Direct synthesis approach to design PDμ${\text{PD}}^\mu$ based smith predictor for integrating plants: Studied on a quadrotor UAV

Abstract

This article presents a simple yet novel method of designing a fractional‐order proportional derivative (namely, ) controller for all types of integrating plants. Considering the importance of the direct synthesis approach, the method obtains robust closed‐loop performance. The setpoint parameter is obtained using the multi‐optimization Pareto solution, considering the optimal values in control efforts and performance index together. The numerical investigations have shown improved servo and regulatory responses compared to recently published strategies with fractional orders. It is also known that classical PIDs cannot accurately follow a ramp setpoint. A real‐world situation also demands that the reference inputs become an acceleration ramp type. The proposed technique can handle rising ramp setpoints with plant uncertainty and measurement noise. Hardware verification is also performed on a quadrotor minidrone to check for real‐time issues.