由於中風患者患病後，其身體機能損傷會影響日常生活的動作與生活品質。對於下肢不對襯的功能，會造成病患難以產生連續性與順暢的交替動作，例如走路或是騎腳踏車。近來，為了增強患者所殘餘的部分動作，利用電刺激器結合腳踏車運動已被用來做為復健技術。在電刺激過程中，造成有殘存肌力患者之肌肉動作包含兩種來
源：一是自主性的收縮，另一是由電刺激引發的收縮。此肌肉動作型態即為混合式肌肉運動。本研究的目的是發展一套肌電訊號量測系統，在動態下做功能性電刺激治療時，能夠抑制電刺激造成的干擾，並且藉由訊號處理方式，能夠分離出自主性以及電刺激所產生的肌電訊號系統。所分離出的電刺激所激發的肌電訊號與自主性收縮產生的肌電訊號可分別表是為中風病患由電刺激所引發的力量以及患者殘存動作能力。此外，我們也設計峰對峰值偵測電路用於即時量測由電刺激所誘發肌電訊號的峰對峰值。在初步結果顯示利用訊號處理方式，將未含電刺激干擾之混合肌電訊號分離出自主性與誘發性肌電訊號。在動態下，峰對峰偵測電路可以正確與靈敏地捕捉到誘發性肌電訊號的峰對峰值。此資訊的獲得，對於在混合式肌肉觸發模式下的功能性電刺激腳踏車系統可作為控制規則。這將有助於未來與肢體缺陷相關的研究，包括了中風、未完全脊髓損傷患者以及有著自主動作功能變異之正常老年人。

Those surviving strokes may be left with physical impairments deeply affecting the
activities of daily living and quality of life. Patients with asymmetrical lower limb
functions are difficult to perform continuous and smooth reciprocal movements in the
lower limb, such as walking and cycling. To enhance residual functions of patients with
partial motor disorders, electrical stimulation (ES) combined with cycling exercise has
been utilized as a rehabilitation technology recently. For the limb with residual function,
during stimulating, muscle contraction is generated from two different excitation sources:
volitional and external electrical stimulation. This muscle activation is referred as hybrid
muscle activation. The aim of this study is to develop an EMG recording system, which
includes the stimulus artifact suppressor and software and hardware implementation for
extracting volitional and ES-induced EMG signals in dynamic movement during functional
electrical therapy (FET). The separation of electrically evoked EMG and EMG interference
can represent the force induced by the electrical stimulation and residual movement ability
of the stroke subject. In addition, we design Peak-to-Peak (PTP) detector for real-time
measurement of PTP amplitude of ES-induced EMG. Our pilot results show that signal
processing can separate volitional and stimulus EMG from artifact-free overall EMG. The
PTP detector can accurately and sensitively capture PTP value of stimulus-induced EMG during dynamic movement. The information acquired can serve as a training protocol or a
control strategy for an FES-cycling induced by hybrid muscle activation in future study which therefore would benefit wide ranges of physically handicapped including stroke, incomplete SCI, and able-bodied elderly with varied volitional muscle functions.

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