ClosedLoop Control of a Magnetically Actuated FiberCoupled Laser for ComputerAssisted Laser Microsurgery Patient outcomes in the medical field are improving through the use and incorporation of robotics technology and laser physics, e.g., the use of optical fibers and lasers in microsurgery. This paper describes the design and implementation of a new optical fiber laser microsurgery system, one that is the first to use closedloop feedback control. In this computerassisted laser scanning tool the laser beam is controlled by four magnetic actuators. After attaching permanent magnets to the free end of the optical fiber, it is the control of these four magnets that produces an accurate laser scanning system, one suited to microsurgery applications. The interaction between the electromagnetic fields generated by the external magnetic coils and the flux of the internal permanent magnets, produces the control torques required to produce the desired movement of the optic fiber. The tracking error of the optic fiber is compensated for by using a photodetector sensor as the feedback transducer in the control system. The magnetic torque bends the optical fiber and the feedback from the photodetector gives automated control and highspeed laser scanning of the fiber tip. The simulation and the experimental results are accurate and are corelated.

The CALM System: New Generation ComputerAssisted Laser Microsurgery This paper introduces a new generation of the motorized laser micromanipulator: The computerassisted laser microsurgery system (CALM). The system has a motorized laser micromanipulator and a graphics tablet for intuitive laser position control. The CALM system is proposed to be used in Transoral Laser Microsurgery (TLM) for accurate resections at the surgical site. This paper focuses on the technical design and control of the new motorized micromanipulator, based on a 2 degreesoffreedom spherical orienting mechanism to actuate the beamsplitter mirror. The design takes into account the constraints of the surgical setup and the mechanical space requirements in TLM. The CALM prototype has been validated through preliminary comparative user trials demonstrating that the laser positioning accuracy improves by 60% over the traditional manual system. CALM provides an intuitive mechanism and interface for improved surgical accuracy and surgical outcomes.