非线性跟踪微分器在光电编码器测速中的应用  

Application of the nonlinear tracking-differentiator in velocity estimation on optical encoder

作　　者：王帅[1,2] 王建立[1] 陈涛[1] 李洪文[1] 

机构地区：[1]中国科学院长春光学精密机械与物理研究所,吉林长春130033 [2]中国科学院研究生院,北京100039

出　　处：《红外与激光工程》2009年第5期849-853,共5页Infrared and Laser Engineering

基　　金：国家863高科技研究与发展计划项目(2008AA8080202)

摘　　要：给出了一种基于位置测量的实时速度估计方法,并应用于轴角编码器测速。该算法基于非线性跟踪微分器理论,采用对输入信号进行数值积分的方式,快速准确地估计出其微分信号,避免了常规差分算法带来的噪声放大问题;算法不依赖于对象模型,计算量小,易于实现。给出了该算法的理论依据,以及基于欧拉方法的离散表达公式,并进行了数值仿真分析和实验验证。实验结果表明:该方法能有效地降低编码器采样频率和测量噪声对测速的影响,明显提高低速测量的实时性和准确性,进一步将此方法应用于实验系统的速度闭环反馈控制,在不改变控制器参数的情况下,将0.004(°)/s的速度波动方差从1.563(″)/s减少到1.066(″)/s,改善了低速跟踪的速度平稳性。仿真和实验证明了该方法的有效性和实用性。A real-time velocity estimation method based on position measurement was proposed to measure the velocity of axis-angle encoder. Based on the theory of nonlinear tracking-differentiator, the input signal was integrated digitally, and the differential signal was estimated fastly and exactly, avoiding the noise amplification brought by conventional differential method. The method was mode-independent and easily implemented with small computation. The theoretical foundation and discrete time expression using the Euler＇s method were given. The numerical simulation and experimental verification were conducted and applied to telescope. The results show that the influences of sampling frequency and measurement noises on the velocity estimation were reduced, and the measurement accuracy in the low-speed ranges was improved apparently. The approach was also applied to the velocity controller with feedback loop. The standard deviation of 0.004 （°）/s was improved from 1.563 （″）/s to 1.066 （″）/s, which implies that the proposed approach improved the low velocity smooth properties, in the condition of controller parameters were not changed. The simulation and experiment prove the validity and practicability of the method.

关 键 词：非线性跟踪微分器 速度估计 光电编码器 数字速度测量 低速测量 

分 类 号：TH74[机械工程—光学工程]