![](bg4.png)
roll compensation. As expected from (9) and (10),
the responses exhibited the effectiveness of the roll
compensation for attenuating stabilization error due
to the gimbal kinematic coupling.
Figure 4: Stabilization error – azimuth direction.
Figure 5: Stabilization error attenuation ratio.
The stabilization error ratio which calculated
from the magnitude of error with compensation over
the magnitude of error without compensation is
shown in Fig. 5. Evidently, the error is largely
attenuated in low frequency region, and the lesser as
increasing frequency. This result is consistent with
the analytical results in (9) and (10). From the
simulation results, we can conclude the control
proposed in this paper is effective to improve
stabilization performance of OTM antenna.
5 CONCLUSIONS
In this work, an inertial stabilization control for the
LOS of an OTM antenna driven by a motor coupled
with gear and flexible driving shaft has been
addressed. In the consideration of flexibility of the
shaft, disturbance torque due to vehicle motion
coupled with gear ratio, and kinematic coupling of
the outer gimbal dynamics, a stabilization control
has been proposed. The control consists of a
conventional IPD-control, damping-control, vehicle
motion feed-forward compensation-control, and roll
motion feed-forward compensation control.
The simulation results demonstrated that the
proposed control design guarantees system stability
and effective to attenuate the stabilization error due
to the disturbance torque related to vehicle motion
and kinematic coupling.
ACKNOWLEDGEMENTS
This work was supported by Nuclear Research &
Development Program of National Research
Fundation(NRF) funded by Ministry of Education,
Science & Technology(MEST) and the Kyungwon
University Research Fund in 2011.
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