JPH05154781A - Multi-axis robot - Google Patents

Abstract

PURPOSE:To mitigate shocks and attain a long life without consuming electric power more than necessary by providing a means applying optimum operating curves to axis actions other than the axis requiring the maximum necessary time. CONSTITUTION:A robot overall controller 9 serves as a main in a robot controller, sub-routines (command reception section 8, state monitor section 10, X- controller 11, Y-controller 12, R-controller 13) are called at a fixed interval, the command reception section receiving the action command responds that the action request is given, and the robot overall controller 9 calculates the operating time of individual axes via an optimum action calculation section 14 and sets the optimum operating curves for individual axes. The optimum operating curves set for individual axes are sent to the robot overall controller 9 then to the X-axis controller 11, Y-axis controller 12, and R-axis controller 13. Control is performed according to the optimum operating curves in these axis controllers, and current values are instructed to an X-axis drive section 15, a Y-axis drive section 16, and an R-axis drive section 17.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a multi-axis robot, and more particularly to a multi-axis simultaneous drive control of a transfer robot.

[0002]

2. Description of the Related Art From the viewpoint of space saving and automation, it is widely used to use an automatic transfer robot having multiple axes. For example, in a device having a storage shelf having addresses in the horizontal direction (X axis) and a vertical direction (Y axis) and an automatic transfer robot that recognizes these addresses and accesses an arbitrary storage shelf. , To ensure high speed when the transfer robot moves to each arbitrary address, X
Axis and Y axis are activated at the same time to perform multi-axis simultaneous drive.
The movement in each axis direction in the conventional library apparatus is controlled according to a predetermined movement curve, and the movement time of each axis depends on the movement distance of each axis. That is, the operation time of each axis for a certain target operation is different.

Regarding the prior art, Japanese Patent Laid-Open No. 58-16730 discloses means for optimally operating a plurality of robots.
No. 7, etc., but there is no particular mention of power saving and long life.

[0004]

The above-mentioned prior art is a very effective means in terms of high speed, but it has the following problems.

Each axis operation module (in the previous example, X axis, Y axis)
In the motion control by (axis), each axis is independent, and the motion according to the fixed motion curve is performed.
That is, a difference in the moving time of each axis causes a difference in the moving time of each axis, and more power than necessary is consumed for an axis that does not require sudden acceleration / deceleration.

Further, by following a fixed operation curve on each axis, shocks and vibrations above a certain level occur on the transfer robot and related parts, and there is a problem such as shortening the life of the transfer robot. .

An object of the present invention is to provide a control method and device for saving power consumption when simultaneously driving each axis.

Another object of the present invention is to provide a control method and apparatus for extending the life of the robot and related parts in a multi-axis simultaneous drive robot.

[0009]

According to the present invention, in regard to multi-axis simultaneous driving of a multi-axis robot, an operation amount in each operation axis direction is obtained from a relationship between an arbitrary target position and a current position of the robot,
Further, the required operation time is obtained from the maximum allowable acceleration (deceleration) degree in each operation axis, the maximum allowable speed and the operation amount. Next, the maximum required time is calculated from the required operation time calculated for each operation axis, and the operation curve is such that the required operation time is the maximum required time for each operation axis other than the indexed operation axis. Is to be reset.

[0010]

With regard to simultaneous driving of the multi-axis robot to arbitrary target positions, by resetting the operation curve in each axis operation module, it is possible to suppress unnecessary power consumption and save labor.

With respect to the operation module to be reset, the robot that holds the acceleration (deceleration) characteristics low is suppressed in impact and the life of the robot is prolonged.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described in detail below.

FIG. 1 is an external view of a robot to which the present invention is applied. The robot is composed of four axes of X-axis, Y-axis, R-axis and Z-axis, and each axis operates to enable access from any position to any position.

FIG. 2 is a diagram showing the entire control system of the robot. The command issued to the device from the CPU 5 is accepted and analyzed by the device control unit 6. The device control unit issues a command to each unit based on the analyzed result. When the robot operation is involved, the device control unit sends the operation command to the robot control unit 7 with position information (target address X, Y,
R) is added and issued.

Within the robot control unit, the entire robot control unit 9 is mainly used, and each subroutine (command receiving unit 8, state monitoring unit 10, X control unit 11, Y control unit 12, R).
The control unit 13) is called at regular intervals, and the command receiving unit that has received the operation command reports to the robot overall control unit that there is an operation request. Upon receiving the motion request, the robot overall control unit calculates the motion time of each axis by the optimum motion calculation unit 14, and sets the optimum motion curve for each axis. The optimum motion curve of each axis set here is sent to the robot overall control 9, and from there, sent to the X-axis control unit 11, the Y-axis control unit 12, and the R-axis control unit 13.
Each axis control unit executes control according to this optimum operation curve, and the X-axis drive unit 15, the Y-axis drive unit 16, the R-axis drive unit 17 are executed.
To indicate the current value, drive the motor on the robot 18, and operate up to each target address.

FIG. 3 shows an outline of the optimum operation calculation section. X,
Based on the relationship between the current position of the Y and R axes and the target position, it is judged whether or not motion is required (19, 21, 23), and if necessary, the maximum acceleration (deceleration) degree, maximum speed, and the like determined in advance for each axis The operation time of each axis is calculated (20, 22, 24) from the positioning time. Next, the maximum required time is calculated from each result (25). Next, with respect to the axes other than the operation axis corresponding to the maximum required time, each operation curve is recalculated based on the maximum required time (26) and the curve is reset, and then returned to the robot overall control unit.

[0017]

In the past, the movement time of each axis was determined because the movement curve of each axis of a multi-axis robot and a transfer robot having multi-axis was from a given position to a given position. Since it depends on the moving distance, unnecessary power is consumed even for an unnecessary axis that suddenly accelerates (decelerates), and at the same time, a certain amount of impact is constantly applied.

According to the present invention, it is possible to achieve a long life and a high reliability by consuming less power than necessary and reducing the impact.

[Brief description of drawings]

FIG. 1 is an external view of a multi-axis transfer robot.

FIG. 2 is an overall view of a robot control system.

FIG. 3 is a flowchart of an optimum operation calculation unit.

[Explanation of symbols]

 8 ... Command accepting section, 9 ... Robot overall control section, 11 ... X control section, 12 ... Y control section, 13 ... R control section, 14 ... Optimal operation calculation section, 20 ... X operation time calculation, 22 ... Y operation Calculation of time, 24 ... Calculation of R operation time, 25 ... Index of maximum required time, 26 ... Reset of operation curve.

Claims (1)

[Claims] 1. A multi-axis robot and a transfer robot having multi-axis, when moving from an arbitrary position to a designated position, when the multi-axes are simultaneously driven, a moving distance in each operation axis direction and each operation. Maximum allowable acceleration (deceleration) on the axis
Degree, allowable maximum speed, and positioning time, a means to know the movement time of each axis, a means to compare the movement time of each axis to know the maximum required time, and an axis other than the axis that requires the maximum required time A multi-axis robot having means for giving an optimum motion curve to a motion.