JPS59152096A - Detector for obstacle of robot - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed description of the invention] The present invention relates to an obstacle detection device for a robot.

An obstacle sensor is often attached to the movable part (arm V) of an industrial robot to detect obstacles, but the obstacle sensor used in this case is:
A shape recognition sensor (image sensor, etc.) that can distinguish between the shape of an obstacle and the shape of other devices that are originally present is used. However, since shape recognition sensors are extremely expensive, the installation of shape recognition sensors increases the manufacturing cost of the entire robot, which poses a problem.

On the other hand, if an optical or ultrasonic proximity sensor is used as an obstacle sensor, it will be cheaper, but since it does not have the ability to recognize shapes, it will incorrectly judge that it is an obstacle even if it comes close to an existing device. Therefore, it cannot withstand use as a robot.

In view of the above-mentioned circumstances, the present invention provides an obstacle detection device for a robot that can distinguish between an obstacle and an object that originally exists while using an inexpensive proximity sensor. The detection area is the space in front of the moving direction where the object originally exists, and the MU recording/moving unit 9
a first proximity sensor that detects when the movable part approaches an object; Obstacle detection is performed based on the detection signal of the proximity sensor, and there is no obstacle '4! except that the first proximity sensor detects the object. The special feature is that it is equipped with a determination section that determines whether something is missing.

Embodiments of the present invention will be described below with reference to the drawings.

FIG. 1 is a plan view schematically showing the mechanical structure of one embodiment of the present invention, and FIG. 2 is a block diagram showing the electrical structure of the same embodiment.

In FIG. 1, 1 is the rotation axis, and 1a and 1t+ are the main axis and chuck, respectively. 2 is placed on lathe l
A multi-axis industrial robot (LJ) is equipped with a hand 2b installed at the tip of an arm 2a to grasp the unprocessed workpiece 4 on the workpiece table 3 and chuck it.
The workpiece 4 which has been transported to the chuck 1b and which has been processed is then transported to the workpiece stand 5 from the chuck 1b. As is well known, the arm 2a can turn left and right as shown by arrows in the figure, and can also move up and down with respect to the floor.

Reference numeral 6 denotes an ultrasonic sensor provided on the N side of the hand 2b (the side on the side in the direction of movement when turning left).
'It emits waves and receives reflected waves reflected by obstacles, etc. Reference numeral 7a denotes a light projector, which is provided close to the ultrasonic sensor 6 on the side surface of the hand 2b. This floodlight 7a
The irradiated light is received by a light receiver 7b provided on the lathe l when the arm 2a rotates and reaches the position shown by the broken line in the figure.

Further, the output signal of the light receiver 7b and the output signal of the ultrasonic sensor 6 are supplied to the determination section IO as shown in FIG. The determination unit 1O outputs an obstacle detection signal Sa when the ultrasonic sensor 6 receives a reflected wave and detects some object, that is, when the ultrasonic sensor 6 outputs a detection signal, and also outputs an obstacle detection signal Sa when the ultrasonic sensor 6 receives a reflected wave and detects an object. When the irradiation light from the projector 7a is received, the obstacle detection signal Sa is generated regardless of the detection result of the ultrasonic sensor 6.
It does not output any . Therefore, the determination unit IO outputs the obstacle detection signal 8a only when the light receiver 7b does not receive light and the ultrasonic sensor 6 receives a reflected wave. This obstacle detection No. 4M Sa is supplied to a robot stop mechanism (not shown), and when the robot stop mmu position object detection signal Sa is supplied, the arm 2hO) is stopped. In addition, as shown in FIG. 2, a light emitter 7a and a light receiver 7b
Transmissive optical sensor? 7 are made up.

Next, the robot 2 performs the operation of this embodiment on the workpiece table 3.
The process of grasping the upper unprocessed work 4, rotating the arm 2a counterclockwise, and transporting the work 4 to the position of the chuck 11) will be described as an example.

Until the arm 2a starts turning and reaches the position indicated by the broken line in the figure, the irradiated light from the projector 7a is received by the receiver 7b, and by the receiver 7b.
Therefore, the determination unit 1O outputs an obstacle detection signal Sa based on the output signal of the ultrasonic sensor 6. Therefore, if any obstacle exists in front of the hand 2b in the moving direction, the super transliteration sensor 6 detects it, and the determination unit 10 outputs the object detection signal Sa to the arm 2a, thereby stopping the arm 2a. Next, when the hand 2b reaches the position indicated by the broken line in the figure, the ultrasonic waves emitted by the ultrasonic sensor 6 are reflected by the intangible body of the lathe 10 and are received by the ultrasonic sensor 6 again.

Therefore, the determination unit 10 tries to output the position W object detection signal 8a, but at this time, the light receiving unit 7b receives the irradiation light from the throwing unit 7a, so the determination unit 10 does not output the obstacle detection signal 16 Sa. . In other words, do not make the wrong judgment that there is an obstacle. As a result, the arm 2a further rotates counterclockwise, and the workpiece 4 held by the hand 2b is transported to the position of the chuck lb.

Note that in place of the ultrasonic sensor 6 and the transmission type optical sensor 7 in this embodiment, for example, an electrostatic type sensor or a sensor using a laser may be used.Also, as a method for detecting an approaching object, a reflective type and a sensor using a laser may be used. Either transmission type may be used.

As explained above, according to the present invention, the first proximity detecting area is defined as the space in front of the moving direction of the robot movable part where the object originally exists, and detects the proximity of the movable part to the object. a second proximity sensor that detects the space in front of the moving direction as a detection area and detects when the binding front rotation unit approaches some object; and detects an obstacle based on a detection signal of the second proximity sensor. In addition to
@iJ Note: When the first proximity sensor detects an object, it is equipped with a determination section that determines whether there is an obstacle, so it can be manufactured at low cost, and it can distinguish between existing objects and obstacles. Can clearly identify objects.

[Brief explanation of drawings]

FIG. 1 is a plan view schematically showing the mechanical structure of an embodiment of the present invention, and FIG. 2 is a block diagram showing the electrical structure of the embodiment. 6... Ultrasonic sensor (second proximity sensor), 7...
Transparent S-type optical sensor (first proximity sensor), lO... determination section. Applicant Shinko 111 Machine Co., Ltd. Figure 1 Figure 2

Claims (1)

[Claims] In a robot obstacle detection device that detects an obstacle in front of a movable part of a robot in the direction of movement, the detection area is a space in front of the space in the direction of movement in which an object originally exists, and the movable part is detected as being in front of the object. Detect proximity 3
Based on the detection signal of the second proximity sensor 1B, the second proximity sensor whose detection area is the space in front of the moving direction, and which detects that the movable part AiJ approaches some object, In addition to detecting obstacles,
An obstacle detection device for a robot, characterized in that the device includes: a determination section that determines whether there is an obstacle unless the first proximity sensor detects an object.