Track planning and control method of free curve of industrial robot based on double quaternions

Abstract

The invention discloses a track planning and control method of a free curve of an industrial robot based on double quaternions. Control point data of the Cartesian space are adopted for describing the contour of the space free curve, and meanwhile an Adams differential equation is adopted for NURBS interpolation compacting calculation, and interpolation speed is adjusted in a self-adaption manner with the maximum contour error and maximum acceleration as constraint conditions; and then the position and posture of the robot in the Cartesian space are converted to a four-dimensional space through a short linear segment obtained through interpolation by adopting the double quaternions, the motion trail of the robot is subjected to spherical linear interpolation through hyperspherical rotation, and finally the track of the NURBS free curve of the industrial robot is planned.

Description

technical field [0001] The invention relates to a trajectory planning control method of an industrial robot free curve based on a double quaternion, and belongs to the technical field of robot trajectory planning. Background technique [0002] Modern manufacturing has higher and higher requirements for robot performance, and the trajectory planning algorithm of the robot in the task space occupies an important position in the robot control system, which directly affects the performance and efficiency of the robot's end motion. Moreover, in robot motion control, the basic straight line and arc trajectory curves can no longer meet the application requirements of industrial processing, and the commonly used B-spline curves, Bézier curves, and Clothoid curves cannot be described with an accurate and unified representation method. curves and free curves. [0003] Usually, the expected trajectory of the robot is given a series of Cartesian or joint space points in advance, and th...

AI Technical Summary

Problems solved by technology

Moreover, in robot motion control, the basic straight line and arc trajectory curves can no longer meet the application requirements of industrial processing, and the commonly used B-spline curves, Bézier curves, and Clothoid curves cannot be described with an accurate and unified representation method. Curves and Free Curves

[0003] Usually, the expected trajectory of the robot is given a series of Cartesian or joint space points in advance, and the speed passing through the point or the time between two points is given, and the maximum speed allowed by the robot movement is also limited, and then respectively Realize the position trajectory planning and attitude trajectory planning of the robot end effector, while the attitude trajectory planning of industrial robots usually uses the Euler angle method and the equivalent axis method to interpolate the attitude, but the Euler angle has the defect of universal deadlock, etc. There is a problem that the effective axis method cannot determine the rotation axis when the rotation amount is 0

Although using the quaternion method can solve the above-mentioned problems of robot attitude trajectory interpolation, other interpolation algorithms need to be used for trajectory position interpolation, which has a large amount of calculation and affects the real-time requirements of the control system for trajectory planning.

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