ABSTRACT
This chapter presents the bladder-type sensors which readily conform to the curvature of human soft tissue and the support media, have good repeatability in the measurements, are inherently insensitive to shear forces and temperature changes and thus they are widely used in the measurement of pressure at the skin-cushion interface. An ideal sensor system would not perturb any parameters at the body/support interfaces but measure the true interface pressures. During a test, the air bladder is placed at the skin-cushion interface. Before inflation, the electrical contacts in the bladder touch each other and thus close the circuit as monitored by the indicator. Then the inflation device pumps in the air, and the pressure in the bladder increases. A microprocessor-based switch scanner/pressure monitor can be designed to interface the type pad with a personal computer so that the operation of the system is quick and easy.
