Development and Testing of a Prototype for 3D Radial Pulse Image Measurement and Compatible With 1D Pulse Wave Analysis

This study proposes the prototype of a wrist pulse acquisition device with three-dimensional pulse image (3DPI) obtained at the radial artery. The proposed prototype is designed with mechanical and electronic circuit hardware as well as the control and data acquisition software to have fourteen degrees of movement freedom against the sophisticated geometry of the wrist radial artery for accurate pulse-taking. Three robot fingers with nine degrees of movement freedom and a wrist fixer with two degrees of rotation freedom and one degree of manual movement freedom are designed to mimic the fine pulse-taking skill of a Chinese medicine physician. The customer-designed array sensors with $5\times5$ -1 sensing elements in an array are attached on the robot fingertips to get 3DPI with spatial information for direct translation of pulse feeling patterns in Chinese medicine texts, in addition to being compatible with 1D pulse wave analysis. To check reliability of the prototype, adopted is SphygmoCor with pulse data correlation. Consequently, the prototype passes safety tests and has high correlation of pulse data (waveform and peripheral augmented index) with those obtained by SphygmoCor. The automatic multi-depth pulse-taking with robot fingers attached array sensors on their tips can get acceptably repeatable pulse data with coefficient of variation less than 10%. By simultaneous pulse-taking at Cun-Guan-Chi positions, 3DPIs demonstrate great different stereoscopic waveshapes against almost unchanged single temporal pulse waveshape. Hence, the proposed prototype may be a useful tool to perform array pulse-taking for Chinese medicine pulse diagnosis and pulse wave analysis for cardiovascular examination.