A Torque Sensor is a transducer that converts a torsional mechanical input into an electrical output signal. There are two types of Torque Sensors a reaction that measures static torque, and rotary that measures dynamic torque. Metal foil strain gauges are bonded onto a flexure or structural member that deforms when a torsional or twisting motion is applied. In most cases, four Metal foil strain gauges are used to obtain maximum sensitivity and temperature compensation. Two of the gauges are usually in tension, and two in compression, all four strain gauge are wired in a Wheatstone bridge
configuration with compensation adjustments that correct for temperature errors.