Crown sensing system for an electronic watch

1 . An electronic watch comprising:

a housing defining a side wall;

a display positioned at least partially in the housing;

an input system comprising:

a mounting bracket coupled to the housing;

a crown coupled to the mounting bracket and configured to rotate and translate with respect to the housing, the crown comprising:

a knob positioned external to the housing; and

a shaft assembly coupled to the knob and extending into the housing;

a plate defining a first end and a second end and coupled to the mounting bracket at the first end and the second end, wherein the shaft assembly contacts the plate between the first and second ends and the plate is configured to be bent by the shaft assembly in response to a translation of the crown; and

a strain sensing element coupled to the plate; and

a processing system operably coupled to the strain sensing element and configured to detect the translation of the crown based at least in part on a signal from the strain sensing element.

2 . The electronic watch of claim 1 , wherein:

the shaft assembly contacts a first side of the plate; and

the strain sensing element is coupled to a second side of the plate, opposite the first side of the plate.

3 . The electronic watch of claim 1 , wherein:

the crown is translatable between a default position and a pressed position; and

the plate biases the crown in the default position.

4 . The electronic watch of claim 3 , wherein:

the mounting bracket defines a translation path of the crown between the default position and the pressed position; and

the plate remains within an elastic deformation condition throughout the translation path of the crown.

5 . The electronic watch of claim 1 , wherein:

the plate comprises a metal beam;

a first end of the metal beam is coupled to the mounting bracket; and

the strain sensing element comprises a strain gauge coupled to the metal beam.

6 . The electronic watch of claim 1 , wherein:

the electronic watch further comprises a rotation sensing element coupled to the mounting bracket; and

the processing system is further configured to determine rotation of the crown based at least in part on information from the rotation sensing element.

7 . The electronic watch of claim 1 , wherein the plate is configured to be moved by the shaft assembly in response to a pivoting motion of the crown.

8 . The electronic watch of claim 7 , wherein:

the plate defines an opening; and

the shaft assembly defines a coupling feature that extends into the opening, wherein the coupling feature is configured to move the plate in response to the pivoting motion of the crown.

9 . The electronic watch of claim 8 , wherein:

the signal from the strain sensing element is a first signal; and

the processing system is further configured to detect the pivoting motion of the crown based at least in part on a second signal from the strain sensing element.

10 . A wearable electronic device comprising:

a housing having a side wall;

a display coupled to the housing;

a haptic system coupled to the housing; and

an input system comprising:

a bracket assembly coupled to the housing;

a crown positioned along the side wall and comprising a shaft assembly extending through the side wall, the crown coupled to the bracket assembly and configured to rotate and translate with respect to the bracket assembly;

a plate coupled to the bracket assembly and configured to be deformed by the shaft assembly in response to translation of the crown, wherein the plate comprises a first end coupled to the bracket assembly and a second end coupled to the bracket assembly and the shaft assembly contacts the plate substantially midway between the first end and the second end; and

a strain sensing element coupled to the plate and configured to output a signal indicating a deformation of the plate.

11 . The wearable electronic device of claim 10 , further comprising a processing system operably coupled to the input system, wherein:

in response to the signal satisfying a threshold, the processing system is configured to register a crown press; and

in response to registering the crown press, the processing system is configured to cause the haptic system to generate a haptic output.

12 . The wearable electronic device of claim 11 , wherein, in response to registering the crown press, the processing system is configured to change a graphical output of the display.

13 . The wearable electronic device of claim 11 , further comprising a rotation sensing system configured to detect a rotation of the crown, wherein:

the haptic output is a first haptic output; and

in response to detecting the rotation of the crown with the rotation sensing system, the processing system is configured to cause the haptic system to generate a second haptic output, different from the first haptic output.

14 . The wearable electronic device of claim 10 , wherein the strain sensing element is coupled to the plate substantially midway between the first and second ends.

15 . The wearable electronic device of claim 10 , wherein the plate comprises a metal beam.

16 . An electronic watch comprising:

a housing;

a display;

an input system coupled to the housing and comprising:

a bracket assembly coupled to the housing;

a crown coupled to the bracket assembly and comprising a shaft assembly extending through the housing, the crown configured to rotate and translate with respect to the housing;

a plate having a first end coupled to the bracket assembly and a second end coupled to the bracket assembly, the plate configured to be deformed in response to the shaft assembly pressing on the plate between the first end of the plate and the second end of the plate as a result of a translation of the crown; and

a strain sensing element coupled to the plate and configured to indicate a deformation of the plate; and

a processing system operably coupled to the input system and configured to change a graphical output of the display in response to the deformation of the plate satisfying a threshold.

17 . The electronic watch of claim 16 , further comprising a haptic system coupled to the housing and operably coupled to the processing system, wherein the processing system is configured to cause the haptic system to generate a haptic output in response to the deformation of the plate satisfying the threshold.

18 . The electronic watch of claim 17 , wherein:

the bracket assembly defines a translation path substantially along an axis of the shaft assembly; and

the strain sensing element is configured to detect an amount of deformation of the plate from the translation of the crown.

19 . The electronic watch of claim 16 , further comprising a rotation sensing system configured to detect a rotation of the crown, wherein:

the processing system causes a first graphical output at the display in response to detecting translation of the crown; and

the processing system causes a second graphical output at the display in response to detecting the rotation of the crown.

20 . The electronic watch of claim 19 , further comprising:

a biometric sensing system; and

a conductive member electrically coupling the crown to the biometric sensing system; and wherein:

the crown is electrically isolated from the bracket assembly; and

the crown is configured to transmit an electrical signal from a user and to the biometric sensing system.