JPS6288006A - Obstacle evading device for unmanned conveyance vehicle - Google Patents

Abstract

PURPOSE:To increase the safety during a run by sensing an obstacle in the front and carrying out evading run operation in a run following up a guiding means, and returning the original run path and restarting a follow-up run. CONSTITUTION:An unmanned conveyance vehicle is equipped with a photoelectric sensor on its frame and a light reflection tape for guidance installed on the run path previously is sensed by the sensor to make a run on the run path while correcting the direction to right and left. In this case, an obstacle sensing means is provided on the front surface of the unmanned conveyance vehicle and on both right and left flanks and when an obstacle is sensed in the front, the guidance run is stopped and the vehicle begins to run to one side. When there is no obstacle sensed in the front after said obstacle is evaded, the sideward run is stopped and a forward run is started. Further, the obstacle sensing means on one flank senses an obstacle and then turns off, the forward run is stopped and a run to the other side is made until the position of the guide means on the run path. Consequently, the vehicle returns to the run path and begins to make the follow-up run.

Description

DETAILED DESCRIPTION OF THE INVENTION (Technical Field of the Invention) The present invention relates to an obstacle avoidance device for an automatic guided vehicle that travels by itself along a predetermined travel route following a guide means.

[Technical background of the invention and its problems] Conventionally, automated guided vehicles, such as self-propelled robot carts, have been used to travel along a predetermined travel path by following guidance means installed on a predetermined travel path. It has been known. In addition, such automated guided vehicles are equipped with a means to automatically stop traveling if there is an obstacle on the route of travel by detecting the obstacle using phototubes, ultrasonic waves, or other obstacle sensing means. However, there is no known vehicle equipped with an obstacle avoidance device that can avoid an obstacle when it is detected and return to the driving path after passing the obstacle.

[Purpose of the invention]

This invention has been made in view of such conventional problems, and includes obstacle sensing means provided at least on the front and both left and right sides of an automatic guided vehicle, and a control device included in the automatic guided vehicle detects each obstacle. An unmanned guided vehicle that avoids obstacles by running the automated guided vehicle sideways or forwards according to the operation of the object sensing means, and after avoiding the obstacles, returns to the traveling path and follows the guidance means. The purpose of the present invention is to provide an obstacle avoidance device for a guided vehicle.

[Structure of the Invention] As shown in FIG. Obstacle sensing means are installed on both the left and right sides of the vehicle, and when an obstacle is detected in front of the vehicle, guidance travel is stopped and the vehicle begins traveling to one side. When the obstacle sensing means on the side of the obstacle detects the obstacle and turns off, it stops traveling forward and returns to the original traveling path. The gist of the present invention is an obstacle avoidance device for an automatic guided vehicle, which is provided with a control means that travels in the opposite direction to the position of the guidance means and starts guidance travel again.

[Example I1M of the invention] FIGS. 2 to 4 show the entire photoelectric induction type automatic guided vehicle 1, in which a frame 3 is equipped with a photoelectric sensor 5, and this photoelectric sensor 5 is pre-aligned with the travel path R. The drive wheel 9 faces the guiding light reflecting tape 7 installed above, and the drive wheel 9 runs across this light reflecting tape 7. Then, it senses the left-right imbalance in the reflection intensity of the light projected from the photoelectric sensor 5 against the light-reflecting tape 7, and while correcting the direction of the automatic guided vehicle 1 to the right or left, the reflective tape 7 is always kept at the center. The vehicle travels on the driving route R in such a manner as to Note that this photoelectric type tracking traveling device employs the same type of system that is already known and widely used. In addition, an electromagnetic system is installed that automatically corrects the running direction based on the voltage difference between the pickup coils installed on the left and right side of the automatic guided vehicle 1 for the towpath wire laid on the running route R, so that the vehicle runs on a predetermined running route. It is also possible to use an inductive method.

As shown in FIG. 5, the drive wheels 9 of the automatic guided vehicle 1 are designed to be able to travel by themselves at least forward, left and right, and whether to travel in the front-rear direction or the left-right direction is determined by a control unit that will be described later. controlled by

Furthermore, obstacle sensing devices 11, 13, and 15 such as ultrasonic sensors or photoelectric sensors are attached to at least the upper part of the frame 3 of the automatic guided vehicle 1, and to both the left and right sides, respectively. The automatic guided vehicle 1 is equipped with a control unit CPU that processes signals from these obstacle sensing devices 11, 13, and 15 to drive the drive wheels 9 forward or left and right. Next, the obstacle avoidance operation of the automatic guided vehicle 1 by the control unit CPU will be explained based on the flowchart of FIG. 6 and the operation explanatory diagram of FIG. 7.

Normally, the guided vehicle 1 uses a charging guidance method, and the photoelectric sensor 5 detects the light-reflecting tape 7, and the vehicle 1 travels along the travel path R defined by the light-reflecting tape 7, one step 21 degrees. , when an obstacle S is placed in front of the vehicle as shown in FIG. Ru step 22
゜When an obstacle S is discovered in front in this manner, the positional relationship between the obstacle S and the transport vehicle 1 is determined. In other words, a plurality of obstacle sensing devices f! are provided on the left and right sides of the face of the transport vehicle 1! 211.11. . . . Depending on which of the left and right obstacle sensing devices is not working, it is determined whether it is better to move the transport vehicle 1 first to the right or to the left. In step 23. ．． 24° Here, the front obstacle sensing device 11.11. When all of... are operating in response, the predetermined direction is
Step 2 where movement starts to the right or left
5° The lateral movement started in this way is detected by the obstacle sensing devices 11, 11 . . . continue until all of them no longer respond, and then are stopped. In the state shown in FIG. 7(b), that is, while the conveyance vehicle 1 is moving to the right, Obstacle sensing device 11, 11. If the obstacle sensing device 15.15 installed on the right side operates in response to the right wall W while some of them are in operation, the obstacle sensing device 15. Movement is stopped, and movement to the left is started - step 28.29°, and in this movement in the opposite direction, the obstacle sensing devices ff111.11. When all of ... no longer respond, the obstacle S is assumed to have been cleared and the movement in the lateral direction is stopped - step 30.27° However, the front obstacle sensing device 11.11°... Obstacle sensing device 13 on the opposite side when some is still in operation
．． 13 reacts, this transport vehicle 1 is obstructed by the obstacle S.
It is determined that it is not possible to avoid the obstacle S to the right or left side, and the driver stops in front of the obstacle S because it is impossible to proceed. Conveyance to S! ! ! If it is determined that the obstacle S can be cleared by moving, for example, to the right, the front obstacle sensing device 11.11°... and the left and right obstacle sensing devices 13.15 will move. It is in the off state and the transport 111
After the movement in the lateral force direction of 1 is stopped, forward movement is started in one step 33°, and in this forward state, it passes one side of the obstacle S, but the obstacle Whether or not it has passed S is determined by the obstacle sensor 8 and 1 on the side of the vehicle 1 on the obstacle S side.
3. Judgment is made based on whether or not all of the obstacle sensing devices 13 are turned off after once sensing operation - step 34. Thus, when all the side obstacle sensing devices 13° 13 are turned off after once activated, the sensor shown in FIG. As shown in d), the conveyance vehicle 1 starts moving in the opposite direction to the original position of the light reflective tape 7, and starts tracking again by the photoelectric induction system - Steps 35-37. In this way, the conveyance vehicle 1 When there is an obstacle S on the predetermined guided travel path, the car 1 recognizes the position of the obstacle, avoids the obstacle S, passes by the side, returns to the travel path, and performs photoelectric guidance. This means that following-driving using the electric m-guide method or following-driving using the electric m-guidance method will be restarted.

The automated guided vehicle of the above embodiment can be used, for example, as a cart for a nursing care robot, and the robot picks up a patient and travels unmanned along a predetermined travel path using an electromagnetic induction method or a photoelectric induction method. In this case, when there is an obstacle in front of the robot, it is possible to realize a nursing assistance robot that is extremely useful and can avoid the obstacle by itself and return to the guiding path.

〔Effect of the invention〕

This invention allows an automatic guided vehicle to follow a guidance means and travel on a predetermined travel path to detect an obstacle in front of it, take an evasive action, and then return to its original position. The vehicle returns to the running path and resumes running by following the guidance means. Therefore, even if there are obstacles on the road, unmanned driving is possible, and safety during unmanned driving can be improved.

[Brief explanation of drawings]

Fig. 1 is a diagram corresponding to the claims of this invention, Fig. 2 is a front view of an automated guided vehicle used in an embodiment of the invention, Fig. 3 is a side view of the automated guided vehicle, and Fig. 4 is a diagram of the automated guided vehicle described above. FIG. 5 is a plan view showing the directions in which the automatic guided vehicle can travel, FIG. 6 is a flowchart showing the operation of the above embodiment, and FIG. 7 is a plan view explaining the operation of the above embodiment. . 1... Automatic guided vehicle 3... Frame 5... Photoelectric sensor 7... Light reflective tape 9... Drive wheel

Claims (3)

[Claims] (1) For an automatic guided vehicle that can travel on a predetermined travel path following a guidance means and can self-propel at least in both the forward and left and right directions, obstacle sensing means are provided at least on the front and on both left and right sides; When it detects an obstacle in front of it, it stops guided travel and starts traveling to one side, and when it no longer senses an obstacle in front of it, it stops traveling to the side and starts traveling forward. Then, when the obstacle sensing means on the side of the obstacle is turned off after sensing the obstacle, the vehicle stops traveling forward and travels in the opposite direction to the position of the guiding means on the original traveling route. An obstacle avoidance device for an automatic guided vehicle, comprising a control means for restarting guided travel. (2) A plurality of the obstacle sensing means are provided on the left and right sides of the front surface of the automatic guided vehicle, and when there is a side that is not sensitive to the left and right obstacle sensing means, the control means starts an initial movement in that direction; 2. The obstacle avoidance device for an automatic guided vehicle according to claim 1, wherein when the obstacle sensing means in both the left and right directions are equally sensitive, the device starts the initial movement to any one side. (3) When the automatic guided vehicle is moving sideways and the obstacle sensing means on the side located in front of the automatic guided vehicle senses an obstacle in the direction of movement, the control means stops moving sideways and moves to the opposite side. An obstacle avoidance device for an automatic guided vehicle according to claim 1 or 2, characterized in that the automatic guided vehicle starts moving in the opposite direction.