A limit switch includes fixed contacts and a movable contact, the fixed contacts and the movable contact formed from an AuNi metal alloy of no less than 97% Au by weight. The limit switch detects position, change, movement, number of passes, or the like and outputs an on signal or an off signal depending on whether a detection occurred.

A switch has a rotary shaft that rotates in response to an external force, a cam provided on the rotary shaft and including a cam action section, wherein the cam rotates in response to the rotation of the rotary shaft, a displacement member including a cam support section that contacts the cam action section, wherein the displacement member is displaced in response to the cam support section being pressed by the cam action section rotating, and a switch module that performs an on-off action in response to the displacement of the displacement member. The cam action section is made of a metal. The cam support section is made of a resin softer than the cam action section.

A system and method for detecting end of travel in a rotational joint with greater than 360 of travel are provided. The system includes first and second limit switches coupled to the rotational joint for signaling end of travel of the rotational joint in clockwise and counterclockwise directions; a limit switch cam ring configured to actuate the first limit switch at a first rotational position in the clockwise direction and the second limit switch at a second rotational position in the counterclockwise direction, the cam ring configured to rotate in the direction of joint rotation when the rotational joint is in an ambiguity region of joint travel; first and second cam ring return mechanisms for returning the cam ring to a default position after triggering the first and second limit switches, respectively; and an actuation pin mounted to the rotational joint such that the actuation pin follows joint rotation exactly, the actuation pin configured to actuate the cam ring.