• Proceedings of the Korean Information Science Society Conference
• /
• 2004.04a
• /
• pp.916-918
• /
• 2004

본 논문에서는 3D 게임에서 다중 캐릭터의 충돌 회피에 대한 방법을 제안한다. 캐릭터는 충돌 감지 서클을 이동 상태 정보와 결합하여 다른 캐릭터와의 충돌을 예측하여, 충돌이 예측될 경우 충돌을 발생시킨 캐릭터들에 대해 초기화시에 설정된 레벨을 참고하여 충돌을 발생시키지 않는 정점을 목표지점과의 거리자를 이용하여 탐색하고 캐릭터를 이동한다. 이동한 지점은 캐릭터의 목표지정과 충돌을 발생시키지 않으며 최단 거리를 보장할 수 있는 위치이고, 이동된 지정에서 목표지정까지는 A* search를 이용하여 Pathfinding을 수행한다. 본 논문에서 제안한 방범을 적용함으로써 3D 게임에서 캐릭터와의 충돌을 회피하면서 목표지정까지 최단거리를 보장받을 수 있다.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2011.11a
• /
• pp.21-22
• /
• 2011

In this study, an analytical algorithm for collision avoidance is proposed, which is applicable to designing collision avoidance maneuvers for two encountering ships. The minimum separation distance is defined and an appropriate maneuver sequence is computed for safe and effective collision avoidance. Two approaches: 1) collision avoidance through speed change and 2) collision avoidance through heading change, are considered, and the initiation point of the avoidance maneuver is computed analytically using the geometric configuration of the two encountering ships. To verify the feasibility of the proposed algorithm, numerical simulations are carried out using a set of ship-to-ship encountering scenarios.

• Proceedings of the KSME Conference
• /
• 2005.11a
• /
• pp.186.2-186.2
• /
• 2005

• Journal of the Korean Society for Aeronautical & Space Sciences
• /
• v.36 no.10
• /
• pp.996-1002
• /
• 2008

This paper presents the development of a real-time algorithm for collision detection, collision avoidance and guidance to way-point. Three-dimensional point-mass aircraft models are used. For collision detection, time of closest point of approach(CPA) and distance at CPA are compared to threshold values. For collision avoidance, optimal acceleration input which maximizes the terminal relative distance is calculated based on optimal control theory. For guidance to way-point, proportional navigation guidance, the well-known method, is used. Two scenarios of encounter situation are illustrated to validate performance of proposed algorithm.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2004.11a
• /
• pp.89-94
• /
• 2004

Up to now a lot of the study on ship collision avoidance systems has proceeded actively. However the frequency of ship collision accidents didn't decreased. If there is collision risk in close quarters situation none the less manouvering ship for collision avoidance according to the system, only use of TCPA and DCPA as input factor for collision risk decision is not useful to avoiding collision action. For the recent 5 years by the analysis of first observation distance about approaching ship in domestic collision accidents, nearly $45\%$ of accidents is close first observation less than 2 miles. Therefor it is essential part for safety navigations to study for collision avoidance action in close encounter. In this paper, as foundation study of supporting collision avoidance manoeuvring for navigators, we proposed ship collision avoidance support model in close quarters situation through analysis of collision accidents for effective getting rid of the causes.

• Proceedings of the Korean Institute of Navigation and Port Research Conference
• /
• 2022.11a
• /
• pp.76-77
• /
• 2022

COLREGS의 규칙 17에는 피항선박만의 충돌회피동작으로 충돌을 피할 수 없을때 유지선박은 충돌을 피하기 위한 협력 행동을 취해야 한다고 명시되어 있다. 이 연구에서는 두 선박 간 충돌 시 각도별 거리(CDC)를 통해서 유지선박이 언제 충돌회피 협력 동작을 취해야 하는 시점을 제시하였다. 두 선박 간 충돌평가는 다양한 시나리오에 기반한 시뮬레이션을 통해 수행되었고, 시뮬레이션은 MMG 모델에 의해 설계되었다.

• Journal of Navigation and Port Research
• /
• v.28 no.10 s.96
• /
• pp.827-832
• /
• 2004

Up to now a lot of the study on ship collision avoidance systems have proceeded actively. However the rate of ship collision accidents hasn't decreased yet. If there is collision risk in close quarters situation in spite of maneuvering ship for collision avoidance according to the system, only use of TCP A and DCP A as input factor for collision risk decision is not useful to avoiding collision action. For the recent 5 years by the analysis of first observation distance about approaching ship in domestic collision accidents, nearly $45\%$ of accidents is close first observation less than 2 miles. Therefore it is essential part for safety navigations to study for collision avoidance action in close encounter. In this paper, as a fundamental study of supporting collision avoidance maneuvering for navigators, we proposed ship collision avoidance support model in close quarters situation through analysis qf collision accidents to effectively get rid of the causes.

• Journal of Advanced Navigation Technology
• /
• v.16 no.2
• /
• pp.197-203
• /
• 2012

In this paper, study the substantial issues which occurs upon free flight environment by performing separation assurance under multiple conflict(over 3 Aircraft), recovery en route under the terms of time constrains and fixed way point after the conflict avoidance, correlations between conflict detection distance and separation assurance by utilizing Autonomous flight algorithm. Result of this experiment demonstrates that the extension of detection distance is advantageous to solution of separation assurance and enhancing of flight efficiency, choose to maneuver by applying time constrain terms and fixed way point according to the situation of conflict prediction in case of recovery maneuver after the conflict avoidance. And separation assurance can be solved by applying 2 degrees or more of bank angle. When choosing the optimal bank angle could be drastically improved flight efficiency.

• Journal of Navigation and Port Research
• /
• v.43 no.6
• /
• pp.377-383
• /
• 2019

Naval ships that are navigating always have the possibility of colliding, but there is no clear maneuvering procedure for collision avoidance, and there is a tendency to depend entirely on the intuitive judgment of the Officer Of Watch (OOW). In this study, we conducted a questionnaire survey when and how to avoid collision for the OOW in a Constant Bearing, Decreasing Range (CBDR) situation wherein the naval ships encountered obstacles. Using the results of the questionnaire survey, we analyzed the CBDR situation of encountering obstacles, and how to avoid collision in day/night. The most difficult to maneuver areas were Pyeongtaek, Mokpo, and occurred mainly in narrow channels. The frequency appeared on average about once every four hours, and there were more of a large number of ships encountering situations than the 1:1 situation. The method of check of collision course confirmation was more reliable with the eye confirmation results, and priority was given to distance at closest point of approach (DCPA) and time at closest point of approach (TCPA). There was not a difference in DCPA between the give-way ship and stand-on ship, but a difference between day and night. Also, most navigators prefer to use maneuvering & shifting when avoiding collisions, and steering is 10-15°, shifting ±5knots, and the drift course was direction added stern of the obstacles to the direction of it. These results will facilitate in providing officers with standards for collision avoidance, and also apply to the development of AI and big data based unmanned ship collision avoidance algorithms.

• Journal of Navigation and Port Research
• /
• v.45 no.6
• /
• pp.298-305
• /
• 2021

Identifying the effect of turning characteristics on collision avoidance for Maritime Autonomous Surface Ships (MASS) can provide a key to avoid the collision of MASS. The purpose of this study was to derive a method to identify the effect of turning characteristics, which can be changed by various rudder angles and the ship's speed, on collision avoidance. The turning circle was observed using a mathematical model of a 161-meter-long ship, and it was analyzed that the turning circle had an effect on collision avoidance through numerical simulations of collision avoidance for four collision situations of two ships. The evaluation results using the two variables, the minimum relative distance between two ships and the minimum time at the minimum relative distance, demonstrated that the rudder angle has a major influence on the change of the minimum relative distance, and the ship's speed has a major influence on the change of the minimum time. The evaluation method proposed in this study was expected to be applicable to collision avoidance as a measures in remote control of MASS.