Abstract: A general-purpose force sensor, which can be used with an orthotic device, is provided utilizing both resistive and capacitive techniques for improved accuracy and reliability compared to either type of sensor alone. The system can detect internal fault conditions and continues to operate correctly despite the failure of one of the sensors. The sensor can be self-calibrating to give accurate readings despite changes in the physical properties of the sensing elements over time.

Abstract: A general-purpose force sensor, which can be used with an orthotic device, is provided utilizing both resistive and capacitive techniques for improved accuracy and reliability compared to either type of sensor alone. The system can detect internal fault conditions and continues to operate correctly despite the failure of one of the sensors. The sensor can be self-calibrating to give accurate readings despite changes in the physical properties of the sensing elements over time.

Abstract: A single chip operational amplifier wherein the gain is programmable by means of a digitally controlled feedback loop wherein the parameters of the feedback circuit are digitally programmable under control of a microprocessor, microcontroller, control logic and the like. There is provided an operational amplifier with a feedback loop from output terminal to input terminal. The feedback loop contains components which are switched into the feedback loop circuit under control of digital signal provided by an external device, such as, for example, a microprocessor, microcontroller, control logic and the like. The digital signals from the external device cause the appropriate resistors and/or capacitors and/or other components, as may be required, to be switched into the feedback loop of the operational amplifier to provide the desired gain. These digital signals can be derived from a monitoring source which is designed to provide automatic gain control (AGC) or the like.