Electronic Device Having a Haptic Device with an Actuation Member and a Restoration Mechanism

Abstract

A haptic device for an electronic device includes an actuation member formed from a shape-memory alloy (SMA) material that changes shape (e.g., expands or contracts) in response to an applied electrical current. In some cases, the haptic devices described herein also include a restoration mechanism that restores the actuation member to its original shape or to a similar shape. The change in the shape of the actuation member and the restoration of the shape of the actuation member may produce a haptic output at the electronic device.

What is claimed is: 
     
         1 . An electronic watch comprising:
 an enclosure;   a touch-sensitive display positioned at least partially within the enclosure;   a processing unit operably coupled to the touch-sensitive display; and   a haptic device positioned at least partially within the enclosure and configured to provide a haptic output along an external surface of the enclosure, the haptic device comprising:
 an actuation member formed from a shape-memory alloy material and configured to contract in response to a signal generated by the processing unit and produce at least a portion of the haptic output; and 
 a restoration mechanism coupled to the actuation member and configured to elongate the actuation member after a contraction of the actuation member. 
   
     
     
         2 . The electronic watch of  claim 1 , wherein:
 the actuation member is a first actuation member formed from a first shape-memory alloy material;   the signal is a first signal;   the restoration mechanism comprises a second actuation member formed from a second shape-memory alloy material; and   the second actuation member is configured to contract in response to a second signal generated by the processing unit.   
     
     
         3 . The electronic watch of  claim 1 , wherein:
 the enclosure comprises a cover defining at least a part of a front external surface of the enclosure and a contact member defining at least a part of a rear external surface of the enclosure;   a graphical output of the touch-sensitive display is visible along the front external surface;   the rear external surface is configured to contact a body part of a user; and   the haptic device is configured to produce the haptic output along the rear external surface by moving the contact member relative to the cover.   
     
     
         4 . The electronic watch of  claim 3 , wherein the haptic output is coordinated with a change in the graphical output. 
     
     
         5 . The electronic watch of  claim 3 , wherein the haptic device is configured to rotate the contact member. 
     
     
         6 . The electronic watch of  claim 3 , wherein the haptic device is configured to translate the contact member along either:
 a path that is parallel to the front external surface; or   a path that is perpendicular to the front external surface.   
     
     
         7 . The electronic watch of  claim 1 , wherein:
 the electronic watch comprises a crown that is configured to receive a rotational input; and   the haptic output is provided in response to the rotational input.   
     
     
         8 . The electronic watch of  claim 1 , wherein:
 the actuation member is a first actuation member;   the signal is a first signal;   the shape-memory alloy material is a first shape-memory alloy material;   the first actuation member is configured to produce a first portion of the haptic output; and   the restoration mechanism includes a second actuation member that is configured to produce a second portion of the haptic output in response to a second signal.   
     
     
         9 . An electronic device comprising:
 an enclosure;   a display positioned at least partially within the enclosure;   an actuation member comprising a shape-memory alloy and positioned within the enclosure, the actuation member configured to change from a first shape to a second shape in response to an electrical signal;   a restoration mechanism coupled to the actuation member and configured to restore the actuation member from the second shape to the first shape; and   a processing unit operably coupled to the actuation member and configured to cause the electrical signal to be applied to the actuation member, wherein:   changing the actuation member from the first shape to the second shape produces a first portion of a haptic output along an external surface of the enclosure; and   restoring the actuation member from the second shape to the first shape produces a second portion of the haptic output along the external surface of the enclosure.   
     
     
         10 . The electronic device of  claim 9 , wherein:
 the enclosure comprises:
 a cover positioned over the display; 
 a housing member defining an opening; and 
 a rear cover positioned in the opening and coupled to the actuation member; and 
   the actuation member causes the rear cover to move relative to at least one of the cover or the housing member to produce the first portion of the haptic output.   
     
     
         11 . The electronic device of  claim 10 , wherein:
 changing the actuation member from the first shape to the second shape causes the rear cover to move in a first direction; and   restoring the actuation member from the second shape to the first shape causes the rear cover to move in a second direction that is opposite to the first direction.   
     
     
         12 . The electronic device of  claim 10 , wherein the actuation member causes the rear cover to rotate relative to at least one of the cover or the housing member. 
     
     
         13 . The electronic device of  claim 10 , wherein:
 the rear cover comprises an electrode for determining an electrocardiogram; and   the haptic output is provided in response to determining the electrocardiogram.   
     
     
         14 . The electronic device of  claim 9 , wherein:
 the actuation member is a first actuation member;   the shape-memory alloy is a first shape-memory alloy; and   the restoration mechanism comprises a second actuation member formed from a second shape-memory alloy.   
     
     
         15 . The electronic device of  claim 9 , wherein the restoration mechanism comprises a spring. 
     
     
         16 . A method for producing a haptic output using an actuation member comprising a shape-memory alloy, the method comprising:
 detecting an input at an electronic device using a processing unit of the electronic device;   in response to the input, producing an output signal;   in response to the output signal, applying an electrical current to an actuation member thereby causing the actuation member to contract and produce a first portion of the haptic output; and   elongating the actuation member using a restoration mechanism thereby producing a second portion of the haptic output.   
     
     
         17 . The method of  claim 16 , wherein elongating the actuation member of the electronic device comprises applying a tensile force to the actuation member using the restoration mechanism. 
     
     
         18 . The method of  claim 16 , wherein:
 the electrical current is a first electrical current; and   the method further comprises, after the actuation member is elongated, contracting the actuation member by applying a second electrical current to the actuation member to produce a third portion of the haptic output.   
     
     
         19 . The method of  claim 16 , wherein:
 the method further comprises displaying a graphical output using a touch-sensitive display; and   detecting the input comprises detecting a touch input along the touch-sensitive display.   
     
     
         20 . The method of  claim 16 , wherein:
 detecting the input comprises determining an electrocardiogram using one or more voltages detected using the electronic device; and   the haptic output is provided in response to determining the electrocardiogram.