探討編織氣動致動器於膝部施力對上樓梯之影響

Abstract

本研究旨在開發一款應用於膝關節的輕量化穿戴式氣動輔助裝置，藉由針織氣動人工肌肉（knit-covered pneumatic artificial muscle, k-PAM）於上樓梯過程中提供膝關節伸展輔助力矩，以降低肌肉激發需求。為達成此研究目標，本裝置設計滿足三項關鍵需求：採用氣動人工肌肉確保柔軟性與輕量化特性、整合力敏電阻感測器實現主動式輔助功能，以及建立精準時序控制機制於站立期初期提供膝關節伸展輔助。 裝置整合壓力感測器與即時步態識別控制策略，能在站立期初期提供輔助力。透過十位健康受試者之人體實驗，分析穿戴裝置對關節角度與肌電訊號的影響。結果顯示，在輔助啟動條件下，16條肌肉中股直肌、臀大肌與腓腸肌群等關鍵肌肉於站立期與完整週期皆呈現激發顯著性下降（p<0.05），表示裝置有效分擔膝關節周圍肌群的伸展需求。關節角度分析方面，膝關節活動範圍微幅上升，踝關節變化達統計顯著，顯示下肢運動鏈的協調調整效應。值得注意的是，由於關節角度變化大部分未達統計顯著性差異，表明輔助裝置基本不影響使用者原有的運動方式和關節角度模式，此特性有助於維持自然的運動協調性並降低適應負擔。 本研究成功驗證針織氣動人工肌肉輔助裝置在減輕膝關節負荷方面的有效性。該系統具備柔軟性、輕量化、安全性等優勢，能在提供有效輔助的同時維持使用者自然運動模式，展現良好的實用潛力與臨床應用價值。

This study aims to develop a lightweight wearable pneumatic assistive device for the knee joint. The device utilizes knit-covered pneumatic artificial muscles (k-PAMs) to provide extension assistive torque to the knee during stair ascent, thereby reducing the demand for muscle activation. To achieve this goal, the device is designed to meet three key requirements: employing pneumatic artificial muscles to ensure softness and lightweight characteristics; integrating Force Sensor Resistors (FSRs) to enable active assistance; and establishing a precise timing control mechanism to deliver knee extension support at the early stance phase. The device integrates pressure sensors and a real-time gait recognition control strategy, enabling it to provide assistance during the early stance phase. Human experiments were conducted with ten healthy participants to analyze the effects of the wearable device on joint angles and electromyography (EMG) signals. The results showed that, under assistive conditions, key muscles such as the rectus femoris, gluteus maximus, and gastrocnemius exhibited significantly reduced activation (p< 0.05) during the stance phase and across the full gait cycle. This indicates that the device effectively reduces the extension demand on muscles surrounding the knee joint. In terms of joint kinematics, the knee's range of motion showed a slight increase, while ankle joint changes reached statistical significance, suggesting a coordinated adjustment in the lower limb kinematic chain. Notably, since most joint angle variations did not reach statistical significance, it suggests that the assistive device does not substantially alter the user’s original movement patterns or joint angle trajectories—this feature helps maintain natural movement coordination and minimizes adaptation burden. This study successfully demonstrates the effectiveness of the knit-covered pneumatic artificial muscle assistive device in reducing knee joint load. The system offers advantages such as flexibility, lightweight design, and safety, enabling it to provide effective assistance while preserving the user’s natural gait pattern. These attributes highlight the device’s strong practical potential and clinical application value.