A system is used for robotically controlling movement of a human-controllable catheter, wherein the catheter has a distal end and at least one position sensor for generating or receiving signals used for determining six dimensions of location and orientation information of the distal end of the catheter. The system uses a robotic control mechanism for holding and manipulating a human-controllable catheter and a computer operatively communicating with the robotic control mechanism for driving the robotic control mechanism to (i) translationally move a distal end of a human-controllable catheter in a vicinity of a target, (ii) deflect a distal end of a human-controllable catheter, and (iii) rotate a human-controllable catheter in a vicinity of a target. The computer determines roll of a human-controllable catheter using six dimensions of location and orientation information based on signals generated or received from at least one position sensor on a human-controllable catheter.
