Apparatus is provided for use with a steerable catheter that includes a thumb control adapted to control a deflection of a distal tip of the catheter. The apparatus includes a robot, including an end-effector, adapted to be coupled to the thumb control, and a controller, adapted to drive the end-effector to deflect the distal tip by manipulating the thumb control. The controller has an algorithm that uses an iterative process to direct the distal tip of the catheter to a desired position, responsive to six dimensions of location and orientation information position information