Input-output tracking control of a 2-DOF laboratory helicopter with improved algebraic differential estimation

摘要

This paper presents a study on input-output feedback linearization control (OFLC) of a laboratory twin rotor helicopter system based on an improved algebraic differential estimation approach. In the previous algebraic differential estimation studies, the reset time T-r is always selected cautiously in a narrow range because the estimation accuracy is very sensitive to T-r. Too small or too large reset time T-r will lead to an inaccurate estimation of signal derivatives. In this paper, we first propose a new resetting and overlapping strategy for improving the robustness of the estimation algorithm. Then it is used to estimate the velocities of pitch and yaw motions. The OFLC is designed and verified by letting the output signals track different periodic reference signals. Both simulation and experimental results show better control performance as compared with the LQR design. (C) 2018 Elsevier Ltd. All rights reserved.