Dynamic force control for a miniaturised medical robot system

The goal of this project was the realisation of an autoclavable mobile miniature robot that can be integrated easily into a standard OR. The new miniature robot consists of an positioning unit with two or four active and two passive axes (position at z-axis and rotation around z-axis). The unit has to be positioned versus the patient under navigation control and is fixed rigidly by a mechanical arm. The system integrates the robots work space and the planning model within an optical and electromechanical controlled execution mode. The miniature robot reaches an absolute accuracy of about 0.5 mm reproducibility equal to competitive navigation and robot assisted systems. Forces of up to 20 N can be generated by the positioning unit while the system stays fixed. The increment interpretation of constant torque impulses permits the quantitative determination of contact forces up to 20 N with a deviation of max. 20 %. The system is fully compatible to the standard OR and its accuracy as well as its stability is high. Due to its transparent system structure and modular concept, the miniature robot can be used within a wide range of medical application.