多通道足底壓力穿戴式無線記錄系統

Abstract

隨著社會生活型態改變，健康問題成為備受矚目的焦點，運動也逐漸成為趨勢，規律且適量的活動可以為健康帶來助益，然而不當運動卻可能使身體產生疲勞，甚至傷害。人體進行自主活動時，足底承受整個身體所造成的負載，因此透過足底壓力變化，便可以觀察是否出現異常的壓力分佈和局部高壓。此外，隨著人口急遽老化，年長者及許多神經疾病患者經常出現步態障礙的病症，容易造成跌倒且降低日常生活活動的能力。為了預防運動傷害、觀察老化和神經疾病所帶來的步態問題，日常監測足底壓力成為步態分析之重要條件，因此本研究針對日常活動監測開發一多通道足底壓力穿戴式無線記錄系統，在日常活動中顯示不同位置之足底壓力變化。電路設計使用多工器切換多通道之壓力訊號，縮減整體電路硬體之尺寸大小和功耗，並且使用解多工器得到多通道之壓力訊號，其中使用緩衝電路調整直流電壓準位與控制靜態電流，利用運算放大器設計放大器和低通濾波器，同時，各部分電路配置、元件選擇、足壓量測位置點和感測器數量皆為本論文設計之考量。此外，為提供穿戴式使用，系統設計以輕量和省電為主要考 量，因此採用單電源對系統供電，並設置基線之參考地電位、利用電晶體控制整體系統之靜態電流，使系統可以同時降低重量和功耗，並透過開發板之藍牙實現無線傳輸，在電腦端以 MATLAB 設計簡易使用者介面，提供足底壓力之視覺回饋，為日常活動監測足底壓力和後續分析立下基礎。期望本系統能夠達到日常監測之成效，降低運動傷害的風險，透過進一步進行步態分析後，可以為臨床所用，成為跌倒預測、診斷步態障礙患者病程進展、藥物反應之量化依據，降低老年人和神經疾病患者受傷和就醫的機率，使其維持具有日常生活活動的能力。

With the change in social types, health issues have become the focus of attention, and exercise has become a trend. Regular and moderate activities can bring benefits to health, but improper exercise may cause fatigue and even injury to the body. When the human body performs dailylife activities, the plantar of the feet bear the load of the body weight. Through the pressure changes of the plantar, it is possible to observe whether occurs abnormal pressure distribution or regional high pressure. In addition, with the rapid aging of the population, the elderly and many patients with neurological diseases often suffer from gait disorder, which is prone to falls and reduces the ability to do activities of daily living. To prevent exercise injuries and to observe gait problems caused by aging and neurological diseases, daily monitoring of plantar pressure becomes important for pressure detection and gait analysis. Therefore, this study develops a multi-channel plantar pressure monitoring system for daily activities. A wearable wireless recording system displays the changes in plantar pressure at different positions of the plantar during daily activities. The system uses a multiplexer to input multi-channel pressure signals, and thus reduces the weight of the hardware circuit and power consumption of the amplifier circuit. Subsequently, multi-channel pressure signals were obtained by using a demultiplexer. Among them, the buffer circuit is used to adjust the DC offset voltage and to control the quiescent current, and adequate operational amplifiers were selected to design the amplifier and low-pass filter. Circuit configuration, component selection, measurement location of plantar pressure, and numbers of the pressure sensors are carefully considered during the design phase and are described in detail in this thesis. For wearable purpose, the system design takes lightweight and power saving into consideration. The system is powered by a single battery power, the reference potential is set to around a half of the battery potential, and the quiescent current of the overall system is determined by using discrete transistors. Therefore, the characteristics of lightweight and power saving can be achieved simultaneously. Furthermore, wireless transmission is realized through the Bluetooth of the microcontroller module, and a simple user interface is designed in the MATLAB environment on the computer end to provide visual feedback of the plantar pressures. Then, laying the foundation for daily activity monitoring and subsequent analysis of plantar pressure. It is expected that the developed multi-channel plantar pressure portable wireless transmission system can be used for daily monitoring and reduce the risk of exercise injuries. After further gait analysis, it can be used in clinical applications as a quantitative tool for diagnosing the progression of gait disorders, drug reactions, and even predicting falls. Reducing the chances of injury and medical treatment in the elderly and those with neurological diseases, and maintaining the ability to perform activities of daily living.