However, it can be seen that the quadrotor is being gradually
pushedbythedisturbance.Thequadrotorcontrolsystemis
intended to give results such as those shown inFigure 8.
In the second set of experiments, we added layer 3 to the
system.
The left block is the displacement control layer. It
receives position feedback and outputs the appropriate angle
(Figure 9).
Figure 10showstheinsideblockthatimplements( 26 )and
( 27 ). With the addition of layer 3 to the system, the results
depictedinthefigurewereobtained.
ItcanbeseeninFigure 11that the attitude changes to
resist the disturbance. This appropriate change in the attitude
enables the quadrotor to have drift stabilization.
The control system knows the acceleration due to the
quadrotor control position; thus, control is possible.Figure 12
shows that it is moved to a point that maintains its objective.
Figure 13showsthatitmovestoapointtomaintainits
objective even though the disturbance is very irregular. When
therearelargeangularchangesitisdesignedtomovetoa
certain point, whereas for small angular changes it is designed
to resist the disturbance.
The final experimental results show that our proposed
multilayered drift-stabilization control system can be a useful
and powerful solution for microquadrotors.
5. Conclusion
The design and implementation of mathematical modeling of
our multilayered drift-stabilization method were successful.
Each of the layers is designed separately and drift stabilization
is achieved by cooperation with each layer.
Our proposed system provides powerful solutions for
someoftheproblemsthathavenotyetbeensolved.The
system can be mounted on small vehicles and can make
the quadrotor move to its objective even when there are
irregular disturbances. The proposed control system has good
performance and is easily expandable. Therefore, it is a useful
micro-UAV control system.
However, this control system presently has an integra-
tion error. In order to overcome this limitation, we plan
to implement a process that corrects it using vision. The
system also lacks optimization, particularly in the PID term.
Therefore, we hope to conduct further studies from which
we can present optimized results that further enhance the
usefulness of our proposed control system.
Conflict of Interests
The authors declare that there is no conflict of interests
regarding the publication of this paper.
Acknowledgment
This research was supported by the Basic Science Research
Program of the National Research Foundation of Korea
(NRF) funded by the Ministry of Science, ICT & Future
Planning (Grant no. 2012006817).
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