|
|
Robust Adaptive Horizontal Vibration Isolation of Towed Seismic Streamers
LIU Tao (刘 涛), ZHANG Wei-jing (张维竞), MA Jie (马 捷)
2012, 17 (1):
31-039.
doi: 10.1007/s12204-012-1226-8
Abstract: The horizontal vibration of towed seismic streamers is a main reason for efficiency reduction of the
seismic survey and tail tangling. A vibration suppression scheme of towed seismic streamers is investigated in
this paper. The towed seismic streamer is divided into two spans, a controlled span, i.e., the low tension span,
and an uncontrolled span, i.e., the high tension span, by a bird. The system model includes a hyperbolic partial
differential equation with variable coefficient describing the towed seismic streamers, and an ordinary differential
equation describing the dynamic of bird. Robust based-model knowledge and adaptive controllers, based on the
Lyapunov method, are designed to isolate the vibration of towed seismic streamers caused by the course deviations
of towing vessel, the variations of towing vessel velocity and the variations of towed seismic streamer density. The
robust based-model knowledge and adaptive controllers exponentially and asymptotically drive the span-towed
seismic streamer displacement to zero, respectively. A finite difference scheme is used to validate the efficiency of
the control law. The proposed controller can isolate effectively the disturbance originated from the towed vessel,
and can provide the improved damping but not sacrifice the isolation performance. The adaptive scheme can
tolerate the lack of knowledge of some uncertain parameters and can directly execute the online adjustment of the
parameters. Meanwhile, the proposed control law is robust and can resist the model uncertainty due to parameter
incertitude, model error and unknown disturbance and so on. The control law only includes velocity and slope,
while it does not need the displacement which is difficult to measure in the practical operations. Thus it is easy
to implement.
References |
Related Articles |
Metrics
|
