A Two-Step Readout Technique for Large-Array Resistive Sensors

Large-array resistive sensors have nowadays found various applications in a variety of medical and industrial systems. In this paper, a two-step readout procedure is proposed, which increases the average speed of the readout for the input patterns, located in an area much smaller than the entire array. In the proposed method, during the first step, only a spatially coarse scan is performed where the location of the input is roughly estimated. Then, during the second step, the values of the resistors are accurately measured, just within the allocated area. Measurement results of a 52 × 44 resistive array used in a plantar pressure scanner show that the average readout time for a gait pattern is reduced from 23 ms for the conventional circuit to 5.7 ms using the proposed technique.