Project Description:
Soft pneumatic actuators, now widely explored as dexterous endoscopic tools are built from hyperelas tic materials with internal air channels. Their large strains, nonlinear elasticity, and pressure-volume
hysteresis give them many degrees of freedom, making their shape hard to predict. Modeling their deformation and bending is therefore critical, allowing us forecast the actuator’s shape inside the body,
design safe motion paths, and implement feedback control that delivers precise, gentle manipulation of tissue during minimally invasive procedures. The open-source SOFA (Simulation Open Framework
Architecture) platform addresses this need by combining real-time finite-element solvers, mechanical formulations for large rotations, and hyperelastic material models within a modular, providing both
accuracy and speed missing from many traditional dynamic models that tend to lose consistency during real-time estimation. Advances in such modeling are essential to enable predictive control algorithms
and achieve high-accuracy, real-time bending tracking.
For this master’s thesis, we will integrate the open-source SOFA simulation framework with a soft pneumatic actuator. Real-time deformation and bending measurements will be streamed into SOFA to predict internal structural deformations (similar to finite element analysis) and, together with actuator tip localization, will guide the development of robust control strategies for varied environments, ranging from simple PID controllers and optimization-based controllers such as linear-quadratic regulators (LQR).
Objectives:
- Assess the fundamental principles and simulating our existing soft pneumatic actuator in SOFA.
- Incorporate the actuator’s CAD geometry and material specifications into a SOFA model.
- Build a real time SOFA simulation pipeline that replicates the actuator’s deformation and bending under varying pressure inputs.
- Validate the SOFA model by comparing simulated tip trajectories and shapes against data from the physical actuator.
- Demonstrate position/bending real time control: use the validated SOFA simulation to inform feedback control loops for the soft actuator to in a real scenario.
Requirements for students:
- Background in control theory, including linear feedback (PID, LQR) or advanced techniques (MPC)
- Experience in programming (C++ and/or Python ) and integrating code with simulation frameworks.
- Understanding of finite-element methods (FEM) for mechanics and material modeling
- Experience in Linux is desirable