Lyapunov Control Law for Automatic Approach for Unmanned Helicopter Landing

Jangho LEE, Seong Pil KIM, Dongho SHIN, Hyoung Sik CHOI, Kie Jeong SEONG, Youdan KIM
2011 Transactions of the Japan Society for Aeronautical and Space Sciences  
Describing the flight behavior of a helicopter is a difficult challenge in mathematical modeling. A rotorcraft can be considered as a complex arrangement of interacting subsystems, and the problem is dominated by rotor. The rotor blades bend and twist under the influence of unsteady and nonlinear aerodynamic loads, which are themselves a function of blade motion. This problem makes it more difficult to estimate the behavior of a helicopter. Furthermore, it is difficult to design a flight
more » ... ler for unmanned helicopter systems. In this paper, to obtain a nonlinear dynamic model of a helicopter, parameter identification is performed using flight test data. A globally stable tracking control law for agile and precise landing of an unmanned helicopter is proposed. A near-minimum time control scheme is adopted to design the reference trajectory, and it is shown that the control law is guaranteed to be stable globally in the sense of Lyapunov. A flight test verified the performance of the proposed method. Performance can be improved by choosing the control parameters via optimization. The proposed method can be extended to a multiple output trajectory tracking problem for a precise fixed-wing UAV landing.
doi:10.2322/tjsass.53.283 fatcat:dpnplnyekzaabimboy7cvjsrau