大腿肌電訊號用於動作辨識之應用

Toward the Study of the Thigh EMG for the Motion Recognition

陳宗毅(Z. Y. Chen)

指導教授 ： 陳建祥

國立清華大學/工學院/動力機械工程學系/碩士(2007年)

摘要

對老年人及運動傷害者而言，如果有個輔具能辨識出使用者真正的動作意圖且幫助其施力的話，將可以大大的提升他們的生活品質及獨立生活的能力。而肌電訊號是人體肌肉最簡單且最方便取得的訊號。在臨床病理研究中，肌電訊號已廣泛的應用於診斷肌肉性、神經性病變及設計控制義肢的動作等等。因此建構一可攜式的大腿肌電訊號辨識系統，作為主動式下肢輔具的控制命令輸入，為本研究的主要動機。而研究的架構上，將以數位訊號處理器實現整個濾波、特徵值的擷取以輸入類神經網路進行辨識。
本研究的目的，以倒傳遞類神經網路作為肌電訊號辨識系統的主軸，並將之實現在數位訊號處理器中。研究中，先以Matlab軟體作為軟體程式驗證的環境。首先，將由肌電訊號擷取與放大電路所取得之大腿肌電訊號經由小波轉換，取得所需的頻帶後，透過基本特徵值萃取處理，接著送進類神經網路做實際應用的模擬與測試。以軟體印證其可行性之後，將整個流程撰寫於數位控制處理器中進行辨識，以利將來實際用於下肢輔具的控制。

關鍵字

肌電訊號 ； 辨識 ； 類神經網路 ； 自我回歸模型 ； 小波轉換

並列摘要

Supposed that there is an instrument that could identify a user's true intention to move and assist in exerting forces, it would substantially improve the quality of life and independence of the elderly and injured. The electromyogram(EMG) is that the simplest and the most convenient electrical signals that can be acquired from human muscle. On the other hand, the electromyogram(EMG) is used extensively on diagnosing muscular or nerve pathological disorder. Additionally, EMG is also used in control of prosthesis. Therefore, the objection of this study is to build up a portable EMG identification system to be the input command of an actively lower limbs prosthesis.
In this study, an artificial back-propagation neural network for EMG identification is realized on a Digital Signal Processor(DSP). First, a Matlab program is developed to test the feasibility of the software. In the beginning, the EMG would be collected by the signal-conditioning circuit. Then, a wavelet transformation was applied to preserve the desired frequency band but filtered out the others. After the basic feature attraction, the signals would be sent into an artificial neural network to proceed the simulation. Finally, the complete algorithm would be realized on a DSP chip.

並列關鍵字

EMG ； Recognition ； Artificial Neural Network ； Auto-regression ； wavelet

參考文獻

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