Active Control for Helicopters with Slung Load by Combining ADRC and Input Shaper Technology

Abstract

Helicopters have unique characteristics enable it to flywith an underslung load in many civil and military operations. But the slung load’s pendulum-like behaviour makes it a highly hazardous and notoriously difficult task which will reduce the helicopter’s flight envelope. To eliminate the slung load’s pendulum-like behaviour, this paper discusses a control strategy for helicopters with slung load by combining Active Disturbance Rejection Control (ADRC) and Input Shaper Technology. The motion of the helicopter/load complex was modeled by the Newton-Euler equations in terms of generalized coordinates and velocities. This mathematical model was then used in conjunction with the control strategy to stabilize the helicopter/load complex. The control results by combining ADRC and Input Shaper Technology were compared with the PID control, and the improvements related to eliminate the slung load’s pendulum-like behaviour were significant.