Designing and Testing a Closed-Loop Magnetically Actuated Laser Scanning System for Tissue Ablation

Biomedical robotic systems continue to hold unlimited potential for surgical procedures. Robotized laser endoscopic tools provide surgeons with increased accuracy in the laser ablation of tissue and tumors. The research here catalogs the design and implementation of a new laser endoscopic tool for tissue ablation. A novel feature of this new device is the inclusion of a feedback loop that measures the position of the laser beam via a photodetector sensor. The scale of this new device was governed by the dimensions of the photodetector sensor. The tip of the laser's fiber optic cable is controlled by the torque interaction between permanent magnet rings surrounding the fiber-optic and the custom-designed solenoid coils. Prior to building the physical test-bed, the system was modeled and simulated using COMSOL software. In preclinical trials, the physical experimental results showed that the designed prototype laser scanner system accurately tracks different ablation patterns and gives a consistent output position for the laser beam; however, the heat diffusion into the tissue around the desired line of the geometric shape would give wider ablation margins than was desirable.