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A Blended Sliding Mode Control with Linear Quadratic Integral Control
based on Reduced Order Model for a VTOL System
Marco Herrera
1
, Paulo Leica
1
, Danilo Chavez
1
and Oscar Camacho
1,2
1
Departamento de Automatizaci
´
on y Control Industrial, Escuela Polit
´
ecnica Nacional,
Ladr
´
on de Guevara E11-253, Quito, Ecuador
2
Facultad de Ingenier
´
ıa, Universidad de los Andes, M
´
erida, Venezuela
Keywords:
Sliding Mode Control, LQI, Reduced Order Model, ISE Index, VTOL System.
Abstract:
In this paper, a Sliding Mode Control with chattering reduction based on reduced order model using Linear
Quadratic Integral Control as sliding surface, is implemented to One Degree of Freedom Vertical Take-Off
Landing System (VTOL). The controller performance is measured using Integral of the Square Error index
by simulation and real tests. Finally, the Sliding Mode Control with a Linear Quadratic Integral Control as
sliding surface performance for reference tracking and, robustness against VTOL system physical parameter
uncertainties and external disturbances are verified by experimental results.
1 INTRODUCTION
The Sliding Mode Control (SMC) is a robust con-
troller that deals with high-order nonlinearities, which
has been extensively studied due to its ability to re-
ject disturbances (Han et al., 2016; Nawawi et al.,
2011), and low sensitivity to uncertainties in the pa-
rameters (Prusty et al., 2016), thus it eliminates the
necessity of an accurate model of the system (Sa-
banovic et al., 2004). An LQI controller is a Linear-
Quadratic Regulator (LQR) with integral action. The
LQI advantages are: simple implementation (Carri
`
ere
et al., 2008), best possible performance according to
the minimization of an index, with a compromise be-
tween the response of the variables and the control
effort that guarantees the stability of the system (Mo-
hammadbagheri et al., 2011).
In order to achieve a robust control system with
the best performance, the advantages of the SMC and
LQI controllers can be blended in an robust-optimal
controller. In (Dong et al., 2011), an optimal slid-
ing mode control for nonlinear systems with uncer-
tainties is designed, where system stability is ensured
by minimizing a performance index. In (Teimoori
et al., 2012), an optimal sliding surface with respect a
quadratic performance index is selected for a system
where the parameters uncertainties are considered. In
(Chithra and Koshy, 2016), an integral action LQR is
combined with a robust SMC for a Twin MIMO Ro-
tor system, which is evaluated and compared with PID
and LQI controllers using simulations.
In (Zhang et al., 2014a), the combination of a
method to decouple the dynamics of the VTOL air-
craft system and a SMC is presented. The perfor-
mance of the designed controller and the tracking pro-
cess are shown with simulation results. In (Mondal
and Mahanta, 2013), a second order sliding mode
is presented and a sliding surface is designed by an
adaptive gain tuning mechanism for stabilizing a sin-
gle degree of freedom VTOL system.
In this article a robust-optimal controller based
on Sliding Mode Control with integral action (SMC-
LQI) is designed and implemented on VTOL system.
The sliding surface with an optimal criterion by mini-
mizing of a performance index is chosen. The design
of the controller is based on a reduced order model of
the VTOL system, which allows that implementation
in the real system to be simple. This paper is orga-
nized as follows. In Section I, a simplified dynamic
model of One Degree of Freedom (1-DOF) VTOL
is described. Section II, a SMC controller with re-
duction of the chattering effect is designed, where the
sliding surface is chosen via LQI controller approach.
In Section III, the performance of the controller is ver-
ified by the simulation results. In Section IV, the im-
plementation of the proposed controller on the real
platform for experimental tests are shown. Finally the
conclusions are presented in Section V.
606
Herrera, M., Leica, P., Chávez, D. and Camacho, O.
A Blended Sliding Mode Control with Linear Quadratic Integral Control based on Reduced Order Model for a VTOL System.
DOI: 10.5220/0006429606060612
In Proceedings of the 14th International Conference on Informatics in Control, Automation and Robotics (ICINCO 2017) - Volume 1, pages 606-612
ISBN: 978-989-758-263-9
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