User Interface System

A user interface system for receiving a user input that includes sheet that defines a surface and at least partially defines a fluid vessel arranged underneath the surface, a volume of fluid within the fluid vessel, a displacement device that influences the volume of the fluid within the fluid vessel to expand and retract at least a portion of the fluid vessel, thereby deforming a particular region of the surface, and an electrical sensor coupled to the sheet that receives an input provided by a user that inwardly deforms the surface of the sheet and that includes a first conductor and a second conductor that are electrically coupled to each other with an electrical property that changes as the distance between the first and second conductors changes.