Abstract:
Powered parafoil system is strongly nonlinear and contains complicated cross-coupling characteristic, which makes the system hard to control. Under the variable wind disturbance, this coupling influence will aggravate the control performance, probably resulting in large deviations or instability in the control process. An active disturbance rejection control (ADRC) strategy based on the coupling compensation was proposed. The dynamic cross-coupling relation of the longitudinal thrust on the lateral yaw control was designed as the known disturbance of extended state observer (ESO) to be compensated in the improved control law, so that the tracking ability of the controller could be enhanced. Moreover, under the cross-coupling compensation, a complex nonlinear powered parafoil system was constructed as integrators which could be easily controlled, such that the tracking precision and disturbance rejection capacity of the lateral controller were improved. Eventually, mathematical simulations demonstrate that the proposed control approach has better tracking performance and robustness compared with the conventional ADRC and PID.