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Offshore platforms' security is concerned since in 1950s and 1960s, and in the early 1980s some important specifications
and standards are built, and all these provide technical basis of fixed platform design, construction, installation and
evaluation. With the condition that more and more platforms are in serving over age, the research about the evaluation
and detection technology of offshore platform has been a hotspot, especially underwater detection, and assessment
method based on the finite element calculation. For fixed platform structure detection, conventional NDT methods, such
as eddy current, magnetic powder, permeate, X-ray and ultrasonic, etc, are generally used. These techniques are more
mature, intuitive, but underwater detection needs underwater robot, the necessary supporting tools of auxiliary
equipment, and trained professional team, thus resources and cost used are considerable, installation time of test
equipment is long. This project presents a new kind of fast wireless detection and damage diagnosis system for fixed
offshore platform using wireless sensor networks, that is, wireless sensor nodes can be put quickly on the offshore
platform, detect offshore platform structure global status by wireless communication, and then make diagnosis. This
system is operated simply, suitable for offshore platform integrity states rapid assessment.
The designed system consists in intelligence acquisition equipment and 8 wireless collection nodes, the whole system
has 64 collection channels, namely every wireless collection node has eight 16-bit accuracy of A/D channels. Wireless
collection node, integrated with vibration sensing unit, embedded low-power micro-processing unit, wireless transceiver
unit, large-capacity power unit, and GPS time synchronization unit, can finish the functions such as vibration data
collection, initial analysis, data storage, data wireless transmission. Intelligence acquisition equipment, integrated with
high-performance computation unit, wireless transceiver unit, mobile power unit and embedded data analysis software,
can totally control multi-wireless collection nodes, receive and analyze data, parameter identification. Data is transmitted
at the 2.4GHz wireless communication channel, every sensing data channel in charge of data transmission is in a stable
frequency band, control channel responsible for the control of power parameters is in a public frequency band. The test is
initially conducted for the designed system, experimental results show that the system has good application prospects
and practical value with fast arrangement, high sampling rate, high resolution, capacity of low frequency detection.
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