Novel Parallel Rings Design Endoscope Modelling and Co-Simulation for Minimally Invasive Surgery

Abstract

For enhancing the patient safety in Minimally Invasive Surgery (MIS), the applied pressure for actuating an endoscope should be considered carefully. This paper proposes a new pneumatic soft endoscope with Parallel Rings Design (PRD), which can accomplish the required bending at low pressure with improving the endoscope stiffness. The proposed technique is established by finite element (FE) modelling using ANSYS software with sensitivity study for the PRD dimensions. Then the sensitive parameters are enhanced using gradient based optimization technique. The system's robustness is then investigated using design of experiment (DOE) approach. The bending angle of the endoscope model is then controlled using a proportional-integral-derivative (PID) controller on MATLAB/Simulink through software-in-the-loop (SiL) approach. MATLAB receives the bending angle from FE model, and accordingly the PID coefficients are tuned then the required pressure is calculated. This pressure is returned to ANSYS, and the model's closed loop response is achieved by executing the FE model. The results show that the new PRD endoscope offers extra bending angle compared to the outer sheath endoscope at low pressure.