MODELING AND CONTROL OF DYNAMIC POSITIONING SYSTEM USING FULL AND PARTIAL ACTUATOR

• Main Author: Teguh Subarkah, Mochamad
• Format: Theses
• Language: Indonesia
• Online Access: https://digilib.itb.ac.id/gdl/view/39734
• Institution: Institut Teknologi Bandung

In a certain application, a vessel need to maintain its position and oreientation or follow a desired track. Dynamic Positioning System (DPS), a system to maintain its position and orientation using its own thrusters, is the solution of that problem. Controller design of DPS need vessel modeling. Vessel dynamic model is include thrusters dynamic model and identification of thrust against RPM using a bollard pull test. Analytical Vessel modeling is a nonlinear model with the input is force in surge and sway and moment on yaw with the output is position in surge an sway and orientation on yaw. Three kind of controllers, PD, Optimal LQ, and Sliding Mode, are proposed and tested. Besides, wind feedforward control is used on those three controllers. The Control signals are allocated to each thrusters using a Lagrangian Multipler Techinque. The simulation testing is executed on some condition, without wind, windy without wind feedforward, and windy with wind feedforward. The real experimental is run by implement the main controller on a PC. While the communication between main controller and other subsystems (Arduino Mega WiFi based), thruster controller, navigation subsystem, and anemometer subsystem, use the mosquito MQTT. DPS is tested on PT.Syergie experimental small barge, Of Course I Still Love U. The experiment is done on Situ I of ITB Jatinangor. In this study the simulation and real experiment is do on two condition, full actuators (4 thrusters) and partial, with the similar designed control system but the different is located on the number of active thruster. The simulation show LQ controller can compensate the error with a very long time compared to PD and Sliding Mode. So the real experimental is using PD and Sliding Mode Control. The real experimental shows that sliding mode with wind feedforward is perform better than PD, proven by the RMS error is smaller in surge, sway, and yaw. Beside that, the experiment shows that with the condition of 1 and 2 actuator fault, sliding mode controller can still handle the position and orientation, but with the rms error of yaw direction is increase.