Inspection of the Underwater Industrial Objects Using AUV Based on the Method of Feature Points Video Recognition

Abstract

Automated inspection of seabed industrial equipment with the help of AUV assumes its navigational referencing to the inspection object with sub-met er accuracy. That accuracy cannot be achieved on the base of standard onboard navigation equipment. It is proposed to use the method of video recognition of feature points (FP) on the inspected equipment to solve this problem. The FPs are preliminarily determined on the models of objects and downloaded into the AUV control system in the form of three-dimensional sets (clouds). Ensuring stable high accuracy during continuous movement of AUV in inspected objects space is realized through regular updating of the coordinate referencing to the objects. The inspection procedure using this method consists of the following steps:- the AUV mission specification (including downloading the FPs descriptions),- launching the AUV and preliminary approach to the inspected objects,- determining the optimal sequence for bypassing the inspected objects,- performing the searching procedure for the next FP and navigational reference to it,- subsequent inspection of the specified fragments of equipment.At the same time, the logic of the mission execution provides for a dynamic change in the inspection plan in case of failure when any of the planned FP are detected. The paper presents the AUV control system algorithms that implement the described inspection scenario. The approach correctness was investigated using the mathematical modeling methods.