遥操作的波域预测理论及其应用

Wave prediction theory and application in teleoperation

针对现有的波变量方法不能满足时延条件下医疗正骨系统的需求问题,将预测技术引入波域中,得到系统的稳定性及所需的主从位置跟踪精度.为避免由于从端系统及其模型的初始条件不一致,以及模型失配或者数字舍去误差导致的系统失稳,采用了改进的Sm ith预测器,使用状态估计器与时间前向观测器来预测从端系统的输出,同时使用能量调节算法与预测算法协同工作以确保系统的无源性.一般情况下,基于波变量的预测能保证在变化时延下的稳定性,可是,变化时延或者数字舍去误差都可能导致主从系统之间的位置飘移,因此设计了误差校正器,调节波域能量以达到校正位置飘移的目的.

Aiming at the problem that the present wave variable method can not satisfy the requirement of medical bone-setting in time delay condition, the system stability and the master-slave track precision were obtained by introducing prediction techniques in wave domain. In order to use this method in different initial conditions, and keep it robust in slave model mismatch and round off error, the modified Smith prediction method was used in the scheme. It employed a state observer combined with a time forward observer to estimate the output of slave part, then an energy regulation algorithm was used in the conjuction of a prediction algorithm to ensure the system passivity. The proposed wave prediction method can ensure the system stability under varying time delay environments in most cases, but varying time delay and round off error can lead to the position shift error between master and slave part. Thus an error correction method was designed to regulate the wave domain energy to correct the shift in master-slave position.