An Arterial Compliance Measuring Wristwatch with Flexible Tactile Sensing Dense-Array

This paper reports a wristwatch to measure the arterial compliance (AC) for the first time. A flexible tactile sensing dense-array is integrated in a wireless watch. The dense-array consists of 29 ultra-small pressure sensing chips, enabling high-resolution tactile perception. Because the AC is a property about vascular elasticity and distensibility, the watch senses the pressure distribution on the radial artery, and records the pressure distribution matrixes (PDM) under different external stresses. Subsequently, a deep learning model is employed to fit the regression relationship between the PDM changes and the AC degree, so that the AC would be assessed non-invasively and unobtrusively. Eventually, the root mean squared error (RMSE) and mean absolute error (MAE) of the predicted results reach 0.123 and 0.098 mm<sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup>/kPa, respectively, which are superior to all the previous works.