JPH0937403A - Electric vehicle - Google Patents

Abstract

(57) [Abstract] [PROBLEMS] To detect an obstacle that cannot be detected by an obstacle detection sensor and collide with an obstacle in a blind spot of an aircraft to perform an avoidance operation. SOLUTION: A traveling motor 7 that generates a propulsive force of an airframe 1
An obstacle detection sensor 2 provided on the outer periphery of the machine body 1 for detecting an obstacle, a direction change mechanism 4 for changing the traveling direction of the machine body 1, a traveling motor 7 and a direction change according to the output of the obstacle sensor 2. The control unit 9 controls the drive of the mechanism 4. The traveling motor 7 is provided with a motor rotation amount sensor 8 for detecting the rotation angle and the rotation direction of the traveling motor 7, and the control unit 9 controls the motor rotation amount sensor 8 when the obstacle detection sensor 2 detects no obstacle. When the decrease in the rotation speed of the traveling motor 7 or the stop of the rotation is detected by, the vehicle has an avoidance control function for controlling the drive of the direction changing mechanism and the traveling motor according to a predetermined obstacle avoiding operation procedure.

Description

Detailed Description of the Invention

[0001]

TECHNICAL FIELD The present invention relates to an electric vehicle,
In particular, the present invention relates to measures against collisions in electric vehicles and measures against running obstacles due to dust or the like.

[0002]

2. Description of the Related Art In a conventional electric vehicle, on the premise that obstacles do not enter into areas other than an area that can be detected by an obstacle detection sensor provided in the airframe,
It was configured to detect obstacles. Therefore,
The obstacle avoidance control is activated only when an obstacle is detected by the obstacle detection sensor mounted on the outer periphery of the machine body.

For example, in the technique disclosed in Japanese Patent Laid-Open No. 2-276402, a body of a small electric vehicle such as an electric wheelchair is equipped with a non-contact distance sensor for detecting a distance to an obstacle ahead. It is described that when the detected distance becomes equal to or less than a set value, the traveling speed reducer is controlled to decelerate to a predetermined low speed state.

Further, in Japanese Unexamined Patent Publication No. 3-131910, an unmanned vehicle traveling on a predetermined traveling route is provided with a sensor for detecting another unmanned vehicle, and one traveling is performed in a merging zone of the two traveling routes. It is described that the speed of the unmanned vehicle on the route is set to low, the presence of the unmanned vehicle on the other traveling route is checked by the sensor, the unmanned vehicle is stopped when it is detected, and the unmanned vehicle is passed when it is not detected. .

Further, in Japanese Unexamined Patent Publication No. 3-219310, a means for sending a stop signal to a reverse vehicle at the time of stop and a stop signal for a preceding vehicle to each of a plurality of unmanned vehicles traveling in a row on a traveling road. It is described that a means for receiving the signal and a control means for controlling the brake to perform the braking operation when the stop signal of the preceding vehicle is received.

[0006]

In the conventional electric vehicle, the obstacle avoidance control is activated only when an obstacle is detected by the obstacle detection sensor mounted on the outer periphery of the machine body. Therefore, if a collision with an obstacle occurs in a blind spot of the aircraft that cannot be detected by the obstacle detection sensor, the moving body does not perform the escape process without recognizing the obstacle, and the obstacle state is further deteriorated. There was a risk.

Further, in the case where a wheel rotation abnormality occurs due to clogging of the wheel rotation mechanism or the like, if the vehicle continues to run for a long time, the wheels may be locked, resulting in poor running. However, there is a problem that there is no method for detecting the state of the rotation mechanism of the wheel.

The present invention is intended to solve such a problem of the prior art, and by providing a function of monitoring the rotation state of the traveling motor in the electric vehicle, the obstacle detection sensor cannot detect the obstacle. By detecting a collision with an obstacle in the blind spot of the airframe, it is possible to perform an avoidance operation, and when the collision detection due to the motor rotation state is repeatedly generated, an alarm and a braking operation are performed. The purpose is to prevent the locked state of the wheels and to change the avoidance operation according to the traveling road.

[0009]

[Means for Solving the Problems]

(1) A traveling motor that generates propulsive force of the machine body, and an obstacle detection sensor that is provided on the outer periphery of the machine body and detects an obstacle,
The vehicle includes a direction changing mechanism that changes a traveling direction of the machine body, and a control unit that controls driving of the traveling motor and the direction changing mechanism according to an output of the obstacle sensor. Moreover, the traveling motor is provided with a motor rotation amount sensor that detects the rotation angle and the rotation direction of the traveling motor, and the control unit uses the motor rotation amount sensor to detect the obstacle when the obstacle is not detected by the obstacle detection sensor. An avoidance control function is provided for controlling the drive of the direction changing mechanism and the traveling motor according to a predetermined obstacle avoiding operation procedure when a decrease in the rotation speed of the traveling motor or a stop of the rotation is detected. Since the moving body generally travels by driving wheels driven by motors, the traveling motor transmits rotational force to the driving wheels.

Therefore, even if an obstacle collides with a blind spot on the outer periphery of the machine body that cannot be detected by the obstacle detection sensor,
By detecting this, the electric vehicle can be caused to perform a predetermined obstacle avoidance operation based on the operation of the control unit.

(2) In the case of (1), the control unit repeatedly detects the decrease in the rotation speed of the traveling motor or the stop of the rotation by the motor rotation amount sensor, and the obstacle detection sensor detects an obstacle. An alarm display control function for controlling the display of an alarm when not detected and a lock prevention function for decelerating the traveling motor to a predetermined low speed or a stopped state are provided.

Therefore, even if the wheel drive mechanism, which is a moving means of the electric vehicle, becomes difficult to move due to dust, it is possible to prevent the rotation of the wheels from being locked. it can.

(3) In the case of (1), the control unit has an operation procedure reading function for controlling the drive of the direction changing mechanism and the traveling motor based on the obstacle avoiding operation procedure inputted from the outside.

By adding an interface function to a host computer or the like, the control program of the control unit 9 can be changed without changing the mechanism of the electric vehicle, so that the electric movement can be performed according to the condition of the running road. You will be able to change the function of the car.

[0015]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described in detail below with reference to FIGS. FIG. 1 is a mounting view of an electric vehicle showing an embodiment of the present invention, and shows an overall configuration of the electric vehicle to which the present invention is applied.

A front center detection sensor 2a, which is a non-contact type object detection sensor, a left front detection sensor 2b, and a right front detection sensor 2c are provided on the front surface of the machine body 1, and the front direction of the machine body, respectively. Obstacles in the front left direction and the front right direction are detected (hereinafter, the sensors 2a to 2c are collectively referred to as an obstacle detection sensor 2).

The body 1 includes a direction changing mechanism 4 and rear wheels 5, 6
Move by rotating. The rear wheels 5 and 6 are driven by motors 7a and 7b provided on the respective axles (hereinafter, the motors 7a and 7b are collectively referred to as a traveling motor 7).

Here, as the direction changing mechanism 4, a front wheel 4 which can change the direction around the vertical axis 3 is used. If necessary, the right and left rear wheels may be driven separately to change the traveling direction of the machine body.

The traveling motor 7 is provided with motor rotation amount detection sensors 8a and 8b for replacing the rotation angle and the rotation direction with electric signals (hereinafter referred to as sensor 8).
a and 8b are collectively referred to as a rotation amount detection sensor 8.

FIG. 2 is an electrical block configuration diagram of an electric vehicle showing an embodiment of the present invention, and shows an electrical configuration corresponding to the mounting diagram shown in FIG.

The control unit 9 takes in signals from the obstacle detection sensor 2 and the motor rotation amount detection sensor 8 and outputs a command to the motor drive unit 10 which drives the traveling motor 7. The control unit 9 includes a CPU 9a that is a processing device that controls an arithmetic function and a timer function, a memory unit 9b that stores a control program of the CPU 9a and necessary data, an obstacle detection sensor 2, a rotation amount detection sensor 8, and a traveling motor. 7 and an interface unit 9c for interfacing with each other. Further, a battery 11 is mounted as a power source for each of these electric mechanisms.

The control procedure for the electric vehicle will be described below with reference to the flow charts of FIGS. 3 and 5 show the CPU when the electric vehicle of the present invention is running.
9a is a flow of processing, and the processing of FIGS. 3 and 5 proceeds in parallel.

FIG. 3 shows detection and avoidance of obstacles during running.
The escape process is shown by a flowchart. This process is performed in the following order.

<1> It is checked whether the obstacle detection sensor 2 is ON (obstacle detection). (Step 1)

<2> If the sensor 2 is OFF in step 1, the motor rotation amount calculated in the process of FIG. 5 described later is read (step 5), and the rotation of the traveling motor 7 is not stopped, or the traveling motor is stopped. It is checked whether or not 7 is rotating in the reverse direction (step 6), and when the traveling motor 7 is stopped or is rotating in the reverse direction, it is determined that the traveling motor 7 has collided with an obstacle, and a few centimeters at a low speed. Travel motor 7 to move backward
Is driven (step 7) to change the direction of the machine body 1 (step 3), and then the forward movement is restarted (step 4) and the process returns to step 1. If the traveling motor 7 is rotating normally in step 6, the process returns to step 1.

<3> When the sensor 2 is ON in step 2, if it is the front center 2a, proceed to step 7. If it is the front left 2b or the front right 2c, change the direction of the body 1 (step 3) and then move forward. It restarts (step 4) and returns to step 1.

FIG. 4 is a flow chart showing details of the direction changing process (step 3) shown in FIG.

<4> If the front center sensor 2a is turned on in step 2, or if the motor stops rotating or rotates in reverse in step 6, the left and right rotational speeds and rotational directions of the traveling motor 7 are changed. Thus, the vehicle body 1 starts to turn right (or left) (step 102).

If the left front sensor 2b is ON in step 2, the function of the left front sensor 2b is temporarily disabled (2
a and 2c are valid) (step 107), and step 1
A right turn is started similarly to 02 (step 108). If the front right sensor 2c is ON in step 2, the function of the front right sensor 2c is temporarily disabled (2a, 2b).
Is turned on) (step 107), and a left turn is started (step 108).

<5> The state of the obstacle detection sensor 2 is checked (step 103).

<6> In step 103, when the sensor 2 does not detect an obstacle, it is checked whether or not the turning is completed (step 106). If the turning is completed, the direction change is completed.

<7> When the sensor 2 is turned on in step 103, if it is the center 2a of the front surface, the vehicle moves backward by a few centimeters (step 105) and then returns to step 101 to start the direction change of the machine body 1 again to the left front. If 2b or right front 2c is ON, the process returns to step 101 and the direction change of the machine body 1 is started again.

FIG. 5 is a flowchart showing the process of calculating the motor rotation speed during traveling.

<8> First, a reference time for determining that the traveling motor 7 has stopped is set (step 20).
1).

<9> Next, after the timer built in the CPU 9a is cleared, counting is started (step 20).
2).

<10> Next, the motor rotation amount detection sensor 8
The state of is checked (step 203).

<11> In step 203, when the output indicating the rotation and the direction of the predetermined angle is obtained from the sensor 8, based on the count value of the timer at that time,
After the motor rotation speed is calculated (step 204), it is checked whether the traveling motor 7 is rotating backward (step 205). Considering that there is some unevenness on the road surface, only when the reverse rotation reaches a reference value that is several times the above-mentioned predetermined angle (checked in steps 207 and 208), due to external pressure such as collision, It is determined that the traveling motor 7 has rotated in the reverse direction, and the determination information is stored in the memory 9b.

<12> If the rotation of the traveling motor 7 by the predetermined angle is not recognized by the sensor 8 in step 203, it is checked whether or not the timer has finished counting (step 209), and the counting is finished. If so, it is determined that the corresponding traveling motor (7a or 7b) is stopped (step 210), and the determination information is stored in the memory 9
b.

The present invention is not limited to the above-described embodiment, and any changes can be made.
For example, the number and installation position of the obstacle detection sensor 2 may be changed, or the correspondence between the traveling motor 7 and the wheels may be such that both rear wheels are driven by one motor and the other motor steers the front wheels. Alternatively, each of the items can be replaced as long as it does not deviate from the gist of the present invention, such as changing the obstacle avoidance procedure after the obstacle detection by the obstacle detection sensor 2 or the motor rotation amount detection sensor 8. You can make any changes with.

FIG. 6 shows an example in which an alarm is displayed, and its electrical configuration is shown by a block diagram. In the figure,
Reference numeral 12 indicates an alarm display section, and 14 indicates a configuration in which a control function for the alarm display section 12 is added to the control section 9 shown in FIG.

If the detection of the collision object by the motor rotation amount sensor 8 occurs repeatedly several times while the collision object detection sensor 2 shown in FIG. 1 does not detect the obstacle, the control unit 14
Judges that the traveling environment is a bad condition, turns on the indicator light in the alarm display section 12 to call the driver's attention, and decelerates the traveling motor 7 to a predetermined low speed or a stopped state. .

By loading such a control program for the electric vehicle into the control unit 14 from, for example, the host computer, it becomes possible to execute the required operation.

FIG. 7 shows an example in which an avoidance operation is performed based on an obstacle avoidance operation procedure input from the outside, and its electrical configuration is shown in a block diagram. In the figure, 13 indicates a host interface unit, and 15 indicates a configuration in which a control function for the host interface unit 13 is added to the control unit 9 shown in FIG.

The host interface function of the controller 15 processes in parallel with other functions. When the host interface unit 13 receives from the host computer a command to transmit the mobile body control program,
The control unit 15 takes in the control program of the mobile unit through the host interface unit 13 and stores it in the memory 9b. After that, the control unit 15 starts controlling the moving body according to the control program stored in the memory 9b.

Here, the timing of reading the control program from the host computer, the timing of starting the operation of the program, and the like may be different from those in the above-described embodiments.

[0046]

As described above, according to the present invention, in the electric vehicle, the function of monitoring the rotation angle and direction of the motor for driving the wheels is added to reduce the rotation speed of the motor due to a collision. Since it is possible to detect the stop, even if the sensor for obstacle detection cannot detect it, even if the obstacle collides with the blind spot of the aircraft, it is possible to detect the collision and avoid the obstacle and escape. it can.

Further, when an obstacle is repeatedly detected due to a decrease or stop of the motor rotation speed, an alarm function for displaying this to the driver is added, so that dust is accumulated on the wheel drive mechanism. In addition, it is possible to prevent the rotation of the wheels from being locked.

Further, since the control program for the obstacle avoiding operation performed by the electric vehicle can be loaded from the host computer, it is easy to expand the function of the electric vehicle.

[Brief description of drawings]

FIG. 1 is a mounting view of an electric vehicle showing an embodiment of the present invention.

FIG. 2 is an electrical block configuration diagram of an electric vehicle showing one embodiment of the present invention.

FIG. 3 is a flowchart showing a process of obstacle detection, avoidance, and escape during traveling.

FIG. 4 is a flowchart showing details of a direction changing process.

FIG. 5 is a flowchart of a motor rotation speed calculation process during traveling.

FIG. 6 is a block diagram of an electrical configuration showing an embodiment of the present invention.

FIG. 7 is a block diagram of an electrical configuration showing another embodiment of the present invention.

[Explanation of symbols]

 1 Airframe 2 Fault detection sensor 4 Direction changing mechanism (front wheel) 7 Traveling motor 8 Motor rotation amount detection sensor 9 Controller

Claims (3)

[Claims] 1. A traveling motor for generating propulsive force of an airframe,
An obstacle detection sensor provided on the outer periphery of the machine body for detecting an obstacle, a direction change mechanism for changing the traveling direction of the machine body, and a drive for the traveling motor and the direction change mechanism according to the obstacle detection sensor output. In an electric vehicle including a control unit for controlling, the traveling motor is provided with a motor rotation amount sensor that detects a rotation angle and a rotation direction of the traveling motor, and the control unit causes an obstacle by the obstacle detection sensor. When an object is not detected, when the decrease in the rotation speed of the traveling motor or the stop of the rotation is detected by the motor rotation amount sensor, the direction changing mechanism and the traveling motor are driven according to a predetermined obstacle avoiding operation procedure. An electric vehicle having an avoidance control function for controlling. 2. The alarm is issued when the control unit repeatedly detects a decrease in the rotation speed of the traveling motor or a stop of the rotation by the motor rotation amount sensor, and the obstacle detection sensor does not detect an obstacle. 2. The electric vehicle according to claim 1, further comprising an alarm display control function for controlling the display of the display and a lock prevention function for controlling the traveling motor to decelerate to a predetermined low speed or a stopped state. 3. The control unit has an operation procedure reading function for controlling the drive of the direction changing mechanism and the traveling motor based on an obstacle avoiding operation procedure input from the outside. The electric vehicle described.