Showing papers by "Xiumin Chu published in 2016"
TL;DR: In this paper, a Bayesian Network-based methodology is proposed to extract moving vessels from a plethora of blips captured in frame-by-frame radar images, where the inter-frame differences or graph characteristics of the blips, such as velocity, direction, and shape, are quantified and selected as nodes to construct a Directed Acyclic Graph (DAG), which is used for reasoning the probability of a blip being a moving vessel.
27 citations
Patent•
15 Jun 2016
TL;DR: In this paper, a model ship based autonomous navigation control simulation system and method of an under-actuated unmanned ship is presented, where an environment sensing sub system, a path programming sub system and a motion control sub system are combined to calculate the rudder angle and propeller rotating speed instruction needed in next navigation of the ship and control a steering engine and a propeller.
Abstract: The invention provides a model ship based autonomous navigation control simulation system and method of an under-actuated unmanned ship The whole system is arranged on a model ship, and the model ship is arranged in a simulated navigation channel; the system comprises an environment sensing sub system, a path programming sub system and a motion control sub system; the environment sensing sub system collects the navigation state of the model ship and simulates environment factor information; according to the navigation state of the model ship and the simulated environment factor information, the path programming sub system carries out navigation programming to obtain the tracking route, the set speed and the set course; and the motion control system combines a course tracking model, a path tracking model, the route deviation, the course deviation and the speed deviation to calculate the rudder angle and propeller rotating speed instruction needed in next navigation of the model ship and control a steering engine and a propeller According to the invention, simulation experiments are carried out on the model ship, an instance is provided for operation and control experiments of large ships, important guarantee is provided for safe navigation of large ships in inland rivers, and the system reduces the difficult and cost of experiments of the large ships
21 citations
Patent•
15 Jun 2016
TL;DR: In this paper, an under-actuated unmanned ship formation structure based on model ships is presented, which consists of multiple model ships that are arranged in a simulated navigation channel, and the simulated navigation channels includes simulated environment factors; one model ship serves as a master ship, and other model ships serve as slaves ships.
Abstract: The invention provides an under-actuated unmanned ship formation structure based on model ships. The structure comprises the multiple model ships that are arranged in a simulated navigation channel, and the simulated navigation channel includes simulated environment factors; one model ship serves as a master ship, and other model ships serve as slavery ships; the master ship is provided with a master ship simulation control system, the slavery ships are provided with a slavery ship simulation control system, the shore base is provided with a positioning information monitoring system, and the master ship simulation control system, the slavery ship simulation control system and the positioning information monitoring system are connected via network; and the positioning information monitoring system comprises a shore-based camera and a computer, the shore-based camera is used to capture marker lamps on the model ships and thus carry out image identification positioning on all the model ships, and the computer is used to identify and process images collected by the shore-based camera and obtain positioning information of the master and slavery ships. According to the invention, the difficulty and cost of large ship formation experiments are reduced, an instance is provided for operation and control of the large ship formation, and important guarantee is provided for tasks of safe ship formation navigation.
8 citations
21 May 2016
TL;DR: Field experiment shows that the proposed model is capable of predicting the median attenuation of AIS more accurately at mountainous waterway than pre-existing models.
Abstract: The AIS, Automatic Identification System, is a communication system designed for exchanging information between vessels. While analyzing the reliability of the data link of AIS, it is quite important to known the distribution of field strength of AIS signal. However, empirical models designed for predicting the median attenuation of AIS signal only effective at sea and coastal waterway. As the AIS is introduced to mountainous waterway, the environmental conditions are extremely different from the sea, hence the pre-existing empirical models are no longer competent. To address this problem, we designed experiments conducted at mountainous waterway, to explore the practical attenuation of AIS signal. Then, based on the experimental data, correlation between the attenuation and the transmitting distance of AIS signal was figured out. Consequently, with the correlations, it is possible to develop a new model by curve fitting. Field experiment shows that the proposed model is capable of predicting the median attenuation of AIS more accurately at mountainous waterway than pre-existing models.
1 citations