Abstract: A control for use with pressure-sensitive devices, such as in a machine-guarding application. A plurality of pressure-sensitive devices, such as pressure-sensitive safety mats, are operatively connected to produce a disable signal and a status signal. An activation module produces a switching output responsive to the disable signal and the status signal to disable a machine. In one embodiment the status signal is produced by a comparator in response to a quantity selector and a quantity indication signal produced by the pressure-sensitive devices. In the preferred embodiment, the control system of the present invention is able to detect proper safety mat configuration, whether a threshold pressure is being applied to a pressure-sensing region in the plurality of safety mats, and whether the quantity of operatively coupled safety mats conforms to the quantity specified to be deployed.

Abstract: A pressure transducer that includes at least two sensors having substantially similar or substantially identical error characteristics, wherein each sensor is arranged to be subjected to an applied pressure and the outputs of the sensors are electrically coupled so that errors associated with one sensor are compensated by errors associated with the other sensor. The sensors may be substantially identical silicon sensors formed in close proximity on the same wafer.