JP2689113B2 - Obstacle monitoring system for unmanned self-propelled vehicles - Google Patents

Description

Description: BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a course controller that calculates the position of a self-propelled body based on a detection signal from a position sensor, a calculated position of the self-propelled body, and a running schedule. It has a course controller that calculates an operation signal for following the planned traveling course when the course is separated from the course, and each actuator of the drive mechanism is operated based on a control signal from the course controller. The present invention relates to an obstacle monitoring system for an unmanned self-propelled body equipped with a drive controller for controlling. 2. Description of the Related Art Conventionally, a collision prevention device using ultrasonic waves or infrared rays has been known as one of the safe traveling measures for a vehicle that is traveling unmanned, but it is still proposed that a sufficient safety measure is taken. It was not done, and development was awaited in this kind of field. Further, there is known a configuration in which the emergency braking is mechanically performed when the braking operation does not operate due to a failure, but it is not possible to judge by the distance to the obstacle. SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances. When a self-propelled vehicle is automatically driven by a computer program, an obstacle sensor is used to detect an obstacle on the path. The presence or absence and the distance to the obstacle are detected, and based on this information, it is transferred to the course controller that guides and controls the traveling of the self-propelled body, and the self-propelled body is stopped by itself, and even if it approaches the obstacle, it does not stop. It is a main object to provide an obstacle monitoring system for an unmanned self-propelled body that can be stopped in an emergency. Means for Solving the Problems In order to solve the above-mentioned problems, the present invention provides (a). The location controller 12 which calculates the position of the self-propelled body based on the detection signal from the position sensor 11 is compared with the calculated position of the self-propelled body and the planned traveling course. In an obstacle monitoring system for an unmanned self-propelled body, which has a course controller 13 that calculates an operation signal to follow the course, and a drive controller 14 that controls each actuator 15 of the drive mechanism based on a control signal from the course controller 13 (B). As the obstacle detection sensor, a non-contact type short distance sensor 2 and a long distance sensor 3 and a contact type touch sensor 4 are used (c). For the signal detected by the obstacle detection sensor, the obstacle determination means 5 calculates the distance between the detected object and the self-propelled body,
It is determined whether or not the self-propelled body is an obstacle on the planned traveling course from now on, and when it is determined that the self-propelled body is an obstacle, the obstacle distance measuring means 6 determines the latest self-propelled body. The distance to the obstacle is calculated, and the calculation result is the course controller
13 and (d). In the course controller 13, based on the input distance data to the obstacle, the distance to the obstacle is slower than the vehicle speed of the self-propelled vehicle so that it does not slip and the obstacle creeping distance required to stop. When approaching more closely, change the vehicle speed of the self-propelled vehicle to a creeping speed that can be stopped immediately by braking, so that the distance to the obstacle is closer than the obstacle creeping distance and stops before a certain distance of the obstacle When the braking distance required for (1) is reached, the actuator 15 is controlled via the drive controller 14 to perform braking or traveling control to stop the self-propelled body, (e). Data measured by the obstacle distance measuring means 6,
The data detected by the touch sensor 4 is input to the emergency stop means 7, and the distance data to the obstacle measured by the obstacle distance measuring means 6 and the position sensor (not shown) are detected. Based on the speed of the self-propelled body and the state of forward and backward movement, it is determined that the distance to the obstacle has entered within the collision danger interval closer than the braking distance, and the brake control for stopping the self-propelled body is performed. If the brake control is not performed by detecting whether or not the actuator 15 is directly controlled, the self-propelled body is emergency stopped, or the actuator 15 is immediately controlled when the obstacle is detected by the touch sensor 4. Then, the technical measure is taken to stop the self-propelled body in an emergency. When the self-propelled body gradually approaches the obstacle, the obstacle is detected by the obstacle detection sensor, and the obstacle determination means 5 calculates the distance between the detected object and the self-propelled body. It is determined whether or not it will be an obstacle on the planned traveling course to be advanced. Next, when it is determined that an obstacle is present, the obstacle distance measuring means 6
Then, the distance between the latest self-propelled body and the obstacle is calculated, the calculation result is output to the course controller 13, and the control is performed in the following procedure based on the input distance data to the obstacle. First, if the distance to the obstacle exceeds the creeping distance of the obstacle required to stop by decelerating to the extent that it does not slip from the current vehicle speed of the self-propelled body, Continue running by changing the vehicle speed to a creep speed that can be stopped immediately rather than braking. The distance to the obstacle is closer than the creeping distance of the obstacle,
When the braking distance required to stop before a certain distance of the obstacle is reached, the actuator 15 is controlled via the drive controller 14 to perform braking or traveling control to stop the self-propelled body. Further, the distance to the obstacle is measured based on the distance data to the obstacle measured by the obstacle distance measuring means 6 and the speed of the self-propelled body detected by a sensor (not shown) and the state of forward and backward movement. Is determined to have entered within a collision risk interval closer than the braking distance, and whether or not the brake control for stopping the self-propelled body is performed and the brake control is not performed, an emergency The stopping means 7 directly controls the actuator 15 to make an emergency stop of the self-propelled body. Further, when the touch sensor 4 detects an obstacle, the emergency stop means 7 immediately controls the actuator 15 to stop the self-propelled body in an emergency. [Embodiment] A preferred embodiment in which an obstacle monitoring system for an unmanned self-propelled body according to the present invention is used in an off-highway truck (hereinafter referred to as a dump truck) will be described below with reference to the drawings from FIG. 2 onward. explain. In FIG. 2, the dump truck D has a position sensor 11
It has a location controller 12, a course controller 13, and a drive controller 14, and runs unmanned by self-guidance. The position sensor 11 includes a relative position sensor and an absolute position sensor. The relative position sensor is a speed sensor (a transmission speed sensor in this embodiment) 11a.
Then, the gyro compass 11b and the forward / backward movement sensor 11b 'determine the moving distance and the absolute azimuth of the dump truck D, and the location controller 12 determines the position coordinate (relative position coordinate) of the dump truck D based on the calculated position coordinate. Further, the absolute position sensor is composed of an infrared sensor 11c to reflect a signal to a reflecting mirror 11d of a gate located at a fixed position on a course to be traveled, and to determine the position coordinate (absolute position coordinate) of the dump truck based on the position coordinate of the gate. Then, the more accurate position coordinates are calculated by correcting the relative position coordinates. The position coordinates of the dump truck calculated in this way are input to the course controller 13 and are compared and calculated with a pre-stored running course. Then, the amount of deviation between the current position and the planned traveling course is calculated, and based on this, a traveling control signal for following the planned traveling course is output to the drive controller 14 via the communication section C to cause each actuator 15 to operate. It is operated to perform steering control and speed control. Here, the communication section C is a communication means,
It is also connected to other radio control devices and terminals, and outputs input signals from these to the drive controller 14. In this embodiment, the drive controller 14 includes a steering controller 14a that controls a steering angle, a speed controller 14b that controls a speed including stop, and a hydraulic pressure controller.
It is composed of a pneumatic controller (parking brake, etc.), electric components, a vehicle controller 14c for controlling a vessel and the like. As an obstacle detection sensor on this dump truck D,
A short distance sensor 2, a long distance sensor 3 and a touch sensor 4 are provided. That is, the short-range sensor 2 is an obstacle detection sensor in the vicinity of the vehicle. In the present embodiment, a well-known ultrasonic sensor capable of measuring and separating an obstacle having a wide directional angle and a wide range is used in front of the dump truck. It is arranged in three places in the center and on the left and right, and two places on the left and right in the rear. When a plurality of ultrasonic sensors 2 are provided and the respective directional ranges overlap, if they are operated at the same time, they interfere with each other and accurate obstacle detection cannot be performed. Therefore, in this system, each ultrasonic wave is detected by the obstacle controller 1 described later. The transmission timings of the sensors are shifted and controlled to prevent mutual interference. Next, in the case of this embodiment, the long-distance sensor 3 is composed of a laser radar. That is, the laser radar is a known distance measuring sensor using a laser diode, which can measure a distance over a longer distance than the ultrasonic sensor, and is provided in the front center of the dump truck. This is because when the dump truck D is traveling at a high speed, the distance required to stop the obstacle is longer than that during normal traveling, and therefore the vehicle is at a distance (a distance that cannot be detected by the ultrasonic sensor). It is provided because it is suitable for distance measurement to obstacles (at a distance). Further, the touch sensor 4 is a contact type sensor unlike the above non-contact type sensor, and in this embodiment, the touch sensor 4 is arranged at three positions, namely, at the front, rear and bottom of the dump truck. The touch sensor 4 has a function of detecting by contact of an obstacle approaching the dump truck D when the ultrasonic sensor 2 and the laser radar 3 have a failure due to an accident or the like, and a function of positioning the dump truck D. Have. The signals detected by these obstacle sensors 2 to 4 are output to the obstacle controller 1. The obstacle controller 1 is a microcomputer that controls the obstacle sensors 2 to 4, calculates a distance to the obstacle, and outputs obstacle information to the course controller 13. That is, as shown in FIG. 3, the obstacle controller 1 has a sensor control means 1a, an obstacle determination means 5, an obstacle distance measuring means 6, an emergency stop means 7, and a monitor means 1b. There is. Here, as described above, the sensor control means 1a shifts the transmission timings of the short-range sensor 2 so as not to interfere with each other, and controls the other sensors 3 and 4. The obstacle judging means 5 judges whether or not the object to be detected becomes an obstacle on the route, based on the detection signals inputted from the obstacle sensors 2 to 4, and the traveling course of the vehicle is determined. Within the area added with the predetermined safety area (width) (see Fig. 4),
It is determined whether or not there is an object to be detected, the object to be detected is determined to be an obstacle when it is within the region, and the others are determined to be non-obstacles. Next, the obstacle distance measuring unit 6 measures the distance between the dump truck and the obstacle. The obstacle information and the distance measured from the obstacle thus detected are output to the course controller 13 together with the speed and forward / backward movement state of the self-propelled body detected by the sensor. In the course controller 13, the obstacle avoidance control unit 13a
In step 1, based on the input information, whether to bypass the obstacle or stop until the obstacle is removed is selected, and the control signal of the drive mechanism based on the selection is determined. This determined control signal is the drive controller 14
Is output to In this avoidance control, in each traveling such as straight traveling and turning traveling, the distance to the obstacle is a predetermined margin to the distance required to stop the obstacle creeping distance, in other words, to the extent that it does not slip. When approaching from a distance that takes into consideration, the speed controller 14b outputs a control signal to decrease the governor opening, and the dump truck D is changed to a vehicle speed (obstacle creeping speed) at which it can be immediately stopped by braking. When the obstacle is farther than the obstacle creeping distance and continues for a predetermined time, the original (original) traveling condition is restored. Obstacle distance is closer than the obstacle creepage distance,
When approaching a certain distance to the obstacle before a certain distance (braking distance) with a margin added to the certain distance, a control signal is output from the speed controller 14b, the brake pressure increases, and deceleration / stop In addition, a control signal is also output from the vehicle controller 14c to operate the parking brake and stop the obstacle. When the dump truck is completely stopped and it is detected that the obstacle is sufficiently far distance (safety distance) or more and continues for a predetermined time, the original (original) traveling condition is restored. When an obstacle is detected by the touch sensor 4 described above, the emergency stop means 7 immediately determines that an emergency stop has occurred,
The aforementioned brake control is directly performed. As a result, in addition to the auxiliary obstacle avoidance function, as shown in FIG. 6, a convex wall such as a wheel stopper is provided near the opening edge of the hopper, and the dump truck moves backward to dump the load. In this case, there is a positive use method in which the stop position (brake timing) can be accurately determined depending on whether or not the touch sensor contacts the convex wall. In addition, as a method of avoiding obstacles, instead of stopping,
A configuration may be used in which the course controller 13 automatically designs a course that bypasses an obstacle and returns to the planned running course, and guides the dump truck along the bypass course. In addition to the above configuration, this system is provided with an emergency stop means 7. The emergency stop means 7 inputs the lever position of the transmission from the forward / rearward movement sensor 11b 'and the speed of the transmission from the speed sensor 11a as feedback through the transmission interface unit 8. Then, even if the self-propelled vehicle enters within the collision danger interval where the distance to the obstacle is closer than the braking distance, the speed controller 14a or the vehicle controller 14c still avoids the obstacle or stops the self-propelled object with respect to each actuator 15. When the traveling control is not performed, it has a double safety structure in which a control signal for directly controlling the actuators (relay valves) of the rear brake and the parking brake is output to brake and perform an emergency stop. In addition, reference numeral 1b in the drawing is a monitor means for checking the obstacle sensors 2 to 4, checking the system power supply drop, and checking the system operation by a watchdog timer to improve the reliability. Next, a flow chart of the main program of the obstacle controller will be described with reference to FIG. First, after initial setting is performed in step 1, it is checked in step 2 whether or not there is a communication request from the course controller 13. In this embodiment, a communication section C is provided between the course controller 13 and the obstacle controller 1, and the communication request signal is input via the communication section C. If there is a communication request, the previous distance measurement result calculated by the obstacle controller 1 in step 3 and other obstacle information are output to the course controller 13. That is, based on the detection signals input from the obstacle sensors 2 to 4, the obstacle determination means 5 determines that the detected object is an obstacle on the course of the course to be traveled. It is determined whether or not the communication is requested, and the communication is requested. When there is no communication request and after there is a communication request and the immediately preceding data is output, the distance to the obstacle on the route is calculated based on the latest detection signals of the obstacle sensors 2 to 4. Next, in step 4, it is determined whether or not the vehicle has entered the emergency stop area (danger area) based on the calculated distance to the obstacle calculated above and the speed and forward / backward movement data input from the transmission interface unit 8. Check. If it is determined to be dangerous, a safety check is performed in step 5. That is, whether or not the distance to the obstacle is closer to the obstacle than the creeping distance of the obstacle, in other words, the distance required to stop until the vehicle does not slip so that a predetermined margin is added, is determined. The determination is made, the decision to avoid the obstacle is made as described above, and the vehicle speed is reduced. When the obstacle distance measurement is closer than the obstacle creeping distance and is closer than the distance (braking distance) in which a certain amount of margin is added to the certain distance for stopping before the certain distance The self-propelled body is stopped when it is determined that the obstacle is stopped. If the self-propelled vehicle enters the collision danger interval that is closer to the obstacle than the braking distance, it is determined to be dangerous and the vehicle is immediately stopped as shown in step 6. In addition, even if an obstacle is detected by the touch sensor, an emergency stop is made immediately. If it is determined to be safe, the process returns to step 2 to determine whether or not there is a communication request, and the above procedure is repeated. Further, FIG. 5 (b) shows a flowchart of the timer interruption process. After the start, the timer is reset in step 1, the ultrasonic transmission trigger is output in step 2, and the vehicle speed is measured. It Then, the procedure returns to step 1 and the procedure is repeated. This procedure is interrupted by the main processing flow at predetermined intervals. EFFECTS OF THE INVENTION Since the present invention is configured as described above, even if there is an obstacle in the vicinity of the path of the self-propelled body traveling by self-guidance control, the short-distance sensor and the long-distance sensor are used regardless of traveling speed. The avoidance control can be performed in a state in which there is an interval required for stopping. Moreover, while using a touch sensor to take safety measures,
It can also be used to position the stop of a self-propelled body. When an obstacle is detected, the drive controller can be controlled by the course controller for unmanned traveling control to avoid obstacle detouring or traveling stop, and if the above control is not performed, The actuator can be directly controlled by the obstacle controller to brake the self-propelled body. As a result, the safety during unmanned traveling can be further enhanced.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a functional block diagram of an obstacle monitoring system for an unmanned self-propelled body according to the present invention, FIG. 2 (a) is a block diagram showing a preferred embodiment of the present invention, and FIG. ) Is a perspective view of the dump truck of the same embodiment, FIG. 3 is a block diagram showing the function of the obstacle controller, FIG. 4 is a view for explaining the safety area, and FIG. 5 (a) is a function of the obstacle controller. FIG. 6B is a flowchart showing interrupt processing, FIG.
FIG. 6 is an explanatory diagram showing a usage example of the touch sensor. 1 ... Obstacle controller 2 ... Short range sensor 3 ... Long range sensor 4 ... Touch sensor 5 ... Obstacle determination means 6 ... Obstacle distance measuring means 7 ... Emergency stop means 11 ... Position sensor 12 ...... Location controller 13 ...... Course controller 14 ...... Drive controller 15 ...... Actuator

   ────────────────────────────────────────────────── ─── Continuation of front page    (72) Inventor Mamoru Onda               1-2-3 Kita-Aoyama, Minato-ku, Tokyo               Inside Tapilla Mitsubishi Corporation (72) Inventor Kaiji Kumagai               2-3-3 Marunouchi, Chiyoda-ku, Tokyo               Nittetsu Mining Co., Ltd.                (56) References JP-A-61-201310 (JP, A)                 JP 62-269898 (JP, A)

Claims (1)

(57) [Claims] The location controller that calculates the position of the self-propelled body based on the detection signal from the position sensor is compared with the calculated position of the self-propelled body and the planned traveling course In an obstacle monitoring system of an unmanned self-propelled body, which has a course controller that calculates an operation signal to be followed and a drive controller that controls each actuator of the drive mechanism based on a control signal from the course controller, as an obstacle detection sensor , A non-contact type short distance sensor and a long distance sensor, and a contact type touch sensor, the signal detected by the obstacle detection sensor, the distance between the detection object and the self-propelled body by the obstacle determination means It is determined whether or not the self-propelled vehicle is on the planned course where the self-propelled vehicle is going to proceed and becomes an obstacle, and then it is determined as an obstacle. In this case, the distance between the latest self-propelled body and the obstacle is calculated by the obstacle distance measuring means, the calculation result is output to the course controller, and the course controller uses the input distance data to the obstacle as the basis. In addition, if the distance to the obstacle is closer than the creeping distance of the obstacle required to stop by decelerating to the extent that it does not slip from the vehicle speed of the self-propelled vehicle, immediately stop the vehicle speed of the self-propelled vehicle by braking. Change the creep speed so that the distance to the obstacle is closer than the creep distance of the obstacle,
When the braking distance required to stop before a certain distance of an obstacle is reached, the actuator is controlled via the drive controller to perform braking or traveling control to stop the self-propelled body. The data measured by the means and the data detected by the touch sensor are input to the emergency stop means, the distance data to the obstacle, the speed and the forward / backward movement state of the self-propelled body detected by the position sensor. Based on, it is determined that the distance to the obstacle has entered within the collision danger interval closer than the braking distance, and the brake control is performed by detecting whether or not the brake control for stopping the self-propelled body is performed. If not, the actuator is directly controlled to stop the self-propelled body in an emergency, or if an obstacle is detected by the touch sensor, the actuator is immediately activated. Obstacle monitoring system for an unmanned self-propelled body to control Eta and is characterized by comprising an emergency to stop the self-propelled body. 2. The creepage distance for obstacles is set to the distance required to stop the self-propelled body without slipping, plus an extra amount of distance, and the braking distance is set for stopping before a certain distance to the obstacle. The obstacle monitoring system for an unmanned self-propelled vehicle according to claim 1, wherein the obstacle monitoring system is set by adding a margin distance. 3. Based on the distance data to the obstacle, the course controller automatically designs a course that bypasses the obstacle and returns to the planned course, and guides the self-propelled body along this bypass course. The obstacle monitoring system for an unmanned self-propelled body according to claim 1.