WO2017195807A1

WO2017195807A1 - Driver abnormality occurrence detector and safety device using same

Info

Publication number: WO2017195807A1
Application number: PCT/JP2017/017628
Authority: WO
Inventors: 勇大森
Original assignee: 勇大森
Priority date: 2016-05-10
Filing date: 2017-05-10
Publication date: 2017-11-16
Also published as: JP5997410B1; JP2017202816A

Abstract

Provided is a driver abnormality occurrence detector capable of more accurately detecting occurrence of an abnormality when the condition becomes serious after a posture change first occurs. The driver abnormality occurrence detector according to the present invention is characterized by comprising: a posture change sensor that detects a posture change of a driver; a confirmation unit that, in a case where the detected posture change is a posture change that is assumed in advance to occur when there is an abnormality and the amount of the change exceeds a predetermined range, requests the driver to confirm whether or not there is an abnormality, and outputs an abnormality occurrence detection signal if no response is received; and a special monitoring mode control unit that, in a case where a response to the confirmation request is received from the driver to indicate that there is no abnormality, sets a range narrower than the predetermined range until a predetermined time has elapsed, and causes the confirmation unit to request the driver to confirm whether or not there is an abnormality when the narrower range is exceeded. This configuration enhances the accuracy of detecting occurrence of a driver abnormality so that the life of not only the driver but also of surrounding pedestrians can be saved.

Description

Driver abnormality occurrence detector and safety device using the same

[Technical Field] The present invention relates to a driver abnormality occurrence detector for detecting a state of a driver's physical condition, falling asleep, heart failure, etc. in a vehicle such as an automobile, and a safety device using the same.

In order to detect poor physical condition of the driver, a detector of a type that monitors the driving posture (Patent Document 1) and a detector that monitors a temperature rise of the face to detect a drowsiness (Patent Document 2) are provided. Safety devices are known.

JP 2011-57134 A JP 2008-102777 A

People rarely fall into a serious state in a short time of 1 to 2 minutes after they start to feel sick or feel drowsy. More specifically, it often leads to a state in which the user cannot drive, loses his mind, falls asleep, and the like. However, in the conventional detector, even if the first change occurs, the processing is continued without changing the detection sensitivity. Considering prevention of erroneous detection, the sensitivity is often set to a medium or low sensitivity, and there is a possibility that the occurrence of the serious situation cannot be detected.

The present invention has been made to solve the above-described problems of the conventional example, and a driver abnormality occurrence that can more accurately detect an abnormality occurrence when a serious state occurs after the first posture change has occurred. An object is to provide a detector and a safety device using the same.

In order to achieve the above object, the present invention provides a driver abnormality occurrence detector that detects that an abnormality has occurred in a driver during driving of a vehicle, a posture change sensor that detects a posture change of the driver, and the detection The posture change at the time of occurrence of an abnormality assumed in advance is an attitude change at the time of occurrence of an abnormality, and when the amount of change exceeds a predetermined range, the driver is asked to confirm whether or not an abnormality has occurred, When there is no response, when there is a confirmation unit that outputs an abnormality detection signal and a response indicating that no abnormality has occurred from the driver in response to the confirmation request, until the predetermined time T1 elapses, A special monitoring mode control unit that determines a narrower range than the determined range and causes the confirmation unit to confirm whether or not an abnormality has occurred when the narrow range is exceeded. It is characterized by .

The driver abnormality occurrence detector includes an electrocardiogram waveform sensor for detecting a driver's electrocardiogram waveform, and the special monitoring mode control unit monitors the electrocardiogram waveform obtained by the electrocardiogram waveform sensor to detect arrhythmia, ventricular fibrillation or atrium. When fibrillation is detected, it is preferable that the confirmation unit causes the driver to confirm whether or not an abnormality has occurred.

The driver abnormality occurrence detector includes an electrocardiogram waveform sensor for detecting an electrocardiogram waveform of the driver, and the special monitoring mode control unit monitors the electrocardiogram waveform obtained by the electrocardiogram waveform sensor, and the driver's demand type pacemaker When it is detected that it is operating, it is preferable that the confirmation unit causes the driver to confirm whether or not an abnormality has occurred.

In the driver abnormality occurrence detector, the predetermined time T1 is preferably 40 minutes.

The safety device of the present invention is a safety device that decelerates the vehicle and stops movement when an abnormality occurrence detection signal is output by any one of the driver abnormality occurrence detectors and the confirmation unit of the driver abnormality occurrence detector. And a securing portion.

The safety device includes an obstacle sensor that detects an obstacle ahead of the vehicle, and the safety ensuring unit collides with the obstacle when the obstacle is detected ahead by the obstacle sensor. It is preferred to stop the vehicle before the emergency stop.

According to the present invention, among the changes in the driver's posture, the posture change at the time of occurrence of an abnormality is detected in advance, and when the amount of change exceeds a predetermined range, the driver is confirmed and an abnormality occurs. If there is a response indicating that there is no response, the special monitoring mode is set so that the range for determining the occurrence of abnormality is narrow, that is, high sensitivity until the predetermined time T1 elapses. By adopting this configuration, under a situation where there is little suspicion of occurrence of an abnormality, it is possible to prevent a false occurrence of an abnormality while preventing an operation that is performed during normal operation from being erroneously detected by monitoring relatively loosely. In a situation where there is a possibility, the detection accuracy of occurrence of abnormality can be increased by setting the sensitivity to be high.

The block block diagram of the motor vehicle provided with the safety device provided with the driver abnormality generation detector which concerns on one embodiment of this invention. Functional block diagram of a safety device. The partial side view of the motor vehicle which shows arrangement | positioning of a sensor. The partial top view of the motor vehicle which shows arrangement | positioning of a sensor. The flowchart which shows the main routine of the process performed in a safety device. The figure which shows the attitude | position change judged to be abnormal, and the attitude | position change which is not judged abnormal. A confirmation screen displayed on the touch panel display when an alert is activated. The figure explaining the abnormality content which can be understood from an electrocardiogram waveform. The figure explaining the difference by the presence or absence of the special monitoring mode setting of the range judged to be abnormal. The flowchart of a safety ensuring process.

The driver abnormality occurrence detector according to the present invention confirms whether or not an abnormality has occurred and a detection unit that detects a posture change at the time of occurrence of an abnormality in the driver's posture during driving of the vehicle. When there is an abnormality, a confirmation unit that outputs an abnormality occurrence signal and when there is a response indicating that no abnormality has occurred, it is determined that an abnormality has occurred as a special monitoring mode until a predetermined time T1 elapses. And a special monitoring mode control unit that sets the range to be narrowed, that is, high sensitivity. The detection unit eliminates posture changes when operating the car navigation system, posture changes when lighting the cigarettes, posture changes caused by the interaction in the conversation, etc. Then, a change in posture that leans forward or a change in posture that moves backward is detected as a change in posture due to the occurrence of an abnormality. By adopting this configuration, under a situation where there is little suspicion of occurrence of an abnormality, it is possible to prevent a false occurrence of an abnormality while preventing an operation that is performed during normal operation from being erroneously detected by monitoring relatively loosely. In a situation where there is a possibility, the detection accuracy of occurrence of abnormality can be increased by setting the sensitivity to be high.

The driver abnormality occurrence detector having a preferable configuration includes an electrocardiogram waveform sensor and is detected based on the electrocardiogram waveform (a) occurrence of arrhythmia, ventricular fibrillation or atrial fibrillation, (b) driver demand type When the pacemaker is activated, that is, when the natural pulse is stopped and the pacemaker has started the paging operation, the confirmation unit is made to confirm whether or not an abnormality has occurred. By adopting this configuration, the abnormality detection capability of the driver abnormality occurrence detector can be enhanced.

An automobile 100 will be described as an example of a vehicle including a driver abnormality occurrence detector 1 according to an embodiment of the present invention and a safety device 50 including the detector 1.

As shown in FIG. 1, the automobile 100 includes a safety device 50 and other parts 70 including an engine, a brake pedal, a steering wheel, and the like. The safety device 50 includes a central processing unit CPU 51, a ROM 52 that records control programs and system programs, a RAM 53 that is used as a work area, a brake control unit 54, a hazard lamp 55, and a display monitor 56. ing. The brake control unit 54 operates in accordance with a stop command from the CPU 51 and works to decelerate the vehicle speed. The hazard lamp 55 blinks in response to a lighting command from the CPU 51. The display monitor 56 incorporates a touch panel type pointing device and a speaker, and is provided at a position that can be operated by a driver on the front portion of the automobile 100.

Furthermore, the safety device 50 controls the other components 70 (for example, accelerator adjustment), decelerates to stop the movement, and further stops the engine, and further includes an engine control unit 57 having a function of stopping the engine, a head longitudinal movement sensor 58, The head movement sensor 59, an electrocardiogram waveform sensor 60, and an obstacle sensor 61 are provided. The head back-and-forth motion sensor 58 detects the amount of forward and backward movement of the driver's head in the driver's seat. The left-right movement sensor 59 detects the left-right movement direction and movement amount of the driver's head. The CPU 51 knows the movement direction and the movement amount of the driver's head in the front-rear, left-right and diagonal directions based on the outputs of the head front-rear movement sensor 58 and the head left-right movement sensor 59. The electrocardiogram waveform sensor 60 detects the electrocardiogram waveform of the driver sitting in the driver's seat and outputs electrocardiogram waveform data. For example, the ECG waveform sensor 60 for measuring the ECG waveform data of the driver in a non-contact manner is disclosed in Japanese Patent No. 4738958 (electrocardiogram measurement device), Japanese Patent No. 5368904 (vehicle electrocardiography measurement device), and the like.

As shown in FIG. 2, the safety device 50 is roughly divided into a driver abnormality occurrence detector 1 and a safety ensuring unit 10 that operates in response to an abnormality occurrence detection signal output from the driver abnormality occurrence detector 1. It consists of two functional blocks.

The driver abnormality occurrence detector 1 includes a sensor 2, a confirmation unit 3, and a special monitoring mode control unit 4. The sensor 2 includes the head longitudinal movement sensor 58, the head lateral movement sensor 59, and the electrocardiogram waveform sensor 60 shown in FIG. 1, and detects changes in the posture of the driver and the occurrence of abnormalities in the heart. The confirming unit 3 is a driver's posture change when the detected posture change is a presumed abnormality occurrence and the amount of change exceeds a predetermined range, and when an abnormality is detected in the heart. Confirmation of whether or not there is an abnormality is output, and if there is no response, an abnormality detection signal is output. The special monitoring mode control unit 4 determines a range that is narrower than the predetermined range until a predetermined time T1 elapses when there is a response from the driver that no abnormality has occurred in response to the confirmation request, When the amount of change in posture exceeds the narrow range, the confirmation unit 3 causes the driver to confirm whether or not an abnormality has occurred. The confirmation unit 3 is realized by the CPU 51 executing a control program recorded in the ROM 52 and displaying a confirmation screen and a touch button on the touch panel display monitor 56. The special monitoring mode control unit 4 is realized by the CPU 51 executing a control program recorded in the ROM 52.

The safety ensuring unit 10 executes a control program recorded in the ROM 52 by the CPU 51, sounds a warning sound from a speaker included in the display monitor 56, controls the brake control unit 54 to apply the brake, and turns on the hazard lamp 55. This is realized by controlling the engine control unit 57 to reduce the fuel supply amount to the engine.

As shown in FIG. 3, a head back-and-forth movement sensor 58 that detects the amount of movement of the head of the driver 200 in the back-and-forth direction of the driver 200 is provided on the backrest portion of the driver's seat of the car 100. An electrocardiogram waveform sensor 60 for obtaining the electrocardiogram waveform data of the driver 200 is provided slightly below. As the head longitudinal movement sensor 60, for example, an infrared distance sensor is used. The electrocardiogram waveform sensor 60 is preferably a non-contact type as shown in the figure, but is not limited to this, and an electrocardiogram waveform sensor 60 that directly attaches an electrode to the driver 200 for measurement can also be used.

Near the front panel of the car 100, a head left-right motion sensor 59 is provided, and an obstacle sensor 61 is provided in front of the body of the car 100, for example, in front of the engine room or inside the front bumper. The head left / right movement sensor 59 has, for example, an image sensor, and uses a sensor that can recognize the head of the driver 200 by image processing and obtain the movement direction and movement amount of the left / right movement. As the obstacle sensor 61, for example, an ultrasonic sensor is used. An example of the arrangement positions of the head lateral movement sensor 59 and the obstacle sensor 61 is shown in FIG.

The driver abnormality occurrence detector 1 takes into account the case where the driver 200 has a demand-type cardiac pacemaker 201.

FIG. 5 shows a main routine of the control program recorded in the ROM 52, which is executed by the CPU 51. First, it waits for the engine to start (No in step S1). When the engine is started (Yes in step S1), the sensor is initialized by setting the mode value mode = 0 (step S2). The driver 200 does not detect the posture change that may occur during normal driving, but detects a posture change when the boat is standing on the boat, a posture change that is tired and leans forward, or a posture change that moves backwards as an abnormal occurrence. As described above, the threshold value of the amount of movement that the head longitudinal movement sensor 58 and the head lateral movement sensor 59 determine that an abnormality has occurred is set. The CPU 51 determines that an abnormality has occurred when there is a change in the posture of the movement amount exceeding the threshold. The amount of travel is determined based on the fact that most drivers drive with little movement of their heads unless otherwise noted. That is, each of the

sensors

58 and 59 recognizes the position of the head of the driver 200 as a reference position at the start of driving and at predetermined intervals, and the movement distance from the reference position caused by the posture change is a movement amount. Detect as. In order to prevent erroneous detection, the value is set to a value that is larger than the amount of movement that can frequently occur during normal operation and that the sensitivity does not become too low. The specific value is determined based on experimental data on the detection rate of occurrence of abnormality and erroneous detection. The range in which it is determined that an abnormality has occurred is determined by the movement amount threshold value.

After setting a movement amount threshold value for determining that an abnormality has occurred, the

sensors

58, 59, 60, 61 are started (step S3). Based on the detection values of the head longitudinal movement sensor 58 and the head lateral movement sensor 59, it is recognized how much the driver 200's head has moved in the direction indicated by the double arrows 210 to 215 shown in FIG. Further, the ECG waveform sensor 60 acquires ECG waveform data of the driver 200 and checks whether there is any abnormality. As a result, the orientation change direction of the driver 200 is a direction other than the double arrow 210 detected by the change in posture when operating the car navigation system, the change in posture when lighting the cigarette, for example, in the direction of the double arrow 212. If there is a threshold value for a predetermined movement amount that is larger than the movement amount of the posture change caused by the conversation performed in the conversation (Yes in step S4), the driver has exceeded the range to determine that an abnormality has occurred. An alert operation for confirming whether or not an abnormality has occurred in 200 is executed (step S5). Specifically, the safety confirmation screen shown in FIG. 7 is displayed on the touch panel display monitor 56. When the safety confirmation button 59a is pressed (touched) by the driver (Yes in step S6), the process proceeds to the process of setting the special monitoring mode in steps S8 to S10. On the other hand, if the touch button 59a is not pressed within a predetermined time T0 (for example, 20 seconds) and there is no response from the driver 200 (No in step S6), an abnormality detection signal is output, and the safety in step S7 is performed. Execute the reservation process.

When the posture change detected by the

sensors

58 and 59 in Steps S5 and S6 is a presumed posture change when the abnormality occurs, and the amount of change exceeds a predetermined range, the CPU 51 notifies the driver. A confirmation as to whether or not an abnormality has occurred is obtained, and when there is no response within a predetermined time T0, it functions as a confirmation unit that outputs an abnormality detection signal.

On the other hand, when no head movement is detected (No in step S4), an abnormality of the heart is detected from the ECG waveform data detected by the ECG waveform sensor 60. As shown in FIG. 8A, for example, when a normal heartbeat 251 is detected by a well-known waveform recognition technique, a heartbeat is detected when a stimulation signal (spike) 251 starts to be detected. This is detected when the demand-type pacemaker is activated because it has disappeared. Further, for example, as shown in FIG. 8B, when the normal heartbeat 253 is detected, as shown in FIG. 8B, when the arrhythmia 254 is detected, the normal heartbeat 255 is detected as shown in FIG. As detected, when ventricular fibrillation 256 is detected, it is further detected as when atrial fibrillation 258 is detected in arrhythmia 257 as shown in FIG. Refer to FIG. 5 again. When the operation of the pacemaker is detected (Yes in step S11), or when arrhythmia, ventricular fibrillation or atrial fibrillation is detected (Yes in step S12), the alert operation processing in step S5 is executed. If the pacemaker operation is not detected from the ECG waveform data detected by the ECG waveform sensor 60 (No in step S11), and no arrhythmia, ventricular fibrillation or atrial fibrillation is detected (No in step S12), the engine Until the operation is stopped (No in step S13), the process returns to step S4, and the processes in steps S4 to S7 and S11 to S13 are repeated. When the engine is stopped (Yes in step S13), the control program is terminated (step S14). In the case of an abnormality in the heart, sudden death due to acute heart failure may be considered. Therefore, when the abnormality is detected (Yes in Step S12), the CPU 51 performs an alert operation (Step S5) and then determines in advance in Step S6. Alternatively, a configuration may be adopted in which the time T0 is temporarily set to 0 without waiting for the elapse of the time T0 and the process immediately proceeds to the safety ensuring process in step 7 (No in step S6).

An alert operation process is performed in step S4, and after the safety confirmation button 59a is pressed (touched) by the driver 200, or the safety confirmation button 59a is not pressed by the driver, a safety ensuring process (step S7) is executed. After that, the mode value mode = 1 is set and the special monitoring mode is turned on (step S8). As shown in FIG. 9, when the special monitoring mode is not set (mode = 0), when there is a change in posture beyond the range indicated by the double-headed arrow 212 (for example, 20 cm), the boat is depressed and the boat is caught. It is determined that there has been a change in posture while being tired, a change in posture of being tired and leaning forward, or a change in posture of sliding backward. A range indicated by a double-headed arrow 212 is wider than a range of posture change (for example, 10 cm) caused by a conversation performed in conversation, which is indicated by a double-headed arrow 220. When the special monitoring mode is set (mode = 1), the movement amount threshold value is low, that is, the range where it is determined that an abnormality has occurred is narrowed to the range indicated by the double-headed arrow 221 (for example, 15 cm), and the abnormality is detected with fewer posture changes. It is set so that it is determined to occur. Until a predetermined time T1 (for example, 40 minutes) elapses (No in step S9), the process returns to step S4, and the processes of steps S4 to S9 and S11 to S14 are repeated. When the predetermined time T1 has elapsed (Yes in step S9), the mode value is returned to mode = 0, the special monitoring mode is turned off (step S10), and the process returns to step S4.

In steps S8 to S10, when a response indicating that no abnormality has occurred is received from the driver (Yes in step S6), the CPU 51 passes a predetermined time T1. Until this time, a range that is narrower than the predetermined range is defined, and when the narrow range is exceeded, the special monitoring mode control that causes the confirmation unit to confirm whether or not an abnormality has occurred to the driver It functions as a part.

FIG. 10 shows a subroutine of the safety ensuring process (step S7). When an abnormality occurrence detection signal is received according to the process of step S6 (Yes in step S20), the vehicle 100 is decelerated to stop the movement, and a safety ensuring process for ensuring the safety of the driver is executed. First, a warning sound is emitted from a speaker provided in the display monitor 56 (step S21). The warning sound may be either a sound or an alarm sound or both. At this time, the display screen of the display monitor 56 is flashed on and off, and the driver notices and prompts the user to step on the brake. Next, the hazard lamp 55 is blinked (step S22). The traveling speed is confirmed from the engine control unit 57 (step S23). A stop process according to the traveling speed is performed (step S24). Specifically, the engine control unit 57 is controlled to stop the fuel supply to the engine, and the brake control unit 54 is controlled to prevent sudden braking for the driver and the following vehicle, but the movement should be stopped as short as possible. To brake. When an obstacle such as a person, a car, or a building is confirmed ahead by the obstacle sensor 61 (Yes in step S25), the vehicle 100 is suddenly braked to stop before colliding with the obstacle as an emergency stop process. Is applied (step S26). If no obstacle is detected (No in step S25), the stop process in step S24 is continued. If the automobile 100 is not stopped (No in step S27) and the brake is not depressed (No in step S28), the process returns to step S21. If the vehicle has not stopped yet (No in step S27), but the driver 200 notices and steps on the brake (Yes in step S28), the process returns to step S5 of the main routine shown in FIG. 5 to perform the alert operation process. . When the automobile 100 stops (Yes in step S27), the warning sound is stopped (step S29), the process returns to the main routine, and the process proceeds to step S8.

The CPU 51 stops the automobile 100 according to the abnormality detection signal while executing the safety ensuring process (steps S20 to S29) in step S7, and an obstacle is detected ahead by the obstacle sensor. When the vehicle is present, the vehicle functions as a safety ensuring unit that urgently stops the automobile 100 before colliding with the obstacle.

By executing the above processing, the driver abnormality detection detector 1 performs a relatively loose monitoring under a situation where there is little suspicion of the occurrence of an abnormality, thereby erroneously detecting an operation performed during normal driving as an abnormality occurrence. On the other hand, in a situation where there is a possibility of occurrence of an abnormality, the detection accuracy of the occurrence of the abnormality is increased by setting a special monitoring mode so as to be highly sensitive. The driver abnormality occurrence detector 1 and the safety device 50 using the same can detect the occurrence of an abnormality more accurately when a serious state occurs after the first posture change. With this function, the automobile 100 equipped with the safety device 50 can protect not only the driver's safety but also the lives of pedestrians around.

The present invention is not limited to the configurations of the various embodiments described above, and various modifications can be made without departing from the spirit of the invention. For example, a demand-type cardiac pacemaker only performs a sensing operation in the case of a normal natural pulse and does not output a signal, but periodically outputs an electrical stimulation signal (spike) when an arrhythmia is detected. Similar to a general electric circuit, signal noise is radiated with the output of the electrical stimulation signal. Some recent pacemakers have a communication function to enable monitoring of an electrocardiogram waveform for 24 hours. In addition to the electrocardiogram waveform sensor 61, in order to detect the guidance of the pacemaker, a sensor for detecting the output of the electrical stimulation signal from the signal noise and the signal generated by the communication function may be provided.

The use of the driver abnormality occurrence detector 1 according to the present invention is not limited to the automobile 100, but is used for all vehicles that need to detect the state of the driver's poor physical condition, doze, poor heart, etc., and ensure safety. be able to.

DESCRIPTION OF SYMBOLS 1 Driver abnormality generation detector 2 Sensor 3 Check part 4 Special monitoring mode control part 10 Safety ensuring part 50 Safety device 51 CPU
52 ROM
53 RAM
54 Brake Control Unit 55 Hazard Lamp 56 Touch Panel Display Monitor 57 Engine Control Unit 58 Head Longitudinal Movement Sensor 59 Head Left / Right Movement Sensor 60 ECG Waveform Sensor 61 Obstacle Sensor 100 Automobile

Claims

In the driver abnormality detection detector that detects that an abnormality has occurred in the driver while driving the vehicle,
A posture change sensor for detecting a change in the posture of the driver;
When the detected posture change is a posture change at the time of occurrence of an abnormality that is assumed in advance and the amount of change exceeds a predetermined range, the driver is confirmed as to whether or not an abnormality has occurred. If there is no response, a confirmation unit that outputs an abnormality detection signal,
If there is a response from the driver indicating that no abnormality has occurred in response to the request for confirmation, a range narrower than the predetermined range is determined and the narrow range is exceeded until a predetermined time T1 elapses. In this case, a driver abnormality occurrence detector, comprising: a special monitoring mode control unit that causes the confirmation unit to confirm whether or not an abnormality has occurred in the driver.
Equipped with an ECG waveform sensor that detects the ECG waveform of the driver,
The special monitoring mode control unit monitors an electrocardiogram waveform obtained by an electrocardiogram waveform sensor, and when the arrhythmia, ventricular fibrillation or atrial fibrillation is detected, whether or not the driver is abnormal in the confirmation unit, 2. The driver abnormality occurrence detector according to claim 1, wherein confirmation of whether or not is performed is performed.
Equipped with an ECG waveform sensor that detects the ECG waveform of the driver,
The special monitoring mode control unit monitors the electrocardiogram waveform obtained by the electrocardiogram waveform sensor, and detects that the driver's demand-type pacemaker is operating. The driver abnormality occurrence detector according to claim 1 or 2, wherein confirmation as to whether or not there is present is performed.
The driver abnormality occurrence detector according to any one of claims 1 to 3, wherein the predetermined time T1 is 40 minutes.
The driver abnormality occurrence detector according to any one of claims 1 to 4,
A safety device comprising: a safety ensuring unit that stops the vehicle when an abnormality occurrence detection signal is output by the confirmation unit of the driver abnormality occurrence detector.
It has an obstacle sensor that detects obstacles in front of the vehicle,
The safety device according to claim 5, wherein, when an obstacle is detected ahead by the obstacle sensor, the safety ensuring unit urgently stops the vehicle before colliding with the obstacle.