Error Signal Processing in Iterative Learning Control

• Main Authors: Lo Yin Lung, 羅印隆
• Other Authors: Chen, Shyh-Leh
• Format: Others
• Language: zh-TW
• Published: 2012
• Online Access: http://ndltd.ncl.edu.tw/handle/04409292328480937863

碩士 === 國立中正大學 === 機械工程學系暨研究所 === 100 === This study analyzes effects of error signal using different signal processes. Some complex signal processes may have better effects and some simple ones have effects which are not so good but achieve specifications,too. This study shows the statistics results, so that we can choose the best error signal process in iterative learning controling. Command-based iterative learning is a kind of controling law used in periodic and iterative tapping. It changes the next command by dealing with the previous error with the learing algorithm, and we can make error smaller and smaller in this iterative learning way. But different signal processes will make different learning effects, so this study divides common error signal processes into two parts. The first one is performance improvement for iterative learning control and the other one is filters(wavelet transform,first order low pass filter,moving average,empirical mode decomposition) .We apply these two parts in iterative learning controling for a rigid tapping system and summarize what demand makes the best effect of error convergence in different speed feeding situations. The experiment results show that, we can reduce synchronous errors by 17 times with the spindle speed of 1000 rpm , 58 times with the spndle speed of 6000 rpm. The effect is pretty significant with high-speed feeding. The main contributions of this study are: 1. We integrate suitable filters and performance improvement for iterative learning control to make iterative learning control results more accurate. 2. We summarize the way to choose the proper error signal process in different demands of accuracy and speed.