A novel displacement accurate tracking algorithm to improve the effectiveness of SASC pneumatic system in practical applications

Nonlinear dynamics and parametric uncertainties impede precision control of single-acting spring-cylinder (SASC) pneumatic systems in industrial automation. This work establishes a dynamics model characterizing the SASC as a strict-feedback nonlinear system with unmeasurable states. To overcome these limitations, we develop a novel displacement tracking algorithm integrating a fuzzy-logic state observer for uncertainty compensation and an adaptive backstepping controller for nonlinearity mitigation. Experimental validation on a dedicated test bench demonstrates 77.1% lower steady-state error and 90.1% suppressed overshoot compared to benchmark methods, while sustaining sub-0.023 mm positioning accuracy under flow saturation and hysteresis effects. Comparative analysis confirms superior transient stability over PID and NN algorithms, providing a practically deployable framework for enhancing industrial pneumatic control precision.