Pitch control simulation for underwater pipe platform with rise and dive functions

Abstract

A towed underwater pipe platform with a displaceable air chamber was modelled and simulated with 2 control systems. Fuzzy Logic and Proportional-Integral-Derivative (PID) control algorithms were coded and implemented onto the simulated model, with the goal of keeping the platform horizontal under dynamic conditions. The performance of each control system was observed by simulating the behaviour of the platform with an initial displacement and plotting the platform's angular displacement against time. A complete evasive maneuver sequence with rising and diving functions was simulated and pitch control was observed. The results from the initial angular displacement simulation show a relatively better transient response and settling time from fuzzy logic controller, at the cost of minute oscillations about the desired output. The PID controller showed more stable response during the neutral phases. Changes in the system conditions during the rising and diving phases had very little impact on the fuzzy logic controller's ability to maintain horizontal orientation where as the PID controller suffered much more noticeably. These results show that the fuzzy logic controller performs optimally as a control system for the underwater platform that can rise and dive. These results can be used to improve the stability of underwater imaging devices while preventing information loss and damage due to collisions.