Path-tracking control of bevel-tip needles using Model Predictive Control

The bevel-tip flexible needle is an improvement of the clinical puncture needle and has the potential to reduce surgery traumas and improve puncture accuracy. Due to the nonholonomic kinematics model, it is difficult to drive flexible needles to track a pre-plan path. In this paper, we propose an effective path tracking control method based on Model Predictive Control (MPC). The kinematics model of flexible needles is described firstly, according to which the control method is designed. Then, the path tracking control method is presented in detail. The finite prediction horizon of MPC is extended to infinite in order to obtain a global optimal solution. Due to the nonlinear model, the objective function of receding horizon optimization is also nonlinear, and Particle Swarm Optimization (PSO) is employed to search optimal predictive control series. At last, simulations are conducted and results illustrate that the proposed controller performs well to precisely drive the flexible needle to track a desired path.