JP3243009B2 - Control method and control device for movable part of robot - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a control method and a control device for a robot movable unit, and more particularly, to a table for retrieving the operation of a robot movable unit for each operation, and the operation in the table by an external command. The present invention relates to a control method and a control device for searching and executing a desired operation in a table.

[0002]

2. Description of the Related Art Conventionally, in order to cause a movable part of a robot, for example, a finger of a robot hand mechanism to perform an operation of gripping a workpiece, it is necessary to first describe the operation of the finger by a control program in the same manner as a robot controller. Further, there is a method of separately teaching the target position to the finger controller via the input / output interface with the host controller, or a method of sending operation data from the host controller by direct communication to the finger controller.

[0003]

However, in the above-mentioned conventional example, in the method described above, the operation of the finger of the robot hand mechanism itself is:
Although it does not require complicated operation and control as compared to the robot body, it is operated and controlled by the same control means as the robot body, so it tends to be overspecified (i.e., overspecification) when looking at only the robot hand mechanism. It is. : Also, the operation program of the fingers of the robot hand mechanism is scattered in the operation program of the robot main body, that is, the entire robot, which is very troublesome in assembling the operation program, and has a disadvantage that errors are easily caused. The difficulty of maintenance of this program can be applied to target position data taught separately. : Next, in the method (1), since the communication function is necessary for the higher-level controller for communication, there is a necessity that the controller becomes expensive.

The present invention has been proposed to solve the above-mentioned problems of the prior art, and an object of the present invention is to provide a control method and a control apparatus which enable the operation of a robot movable section to be designated by a simple search code. Things.

[0005]

Means for Solving the Problems The above-mentioned problems are solved,
In order to achieve the object, a method for controlling a movable portion of a robot according to the present invention includes a robot controller for controlling a robot.
Connected to the teaching device of the movable part of the robot,
A movable part controller for controlling the operation of the movable part of the robot
A method of controlling a movable part of a robot by
The operation command code of the movable part of the robot
Searchable in advance by the search code corresponding to the work
A storage step to remember,
A first communication step of receiving a search code, and the teaching device
Target position of the movable part of the robot, input numerically to
A second communication step of receiving a position from the teaching device;
An action corresponding to the search code received in the first communication step
Search for an operation command code, the search result and the second communication
Of the robot based on the target position received in the step
Control step of controlling the movable portion, the teaching device,
Movement of the robot received from the movable part of the robot
Displays the current location of the copy . Also, preferably, the second
In the communication step, the numerical value is further input to the teaching device.
Receiving the set target speed, and in the control step,
Searches for the operation instruction code corresponding to the code, and
Result, the target position, and the target speed.
Control the movable parts of the Also, preferably, the robot
Movable part is a finger of the robot hand,
In the second communication step, the teaching device further includes a numerical value.
Receiving the input target gripping force of the finger from the
In the control step, an operation instruction code corresponding to the search code is used.
Search result, the search result, the target position, and the target
The robot hand based on the speed and the target gripping force
And the fingers . Also, preferably, the search
The code consists of n serial bits.
At most 2 ^n-1 operations are described.

Further, the control device of the movable part of the robot according to the present invention comprises a robot controller for controlling the robot and the robot controller.
Connected to the teaching device of the movable part of the bot,
A movable part controller that controls the operation of the movable part of the bot
Control device for a movable part of a robot having
The operation instruction code of the movable part of the robot
Retrievable in advance by search code corresponding to
Storage means for performing the detection from the robot controller.
A first communication means for receiving a search code;
The target position of the movable part of the robot input by numerical values
Second communication means for receiving the
Operation corresponding to the search code received by the first communication means
Searching for an instruction code, and comparing the search result with the second communication
Of the robot based on the target position received in the step
Control means for controlling a moving part, wherein the teaching device is
The movable part of the robot received from the movable part of the robot
Displays the current location of . Also, preferably, the second
The communication means further includes a numerical value input to the teaching device.
Receiving the target speed, and the control means outputs the search code
Search for the operation instruction code corresponding to
Based on the target position and the target speed.
Control the moving parts. Further, preferably, the robot
The moving part is a finger of the robot hand, and the
The second communication means further inputs numerical values to the teaching device.
Receiving the determined target gripping force of the finger,
The stage searches for an operation instruction code corresponding to the search code
And the search result and the target position, the target speed, and the
The robot hand and the fin are determined based on the target gripping force.
Control the moth.

[0007]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. In this embodiment, “robot finger” is selected as an example of the movable part of the robot. <System Configuration> FIG. 1 shows a development example of a robot hand to which this embodiment is applied and its control device.

In FIG. 1, reference numeral 11 denotes a robot hand mechanism, reference numeral 12 denotes a finger included in the robot hand mechanism 11, which actually grips a work, and reference numeral 13 denotes a controller for controlling the robot hand mechanism 11. Reference numeral 14 denotes an assembly work robot having a robot hand mechanism, and reference numeral 15 denotes a controller that controls the assembly work robot 14. Reference numeral 16 is connected to a controller 13 for controlling the robot hand mechanism 11, and stores data such as a target position, a target speed, and a target gripping force for operating the robot hand mechanism 11 in a teaching data table of the controller 13 of the robot hand mechanism. It is a teaching device for registering or directly operating the robot hand mechanism 11, and 17 and 18 are interfaces of respective controllers. <Hand Mechanism> FIG. 2 is a schematic view of a robot hand mechanism having a pair of fingers as an example of a robot hand mechanism to be controlled.

The robot hand mechanism 11 has a main body 151 connected to the robot 14 for assembly work. The main body 151 is formed of a housing whose lower side is open, that is, a horizontal piece 151a located on the upper side, and left and right vertical pieces 151b and 151c which fall from the left and right ends of the horizontal piece 151a, respectively. Have been. A pair of guide rods 152a, 152b is disposed in a state where both ends are fixed to these left and right vertical pieces 151b, 151c, respectively, in a state of being vertically parallel to each other and extending along the horizontal direction. . These upper and lower guide rods 152
The pair of finger members 12a and 12b are slidably supported in the horizontal direction by the pair of finger members 12a and 12b.
These finger members 12a and 12b are formed so as to extend in the vertical direction.

Here, a reversible rotatable servomotor as a drive source for driving the pair of finger members 12a and 12b away from and approaching each other is provided on the right vertical piece 151c in the figure of the main body 151. Reference numeral 153 is attached so that a drive shaft (not shown) is driven to rotate around a horizontal axis. However, this is an example, and the servo motor 153
The mounting position may be any mounting method as long as the finger members 12a and 12b can be driven and do not interfere with them. This servo motor 153 has
A rotary encoder 154 for detecting the rotation amount is attached so that the rotation amount can be accurately defined. A drive shaft (not shown) of the servo motor 153 includes
The feed screw 155 is connected integrally with this. Here, the feed screw 155 includes a forward screw portion 155a located on the left side in the figure from the center and a reverse screw portion 15 located on the right side.
5b.

On the other hand, the pair of finger members 12a, 1
2b, the left finger member 12a has a forward thread portion 1
A screw hole 156a screwed to the screw 55a is formed, and a screw hole 156b screwed to the reverse screw 155b is formed in the right finger member 12b. In this way, the left finger member 12a is in the forward threaded portion 155a,
When the right finger member 12b is screwed into the reverse screw portion 155b, the feed screw 155 is driven to rotate clockwise, so that the two finger members 12a and 12b are rotated.
By separating from each other, the gripped work is released.

When the feed screw 155 is driven to rotate in the counterclockwise direction, the two finger members 12a and 12b come closer to each other, and the work is moved to the two finger members 1a and 1b.
It will be gripped between 2a and 12b. Conversely, for a cylindrical work, both finger members 12a,
It is easily conceivable that the above operation is reversed by separating and approaching 12b inside. A sensor 157 detects the origin positions of the finger members 12a and 12b. <Hand Controller> FIG. 3 is a control block diagram of the hand controller 13. Adder 30, multiplier 31, adder 32, multiplier 3
4, torque amplifier 26, motor 28, encoder 29,
The counter 27 and the differentiator 33 form a target position control loop. The command position _xd is set in a target position control loop, and current position information from a position counter 27 that calculates a current position based on a signal from an encoder 29 that detects a rotation amount of a servo motor 28 that drives the finger 12, and the target position an adder 30 calculating the difference between the position, by multiplying the position loop gain K _p, currently the speed information by differentiating the current position information from the position counter 27 is output by multiplying a position loop gain K _p and this The information from the adder 32, which takes the difference from the received information, is multiplied by a speed loop gain _Kv to obtain a speed command. The speed command passes through the torque amplifier 26, and becomes a current command. Is operated to make the work grip.

Next, when the finger 12 reaches the target position _xd , the command switch 25 is switched from the target position control loop to the gripping force control loop. Command gripping force f from teaching data
_d is set in the gripping force control loop to control the gripping force of the finger 12 until the gripping force reaches the target value.
To work. At this time, at the same time, the monitor 24 monitors the moving position of the finger 12 based on information from the position counter 27 that calculates the current position by a signal from the encoder 29, and the finger 12 does not grip the workpiece correctly. Or, when the workpiece is not gripped at all, since the finger 12 exceeds the set limit position 23, a gripping error signal is output, the processing is switched to the target position control loop, and the processing is ended. If the finger 12 correctly grips the workpiece in a state where the finger 12 has not reached the limit position x _d + x _e , a finger operation completion signal is output,
The command switch 25 is switched to the target position control loop, and the processing ends.

FIG. 4 is a configuration diagram of the robot hand mechanism controller 13. The CPU 41 manages the operation of the entire robot hand mechanism controller 13,
Reference numeral 2 stores a program for operating the robot hand mechanism 11 (FIG. 1). The RAM 43 stores a target position, a target speed, a commanded gripping force, a movement limit position, and the like input from the teaching panel 47 through the I / F 46. Is stored.

The I / F 44 is provided with an external input / output interface (the robot controller 15 for assembling work, the teaching device 16
Of the robot hand mechanism 11 and an end signal of the operation of the robot hand mechanism 11. The D / A 50 outputs the operation command signal from the ROM 42 to the D / A 50
The signal is A-converted, amplified by the AMP 51, and the servo motor 28 is driven. The encoder 29 detects the rotation amount of the servo motor 28 and sends a signal to the counter 27 and the F / F 48. A communication interface 45 connects the CPU 41, the ROM 42, and other components. <Teaching device> FIG. 5 shows a teaching device 16 for a robot hand mechanism.
1 shows an example of the operation panel of FIG.

Reference numeral 61 denotes a current value of the finger 12 and a teaching data display unit. Reference numeral 62 denotes a current value taken from the robot hand mechanism controller 13 when the operation of the finger 12 is completed.
2n-1 -1 is a point name at which the finger 12 is to operate, and a bit pattern n = 1, 2, 3,.
(In the case of 4 bits). xd, v
d, fd, and xe are a target position, a target speed, a commanded gripping force, and a movement allowable range for the target position, respectively. The above-mentioned xd + xe is stored in the limit position register 23 of FIG.

[0017] The sign f of Point 1 is described as +500, but this is because the method of gripping differs depending on the shape of the work.
When a workpiece such as a cylindrical shape is gripped from the inside, a judgment is made by adding-. Numeral 64 indicates data points that can be taught at the time of teaching operation. 65 is a numeric keypad for directly inputting teaching data, 66 is a key for directly selecting a position component, a speed component, and a gripping force component when performing a teaching operation, 67 is a key used for moving the 64 up, down, left and right, and 68 is each of the taught This is a registration key for confirming data. <Overall Operation> Next, the overall operation of the robot hand mechanism 11, the controller 13 of the robot hand mechanism, the assembly work robot 14, and the controller 15 of the assembly work robot will be described.

First, the robot controller 1 for assembly work
5 operates the assembling robot 14 so that the robot hand mechanism 11 grips a target work.
Next, the assembling controller 15 outputs an operation signal pattern from the input / output interface 17 for actually grasping the target work of the finger 12. FIG. 6 shows this operation signal pattern. In this embodiment, nine patterns are prepared as shown in FIG. As shown in FIG. 6, the configuration of each pattern consists of 4 bits in total, and includes a “start bit” (indicated by a circle with a broken line in FIG. 7) indicating the start of the operation, and a 3-bit operation. It consists of a type bit. In this embodiment, the operation is not started when the start bit is “0”, regardless of the type of the operation type bit. When the start bit is “1”, the operation set by the operation type bit, for example, as shown in FIG.
, The operation indicated by n = 0, 1, 2,... 7 can be executed.

FIG. 7 exemplifies eight kinds of operation commands to the finger. The three operation type bits determine the value of the operation pattern n. Eight operation patterns from n = 0 to n = 7 are set. For example, a pattern with n = 0 indicates an “originating” operation, and an operation with a pattern with n = 1 moves to a position x _d (1) at a speed v _d (1) and then a grip force f _d (1). ). n = 2
The operation up to n = 7 corresponds to the pattern n = 1 and the position x
_d (n), velocity v _d (n), the value of the gripping force f _d (n) is different. Thus, it is a feature of the finger device that the operation can be categorized.

If the present invention is applied to other movable parts of the robot, the number of bits may be further increased. The table of FIG.
It is stored in the RAM 43 in the controller 13. The robot hand mechanism controller 13 inputs the signal pattern from the input / output interface 18 and sets the teaching device 1 in advance.
6 is the same as the signal pattern corresponding to the data such as the target position (x _d ), target speed (v _d ) and target gripping force (f _d ) registered in the teaching data table in the robot hand mechanism controller 13 Is selected, the finger 12 starts the operation indicated by the data, and grips the workpiece.

Next, when the finger 12 actually grips the target work, the robot hand mechanism controller 1
3 outputs a work completion signal to the assembling robot controller 15 from the input / output interface 18, and the assembling controller 15 fetches the completion signal from the input / output interface 17. Is operated to move the gripped work to the target assembling position, and assembled there.

Then, the assembling work controller 15 outputs a signal pattern for releasing the work held by the finger 12 to the robot hand mechanism controller 13 from the input / output interface 17. Then, the signal pattern is input to the input / output interface 18 of the robot hand mechanism controller 13, and the teaching device 16 corresponding to the input signal pattern follows the teaching data registered in the teaching data table of the robot hand mechanism control controller 13 in advance. Then, the operation of the finger 12 is started, and the work is released.

Next, when the opening operation is completed, an operation completion signal is input from the input / output interface 18 of the robot hand mechanism controller 13 to the input / output interface 17 of the assembly work robot controller 15, and the assembly work robot controller 15 The assembling robot 14 is moved to the next same (or different) work with the finger 1.
2 is positioned at a target position for gripping. A series of operations as described above are sequentially repeated. <Control procedure> FIG. 8 shows the robot hand mechanism controller 1.
3 is an overall operation flowchart of FIG.

First, power is turned on (step S1).
Command from the robot controller 15 (N
= 1) (step S2). Here, the operation signal pattern for the robot hand mechanism already transmitted from the assembling robot controller 15 has been input via the input / output interface 18 of the robot hand mechanism controller 13, and when the previous START command is received, The robot hand mechanism controller 13 selects the operation signal pattern from the operation signal patterns of the robot hand mechanism 11 registered on the teaching data table (FIG. 7) of the robot hand mechanism controller 13 and transmits the operation command to the robot hand mechanism controller. 11 to operate the robot hand mechanism 11 (step S3). When this operation is completed, a completion signal is output to the assembling work controller 15, and the current state is maintained until the next robot hand mechanism operation signal pattern is input. In the present embodiment, the operation signal pattern already input after the START command is input is compared with the pattern registered in the teaching data table.
A pattern matching operation may be performed before the RT command is input, and the operation may be executed immediately after the START command is input.

FIG. 9 is a flowchart showing the state of execution of interpretation after the input of the operation signal pattern (N ≠ 0) in step S3 of FIG. In this example,
Since the operations other than the home search operation (n = 0 to n = 7) are operations for opening and closing the grip portion of the finger, the home search operation is executed in step S12, and the operation other than the home search operation (n = 0 to n = 0) is performed. n = 7) from step S14
The processing is executed in step S23.

First, when a signal of the bit pattern of n = 0 (that is, 000) of the input signal pattern is input, the robot hand mechanism 11 moves the finger 12 in the opening direction, and moves the finger 12 to the position of the origin. Lead (step S
11, step S12). Upon completion of the home search operation, an end output is output to the robot hand mechanism controller 13 (step S13).

The operation of finding the origin has already been completed.
When an input signal pattern of n = 1, 2, 3,..., 7 is input, a target position x _d (n) corresponding to the input signal pattern
Is set, and the limit position x _d + x _e is set (step S14). Subsequently, the target speed v _d (n) is set (step S15), and the finger 12 is operated to perform positioning (step S16). See FIG.

Next, in step S17, a commanded gripping force _fd is set. Then, in step S18,
The switching from the target position control loop to the command grip force control loop is performed by the switch 25 in FIG. In step S19, the moving amount of the finger 12 until the finger 12 reaches the target position x command gripping force is set to a predetermined time after being positioned in the _d f _d is a predetermined value are registered in advance x
If it is smaller than _e, it is determined that the target work has been gripped, and a gripping end signal is output in step S20, and switching from the commanded gripping force control loop to the target position control loop is performed in step S23. See FIG.

[0029] As in other cases, the fingers 12 is positioned at the target position, a predetermined value x _e the amount of movement is pre-registered finger 12 to reach the command gripping force f _d
If it is larger than finger 1 in step S21.
It is determined that the current position 2 exceeds a certain value (this is a value such that the finger 12 does not grip the workpiece at all), and in step S22, it is determined that the workpiece is not gripped, and the grip error signal is generated. To switch from the command grip force loop to the command position control loop (step S2).
3). If the current position does not exceed a certain value in step S21, the operation in step S19 is repeated. <Effects of Embodiment> As described above, according to the above embodiment, the robot hand control device includes a plurality of fingers in the robot hand mechanism, teaches finger grip data, and registers the contents. By doing so, it is possible to grasp several different workpieces with fingers by providing a teaching data table of points registered in advance for external ON / OFF input signals. With the device, it is possible to easily register and re-register the target position, target speed, and target gripping data of the finger, release complex programming, reduce errors, and easily control the controller to be controlled. Therefore, there is an effect that the cost can be reduced. <Modifications> The present invention can be variously modified without departing from the spirit thereof.

For example, in the above-described embodiment, the present invention is applied to a finger. However, the field of application of the present invention is not limited to a finger, and any movable part capable of registering an operation command in advance can be used. Anything is applicable. In this case, the movable parts preferably have the same instruction format. In the present invention, the form of the operation instruction is not limited. That is, in the above embodiment, the operation instruction is in a 4-bit format.
The number of bits is not limited. In the present invention, registration of a table is important, but the storage location of the table is not limited.

The present invention may be applied to a system composed of a plurality of devices or an apparatus composed of one device. Needless to say, the present invention can be applied to a case where the present invention is achieved by supplying a program to a system or an apparatus.

[0032]

As described above, according to the present invention,
A method for controlling a movable part of a robot by a robot controller connected to a robot controller for controlling the robot and a teaching device for a movable part of the robot, the movable part controller controlling the operation of a plurality of movable parts of the robot. The operation command code of the movable part of the robot is stored in advance so as to be searchable by a search code corresponding to a desired operation, the search code is received from a robot controller, and the target of the movable part of the robot is inputted numerically to the teaching device. Receiving the position from the teaching device, searching for an operation instruction code corresponding to the search code received from the robot controller, controlling the movable part of the robot based on the search result and the target position received from the teaching device, Displays the current position of the movable part of the robot received from the movable part of the robot.

Therefore, the operation of the robot movable section can be specified by a simple search code. Specifically, for example,
With the teaching device, it is possible to easily register and re-register the target position, target speed and target gripping data of the finger, so that it is free from complicated program work, errors can be reduced, and the controller to be easily controlled can be controlled. Therefore, there is an effect that the cost can be reduced.

[Brief description of the drawings]

FIG. 1 is a diagram illustrating a configuration of a robot system according to an embodiment.

FIG. 2 is a diagram showing a configuration of a finger used in the embodiment.

FIG. 3 is a control block diagram in a hand controller according to the embodiment.

FIG. 4 is a circuit diagram of a hand controller.

FIG. 5 is a panel diagram of a teaching device used in the embodiment.

FIG. 6 is a view for explaining a format of a search code used in the embodiment.

FIG. 7 is a diagram showing a table describing search codes and operations corresponding to the search codes.

FIG. 8 is an overall operation flowchart of the robot hand mechanism controller 13;

FIG. 9 is an operation flowchart of an I / O interpretation execution unit step S3 of the robot controller 13;

FIG. 10 is a view for explaining a gripping operation of a work by a finger.

FIG. 11 is a view for explaining a gripping operation of a work by a finger.

[Description of Signs] 11: Robot hand mechanism, 12: Finger, 13: Robot hand mechanism controller, 14: Robot for assembly work, 15: Robot controller for assembly work, 16 ...
Teaching device, 17, 18 interface, 24 monitor, 25 command switcher, 26 torque amplifier, 27 position counter, 28 servo motor, 29 encoder
41 CPU, 42 ROM, 43 ROM, 44 external I / F

Continuation of the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) G05B 19/18-19/42 B25J 3/00-3/04 B25J 9/10-9/22 B25J 13/00-13 / 08 B25J 19/02-19/06

Claims (7)

(57) [Claims] 1. A robot controller for controlling a robot
Connected to the teaching device of the movable part of the robot
Moving part controller for controlling the operation of the moving part of the robot.
A method of controlling a movable part of a robot by a roller , wherein a plurality of operation instruction codes of the movable part of the robot are provided.
Searchable by search code corresponding to desired operation
A storage step of storing I, to receive the search code from the robot controller
A first communication step, and the robot's robot input numerically into the teaching device.
Second communication for receiving a target position of a moving unit from the teaching device
And a step corresponding to the search code received in the first communication step.
Search for an operation instruction code, and the search result and the second
The robot based on the target position received in the communication step;
Control step of controlling the movable part of the robot, the teaching device, before receiving from the movable part of the robot
A method for controlling a movable part of a robot, comprising displaying a current position of the movable part of the robot. 2. The method according to claim 1 , further comprising the step of:
Receiving a target speed input numerically to the display device, and in the control step, an operation command corresponding to the search code.
Search for the code, the search result, the target position and the
Controlling the moving parts of the robot based on the target speed
The control of the movable part of the robot according to claim 1, wherein
How . 3. The robot according to claim 2 , wherein a movable portion of the robot is the robot.
A finger of a hand, wherein in the second communication step,
Receiving the input target gripping force of the finger from the input device, and, in the control step, an operation instruction corresponding to the search code.
Search for the code, the search result and the target position,
The robot hand based on the target speed and the target gripping force.
And controlling the fingers and fingers.
The control method of the movable part of the robot described in the above . 4. The method according to claim 1, wherein said search code is serial n bits.
This code describes a maximum of 2 ^n-1 actions.
Any of claims 1 to 3, characterized in that
2. The method for controlling a movable part of a robot according to claim 1 . 5. A robot controller for controlling a robot.
Connected to the teaching device of the movable part of the robot
Moving part controller for controlling the operation of the moving part of the robot.
A control device for a movable part of a robot having rollers, wherein a plurality of operation instruction codes of the movable part of the robot are provided.
Searchable by search code corresponding to desired operation
Storage means for storing I, to receive the search code from the robot controller
First communication means, and the robot's robot input numerically into the teaching device.
Second communication for receiving a target position of a moving unit from the teaching device
Means corresponding to the search code received by the first communication means.
Search for an operation instruction code, and the search result and the second
The robot based on the target position received by the communication means;
Control means for controlling a movable part of the robot , wherein the teaching device has a
A control device for a movable part of a robot, wherein a current position of the movable part of the robot is displayed . 6. The teaching device according to claim 6, wherein the second communication unit further includes the teaching unit.
Receiving the target speed entered numerically into the device, The control means includes an operation command code corresponding to the search code.
Search result, the search result, the target position, and the target
Controlling the movable part of the robot based on the speed.
A control device for a movable part of a robot according to claim 5, wherein
Place. 7. The robot according to claim 7, wherein the movable part of the robot is the robot.
Hand fingers, The second communication means further includes a numerical value to the teaching device.
Receiving the input target gripping force of the finger, The control means includes an operation command code corresponding to the search code.
Search result, the search result, the target position, and the target
The robot hand based on the speed and the target gripping force
And controlling the finger and the finger.
Control device of the movable part of the robot.