A linear displacement device includes at least one artificial muscle actuator, an arm attached to the at least one artificial muscle, a body that is restricted to move along a line, and a stationary channel that restricts the motion of the body to linear motion. The at least one artificial muscle actuator causes the body to move along the line. The body is further restricted to move along a surface of the arm and the at least one artificial muscle actuator is a rotational muscle actuator. Additionally, the arm rotates in concert with the at least one artificial muscle actuator.