Devices, systems and methods for controlling cable drive mechanisms

A manipulator system for supporting and remotely actuating instruments, comprising:

• a manipulator comprising a first link, an instrument carriage, and a joint coupling the instrument carriage relative to the first link, wherein:
• the instrument carriage is configured to support an instrument;
• the joint comprises:
• a capstan mechanism;
• one or more cables coupled to the instrument carriage;
• and
• one or more pulleys routing the cables between the instrument carriage and the capstan mechanism, wherein the capstan mechanism comprises:
• a capstan comprising an outer surface;
• a groove in the outer surface of the capstan, the groove configured to receive and guide a cable to spool onto the capstan as the capstan rotates;
• one or more take-up pulleys to route the one or more cable onto and off from the capstan;
• and
• a guide element engaged with the groove, the guide element causing relative translation between the capstan and the one or more take-up pulleys in response to rotation of the capstan.