Abstract：Aiming at the saturation nonlinearity in the yaw channel of a small-scale unmanned helicopter, a switch model based identification method for the unmanned helicopter yaw channel is proposed. Firstly, the characteristics of the yaw channel are analyzed and a switch model including a saturation unit for the controller is established. Experimental data for the model identification are collected by utilizing some sweep frequency control signals. Based on the data, the parameters of the switch model are identified through the genetic algorithm method. The residual error signal is calculated, analyzed and utilized to modify the model obtained, and thus the accuracy of the model is further increased. The effectiveness of the proposed method is validated by some flight data. By utilizing the obtained model, a flight controller is designed and then employed to control the helicopter. The experimental result further demonstrates the validity of the indentified yaw model.
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2015, Vol. 28 
