Fuzzy control method to minimize the needle deflection during needle insertion therapy

A fuzzy control algorithm is adopted to help the needle hit the target more accurately. The experimental setup for the needle insertion is built up to validate the algorithm. How the forces dur- ing the insertion make the needle deflect away from the planned path is given, and the normal meth- od correcting the deflection is obtained accordingly. Because the normal method cannot perform well for correction, a fuzzy controller is established. The input module, output module, fuzzification module, defuzzification module and inference engine for the controller are given respectively accord- ing to the fuzzy theory. Our experimental results show that the fuzzy controlling system presenting in the paper can better eliminate the deflection.