An Automatic Control Method for the Position and the Attitude of an Underwater Vehicle (Part 2)

Underwater vehicle speed control methodology method is the focus of research in this study. Driven by a hydraulic flexible traction system, the underwater vehicle advances steadily on underwater guide rails, simulating an underwater environment for the carried device. Considering the influence of steel rope viscoelasticity and the control system traction structure feature, a mathematical model of the underwater vehicle driven by hydraulic flexible traction system is established. A speed control strategy is then proposed based on the sliding mode variable structure of fuzzy reaching law, according to nonlinearity and external variable load of the vehicle speed control system. Sliding mode variable structure control theory for the nonlinear system allows an improved control effect for movements in “sliding mode” when compared with conventional control. The fuzzy control theory is also introduced, weakening output chattering caused by the sliding mode control switchover while producing high output stability. Matlab mathematical simulation and practical test verification indicate the speed control method as effective in obtaining accurate control results, thus inferring strong practical significance for engineering applications.

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Implementation of Intelligent Control System for Autonomous Underwater Vehicle

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.701-702.704 ◽

2014 ◽

Vol 701-702 ◽

pp. 704-710 ◽

Cited By ~ 2

Author(s):

Viacheslav Pshikhopov ◽

Yuriy Chernukhin ◽

Viktor Guzik ◽

Mikhail Medvedev ◽

Boris Gurenko ◽

...

Keyword(s):

Control System ◽

Motion Control ◽

Intelligent Control ◽

Autonomous Underwater Vehicle ◽

Control Method ◽

Underwater Vehicle ◽

Intelligent Control System ◽

Azov Sea ◽

Complex Simulation ◽

Point To Point

This paper introduces the implementation of intelligent motion control and planning for autonomous underwater vehicle (AUV). Previously developed control system features intelligent motion control and planning subsystem, based on artificial neural networks. It allows detecting and avoiding moving obstacles in front of the AUV. The motion control subsystem uses position-trajectory control method to position AUV, move from point to point and along given path with given speed. Control system was tested in the multi-module simulation complex. Simulation showed good results – AUV successfully achieved given goals avoiding collisions not only with static obstacles, but also with mobile ones. That allows using the proposed control system for the groups of vehicles. Besides simulation, control system was implemented in hardware. AUV prototype passed tests in Azov Sea and proved its efficiency.

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Real-Time Monitoring and Automatic Control for Aerosol Cultivation of Lettuce

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.678.299 ◽

2014 ◽

Vol 678 ◽

pp. 299-304

Author(s):

Bao Guo Yao ◽

Zhe Feng Zhang

Keyword(s):

Control System ◽

Automatic Control ◽

Real Time ◽

Nutrient Solution ◽

Control Method ◽

Ph Value ◽

Agricultural Science ◽

Monitoring And Control ◽

Real Time Monitoring ◽

And Control

The automatic monitoring and control method for aerosol cultivation of lettuce was proposed by real-time monitoring and automatic control of the cultivation environment, on-line detection and automatic control of nutrient solution, and the combination of field control and remote control, which has realized the intelligent management of aerosol cultivation of lettuce based on plant factory. The monitoring and control system of aerosol cultivation, the control model for the spray frequency of nutrient solution and the fuzzy control method for the pH value control of nutrient solution were introduced. The control system has been applied in the agricultural science and technology park, and the results show that the aerosol cultivation of lettuce has advantages over the traditional method.

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Design of Robust Nonlinear Optimal Controller for Underwater Vehicle to Move in Depth Channel Using Gradient Descent Method with Systematic Step Selection

Applied Mechanics and Materials ◽

10.4028/www.scientific.net/amm.704.320 ◽

2014 ◽

Vol 704 ◽

pp. 320-324

Author(s):

Marzieh Ahmadi ◽

Abolfazl Halvaei Niasar ◽

Alireza Faraji ◽

Hassan Moghbeli

Keyword(s):

Gradient Descent ◽

Degrees Of Freedom ◽

Control Method ◽

Parametric Uncertainty ◽

Underwater Vehicle ◽

Descent Method ◽

Optimal Controller ◽

Gradient Descent Method ◽

Six Degrees Of Freedom ◽

Step Selection

This paper proposes the design of a robust nonlinear optimal controller to move the underwater vehicle in the depth channel using gradient descent method. A nonlinear model with six degrees of freedom (6-DOF) has been extracted for the underwater vehicle. To selection of the model and design of controller, conventional assumptions used for other controllers have not been considered and the developed controller can be implemented via at least assumptions. In presented control method, systematic step selection for solving of the algorithm has increased the rate of convergence significantly. The performances of the proposed robust controller for moving in depth channel with considering of parametric uncertainty for the model have been confirmed via some simulations. The results show the desirable performance of developed controller.

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