Interpolation method for robot trajectory planning

Abstract

This paper deals with the problem of interpolation of generated end-effector trajectories for application in robotics. For complex shaped trajectories there are often many high resolution coincident points generated from CAD/CAM systems or trajectory generators. The preprocessing (refining) is necessary for proceeding these points to the manipulator control system. Two interpolation methods are discussed: Line interpolation with polynomial blending and new proposed method Cubic spline interpolation with recalculated feed rate. Second introduced method describes how to interpolate the coincident points and compute the feed rate of the interpolation in order to reduce undesirable peaks in acceleration and ensure demanded position, velocity and acceleration profile along the trajectory. The new interpolation algorithm was implemented to the trajectory generator for complex pipe weld inspection robot. Experimental measurements made on control system of real prototype are finally presented for evaluation of proposed method performance.