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НаименованиеControl system for unmanned underwater vehicles

 

This article describes the principles for designing and implementing a multi-processor control system for a remote-controlled, unmanned, underwater vehicle, the Akva-ChS.

The Akva-ChS is designed to perform inspections and underwater work. It includes six propellers, a black-and-white and color television cameras, a jointed mechanical arm, a jointed cable-cutter, interchangeable tools and lights. Illustration depicts a 3D model of the vehicle.

The control-system components for such a vehicle are placed in different parts of the apparatus and on the ship that carries the vehicle. The control system therefore is designed as a distributed system joined in a local area network using an RS-485 interface, which allows for easy scalability and modifications, as well as minimum cabling and fast data exchange. Each part of the system fulfills its designated tasks and is connected to the operator's control panel on the ship. The control system is designed to be easy to install, configure, use and diagnose without disassembling its parts.

The control system operates over a vehicle network, control panel network and a modem channel connecting the vehicle to the control panel. The vehicle network includes two 1830BE31-chip-based microprocessor control units, a MicroPC-based central control unit and a MicroPC-based unit for sensors that determine the vehicle's position. Information is relayed in a semi-duplex packet mode with the high degree of error correction to compensate for possible interference from the operation of electrical equipment on the vehicle.

The vehicle is linked to the control panel by a "point-to-point" connection between the two MicroPC control units. The communications protocol is similar to that described above except it operates in full-duplex mode and uses a different subset of information within the packets. Signal transmit through a custom-designed modem linked to the RS-232 interface of the MicroPC.

The control panel network includes two microprocessor control units and a MicroPC-based control unit, with an RS-485 interface in semi-duplex mode and support for the protocol used in the vehicle network and the modem channel.

The multiprocessor control system includes a control unit and a central control unit. The microprocessor for the control unit is custom designed and based on the 1830BE31 microcomputer. The central control unit for higher-level computations is based on a MicroPC from Octagon Systems (USA).

The Akva's control panel uses electroluminescent displays, model EL640.480.AA1, from Planar (USA). The control panel includes a 3D, wire-frame display (based on an AutoCad model) that shows the position of the vehicle and its mechanical arms in real time.

 

A 3D model of the unmanned,
underwater vehicle

By Vitalii Veltishchev, Aleksandr Kropotov,
Yevgenii Nikolayev, Vladimir Chelyshev and Andrei Khodkin

Vitaliy Veltishchev,  Aleksandr Kropotov,  Yevgeniy Nikolayev,  Vladimir Chelyshev,  Andrey Khodkin