A Predictive Model for Force-Sensing Resistor Nonlinearity for Pressure Measurement in a Wearable Wireless Sensor Patch

Implementation of a Pressure Ulcer Prevention System would prevent pressure ulcers, ease workload on caregivers, enabling patient treatment and monitoring outside a hospital setting, and reduce health care costs. Accurate measurement of pressure is an important criteria in order to achieve the above said goals. A challenge associated with using Force-Sensing Resistors (FSRs) as a pressure sensor is the part-to-part variability of up to +/- 25%. This paper presents a novel modeling technique for correcting force sensor nonidealities, without requirement of prior knowledge of material parameters, and enabling measurement accuracies of +/- 2% over a pressure range of 1N to 5N.