Multiphysics Model and Hysteresis Compensation for Control of Electroactive Actuators

Abstract

Electroactive polymer actuators based on PVDF-TrFE-CTFE terpolymers are gaining prominence in applications requiring compliant, high-precision actuation, notably in soft robotics for minimally invasive surgical tools. However, the relaxor ferroelectric properties of these materials introduce significant nonlinear hysteresis, which impairs control accuracy. This paper presents a model-based control architecture that overcomes these challenges by integrating an analytically inverted generalized Prandtl-Ishlinskii hysteresis model with model predictive control (MPC). The proposed framework effectively linearizes the hysteresis behavior while optimizing control inputs under actuator constraints, ensuring rapid response and zero steady-state error in quasi-static regimes. The developed model has been compared against experimental measurements of actuator deflection and electric displacement, demonstrating strong correlation between predicted and observed behavior. Numerical simulations demonstrate that the MPC strategy achieves short settling times and improved trajectory tracking compared to conventional proportional-integral-derivative control. These results underscore the potential of the integrated approach for precision-critical urological applications.