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This paper presents a novel approach based on Jacobi shape theory and geometric reduction for formation control of autonomous underwater vehicles (AUVs). We consider a three degree-of-freedom (DOF) dynamic model for the horizontal motion of each AUV that has control inputs over surge force and yaw moment. By using the Jacobi transform, the horizontal(More)
This paper presents a novel robust controller design for formation control of autonomous underwater vehicles (AUVs). We consider a nonlinear three-degree-of-freedom dynamic model for the horizontal motion of each AUV. By using the Jacobi transform, the horizontal dynamics of AUVs are explicitly expressed as dynamics for formation shape and formation center,(More)
— This paper develops a robust controller for autonomous underwater vehicles with bounded time delays, so that the AUVs form and keep a desired formation shape and track a desired trajectory. We use a six-degree-of-freedom dynamic model for each AUV to describe its motions in the three-dimensional space. We design an orientation controller based on feedback(More)
This study investigated the distribution of cadmium (Cd) and the protein level of metallothionein (MT) and examined the relationship of Cd accumulation and the MT concentration in different tissues of freshwater mussel Anodonta woodiana following Cd treatment. The mussels were exposed to Cd (4.21, 8.43, 16.86, 33.72 and 67.45 mg L-1) for 24, 48, 72 and 96(More)
We generalize the convergence, the stability and the averaged converging rate of stochastic parallel gradient descent algorithm when it is used as control algorithm for adaptive optics system in theory. Analysis results show the adaptive optics system can obtain convergence, stability and a factor of n /square root (n is the number of control parameters)(More)
In this paper, the problem how to distribute network bandwidth over a set of real-time control loops in order to optimize the total control performance in networked control systems is studied. The problem mentioned above can be divided into two sub-problems: how the control performance depends on the quality of service (QoS) of network such as sampling(More)
— A new performance metric-the gray level variance function is offered, which is merely from a gray level distorted image and without any additional optics elements. Based on Stochastic Parallel Gradient Descent (SPGD) and the gray level variance function, a high resolution imaging adaptive optics system with a 61-element deformable mirror is simulated to(More)
A model-based wavefront sensorless (WFSless) adaptive optics (AO) system with a 61-element deformable mirror is simulated to correct the imaging of a turbulence-degraded extended object. A fast closed-loop control algorithm, which is based on the linear relation between the mean square of the aberration gradients and the second moment of the image intensity(More)
Optimizing the system performance metric directly is an important method for correcting wave-front distortions in adaptive optics(AO) systems. Appropriate stochastic parallel optimization control algorithm is the key to correcting distorted wave front successfully. Based on several stochastic parallel optimization control algorithms, an adaptive optics(More)