JPH0241891A - Preventing device for collision of manipulator - Google Patents

Abstract

PURPOSE:To simplify the structure of the interference preventing device whole body of manipulator and to miniaturize the interference preventing device of the manipulator by providing a detection means detecting an obstruction approached to the manipulator arm according to the light receiving amt. received by a light receiving part. CONSTITUTION:The obstruction approached between the light emitting part 16 and light receiving part 18 of a manipulator arm 11 is detected by reducing the light receiving amt. onto the light receiving part 18 by cutting off the light emitted from the light emitting part 16. As a result, the collision of the arm 11 and obstruction is evaded. The obstruction directly approached to the light emitting part 16 and light receiving part 18 presses these light emitting part 16 and light receiving part 18 against the energizing force of an energizing means, reducing the light receiving amt. of the light receiving part 18 similarly by energizing by moving in the direction orthogonal to the manipulator arm 11 surface, so the approach is detected. Consequently, the collision to the manipulator arm 11 is prevented.

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a collision prevention device used to prevent a collision of a manipulator such as a space manipulator.

(Prior Art) In general, a manipulator is equipped with a collision prevention device to prevent collisions with obstacles to ensure safety. As such a collision prevention device,
A light-emitting element and a light-receiving element are installed on the manipulator arm as an optical detection part, and when an obstacle approaches, the light emitted from the light-emitting element is reflected by the obstacle, and the reflected light is received by the light-receiving element. , a method was used to detect the approach of obstacles.

However, in the above-mentioned collision prevention device, since the detection range is only one point, when a wide range of detection is required, multiple detection units must be arranged over a wide range. It has the problem of being large. Furthermore, according to this, the amount of light received by the light receiving element differs depending on the reflectance of the surface of the obstacle, and there is a risk that light other than the amount of light from the light emitting part, such as sunlight, may enter the light receiving part. , there is a risk of malfunction.

This situation becomes a particularly big problem when applied to space manipulators that require high reliability. For example, in outer space, strong sunlight may not directly irradiate the light receiving part. This poses a problem in that it is easy to cause malfunctions.

(Problems to be Solved by the Invention) As described above, in the conventional collision prevention device, if detection is realized over a wide range, it becomes large because many detection parts have to be arranged. There was a risk of malfunction.

The present invention has been made in view of the above circumstances, and it is an object of the present invention to provide a collision prevention device for a manipulator that has a simple structure, can be made compact, and can realize highly accurate detection over a wide range. With the goal.

[Structure of the Invention] (Means for Solving the Problems) The present invention includes a pair of supporting members protruding from a manipulator arm, which are disposed facing each other with a predetermined interval, and which are provided so as to be freely removable and removable. a biasing means for biasing the arm surface in a protruding direction; a light emitting section provided on one side of the support member; a light receiving section provided on the other side of the supporting member facing the light emitting section; and the light receiving section. and detecting means for detecting an obstacle approaching the manipulator arm according to the amount of light received by the manipulator arm.

(Function) According to the above +M configuration, an obstacle that approaches between the light emitting part and the light receiving part of the manipulator arm is detected by blocking the light from the light emitting part and reducing the amount of light received by the light receiving part. , collisions are prevented. The obstacle that directly approaches the light emitting part and the light receiving part presses the light emitting part and the light receiving part against the urging force of the urging means, and urges the light emitting part and the light receiving part to move in a direction perpendicular to the manipulator arm surface. This similarly reduces the light receiving aperture of the light receiving section, so that approach is detected and collision with the manipulator arm is prevented. Therefore, it is possible to prevent a wide range of obstacles from colliding between the pair of light emitting parts and light receiving parts which are arranged to face each other on the manipulator arm.

In addition, since the light receiving part is arranged opposite to the light emitting part and directly receives the light from the light emitting part, it is possible to prevent light such as sunlight from entering, and to reduce the reflectance of obstacles. Since it is not affected by the effects of

(Example) Hereinafter, an example of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a collision prevention device for a manipulator according to an embodiment of the present invention. In the figure, reference numeral 10 denotes a base portion (not shown) installed in a structure so as to be freely movable. This base 10
A manipulator arm 11 is connected to the manipulator arm 11 via a joint 12, and a holding section 13 called an end effector is provided at the tip thereof. A pair of support members 14a and 14b are arranged on the manipulator arm so as to protrude at a predetermined distance. This support member 14a.

14b is disposed to be movable in the directions of arrows A and B, which are substantially orthogonal to the manipulator arm surface, and has a biasing member 15.1 such as a spring at its base end, as shown in FIG.
5 is attached so as to apply a biasing force in the direction of arrow A.

Moreover, the support member 14a.

14b, a light emitting section 16 such as an LED is disposed on one of the supporting members 14a via an optical system 17a, and a light receiving section 18 such as a photodiode is disposed on the other supporting member 14b. It is arranged opposite to the section 16. These light emitting section 16 and light receiving section 18 are set at a desired detection position H (height dimension from the manipulator arm surface), and their optical axes X correspond to each other (see FIG. 3).

As shown in FIG. 4, the light emitting section 16 is connected to an oscillation circuit 19 via a switching transistor Q, and the light is modulated and emitted toward the light receiving section. On the other hand, when the light receiving section 18 receives light from the light emitting section 16, it generates a current corresponding to the amount of light received.

This current is led to a voltage conversion resistor R constituting the detection section and converted to a voltage signal, then amplified by an AC amplifier 20, and converted to a DC signal via a detection circuit 21 and an integration circuit 22. This DC signal is led to one connection end of the comparator 'r, 23. Here, the comparator 23 compares the human-powered DC signal with the DC voltage of the voltage source 24, and determines that, for example, when the + side is high, the output becomes high (H), and light is incident, and - When the side is high, the output becomes low (L), it is determined that no light is incident, and a detection signal is output to a control section (not shown).

In the above configuration, a drive mechanism (not shown) drives the base 10 or the joint 12 as shown in FIG.
When the obstacle 24 approaches between 4a and 14b, the light emitting part 1
The light emitted from the light receiving section 18 is blocked and the light received by the light receiving section 18 is blocked.

Then, the light receiving section 18 generates no current, and the voltage signal generated by the voltage conversion resistor R is reduced. As a result, the comparison r, 23 is the AC amplifier 20, the detection circuit 2
1 and the DC signal inputted through the integrating circuit 22 is reduced, the output thereof switches from a low state to a high state, and it is determined that the obstacle 24 has approached, and the control unit (not shown) detects this. Output a signal. Here, the control unit (not shown) stops the drive mechanism (not shown) to stop driving the base 10 or the joint 12, and the manipulator arm 1
1 from colliding with an obstacle 24.

Further, when the obstacle 24 approaches the manipulator arm 11 and comes into direct contact with the support members 14a and 14b, for example, as shown in FIG. When the member 14b is pressed against the obstacle 24, it is urged to move in the direction of arrow B against the urging force of the urging member 15, and the light emitted from the light emitting section 16 is prevented from entering the light receiving section 18. The generated current disappears. Then, the voltage signal generated by the voltage conversion resistor R is reduced.

As a result, the comparator 23 similarly reduces the input DC signal, switches its output from a low state to a high state, determines that an obstacle has approached, and sends it to a control unit (not shown). Outputs a detection signal. Here, the control unit (not shown) stops the drive mechanism (not shown) to stop driving the base 10 or the joint 12, and the manipulator arm 1
1 from colliding with an obstacle 24.

Note that the obstacle 24 is located at the support part shrine 1 where the light emitting part 16 is arranged.
48, the support part shrine 14a is moved and urged by the obstacle 24, and the light emitting part 1 is attached to the light receiving part 18.
When the light from 6 is no longer incident, the obstacle 24 is detected in the same way.
A detailed explanation thereof will be omitted.

In this way, the above-mentioned collision prevention device for a manipulator supports the pair of supporting members 14a and 14b on the manipulator arm 1.
A light emitting section 16 is disposed on one of the supporting members 14a, and a light receiving section 18 is disposed on the other supporting member 14b so that the optical axes X thereof correspond to each other. The light emitting section 16 receives the light from the light receiving section 18, and the obstacle 24 approaching the manipulator arm 11 is detected based on the amount of received light. Since it is possible to reliably prevent collisions with obstacles 24 over a wide range corresponding to the arrangement spacing of the set of light emitting parts 16 and light receiving parts 18, the detection range is only one point as in the conventional case. Miniaturization can be achieved as much as possible.

Also, according to this, the light receiving section 18 is arranged to face the light emitting section 16 and directly receives the light from the light emitting section 16, thereby preventing light such as sunlight from entering manually. Moreover, since it is not affected by the reflectance of obstacles, etc., malfunctions are reliably prevented and highly accurate detection is possible. This is particularly useful for use in outer space, where it may be exposed to particularly strong sunlight.

In addition, in the said Example, the support member 14a of a - set.

14b is provided with a light emitting section 16 and a light receiving section 18, respectively.
, 14b can be arranged around the manipulator arm 11 at predetermined intervals to prevent collisions in the entire surrounding area, and the number of the arrangement is as follows:
Various things have 61 abilities. Therefore, it goes without saying that the present invention is not limited to the embodiments described above, and that various modifications can be made without departing from the spirit of the invention.

[Effects of the Invention] As described in detail above, according to the present invention, there is provided a collision prevention device for a manipulator, which has a simple configuration, can be downsized, and can realize highly accurate detection over a wide range. can be provided.

[Brief explanation of the drawing]

FIG. 1 is a configuration diagram showing the appearance of a collision prevention device for a manipulator according to an embodiment of the present invention, and FIGS. 4 is a circuit diagram showing the detection system of FIG. 1, and FIG. 5 is an operation explanatory diagram shown to explain the operation of FIG. 1. 10... Base, 11... Manipulator arm, 1
2...Joint, 13...Holding part, 14a, 14b...
- Support member, 15... urging member, 16... light emitting part,
17a. 17b... Optical system, 18... Light receiving section, 19... Oscillation circuit, 20... AC amplifier, 21... Detection circuit,
22... Integrating circuit, 3... Comparator,

Claims (1)

[Claims] a pair of supporting members protrudingly provided on the manipulator arm so as to be freely removable and disposed facing each other with a predetermined interval; a biasing means for biasing the supporting members in a protruding direction with respect to the manipulator arm surface; A light emitting part provided on one side of the support member, a light receiving part provided opposite to the light emitting part on the other side of the supporting member, and an obstacle approaching the manipulator arm depending on the amount of light received by the light receiving part. A collision prevention device for a manipulator, comprising a detection means for detecting a collision.