JPH06114764A - Controller for robot - Google Patents

Abstract

PURPOSE:To simplify the designation of a speed when a speed pattern during movement of a robot is properly varied according to work application and the using condition of the robot. CONSTITUTION:Through input of present position information and moving objective position information, interpolation between a present position and a movement objective position is effected to execute movement. A plurality of kinds of patterns 11a, 11b,... 11n during interpolation between the present position and the movement objective position are provided. A speed command isswing part 6 to issue a speed command through selection of a plurality of kinds of the patterns 11a, 11b,...11n, and a position command issuing part 7 to compurte the position command of a robot R from the speed command are provided.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a robot controller, and more particularly to a robot controller capable of arbitrarily selecting and setting a speed pattern for calculating an operation speed command of the robot.

[0002]

2. Description of the Related Art An example of a conventional robot controller is shown in FIG.
Shown in. In the figure, 1 is a program storage unit for storing a program configured by a user and position variable data generated by teaching or manual data input, and 2 is an instruction decoding unit for decoding the instructions of the program read from the program storage unit 1. Reference numeral 3 is a target position generator that generates a position variable Pd representing the target position when the decoded command is a command relating to a movement operation. The target position Pd differs depending on the type of movement command. For example, in the case of a movement command of linear interpolation operation, the coordinates of the hand of the robot R (x, y, z) and the posture of the hand of the robot R (α, β,
γ). There are various other cases, such as the case where the joint angles (θ1, θ2, θ3, θ4, θ5, θ6) of each axis of the robot R are expressed. y, z, α, β, γ) coordinate values.

Reference numeral 54 is a position control means, which generates a variation amount Vi of each component of the coordinate value at every Δt time based on the speed pattern information 55 and at every Δt time based on the speed command Vi. And a position command generator 7 for generating a position command Pi. 8 is position control means 5
A coordinate conversion unit that converts the position command Pi generated by 4 into the drive motor pulse number Ji of each axis of the robot R, and 9 is a positioning control unit that positions each axis of the robot R based on the drive motor pulse number Ji. .

An acceleration / deceleration time changing unit 60 changes the acceleration / deceleration time of the speed pattern information 55 when the instruction decoded by the instruction decoding unit 2 is an acceleration / deceleration time changing command.

FIG. 7 shows an example of a program stored in the program storage unit 1. Reference numeral 41 is a command for instructing to move to the target position P1 by linear interpolation, and 42 is a command for changing the acceleration time of the speed pattern during movement to a designated time. 43 is a command for instructing to move to the target position P2 by linear interpolation, like the command 41.

Next, the operation will be described. When one of the programs stored in the program storage unit 1 is selected to be executed, the instruction decoding unit 2 starts decoding the instruction in the program. When the information obtained by decoding the command is a command related to the movement of the robot R (eg, 41 in FIG. 7), the command decoding unit 2 commands the target position generating unit 3 to generate the target position Pd. To do. By this command, the target position generator 3
Produces a target position Pd.

Speed pattern information 55 of the position control means 54
Is the maximum speed Vma as shown in the speed pattern explanatory diagram of FIG.
It is a predetermined speed pattern determined by a plurality of parameters such as x, acceleration time ta, deceleration time td, and time constant ts for slowing changes in acceleration. The speed command generator 6 of the position control means 54 controls the speed and the trajectory of the robot R based on the target position Pd, the previous speed Vi-1, the previous position Pi-1, and the speed pattern information 55. The position command generator 7 performs position control.

The speed control and the position control are performed by sampling control. That is, the following processing is performed at every constant time Δt to generate the speed command Vi and the position command Pi. The speed command Vi referred to here is the amount to be moved in Δt time. When the previous speed (before Δt) Vi-1, the target position Pd, the previous position Pi-1 and the predetermined speed pattern information 55 are input, the speed command generation unit 6
First, the moving amount ΔP = Pd−Pi−1 of each coordinate value is obtained from the target position Pd and the previous position command Pi−1, the direction of Vi is determined in the same direction as this vector, and the previous speed Vi−1 is determined. Then, the magnitude of the current speed Vi is determined from the speed pattern information 55 and the movement residual ΔP which are predetermined. Vi
Is given by Vi = (Δx, Δy, Δz, Δα, Δβ, Δγ). Further, the position command generator 7 generates the current position Pi from the current speed Vi given by the speed command generator 6 and the previous position Pi-1, based on the formula Pi = Pi-1 + Vi.

When the moving position Pi of this time is determined, the coordinate conversion unit 8 uses the robot R from (x, y, z, α, β, γ).
To each joint axis angle (θ1, θ2, θ3, θ4, θ5, θ6), and the number of motor drive pulse Ji for each axis of the robot R Ji
To the positioning control unit 9. Positioning control unit 9
Is the D / A that contains the drive motor pulse number Ji for each axis
It outputs to the motor of each axis of the robot R via the converter.
As a result, the robot R moves to the position of the position command Pi.

If the information obtained by the instruction decoding unit 2 decoding the instruction is an instruction relating to the acceleration / deceleration time change of the speed pattern (for example, 42 in FIG. 7), the instruction decoding unit 2
Instructs the acceleration / deceleration time changing unit 60 to change the acceleration / deceleration time of the speed pattern information 55, and the acceleration / deceleration time changing unit 6
0 changes ta or td in FIG. 5 to a designated time. Next, when the information obtained by the instruction decoding unit 2 by decoding the instruction is an instruction related to the movement operation of the robot R (for example, 4 in FIG. 7).
In 3), the instruction decoding unit 2 is the destination position generating unit 3 similarly to the above.
To the target position Pd. Hereinafter, in order to move in the same manner as described above, it is necessary not only to change the acceleration time in the above example, but also to make detailed settings by a plurality of commands such as changing the deceleration time.

[0011]

Since the conventional robot controller is constructed as described above, in order to appropriately change the speed pattern when the robot moves, each speed pattern is formed. It is complicated because the parameters must be set in detail. In addition, it is not easy because there is no simple method to set the optimum value under the condition that the vibration of the robot is suppressed and the moving time is shortened as much as possible.

The present invention has been made to solve the above problems, and an object of the present invention is to obtain a robot control device capable of easily selecting a speed pattern from operating conditions.

[0013]

A robot controller according to a first aspect of the present invention has a plurality of types of speed patterns when interpolating between a current position and a movement target position, and selects the plurality of types of speed patterns. And a position command generation unit that calculates a position command of the robot from the speed command.

A robot controller according to a second aspect of the present invention is the robot controller according to the first aspect of the present invention, in which each of a plurality of velocity patterns is adjusted by a parameter or a velocity is newly added. It is provided with a pattern definition section.

[0015]

In the first aspect of the present invention, a designated speed pattern is selected from a plurality of preset speed patterns and used as the speed pattern during movement. The plurality of speed patterns are determined based on the work use and use conditions of the robot, and therefore, by specifying the work use or use conditions of the robot, it is possible to select a speed pattern suitable for them.

According to the second aspect of the present invention, each of the plurality of speed patterns can be adjusted by parameters or a speed pattern for newly adding can be defined to more finely set the speed pattern during movement.

[0017]

【Example】

Example 1. An embodiment of the first invention will be described with reference to FIGS. In the figure, the same reference numerals as those in the conventional example indicate the same as or equivalent to those in the conventional example.

FIG. 1 is a block diagram showing the configuration of a robot controller. In FIG. 1, 4 is a position control means, which has a plurality of preset speed patterns 11a, 1a.
Speed pattern information 5 selected from 1b, ... 11n
The speed command generator 6 generates a change amount Vi of each component of the coordinate value at every Δt time, and the position command generator 7 generates a position command Pi at every Δt time based on the speed command Vi. Further, 10 is a speed pattern selection unit, which changes the speed pattern of the speed pattern information 5 to a specified speed pattern when the command decoded by the command decoding unit 2 is a speed pattern selection command.

FIG. 2 shows an example of a program stored in the program storage unit 1. Reference numeral 21 is a command for instructing to move to the target position P1 by linear interpolation, and 22 is a command for changing the moving speed pattern to a designated pattern.
Reference numeral 23 is a command for instructing to move to the target position P2 by linear interpolation like 21.

Next, the operation will be described. In FIG. 1, when a program among a plurality of programs stored in the program storage unit 1 is selected to be executed, the instruction decoding unit 2 starts decoding the instruction in the program. The information obtained by decoding the command is the robot R
If the command is for the movement operation of
In 1), the command decoding unit 2 instructs the target position generating unit 3 to generate the target position Pd. With this command, the target position generator 3 generates the target position Pd.

The speed pattern information 5 of the position control means 4 is the maximum speed Vmax as shown in the speed pattern explanatory diagram of FIG.
Or a predetermined speed pattern determined by the acceleration time ta, the deceleration time td, the time constant ts for slowing the change in acceleration, and the like. The speed command generator 6 of the position control means 4 controls the speed and the trajectory of the robot R based on the target position Pd, the previous speed Vi-1, the previous position Pi-1 and the speed pattern information 5. The position command generator 7 performs position control.

The speed control and the position control are performed by sampling control. That is, the following processing is performed at every constant time Δt to generate the speed command Vi and the position command Pi. When the previous speed (before Δt) Vi−1, the target position Pd, the previous position Pi−1, and the predetermined speed pattern information 5 are input, the speed command generator 6 first determines the target position Pd and the target position Pd. The movement amount ΔP = Pd−Pi−1 of each coordinate value is obtained from the previous position command Pi−1, and V is moved in the same direction as this vector.
The direction of i is determined, and the magnitude of the current speed Vi is determined from the previous speed Vi-1 and the predetermined speed pattern information 5 and the movement residual ΔP. Vi is Vi = (Δx,
Δy, Δz, Δα, Δβ, Δγ). Also,
The position command generator 7 calculates the formula Pi = Pi-1 + Vi from the current speed Vi given by the speed command generator 6 and the previous position Pi-1.
Based on this, the current position Pi is generated.

When the moving position Pi of this time is determined, the coordinate conversion unit 8 calculates the robot R from (x, y, z, α, β, γ).
To each joint axis angle (θ1, θ2, θ3, θ4, θ5, θ6), and the number of motor drive pulse Ji for each axis of the robot R Ji
To the positioning control unit 9. Positioning control unit 9
Is the D / A that contains the drive motor pulse number Ji for each axis
It outputs to the motor of each axis of the robot R via the converter.
As a result, the robot R moves to the position of the position command Pi.

When the information obtained by the instruction decoding unit 2 by decoding the instruction is the instruction relating to the speed pattern change (for example, 22 in FIG. 2), the instruction decoding unit 2 causes the speed pattern change unit 1 to operate.
0, an instruction to change the speed pattern of the speed pattern information 5 is issued, and the speed pattern selection unit 10 selects a specified speed pattern from preset speed patterns 11a, 11b, ... Change information 5. In the example of 22 of FIG. 2, the speed patterns 11a and 11
The first (11a) is selected from b, ..., 11n. Next, when the information obtained by the instruction decoding unit 2 by decoding the instruction is an instruction related to the movement operation of the robot R (for example, 2 in FIG. 2).
In 3), the instruction decoding unit 2 is the destination position generating unit 3 similarly to the above.
To the target position Pd. The movement thereafter is the same as the above, but the speed pattern information 5 at the time of movement is the pattern changed at 22 in FIG.

The command shown as an example in 22 of FIG. 2 is a number behind the command, for example, 1 is a standard operation, 2 is for transportation (a large operating distance and a short moving time), and 3 is a positioning priority operation. By setting such as (the movement time of each axis of the robot is small even if the movement time is slightly longer) and registering the speed pattern that matches each condition, you can freely set the speed pattern according to the work. You will be able to set it.

Example 2. An embodiment of the second invention will be described with reference to FIGS. In the second embodiment, a plurality of speed patterns according to the first invention can be arbitrarily set. FIG. 3 is a block diagram showing the configuration of the control device of the robot. In FIG. 3, 4 is a position control means, which has a plurality of preset speed patterns 11a,
11b, ... 11n based on the speed pattern information 5 selected, a speed command generator 6 for generating a variation amount Vi of each component of the coordinate value at each Δt time and a position at each Δt time based on the speed command Vi. The position command generator 7 generates a command Pi. Reference numeral 10 denotes a speed pattern selection unit, which changes the speed pattern of the speed pattern information 5 to a specified speed pattern when the command decoded by the command decoding unit 2 is a speed pattern selection command. 12 is 11a,
11b, ... 11n is a speed pattern defining section for defining each of the speed patterns, and when the instruction decoded by the instruction decoding section 2 is a speed pattern defining instruction, the speed patterns 11a, 11b ,. ..Change or additionally define the applicable speed pattern of 11n.

FIG. 4 shows an example of a program stored in the program storage unit 1. Reference numeral 31 is an instruction to move to the target position P1 by linear interpolation, 32 is an instruction to define a predetermined speed pattern, and 33 is an instruction to change the moving speed pattern to a specified pattern. 34 is 31
Is a command for instructing to move to the target position P2 by linear interpolation.

Next, the operation will be described. In FIG. 3, when a certain program among the plurality of programs stored in the program storage unit 1 is selected to be executed, the instruction decoding unit 2 starts decoding the instruction in the program. The information obtained by decoding the command is the robot R
If the command is for the movement operation of
In 1), the command decoding unit 2 instructs the target position generating unit 3 to generate the target position Pd. Hereinafter, the operation of the robot R is the same as that of the first embodiment, and therefore will be omitted.

When the information obtained by the instruction decoding unit 2 by decoding the instruction is the instruction related to the speed pattern definition (for example, 32 in FIG. 4), the instruction decoding unit 2 determines the speed pattern definition unit 1
2 is instructed to define (change or additionally define) the corresponding speed pattern among the speed patterns 11a, 11b, ... 11n, and the speed pattern defining unit 12 changes or additionally defines the corresponding speed pattern. In the example of 32 of FIG. 4, ta of the first speed pattern (11a),
Change tb and ts to specified values. When the information obtained by the instruction decoding unit 2 by decoding the instruction is the instruction regarding the speed pattern change (for example, 33 in FIG. 4), the instruction decoding unit 2 causes the speed pattern selecting unit 10 to send the speed pattern of the speed pattern information 5. And the speed pattern selection unit 10 causes the speed patterns 11a and 11 set in advance to be changed.
The designated speed pattern is selected from b, ..., 11n and the speed pattern information 5 is changed. Next, when the information obtained by the instruction decoding unit 2 by decoding the instruction is the instruction related to the movement movement of the robot R (for example, 34 in FIG. 4), the instruction decoding unit 2 instructs the target position generating unit 3 in the same manner as described above. Destination position Pd
Command to occur. The subsequent movement is the same as the above, but the speed pattern information 5 at the time of movement is 2 in FIG.
The pattern is changed in 2 and 23.

By using the commands shown as examples in 22 and 23 of FIG. 4, it becomes easy to set and select the speed pattern in accordance with the working purpose and conditions.

[0031]

As described above, according to the first aspect of the invention, there are a plurality of types of speed patterns, and each of these speed patterns is set in advance in accordance with the working application and use condition of the robot. When operating, the optimum speed pattern can be easily set simply by designating the operating conditions, and the conventional complexity of setting each parameter forming the speed pattern in detail is released.

Further, according to the second invention, the speed pattern defining section for defining each of the plurality of speed patterns makes it possible to set a finer speed pattern while maintaining the simplicity.

[Brief description of drawings]

FIG. 1 is a block diagram showing speed and position control of a robot controller according to an embodiment of the present invention.

FIG. 2 is a diagram showing an example of a program stored in a program storage unit.

FIG. 3 is a block diagram showing speed and position control of a robot controller according to another embodiment of the present invention.

FIG. 4 is a diagram showing an example of a program stored in a program storage unit.

FIG. 5 is a speed pattern explanatory diagram.

FIG. 6 is a diagram showing an example of a conventional robot controller.

FIG. 7 is a diagram showing an example of a program stored in a program storage unit.

[Explanation of symbols]

 1 Program Storage Section 2 Command Decoding Section 3 Target Position Generation Section 4 Position Control Means 5 Speed Pattern Information 6 Speed Command Generation Section 7 Position Command Generation Section

Claims (2)

[Claims] 1. A robot controller that moves by interpolating between the current position and the moving target position by inputting the current position information and the moving target position information, when interpolating between the current position and the moving target position. A robot having a plurality of speed patterns and including a speed command generation unit that selects the plurality of kinds of speed patterns to generate a speed command and a position command generation unit that calculates a position command of the robot from the speed command Control device. 2. The control device for a robot according to claim 1, further comprising a speed pattern defining unit for adjusting each of the plurality of speed patterns with a parameter or newly adding the speed pattern.