A device includes a first mechanism having a surface and a helical slot in the surface, a second mechanism having a periphery and an axial slot in the periphery, and an insert comprising a pin. The second mechanism is located within the first mechanism. The insert is located within the second mechanism. The pin extends from the insert through the axial slot of the second mechanism and into the helical slot of the first mechanism. The insert is configured to couple to an instrument. In some embodiments, the insert is configured to move the instrument in a degree of freedom in response to the second mechanism being held stationary and the first mechanism being rotated. In some embodiments, the degree of freedom is an insertion and retraction degree of freedom.
