簡易式中醫把脈儀之設計製作及其訊號分析

Abstract

在已發展了五千年歷史的中醫裡，脈診已被推行了兩千多年，中醫師藉著手指來感覺病人脈搏的強弱、頻率變化以診斷病情。然而脈象的診斷總是倚賴醫師的技術成分以及主觀經驗，因此中醫師的行醫經驗與技術或是手指的靈敏度重大地影響脈診的正確性。所以為了避免誤診第一件事情要做的是脈搏診斷的量化與標準化。 偶然的機會下，我接觸到把脈儀，對於它能夠將中醫理論科學化非常的感興趣。於是，我利用壓電材料當作感應脈搏變化的感測器，自己設計製作了一個簡易式的把脈儀，然後量測自己與同學的寸、關、與尺三脈的脈象。接著，我利用電腦程式將脈象隨時間的振幅訊號即時作傅立葉轉換成頻譜訊號，如此記錄了吃飯前與吃飯後、運動前與運動後、以及生病前與生病後三種對照組共88筆數據。 根據數據分析的結果發現，脈象的振幅訊號經過傅立葉轉換後的頻譜有倍頻關係，這和王唯工博士提出的共振理論相符合。此外，脈象的振幅訊號經過自相關運算後，可以像心電圖儀一樣看出心律不整的程度。

Chinese pulse diagnosis of health has been practiced for more than 2000 years in traditional Chinese medicine. Technically, the diagnosis is applied by a Chinese medical doctor placing his/her fingertips upon a wrist of a patient to feel the amplitude and frequency variations of the patient’s wrist-pulses. Obviously, the accuracy of pulse diagnosis heavily depends on the skill and sensitivity of the doctor, which is rather unreliable. Therefore, the quantification and standardization of wrist-pulse measurement is essential for Chinese medicine modernization. One day, I happened to be diagnosed via a pulsimeter, a wrist-pulse measurement system, and its accuracy surprised me strongly. The experience stimulated me to design and construct a simple pulsimeter as a daily-use health sensor. As a result, we have built one with a commercial piezo and used it for myself and my friends everyday. We always measured the temporal amplitude signals of wrist pulses at three positions, Chon, Gwan and Cheok. The measurement were regularly performed under three conditions: eating, playing, and being sick beforehand and afterward, individually. In total, 88 data were collected and stored into a computer. The temporal signals were transformed into their spectral signals via Fourier transform in a real-time format. Based on the resulting spectrums, the pulse signals can then be analyzed and compared with a contemporary hypothesis, “Theory of Pulse Resonance”, proposed by Dr. Wei-Kung Wang. Accordingly, the health conditions can be diagnosed to some extent. Our study shows the existence of several harmonic frequencies with respect to the basic frequency resulting from heart beating due to the resonance among the beating heart, the artery, and the organs in a human body. This agrees with Wang’s Theory of Resonance. Besides, as a cardiograph, the arrhythmia also can be determined through the auto-correlation operation of the temporary pulse signal.