The Development of Neural Network Based System Identification ...

2.4 AUTOMATIC FLIGHT CONTROL SYSTEM 37
HOVER
u = 3 m/s
u = 6 m/s
u = X m/s
Figure 2.7
An overview of gain scheduling control approach.
of control methodologies were proposed to address helicopter control problems, which
vary from the classical control method to learning based control.
Detailed review
on the existing control methodologies applied to the unmanned helicopter system is
given in Kendoul [2012], Nonami [2010], Valavanis [2007]. These flight controllers are
generally classified in three broad categories such as linear flight controllers, model
based non-linear controllers and learning based flight controllers.
The linear controllers are currently the most favoured methods used by military
and industrial research communities due to the simple implementation and intuitive
control system structure. There exist many available tools that can be used to refine the
controller’s gains and to analyse their performance and robustness. Moreover, the linear
controllers have been successfully implemented in UAS applications and have been
shown to be effective in numerous flight tests [Mettler, 2003, Valavanis, 2007, Saripalli
et al., 2003, Amidi et al., 1999, Kendoul, 2012]. Recent research on helicopter UAS has
focussed on the use of linear control theories such as Linear Quadratic Regulator [Shin
et al., 2005, Nonami, 2010, Bergerman et al., 2007], H ∞ control [Civita, 2003, Walker,
2003] and Gain Scheduling control [Antunes et al., 2010].