Sliding Mode Control of Catheter Drive System and Performance Improvement via Fuzzy Logic

Catheters are used in medical applications such as bronchoscopy, colonoscopy, angiography. Due to the catheters are in direct contact with the tissue in these procedures, their movements must be controlled. In this study, three different sliding-mode controllers that can be used to control the movement of the catheter have been proposed. These are the classical sliding mode controller, quasi sliding mode controller, and asymptotic sliding mode controller structures. Performance comparison of the controllers was made by assessing the closed-loop system response. The results indicated that the performance of the quasi sliding mode controller was better than the other controllers. It has been proposed to use a fuzzy logic-based highest controller to improve the performance of the quasi sliding mode controller. The proposed controller structure updates the controller parameters depending on the predicted disturbance magnitude and position error. The results show that the real-time performance of the quasi sliding mode controller is improved by the change of the proposed control structure.