Nonlinear Robust Control on Yaw Motion of a Variable-Speed Unmanned Aerial Helicopter under Multi-Source Disturbances

Abstract

This paper studies the multi-source disturbances attenuation problem on the yaw motion of unmanned aerial helicopter with a variable-speed rotor. The yaw motion subsystem dominated by an electrically-driven tail rotor is firstly introduced, and its trajectory accuracy requires particularly close attention. To this end, we establish a fourth-order yaw error dynamic equation; subsequently, a nonlinear robust control scheme based on optimal H∞ principle is developed, consisting of laws of virtual functions, parameter estimation and a compensation signal. The novelty of this scheme lies in unifying the techniques to deal with the uncertain parameters, noise perturbations, actuator output fault and external airflow turbulence into a simple framework. Stability analysis guarantees that the yaw closed-loop system has the predefined performance of disturbance suppression in the sense of a finite L2-gain. Comparison results with the extended state observer based backstepping controller verify the effectiveness and superior performance of proposed scheme in an aircraft prototype.

Attitude Autopilot Design Based on Fuzzy Linear Active Disturbance Rejection Control

“…In recent years, many advanced control theories have been implemented in control system design, including robust control [7,8], adaptive control [9,10], linear quadratic regulation [11,12], sliding mode control [13,14] and intelligent control algorithm [15][16][17], etc. In [18], a robust adaptive neural network certainty equivalent controller for a quadrotor unmanned aerial vehicle was proposed.…”