Optimized Continuous Trajectory Look-ahead Algorithm with Comprehensive Multi-constraints

doi:10.3901/JME.2019.13.151

Abstract

Abstract: During machining process with existing continuous trajectory interpolation algorithms, normal acceleration and trajectory error exceed maximum result in low machining efficiency and machining precision. Therefore, a continuous trajectory look-ahead interpolation algorithm is proposed, which based on comprehensive multi-constraints and look-ahead technique. The algorithm limits the maximum feed rate of arc machining by restricting the chord error and the normal acceleration. The optimal link feedrate between the trajectory segments is calculated according to the constraints of the integrated motion vector relationship, system dynamics performance and the trajectory segment length. Smoothness of the link feedrate between trajectory segments is ensured, according to the speed look-ahead control and the asymmetric S-curve acceleration/deceleration control. The experiment results show that the normal acceleration and the trajectory error output by proposed look-ahead interpolation algorithm do not exceed allowable maximum of the system, and the synthesized reference velocity transits smoothly, and the kinematic axis velocity will not mutate, and the maximum trajectory error of the interpolation output is less than the maximum allowed chord error in the whole range. This algorithm can improve machining smoothness and machining accuracy while machining efficiency is ensured.

Key words: asymmetric S-curve, continuous trajectory planning, linked federate, look-ahead interpolation

CLC Number:

TP273

CHEN Lin, HUANG Xufeng, LIU Meng, YUAN Shanshan, HE Feixiang, YI Jian, PAN Haihong. Optimized Continuous Trajectory Look-ahead Algorithm with Comprehensive Multi-constraints[J]. Journal of Mechanical Engineering, 2019, 55(13): 151-159.

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