Patent attributes
A sensing apparatus comprising: a displacement sensor comprising capacitance measurement circuitry configured to provide a displacement sensor output signal indicative of a separation between a frame element and a displacement element movably mounted with respect to the frame element; a touch sensor comprising measurement circuitry configured to provide a touch sensor output signal indicative of when an object is determined to be touching the displacement element; and a processing element configured to output a displacement detection signal to indicate there is determined to be a displacement of the displacement element relative to the frame element in response to determining the touch sensor output signal indicates an object is touching the displacement element and a difference between the displacement sensor output signal and a baseline displacement sensor output signal exceeds a threshold value, wherein the baseline displacement sensor output signal is determined from the displacement sensor output signal in a time period determined from when the touch sensor output signal initially indicates the object is touching the displacement element.