Input systems with adjustable input thresholds
An electronic device may include an input system that includes an input member accessible on the exterior of the electronic device and configured to receive a user-applied input force, a beam structure configured to deflect as a result of the input force, a strain sensing system, and a switch that may be actuated by movement of the input member. When the switch is actuated, the electronic device may use a signal provided by the strain sensing system to determine an actuation force of the switch and may further use the determined actuation force to determine a threshold associated with a partial press of the button. The electronic device may include a temperature sensor that provides a temperature signal. The electronic device may use the temperature signal to determine an offset to apply to the signal provided by the strain sensing system.
1 . A method, comprising:
monitoring an operating state of a button including an input member, a beam structure configured to be deflected as a result of a force input applied to the input member, a strain sensing system configured to generate an output signal based on deflection of the beam structure, and a switch configured to be actuated by movement of the input member, wherein:
the output signal satisfying a threshold indicates a first operating state of the button; and
actuation of the switch indicates a second operating state of the button;
detecting an instance of actuation of the switch;
determining, using the output signal, an actuation force corresponding to the instance of actuation of the switch;
determining an adjustment to the threshold using the determined actuation force.
2 . The method of claim 1 , comprising:
applying the determined adjustment to the threshold to change the threshold from a first value to a second value.
3 . The method of claim 1 , comprising determining user contact with a first contact location of the input member during actuation of the switch, wherein:
the threshold is a first threshold associated with the first contact location; and
determining the adjustment to the threshold comprises determining a first adjustment to the first threshold.
4 . The method of claim 3 , comprising determining, based on the determined actuation force, a second adjustment to a second threshold associated with a second contact location of the input member.
5 . The method of claim 1 , wherein determining the actuation force of the switch comprises:
generating a set of output samples from the output signal;
removing one or more output samples from the set of output samples, to generate a subset of output samples; and
determining the actuation force based on the subset of output samples.
6 . The method of claim 5 , wherein removing the one or more output samples from the set of output samples comprises:
performing a linear fit using the set of output samples; and
removing the one or more output samples based on the linear fit.
7 . The method of claim 1 , wherein the switch is a dome switch and actuation of the switch corresponds to dome switch collapse.
8 . The method of claim 1 , wherein the first operating state of the button corresponds to a half button-press.
9 . The method of claim 1 , wherein when the button is in the first operating state a first operation of an electronic device is performed and when the button is in the second operating state a second operation of the electronic device, different from the first operation, is performed.
10 . An input system of an electronic device, comprising:
an input member;
a beam structure configured to be deflected as a result of an input force applied to the input member;
a strain sensing system configured to generate an output signal based on deflection of the beam structure;
a switch configured to be actuated by movement of the input member;
processing circuitry configured to:
receive the output signal;
determine an operating state of the input system, wherein:
the output signal satisfying a threshold indicates a first operating state of the input system; and
actuation of the switch indicates a second operating state of the input system;
detect an instance of actuation of the switch;
determine, using the output signal, an actuation force corresponding to the instance of the actuation of the switch; and
determine an adjustment to the threshold using the determined actuation force.
11 . The input system of claim 10 , comprising a touch sensor associated with the input member and configured to generate a touch signal, and wherein the processing circuitry is configured to:
receive the touch signal; and
determine, based on the received touch signal, a user contact with the input member at a first contact location of a set of contact locations; wherein:
determining the actuation force comprises determining a first actuation force corresponding to the first contact location.
12 . The input system of claim 11 , wherein:
determining the actuation force comprises determining a second actuation force corresponding to a second contact location of the set of contact locations.
13 . The input system of claim 10 , wherein determining the actuation force of the switch comprises:
generating a set of output samples from the output signal;
removing one or more output samples from the set of output samples, to generate a subset of output samples; and
determining the actuation force based on the subset of output samples.
14 . The input system of claim 13 , wherein removing the one or more output samples from the set of output samples comprises:
performing a linear fit using the set of output samples; and
removing the one or more output samples based on the linear fit.
15 . The input system of claim 10 , wherein the first operating state of the input system corresponds to a half button-press.