US 11,755,166 B2
Displacement sensing
Peter Timothy Sleeman, Waterlooville (GB); and Robert Money, Fareham (GB)
Assigned to TouchNetix Limited, Fareham (GB)
Appl. No. 16/640,124
Filed by TouchNetix Limited, Fareham (GB)
PCT Filed Aug. 29, 2018, PCT No. PCT/GB2018/052434
§ 371(c)(1), (2) Date Feb. 19, 2020,
PCT Pub. No. WO2019/048827, PCT Pub. Date Mar. 14, 2019.
Claims priority of application No. 1714301 (GB), filed on Sep. 6, 2017.
Prior Publication US 2021/0191574 A1, Jun. 24, 2021
Int. Cl. G06F 3/044 (2006.01); G01L 1/14 (2006.01); H03K 17/975 (2006.01)
CPC G06F 3/0447 (2019.05) [G01L 1/142 (2013.01); G06F 3/0445 (2019.05); H03K 17/975 (2013.01); G06F 2203/04105 (2013.01); H03K 2217/9651 (2013.01)] 13 Claims
OG exemplary drawing
 
1. 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 processor configured to output a 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 when the touch sensor outputs a touch sensor output signal indicative of when an object is determined to be touching the displacement element, the processor is configured to determine the baseline displacement sensor output signal for a duration of the detected touch of the object from the displacement sensor output signal during a time period defined by when the touch sensor output signal initially indicates the object is touching the displacement element, such that the baseline displacement sensor output signal maintains a fixed value for the duration of the detected touch of the object, wherein the baseline displacement sensor output signal is set to the displacement sensor output signal when no touch of an object is sensed by the touch sensor.