Model Predictive Control For 3 D Steerable Needles A Hierarchical Approach To Reduce Tissue Trauma

This paper presents a three-dimensional (3D) control framework for bevel-tip steerable needles that combines model predictive control (MPC) with hierarchical supervisory logic. The MPC layer uses a reduced-order two-mode switching model to generate the desired control actions, while the supervisory logic adaptively prioritizes in-plane and out-ofplane corrections based on real-time error magnitudes. This hierarchical approach smoothly modulates the axial rotation commands to minimize abrupt needle flips, thereby reducing the so-called “drilling effect”, a key source of tissue trauma. The simulation results show that the proposed approach reduces tissue trauma by more than 50% compared to conventional pulse-width-modulated sliding mode controllers while achieving mean absolute error and targeting errors in the submillimeter range.