Fuzzy-enhanced integral augmented sliding mode control for a dual-cavity soft pneumatic actuator: design, modelling, and control

Advancements in soft robotic technology have led to the development of various human-like soft designs with enhanced capabilities to replicate targeted functions. A major challenge in this field is developing accurate models to represent the soft materials in alignment with the chosen actuation method. Additionally, creating precise control schemes to manage their inherent nonlinearity while delivering the required control action is critical. In this study, we present a mathematical model of the pressure dynamics for a dual-cavity pleated structure soft pneumatic actuator (DCPS-SPA), actuated via a three-outlet–two-inlet solenoid valve within a pneumatic circuit using an energy-based approach. We propose a fuzzy-based integral augmented sliding mode control combined with an improved enhanced exponential reaching law (FISMC+IEERL) for pressure control in the SPA. The performance of the proposed control strategy is compared with other successive sliding mode control (SMC) schemes. Both experimental and simulation results demonstrate the capability of the designed control scheme to provide precise pressure control in the SPA with minimal error and optimized control action.