Model description:
In 2-DOF helicopter, a coupled 2input-2output system can be achieved due to coupling between the pitch and yaw motor torques. The linear 2-DOF helicopter state-space matrices are
$$\begin{align*} A&=\left[\matrix{ 0 &0 &1 &0\cr 0 &0 &0 &1\cr 0 &0 &-{B_{p}\over J_{eq{\_}p}+m_{heli}{l_{cm}}^{2}} &0\cr 0 &0 &0 &-{B_{y}\over J_{eq{\_}y}+m_{heli}{l_{cm}}^{2}}}\right],\\ B &=\left[ \matrix{ 0 &0\cr 0 &0\cr \dfrac{K_{pp}u_{p}}{J_{eq{\_}p}+m_{heli}{l_{cm}}^{2}} & \dfrac{K_{py}u_{y}}{J_{eq{\_}p}+m_{heli}{l_{cm}}^{2}} \cr \dfrac{K_{yp}u_{p}}{J_{eq{\_}y}+m_{heli}{l_{cm}}^{2}} & \dfrac{K_{yy}u_{y}}{J_{eq{\_}y}+m_{heli}{l_{cm}}^{2}} \cr } \right], \\ C &=\left[\matrix{1 &0 &0 &0\cr 0 &1 &0 &0}\right], D=\left[\matrix{0 &0\cr 0 &0}\right], \end{align*}$$
where $\theta(t)$ is the pitch angle and $\psi(t)$ is the yaw angle. $u_p$ and $u_y$ are the control signals applied to pitch and yaw motors, respectively. The amounts of parameters used in this formula are written in the table below.
$K_pp$ | Pitch torque | $0.204$ $N.m/V$ |
$K_yy$ | Yaw torque | $0.072$ $N.m/V$ |
$K_py$ | Yaw on pitch torque | $0.0068$ $N.m/V$ |
$K_yp$ | Pitch on yaw torque | $0.0219$ $N.m/V$ |
$J_{eq_p}$ | Total pitch moment of inertia | $0.0384$ $kg.m^2$ |
$J_{eq_y}$ | Total yaw moment of inertia | $0.0432$ $kg.m^2$ |
$B_p$ | Pitch viscous damping | $0.800$ $NN$ |
$B_y$ | Yaw viscous damping | $0.318$ $NN$ |
$m_{heli}$ | Total moving mass | $1.3872$ $kg$ |
$l_{cm}$ | Centre of mass length from pitch axis | $0.186$ $m$ |
Type:
Form:
Time domain:
Linearity:
Publication details:
Title | Disturbance Rejection for a 2-DOF Nonlinear Helicopter Model by Using MIMO Fuzzy Sliding Mode Control with Boundary Layer |
Publication Type | Conference Paper |
Year of Publication | 2012 |
Authors | Zaeri, A.H., Mohd-Noor S.B., Isa M.M., Taip F.S, and Marnani A.E. |
Conference Name | Third International Conference on Intelligent Systems, Modelling and Simulation (ISMS), 2012 |
Date Published | 02/2012 |
Publisher | IEEE |
Conference Location | Kota Kinabalu |
ISBN Number | 978-1-4673-0886-1 |
Accession Number | 12616526 |
Keywords | aircraft control, fuzzy control, helicopters, MIMO systems, nonlinear control systems, robust control, variable structure systems |
Abstract | In this paper, one helicopter model with two degrees of freedom (2-DOF) is controlled by fuzzy sliding mode control with boundary layer (FSMC-BL) while exposed to disturbance. The model is a nonlinear and multi-input multi-output (MIMO) system that requires a MIMO, robust, stable, and nonlinear control to reject the disturbance. These requirements have been satisfied by SMC. In this paper, boundary layer removes the chattering phenomenon and fuzzy logic tunes the switching gains of SMC control law online. The simulation results which are achieved for step and sinusoidal disturbances applied to both pitch and yaw angles, are compared with those of PID control based on linear quadratic regulator algorithm (LQR-PID). Considerable improvement in control signal and yaw angle is observed by using FSMC-BL. |
DOI | 10.1109/ISMS.2012.129 |