Application of VR technology in Ship trajectory Analysis - Dr. Xu Cuidong
Abstract: Ship transportation is widely used in today's industrial transportation, and the role of ocean transportation ship trajectory analysis is very obvious. At present, ship trajectory can be analyzed by three common methods: traditional probabilistic false method, Bayesian network statistical method and neural network statistical method. It is found that environmental factors and human factors affect the progress of the work. In order to reduce the influence of the above factors, the research work through real-time monitoring of ship position, precise control of ship trajectory, virtual reality technology to extract navigation information, effectively control navigation risks, realize the optimization of ocean transport ship trajectory analysis work, and help the rapid development of ship transport and ocean transport industry.
Key words: Virtual reality; Ocean transportation; The ship; Path analysis
Track refers to the recorded sequence of location and time that an object passes through in the process of moving. Ships move on water with weak maneuverability and low controllability. Trajectory analysis refers to analyzing the moving position of a moving object based on existing data and mathematical algorithms by certain means. In the 20th century, the technology was limited, and the recording of ship motion track could only rely on active observation of small samples, such as the observation ship or radar taking pictures at regular time, so as to plot the ship's motion track. In recent years, with the development of intelligent technology, ship trajectory no longer depends on manual drawing, but through various algorithms to set its trajectory in advance, and there are new definitions in position monitoring and risk prevention. By using manual technology, the concrete numerical results of nonlinear control parameters are calculated, and the ship trajectory is controlled precisely. Based on the basic navigation coefficient combined with the theory of inertia Angle and momentum, the network information main body is connected and processed by multi-equipment structure, so as to solve the problem of unclear position in ship's navigation path. Based on kalman filter theory, polynomial Kalman filter is established to predict the actual ship navigation trajectory, and virtual reality technology is used to control the risk of ship navigation. Based on the above background, by exploring the research progress of ocean transport ship trajectory analysis, we can better understand the current scientific and technological progress and development prospects of ocean transport ship trajectory, and provide infinite possibilities for future technology extension and new field development.
1 ship track analysis method
Data acquisition, data cleaning, data storage, operation algorithm, trajectory analysis and selection, and result output are six indispensable steps in the course of ship trajectory analysis. In general, data acquisition is to collect ship track by artificial and radar observation. Data cleaning refers to the removal of noise and repetition or non-important parts in the collected data. Data storage means to put the cleaned data into the database, which can not only save the data but also facilitate extraction in the future. The selection of trajectory analysis method is from the perspective of similarity measurement and exploration of trajectory analysis strategy. Result output refers to the output of the final result in the form of data or pictures. At present, common ship trajectory methods include traditional probability hypothesis method, Bayesian network statistical method and neural network statistical method. Probabilistic hypothesis method is a traditional statistical method, that is, the trajectory is assumed by ship navigation law. The Bayesian network is a model that uses nodes to represent objects and can connect the relationship between objects, so that people can have a better understanding of ship track in a graphical way. Neural network is a machine learning method, which guides the machine to learn through artificial intelligence. It is similar to a program code, and has good application in nonlinear trajectory research.
In the environment of increasing trade demand, the demand for Marine transportation is increasing day by day, the pressure and burden of Marine transportation is also increasing, and the diverse environment has become a severe test. There are many causes of abnormal trajectory in ship sailing, such as hardware failure, poor weather conditions, and even some unexpected factors, such as sudden terrorist incidents. Therefore, it is an urgent need of Marine transportation to strengthen the management of ship navigation track, ensure the safety of ship transportation and improve the efficiency of maritime traffic management. In the process of ship transportation, accurate control of navigation trajectory, real-time monitoring of ship position and effective control of navigation risks are of great significance for the realization of intelligent maritime traffic management. Ship track analysis has many shortcomings before artificial intelligence technology: 1) It is difficult to extract data, which is time-consuming and laborious because only active observation can be relied on. 2) The algorithm is single and the trajectory control is not accurate. Due to the limitation of the theoretical algorithm, the trajectory control can not be accurate, and sometimes there will be a large deviation. 3) Due to the lack of monitoring technology, navigation track is prone to frequent loss, resulting in uncertainty of ship navigation and increased risk of ship navigation.
2. Research progress of ship trajectory analysis
2.1 Real-time monitoring position
Traditional OpenGL will use inverse solution algorithm to determine the ship's navigation Angle, which is difficult to accurately ship's navigation Angle, and the actual Angle will exceed the predetermined Angle range. Aiming at the ship's trajectory loss in the navigation process, a feasible method is proposed according to ship's trajectory analysis. Import the ship track, observe the existing data according to the track recorder, confirm the general navigation trend through the calculation formula, deploy the data node position, check whether the navigation import track is complete, and finally import the navigation track for virtual processing, which can accurately determine the ship navigation Angle degree, as shown in Figure 1.
Figure 1. Schematic diagram of navigation track import
In this way, the original intention of accurate real-time monitoring of the ship's position in the navigation track can be realized to avoid the problem of track loss in the navigation process.
2.2 Precise control of trajectory
Increases as the sailing time, ship's host for trajectory control ability will decline gradually, quickly reduce ship planning ability, according to the characteristics of ship it in the ship trajectory analysis is put forward under the action of artificial intelligence technology, adjust the pseudo inverse coefficient of ship track, by controlling the regulator, on the basis of TLC design idea, Control the ship track object to get the track control command. With the change of the final command, the sailing route of the ship will also change, so as to achieve the purpose of precise control of the ship's sailing path. According to the differential algebra theory, through the support of artificial intelligence, control parameters, nonlinear build complete the course of the controller, and under the action of artificial intelligence, realize the relevance between the host and use of digital media technology to build virtual chip, virtual chip control with strong leadership, equivalent to the human brain, Can issue instructions to other components and control other components. This mode greatly improves the precision of ship trajectory control.
3 virtual reality technology to extract navigation information control risk
Due to the ship under the influence of some factors of force majeure, such as wind speed, and the size of the waves, such as size, which can lead to ship the actual trajectory and expected a deviation, combined with the maritime traffic density increasing, the ship trajectory burden also will increase, in order to avoid a maritime traffic accident, ship trajectory analysis by using virtual reality technology is put forward, According to the longitude and latitude information of the ship at sea and the probability of the ship's track points appearing in the sea route, the characteristics of the ship's track can be extracted, and the influence of the sea environment on the ship's navigation can be eliminated by measuring the similarity of the ship's track structure, so as to reduce the risk of the ship's navigation at sea. At the same time, the general information of the route is extracted in advance by using the SHIP AIS data, which provides a lot of information for the simulation of the ship's trajectory. Combined with the characteristics of the ship's trajectory, the ship's trajectory analysis can be carried out more easily. Experiments show that the collision probability of virtual reality is lower than that of traditional ship trajectory simulation under low risk environment or high risk environment. However, at present, the risk source information and data materials are usually planar and literal. In specific work, managers cannot form an intuitive understanding of the location, appearance and possible accidents of risk sources. Through the application of virtual reality technology, the environmental risk source evaluation management system can be made on the basis of the previous encountered, based on which to realize the effective evaluation of risk sources, and then grasp the intuitive and accurate characteristics of the evaluation results. In government work, the quantity, type, appearance, location and consequence of risk sources can be comprehensively mastered by using this method, laying a good foundation for follow-up related work.
Through the current ship trajectory analysis research, the importance of ship trajectory analysis and the development status and trend of several major aspects in this field are explored, which provides support for the field direction and technical innovation of ship trajectory analysis research in the future. This paper is a little inadequate in the comprehensiveness of ship trajectory analysis, and only expounds the current research progress from several main aspects, which is a little one-sided. Based on the current status of ship trajectory analysis, a relatively perfect system has been established in terms of accuracy, integrity and stability. In future ship trajectory analysis and research, the shortcomings in current technology can be improved and new fields can be developed.
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