JPH0430986A - Control device for hand - Google Patents

Abstract

PURPOSE:To surely perform the motions of placing and holding without a troublesome work, by storing at a memory part the height of a hand at the time when a work is mounted on a base with the decision at that time due to the reduction of the detect ion result of a weight sensor and controlling an arm based on the memory content of a memory part at the following, holding motion time of the work. CONSTITUTION:The reduction in the detection result of a weight sensor 8 is decided at a decision part 14 when placing a work 7 on a base 9. The height information on a hand 6 of the reduction time of the detection result of the weight sensor 8 by this decision part 14 is onece stored by a memory 15. Then, an arm 5 is controlled based on the memory content of this memory 15 at the following holding motion time of this work 7 and the hand 6 for holding the work is moved.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application The present invention relates to a hand control device for a so-called robot or the like.

(B) Conventional technology When gripping a workpiece with a hand attached to an arm, transporting and placing it on a table, etc., and then gripping the workpiece again with the hand, conventionally the arm was controlled in advance. A method is used in which the height position of the platform is taught to the control unit. However, with this method, it is necessary to accurately measure the height of the platform in advance, which is cumbersome, and furthermore, in the case where the arm is mounted on a movable trolley, changes in the tire diameter of the movable trolley There is a risk that the positional relationship in the height direction may shift due to such reasons, and reliable mounting and holding operations may not be possible.

(c) Problems to be Solved by the Invention The present invention provides a hand control device that can reliably perform mounting and holding operations without any troublesome work.

(d) Means for Solving the Problems The hand control device of the present invention includes a hand section that holds a workpiece, a weight sensor attached to the hand section that detects the weight of the workpiece, and a hand control device that moves the hand section. and a control unit that takes in information from the weight sensor and controls the operation of the hand unit and the arm unit,
The control unit includes a determination unit that determines whether the detection result of the weight sensor decreases when the workpiece is placed on the table, and a height of the hand unit when the detection result of the weight sensor decreases by the determination unit. and a storage section for storing information, and the arm section is controlled based on the contents stored in the storage section during the next holding operation of the workpiece.

(e) When placing the workpiece on the table, it is determined that the workpiece has been placed on the table due to a decrease in the detection result of the weight sensor, and the height information of the hand section at that time is stored in the memory. Ru. Then, during the next holding operation of the workpiece, the arm section is controlled based on the contents stored in the storage section.

(F) Embodiment The drawings show a mobile robot device which is an embodiment of the present invention.

FIG. 1 is a schematic diagram showing the overall configuration. Here, 1 is the main body of a moving trolley, which is moved on a floor surface 4 by means of moving means having wheels 2 and 3.

5 is an arm provided on the main body 1; 6 is a hand that is attached to the arm 5 and moves vertically and horizontally to hold a workpiece 7; 8 is attached to the hand 6 to detect the weight of the workpiece. 9 is a work table on which the workpiece 7 is placed; 10 is a control device that receives information from the microswitch 8 and controls the operation of the arm portion 5, the hand portion 6, and the above-mentioned moving means; Department.

The control unit 10 includes a microswitch 8 and an arm drive unit 1.
1. A computing device 14 that is connected to the hand drive section 12 and the moving means drive section 13 and controls them, and the computing device 1
4 and a storage section 15 for storing height information of the hand section as described later.

FIG. 2 is a perspective view showing the hand portion 6. FIG. The hand section 6 has two fingers 16 and 17 that are opened and closed by a hand section drive section 12 consisting of a motor or the like.
．． A microswitch 8 is attached to the upper surface of each of the switches 17, respectively. These microswitches 8 are connected to the fingers 16.1
7 are installed so that their heights are the same when placed horizontally.

FIG. 3 is a perspective view showing the work 7. FIG. The workpiece 7 is composed of a cylindrical part 18 and a collar part 19 provided at the upper periphery of the cylindrical part 18, and in some cases, another material is placed on the upper surface of the cylindrical part 18 and transported together with the workpiece 7.

Thus, the workpiece 7 is gripped by the hand portion 6 using the two fingers 16 and 17 of the cylindrical portion 1 below the collar portion 19 of the workpiece 7.
This is done by holding 8. At this time, the workpiece 7 is the finger 16.
It is lifted with the flange 19 placed on the top surface of 17,
The weight of the workpiece 7, that is, the weight of the workpiece 7, is the weight of the finger 16.1
It is supported by the upper surface of 7 via a microswitch 8. At this time, the fingers 16 and 17 do not grip the workpiece 7 strongly, but grip the cylindrical portion 18 lightly to the extent that the workpiece 7 does not shift. That is, when the arm part 5 descends and the workpiece 7
It is preferable to apply such force that when the lower surface of the cylindrical portion 18 touches the base 9, the fingers 16, 17 slide on the surface of the cylindrical portion 18. Then, with the hand section 6 gripping the workpiece 7, the weight of the workpiece 7 is detected by turning the microswitch 8 on and off.

FIG. 4 is a flowchart showing the control executed by the arithmetic unit 14 when placing the workpiece on the table and then holding the workpiece again. The operation will be described below with reference to FIG. 5, which shows the operation, and FIG. 6, which shows the operation of holding the workpiece 7 again.

First, it is determined that the hand unit 6 has already grasped the workpiece 7 and will move to place the workpiece 7 on the table 9 (S
1 step), and the hand section 6 is moved above the positioning point of the stand 9 (step S2). At this time, the microswitch 8 detects the weight of the workpiece 7 and is turned on (FIG. 5(a)).

Then, the hand section 6 is lowered (step S3).
. The lower surface of the workpiece 7 is on the stand 9 (Fig. 5(b))
In this case, the microswitch 8 is still in the on state, and the hand section 6 continues to descend (Step S4). When the hand portion 6 further descends and the micro switch 8 is turned off (the fifth
(C)), it is determined that the weight detected by the microswitch 8 has decreased (step S4). That is, this 8
The 4 steps correspond to the discrimination section.

When the microswitch 8 is turned off, the lowering of the hand section 6 is immediately stopped (step S5), and the height information of the hand section 6 at that time is stored in the storage section 15 (step S6).
step). Then, the fingers 16 and 17 of the hand section 6 are opened to release the workpiece 7, and the hand section 6 is moved back (step S7).

A predetermined operation is performed on the workpiece 7 on the table 9, and when the operation is completed, a determination is made to perform an operation to hold the workpiece 7 again (Sl step). At this time,
Note in step S6! Based on the height information of the hand section 6 stored in M51s, the hand section 6 is moved to the same height (step S8, FIG. 6(a)).

Then, the hand section 6 is moved forward (step S9, FIG. 6(b)), and the fingers 16 and 17 are closed to grasp the workpiece 7 (step S9, FIG. 6(b)).
Step S10), and raise the hand portion 6 (Step S11, FIG. 6(C)).

In addition, in the above operation, the movement of the hand section 6 is performed by the operation of the arm section 5.

According to this configuration, when placing the workpiece 7 on the stand 9, it is determined that the workpiece 7 has been placed on the stand 9 due to a decrease in the detection result of the microswitch 8 as a weight sensor, and the current The height information of the hand section 6 is stored in the storage section 15, and the information on the height of the hand section 6 is stored in the storage section 15 during the next holding operation of the workpiece 7.
Since the arm section 5 is controlled based on the memory contents of the table 9, there is no need to accurately measure the height of the table 9 before operation, and the height position of the table 9 is taught to the control section. may be an approximate value. In addition, even if the tire diameters of the wheels 2 and 3 change due to aging of the movable cart, the height information of the hand section 6 is provided each time the workpiece 7 is placed on the platform 9 and then held again. Since this is stored, there is no risk that the positional relationship in the height direction will shift and that reliable placement and holding operations will not be possible.

In this embodiment, a micro switch 8 is used as a weight sensor.
However, for example, a strain gauge or a pressure-sensitive conductive rubber may be used.

Further, as the height information of the hand section 6, for example, in a configuration in which the arm section 5 for moving the hand section 6 is driven by a pulse motor, the height information is calculated for the arm section drive section 11 including the pulse motor. The number of drive pulses provided by the device 14 can be used as height information.

(G) Effects of the Invention According to the present invention, when placing a workpiece on a table,
It is determined that the workpiece is on the table due to a decrease in the detection result of the weight sensor, and the height information of the hand section at that time is stored in the storage section, and the next time the workpiece is held, it is determined based on the contents stored in the storage section. Since the arm is controlled, there is no need to accurately measure the height of the stand before operation, and the hand control allows for reliable placement and holding operations without any troublesome work. equipment can be provided.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention, FIG. 1 is a schematic diagram showing the overall configuration of a mobile robot device in which the invention is implemented, FIG. 2 is a perspective view showing a hand section, and FIG. 3 is a perspective view showing a workpiece. ,
FIG. 4 is a flowchart showing the control executed by the arithmetic unit during operation, FIG. 5 is a side view showing the operation of placing the workpiece on the table, and FIG. 6 is a side view showing the operation of holding the workpiece again. 5... Arm part, 6... Hand part, 7... Workpiece, 8... Micro switch (weight sensor), 9...
Base, 10...Control unit, 14...Arithmetic unit, 15...
・Memory section.

Claims (1)

[Claims] (1) A hand section that holds a workpiece; a weight sensor attached to the hand section that detects the weight of the workpiece; an arm section that moves the hand section; and a hand section that receives information from the weight sensor; The control section includes a control section that controls the operation of the arm section, and the control section includes a determination section that determines a decrease in the detection result of the weight sensor when the workpiece is placed on the table, and and a storage section that stores height information of the hand section when the detection result of the weight sensor decreases, and the arm section is controlled based on the stored contents of the storage section during the next holding operation of the workpiece. hand control device.