Patent ID: 8151661

Claim:
A compact capstan comprising: a cable loop having a first end and a second end; a drum having a cylindrical surface, a first end, and an opposite second end, the cylindrical surface of the drum having a spiral groove to receive the first end of the cable loop attached to a first cable attachment point at a first end of the spiral groove and the second end of the cable loop attached to a second cable attachment point at a second end of the spiral groove with a loop portion of the cable loop that is fed out at one end and drawn in at an opposite end between the first and second ends of the spiral groove such that the loop portion maintains a constant length; a threaded hub coupled to the first end of the drum, the threaded hub to engage a threaded support, the threaded hub and the drum to move together laterally along their length relative to the threaded support in response to being rotated; and a splined shaft rotatably supported in a fixed relationship to the threaded support, the splined shaft engaging a ball spline nut coupled to the drum and the hub to transmit a torsional force to rotate the drum and the hub, the ball spline nut, the drum and the hub being free to move along the length of the splined shaft.