http://nopr.niscpr.res.in/handle/123456789/43171 <b>Special Issue on Underwater System Technology</b> 2026-10-10T05:34:29Z http://nopr.niscpr.res.in/handle/123456789/43191 Title: A smart navigation and collision avoidance approach for Autonomous Surface Vehicle Authors: Mei, Jian Hong; Arshad, M. R. Abstract: Marine traffic rules play an important role for all marine vessels to reduce the collision risk, thus The International Marine Organization (IMO) defined The International Regulations for Preventing Collisions at Sea (COLREGs) in 1972. All marine crafts including Autonomous Surface Vehicle (ASV) should follow COLREGs to avoid the collision when they encounter each other at sea or other water areas. However, the target ship may be located at the position which can cause collision if the ASV is forced to make a COLREGs compliant evasive manoeuvre. Thus, the navigation system of ASV is required to have the ability to identify the encounter situation and determine whether the ASV should obey the COLREGs or not when avoiding the target ship. To perform smart navigation and collision avoidance, the encounter situation division diagram is combined with Artificial Potential Field (APF) as the guidance system. The simulation results illustrate that the proposed guidance system successfully achieved the navigation of ASV at open sea and avoiding collision with moving target ship for different encounter situations. Page(s): 2415-2421 2017-12-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/43190 Title: Parametric resonance avoidance of offshore crane cable in subsea lowering operation through A* heuristic planner Authors: Kang, Hooi-Siang; Tang, Collin Howe-Hing; Quen, Lee Kee; Steven, Adelina; Yu, Xiaochuan Abstract: Parametric resonance of offshore crane cable was predicted by using Mathieu equation to provide structural safety prediction during subsea lowering operation. This paper studied the predicting method and automatic resonance avoidance of offshore crane cable to complement the safety management during subsea lowering operation. The offshore crane cable was modeled as a tensioned long cylindrical structure and Mathieu instability coefficients were utilized to predict the dynamic instability of the structure. Numerical analyses were conducted to predict the parametric resonance of cable, evaluate the sensitivity of effective submerged length, dynamic tension variation, and plan for resonance avoidance mechanism automatically. Dynamic instability at sub-harmonic 2:1 unstable region of Mathieu stability diagram potentially creates high risk for lowering operation if the damping coefficient is low. Dynamic tension variation can cause instability of offshore crane cable during passing through wave splash zone and landing subsea payload. The reduction of axial tension variation can stabilize the dynamic of offshore crane cable. Parametric resonance of cable is also sensitive to the total payload. The findings of this paper can enhance structural integrity prediction of offshore crane cable and provide an automatic planner to the operator to avoid parametric resonance during subsea lowering operation. Page(s): 2422-2433 2017-12-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/43189 Title: A combined systematic and metaheuristic approach for cooperative underwater acoustic source localization by a group of autonomous surface vehicles Authors: Majid, Mad Helmi Ab; Arshad, Mohd Rizal Abstract: Underwater acoustic source localization is important in many underwater applications. However, due to the intensity declination of the acoustic signal as the distance from the source increases, the possibility to detect and localize the source using a single surface platform become harder. This paper presents an underwater acoustic source localization strategy by a group of autonomous surface vehicles (ASVs) using a combined systematic and metaheuristic searching methods. The proposed localization strategy consists of two phases known as a source detection phase (based on a systematic searching method) and a source tracing phase (based on a metaheuristic searching method) implemented when none of the ASVs detect the presents of the acoustic source and when at least one of the ASVs detect the presents of the source, respectively. A formation based and a Particle Swarm Optimization (PSO) is used as a systematic and metaheuristic search method, respectively. The reliability of the proposed localization strategy is demonstrated through a series of a simulation studies. Page(s): 2434-2443 2017-12-01T00:00:00Z http://nopr.niscpr.res.in/handle/123456789/43188 Title: High-gain observer-based model predictive control for cross tracking of underactuated autonomous Underwater Vehicles: A comparative study Authors: Zhang, Guangjie; Yan, Weisheng; Gao, Jian; Liu, Changxin Abstract: In this paper, a disturbance observer-based model predictive control (DO-MPC) scheme is developed for cross tracking of underactuated autonomous underwater vehicles (AUVs) under sea current disturbances. A high-gain observer is used to estimate the current velocity, external sway force and yaw torque. Based on the disturbance estimates, a nonlinear model predictive controller is designed with consideration of actuator constraints. The control inputs are solved by optimizing the future trajectories of the nonlinear system under input constraints within a certain time horizon, which are predicted by the system model with estimated disturbances. The stability of the predictive control cross-tracking system is also proved with a Lyapunor-based method. The comparative simulation results with different algorithms are provided to validate the effectiveness of the proposed method. Page(s): 2444-2451 2017-12-01T00:00:00Z