicle C travels in the current traveling direction by a braking distance Lx and stops. The amount is calculated as the lateral movement distance W. The lateral movement distance W is calculated from the three-dimensional distance data from the vehicle surrounding state detection unit 30.

ここで、Ａはホイールベース、Ｇ＊は目標減速度、Ｖｘは車速、Ｗは横移動距離である。 In order to stop the vehicle at the target stop position on the shoulder, it is necessary to change the traveling direction of the vehicle. Therefore, in the present embodiment, the following processing is performed.
First, in step S21, it is determined whether or not the steering angle control is possible. This control routine is repeatedly executed in a short cycle, but since it is not known at the first time whether or not the steering control is possible, the initial value is set to “steering control is possible”.
If it is determined that the steering control is possible, in step S22, the tire turning angle δ is calculated as in the following equation (4) in order to drive the vehicle toward the target stop position. This tire turning angle δ (radian) represents a steering angle that is changed based on the steering angle of the current steered wheel.

Here, A is the wheel base, G * is the target deceleration, Vx is the vehicle speed, and W is the lateral movement distance.

  Subsequently, in step S23, the main ECU 50 outputs a steering control command for instructing the tire turning angle δ to the steering ECU 75. The turning ECU 75 determines a turning angle by inputting a detection signal of a rotation angle sensor (not shown) that detects the rotation angle of an electric motor as the turning actuator 76, and the turning angle is commanded from the main ECU 50. The rotation angle of the electric motor is controlled so that the tire cut angle δ is obtained. Instead of the rotation angle signal of the electric motor, the detection signal of the steering angle sensor 42 may be input to the steering ECU 75 to perform the steering control.

Next, in step S24, a forced brake control command for commanding the target deceleration G * is output to the brake ECU 72. The brake ECU 72 inputs a vehicle speed signal detected by the vehicle speed sensor 41 via the main ECU 50, calculates an actual vehicle deceleration based on a temporal change in the vehicle speed Vx obtained from the vehicle speed signal, The hydraulic pressure of the brake actuator 73 is controlled so that the deceleration becomes the target deceleration G *.
Since this control routine is repeatedly executed at a predetermined short cycle, in detecting the deceleration of the vehicle, the vehicle speed V old immediately before or the predetermined control cycle and the vehicle speed V detected this time are detected.
It can be calculated by determining the amount of change over time with new. In addition, you may make it detect by providing the acceleration sensor which detects the acceleration of the front-back direction of a vehicle.

When the brake control is thus started, next, the process proceeds to step S25, the flag F is set to F = 1, and this control routine is temporarily exited.
This control routine is repeatedly executed, and if the driver is in a state of reduced consciousness, the steering angle control and the brake control are continued toward the target stop position by the above-described processing.
In this case, there is a case where the steering handle is strongly gripped by the driver and cannot be steered by the steering actuator 76. That is, in step S23, even if the steering ECU 75 controls the steering actuator 76 to be energized, the target turning angle may not be obtained. In order to cope with such a case, the main ECU 50 determines that “steering control is impossible” in step S21 when an appropriate response of the detected turning angle to the steering control command cannot be continuously obtained for a reference time or longer. Instead of the turning control, the process of step S26 is performed.

ここで、Ｉは慣性モーメント、Ｇ＊は目標減速度、Ｖｘは車速、Ｔはトレッド、Ｗは横移動距離である。 In step S26, a braking force difference f between the left and right wheels is calculated. That is, the braking force difference f between the left and right wheels is calculated in order to generate a yaw moment in the vehicle body and cause the vehicle to decelerate toward the target stop position.
This left-right braking force difference f is calculated as in the following equation (5).

Here, I is the moment of inertia, G * is the target deceleration, Vx is the vehicle speed, T is the tread, and W is the lateral movement distance.

  Subsequently, in step S27, the hydraulic pressure of the left and right wheel brake actuators 73 is controlled so as to obtain the target deceleration G * while generating the left / right braking force difference f. Since the braking force difference f between the left and right wheels is proportional to the pressure difference (ΔP = Pl−Pr) between the brake hydraulic pressures (Pl, Pr) of the left and right wheels, the pressure difference ΔP is obtained from the braking force difference f obtained by the equation (5). By controlling according to this, a predetermined yaw moment can be generated in the vehicle body to obtain the lateral movement amount.

By repeating such processing, the main ECU 50 always selects the target stop position while confirming the road surrounding conditions, and automatically steers the vehicle toward the target stop position. If the driver's consciousness is restored during the execution of the forced brake control of the vehicle, the determination in step S14 is “NO”, the forced brake control (S16 to S26) is stopped, and the step The process proceeds to the flag determination process in S15.
In step S15, it is determined whether or not the flag F is set to “1”. In this case, since the flag F is set to F = 1, the determination is “YES”, the flag F is reset to F = 1 in step S27, and this control routine is temporarily exited.

On the other hand, when the vehicle is stopped by the forced brake control without recovering the driver's consciousness (vehicle speed Vx = 0), the determination in step S11 is “NO”, and the process proceeds to the flag determination process in step S12.
In this step S12, it is determined whether or not the flag F is set to “1”. In this case, since the flag F is set to F = 1, the determination is “YES”, and then the state of the driver is detected in step S28. That is, the detection signal from the consciousness decrease detection unit 20 is read.

Next, in step S29, it is determined whether or not a “no consciousness reduction state” signal is output from the consciousness reduction detection unit 20, that is, whether or not the driver's consciousness has been recovered. When the detection signal of the consciousness lowering detection unit 20 is “the state of consciousness is lower” (S29: NO), the brake braking is held (S30) and the operation of the alarm unit 60 is continued (S31). Exit once.
On the other hand, when the detection signal of the consciousness decrease detection unit 20 is “no consciousness decrease state” (S29: YES), the flag F is set to F = 0 in step S32, and this control routine is temporarily exited.
That is, the processes in steps S28 to S32 hold the brake braking and the alarm operation until the driver's consciousness is restored when the vehicle is stopped by the forced brake control.

  And after a driver | operator's consciousness is recovered | restored, brake braking and an alarm action are cancelled | released and it waits for the driving | running | working start of a vehicle again. When vehicle travel is thus started, as described above, the driver's consciousness lowered state is constantly monitored, and the vehicle is forcibly stopped based on the driver's consciousness lowered state.

According to the vehicle stop device of the present embodiment described above, when the driver's state is constantly monitored by the consciousness decrease detection unit 20 while the vehicle is running, and it is determined that the driver cannot drive normally, the vehicle Can be forcibly stopped.
In addition, when the vehicle is forcibly stopped, the road shoulder is selected as a stop location based on the road situation detected by the vehicle surrounding situation detection unit 30, and in particular, the position where the road shoulder width is maximum is selected as the target stop position. It is possible to prevent contact accidents between vehicles without disturbing the passage of other vehicles.

  Further, when the forced stop control is performed, the alarm unit 60 is activated, so that not only the surrounding vehicle or pedestrian can be informed of a dangerous state, but also the driver himself is alerted. be able to. Moreover, when the driver's consciousness does not recover even after the vehicle stops, to continue the brake braking and alarm operation, for example, even when the driver is unconscious due to myocardial infarction, etc. Inform the surrounding people of the situation and rescue them quickly.

  Even in cases where the driver has squeezed the steering wheel when performing forced stop control and the steering angle control of the wheels is not possible, the direction of the vehicle is adjusted using the braking force difference between the left and right wheels. Since the vehicle is changed, the vehicle can be stopped at the target stop location.

  Although the vehicle stop device 10 of the present embodiment has been described above, the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the object of the present invention.

  For example, in order to improve the accuracy of the vehicle surrounding state detection unit 30, a navigation system 34 may be used as shown by a broken line in FIG. For example, road shape data including road shoulder width data may be stored in the map database 35 of the navigation system 34, and the position of the vehicle on the road may be grasped by a GPS signal to assist the selection of the target stop position.

Moreover, in this embodiment, although the electric power steering apparatus is utilized as a steering control apparatus, you may use other steering control apparatuses, such as a steering by wire system. The steering-by-wire system allows the steered wheels to be steered independently of the steering wheel, even when the driver is gripping the steering wheel when consciousness declines. There is no need to switch to.
Further, the direction of the vehicle may be changed only by the difference between the left and right braking forces without using the steering control device.

  Note that the vehicle surrounding state detection unit 30 of the present embodiment corresponds to the state detection means of the present invention, and the processing of step S18 in the vehicle stop control routine executed by the main ECU 50 of the present embodiment is the stop location determination means of the present invention. Equivalent to. Further, the processing of steps S22, S23, S24, and S26 in the vehicle stop control routine executed by the vehicle state control unit 70 and the main ECU 50 in the present embodiment corresponds to the stop control means of the present invention, and step S21 in the vehicle stop control routine. This processing corresponds to the steering impossible determination means of the present invention. Moreover, the consciousness reduction detection part 20 of this embodiment is equivalent to the driving | running state judgment means of this invention.

1 is a system configuration diagram of a vehicle stop device according to an embodiment of the present invention. It is a flowchart showing the vehicle stop control routine which main ECU of this embodiment performs. It is a flowchart showing the target stop position selection routine in a vehicle stop control routine. It is explanatory drawing explaining the braking distance range (L1-L2) and the lateral movement distance W. FIG.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 ... Vehicle stop apparatus, 20 ... Consciousness fall detection part, 21 ... Camera, 22 ... Image ECU, 30 ... Vehicle surrounding condition detection part, 31 ... Stereo camera, 32 ... Image ECU, 33 ... Radar sensor, 40 ... Vehicle state detection , 41 ... Vehicle speed sensor, 42 ... Rudder angle sensor, 50 ... Main ECU, 60 ... Alarm unit, 61 ... Hazard lamp, 62 ... Horn, 70 ... Vehicle state control unit, 71 ... Electrically controlled brake device, 72 ... Brake ECU, 73 ... brake actuator, 74 ... electrically controlled steering device, 75 ... steering ECU, 76 ... steering actuator, SR ... road shoulder, ER ... road end, WL ... white line.

Claims (8)

In a vehicle stop device that executes stop control to stop a running vehicle regardless of the vehicle operation state by the driver,
A situation detection means for detecting the situation in front of the road on which the vehicle is traveling;
Based on the detection result obtained by the situation detection means, stop location determination means for determining the stop location of the vehicle,
A vehicle stop device comprising stop control means for executing stop control so as to stop the vehicle at the determined stop location. A driving state judging means for judging whether or not the driver of the vehicle can drive normally;
The stop location determination means determines the stop location of the vehicle based on the detection result obtained by the situation detection means when the driving state determination means determines that the driver is in a state in which the driver cannot normally operate. The vehicle stop device according to claim 1.   The stop location determination means detects the front shoulder of the road on which the vehicle is traveling based on the detection result obtained by the situation detection means, and sets the predetermined position on the detected road shoulder as the stop location of the vehicle. 3. The vehicle stop device according to claim 1, wherein the vehicle stop device is determined.   4. The vehicle stop device according to claim 3, wherein the stop location determining means determines, as the stop location, a road shoulder position that can be stopped when a predetermined braking force is applied to the vehicle.   5. The vehicle stop device according to claim 3, wherein the stop location determining means determines the stop location based on a shoulder width between a road edge and a lane marker such as a white line.   The stop control means controls the braking force so that the deceleration of the vehicle becomes the target deceleration, the lateral movement distance necessary for the vehicle to travel to the stop location, the traveling speed of the vehicle, the vehicle The target braking force difference between the left and right wheels of the vehicle is calculated from at least three factors of the target deceleration of the vehicle, and the vehicle is stopped at the stop position by generating the calculated target braking force difference between the left and right wheels. The vehicle stop device according to any one of claims 1 to 5, characterized in that: A steering actuator that steers the wheels;
The target turning angle of the wheel is calculated from at least three elements of the lateral movement distance required for the vehicle to travel to the stop location, the traveling speed of the vehicle, and the target deceleration of the vehicle. Steering control means for driving and controlling the steering actuator according to a target steering angle,
The vehicle stop device according to any one of claims 1 to 5, wherein the stop control means controls a braking force so that a deceleration of the vehicle becomes a target deceleration. A steering impossible judgment means for judging whether or not the steering control of the steering actuator is impossible;
When it is determined that the steering control of the steering actuator is impossible, the stop control means controls the braking force so that the deceleration of the vehicle becomes the target deceleration, and the vehicle reaches the stop location. The target braking force difference between the left and right wheels of the vehicle is calculated from at least three factors of the lateral movement distance required for traveling, the vehicle traveling speed, and the target deceleration of the vehicle. The vehicle stop device according to claim 7, wherein the vehicle is stopped at the stop position by generating a target braking force difference.

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