A Modest Numerical Simulation for Automatic Ship Collision Avoidance System to Support Green and Autonomous Shipping Concept

The development of autonomous ship is being pursued massively and significantly, either industrially, regulatory, or academic. The autonomous ship is considered to be able to significantly reduce challenges caused by unexpected errors of manual navigation (manned ship). One of the challenges for autonomous ship development is constructing an automatic ship collision avoidance system as a basic system for identifying and avoiding an obstacle object around the ship. The collision avoidance system must consider not only the position of the ship and the obstacle but also the maneuvering characteristic (ship dynamics) and control system of the ship, thereby making its numerical system more complex. This research presents a modest numerical simulation for designing an automatic ship collision avoidance system. However, the numerical model still considers the main necessary elements of the system. The numerical model includes a set of automatic guidance system, collision avoidance system, ship dynamics, and control system. Head on head, overtaking, and crossing collision scenarios are performed to investigate the numerical model. The simulation results show that the modest numerical simulation can be used to perform an automatic ship collision avoidance system in which the ship can automatically avoid a target ship considered as the ship’s obstacle in those three collision scenarios

Numerical Analysis of Floatplane Porpoising Instability in Calm Water During Takeoff

In the operation of floatplanes, porpoising must be avoided, but it is a common occurrence during takeoff, as it induces longitudinal instability and compromises the safety and comfort of passengers. The mechanism of porpoising and the factors or variables that influence the occurrence of this phenomenon are explored in this study. Based on a review of the literature, the position of the longitudinal center of gravity (LCG) and the deadrise angle were found to be the two most significant variables affecting the porpoising phenomenon. The mechanism of porpoising was simulated using a numerical model based on computational fluid dynamics (CFD). The simulation findings were then compared to the results of a related model’s towing tank experiment. With five velocity differences, a validated computational model was used to analyze the impact of LCG ordinates and deadrise angles on the frequency of porpoising. Compared to the LCG 50% length overall (LOA) configuration, the floater with an LCG 53% LOA configuration caused a higher heave porpoising amplitude by 4% for the floater with a 10° deadrise angle and 1% for the floater with a 20° deadrise angle at all speed variations. However, the pitch porpoising amplitude produced by the floater with an LCG 53% LOA configuration was found to be 4% higher than the LCG 50% LOA configuration for the floater with a 10° deadrise angle and -1% higher than the LCG 50% LOA configuration for the floater with a 20° deadrise angle. The results showed that the higher heave and pitch porpoising amplitude was generated by a low deadrise angle and a shift in the floater’s center of gravity toward the bow

Design of a Semi-Submersible Tourism Ship for Bunaken Underwater Recreation in Manado, Indonesia

With a rapid increase in various number of marine tourism destinations, especially in The Bunaken National Park with the amount of tourists that has increased throughout the year rising by 23% for domestic tourists and 12% for international tourists between 2002 and 2018. Unfortunately, to enjoy the underwater scenery of The Bunaken National Park can access by diving and snorkeling which is not all tourist can do that. Furthermore, in order to support the marine tourism industry in Indonesia, a semi-submersible tourism ship was developed with a glass at the hull's bottom based on the standard spiral design and the safety standard established by the rules so the tourists can easily enjoy the underwater ecosystem. The concept design of bottom-glass ship with trimaran hull type is offered as a problem-solving in this paper. The final design of the main dimensions are length of overall (LOA): 23,1 meters, width (B): 8 meters, Draft (T): 2.22 meters but the maximum submerged up to 2,5 meters, speed of 10 knots, and passenger capacity of 44 persons

Preliminary Study of an Integrated Calculation of Ship Strength on Tankers with Applicable Regulations

Recently, the development of the digital era has increased significantly. Industry 4.0 began to be discussed and applied in the early 21st century. Cyber-Physical systems are becoming a trend in current technological developments. Several technologies in Industry 4.0 are being applied, such as the internet of things, cloud computing, automated simulation, intelligent robots, big data analysis, augmented reality, and additive manufacturing. The shipyard industry is one industry that must be able to adapt to keep up with technological developments. In the ship's preliminary design stage, the strength calculation process that refers to certain regulations has an important role in the design process. The integrated calculation system will make working easier for a naval architect. This paper aims to conduct an initial study in calculating ship strength integrated in real-time with the regulations that govern it. This study produces an idea to integrate the calculation of ship strength with regulations from a class society that continues to grow. The research is expected to provide further development to assist in the preliminary design process that provides efficiency and more accurate monitoring of results