高频激励下旋转柔性臂逆动力学模态自适应方法研究

在空间柔性机械臂的动力学与控制问题中,逆动力学求解常要求有较高的计算速度.当柔性多体系统受到高频激励时,必须考虑高阶模态才能保证足够的计算精度,但同时提高了计算自由度数,降低了计算速度.为了提高此类问题的计算效率,本文将模态自适应策略应用于旋转柔性臂逆动力学建模,计算了高频激励下产生期望旋转运动的柔性臂关节驱动力矩,验证了该方法的有效性,并研究了重力对计算结果的影响.

Adaptive Mode Method in Inverse Dynamics of a Rotating Flexible Manipulator With High-frequency Excitation

In dynamics and control of space flexible manipulators,high computing speed is always required for solving inverse dynamics.However,when the flexible multibody system suffers from high-frequency excitation such as contact impact,high order modes have to be counted to ensure adequate precisions while the computing speed is lowered down.To increase the computational ef- ficiency of such problems,an adaptive mode method was proposed with an application in inverse dynamic modeling of a rotating flexible manipulator.In the process,the axial displacement caused by transverse deformation of the beam-like model was considered,and high order mode coordinates were reduced gradually as they damped off in the proportion of total energy due to structural damp- ing.The control laws of driving torque for the rotary manipulator articulation were computed to account for its validity.Additionally,the influence of gravity was investigated.