Abstract: Disclosed is an input device comprising (a) a base support, having a periphery and a plurality of apertures formed therein to define a circumscribed or circumscribing input pad configured to displace under the applied force; (b) a plurality of isolated beam segments, defined by the plurality of apertures, and operable to receive resultant forces distributed to the isolated beam segments by the displacement of the input pad; (c) at least two sensors, disposed along each isolated beam segment, and configured to measure the forces transmitted from the input pad to the periphery and to output a signal corresponding to the applied force. One or more processing means operable with the plurality of sensors may be utilized to receive the signal and to determine at least one of a location and/or magnitude of the applied force acting on the input pad.

Abstract: A system and method for detecting a shock to a force-based touch panel is disclosed. The system comprises at least one force sensor operable with the force-based touch panel to measure a force applied to the touch panel to provide at least one force sensor signal. An accelerometer is used to sense vibrational acceleration of the force-based touch panel to form an acceleration signal. A shock detector is used to inhibit detection of a touch event on the touch panel for a predetermined period when an amplitude of the correlated shock signal is greater than a selected threshold.

Abstract: Disclosed is a method for determining a force sensor signal baseline in a force-based input device. The method includes accepting a signal associated with touch activity and determining a signal range, wherein the signal range decays with time and is reset when the signal exceeds the current range. A touch event is declared when the signal range exceeds a predetermined activity threshold. A previously determined baseline is held when a touch event is declared, and updated when a touch event is not declared.

Abstract: A system and method for reducing vibrational effects on a force-based touch panel is disclosed. The system comprises at least one force sensor operable with the force-based touch panel to measure a force applied to the touch panel to provide at least one force sensor signal. An accelerometer operable with the force-based touch panel is used to sense a vibrational acceleration of the force-based touch panel to form an acceleration signal. The vibrational acceleration adds a vibration induced signal to the at least one force sensor signal. An adaptive vibration filter is used to adaptively filter the vibration induced signal from the at least one force sensor signal by adjusting filter characteristics of the adaptive vibration filter to remove substantially all of the vibration induced signal from the at least one force sensor signal.

Abstract: Disclosed is method and device for compensating a force sensor signal for baseline error in a force-based touch screen. In one embodiment, baseline compensation includes determining a decaying maximum value and a decaying minimum value of the force sensor signal, and subtracting these values to obtain a range value. When the range value is less than a predetermined activity threshold, updating of the baseline is disabled. The decaying maximum value and decaying minimum value are reset to the current value of the force sensor signal when exceeded by the current value of the force sensor signal.