Abstract: A robot of the type having a housing and a manipulator mounted to the housing and movable along a plurality of predetermined axes of movement. A drive mechanism is associated with the each axis of movement for moving, upon actuation, the manipulator along its respective axis of movement. The actuation of the drive mechanisms is controlled by a program drum which is rotatably mounted to the housing. A plurality of cam segments are adjustably secured to the drum at both axially and circumferentially spaced positions thus forming a plurality of axially spaced, segmented cam rings. A plurality of cam followers are secured to the housing so that one cam follower registers with each cam ring. Each cam follower is connected with an actuator so that, when the cam follower engages a cam segment on the drum, the actuator activates the drive mechanism corresponding to the particular cam ring. Conversely, the actuator deactivates its associated drive mechanism when the cam follower disengages from the cam segment.