Coordination control of multiple autonomous Underwater vehicles with communication Constraints

Abstract

An autonomous underwater vehicle is a submersible undersea vehicle, equipped with newlinesensors, actuators and power supply. It is controlled by an on board computer to newlineperform assigned tasks. There are number of motion control paradigms of AUVs such newlineas navigation, path following and co-operative motion. Some of interesting applications newlineof a group of AUVs deployed in cooperative motion are pipeline inspections in gas and newlineoil industries, oceanographic observations, bathymetric surveys, military usages, rescue newlineof lost man-made objects, high resolution seabed inspection, mapping, commercial newlinesurvey and neutralization of undersea mines area. Cooperative motion can be newlineaccomplished through Formation Control or Flocking Control of multiple AUVs. newlineResearch on formation control of AUVs is quite challenging owing to their specific newlineapplications, control and communication issues involved. In an acoustic underwater newlinemedium, inter-vehicle communication is challenging for a group of AUVs deployed in newlineformation because of constraints such as low data rate, packet delays and dropouts. newlineVarious control complexities are also encountered for formation control of AUVs due to newlinecommunication constraints in underwater medium, uncertainties in its parameters and newlinedynamics in presence of hydrodynamic ocean currents and disturbances. Thus, there is newlinea great challenge to develop efficient control algorithms such that path tracking and newlinecooperative motion can be achieved effectively. Sliding mode control is a very successful robust control approach to achieve desired newlineperformance of a system with uncertainties. Therefore, this thesis first develops a newlineSliding mode controller for achieving formation control of a group of AUVs as there are newlinenumber of uncertainties encountered in AUV dynamics. Subsequently for achieving newlinecoordinated motion tracking of a group of autonomous underwater vehicles with newlinevariable added mass in presence of communication constrains, an adaptive sliding mode newlinecontrol scheme is developed. Further, to resolve the constr