Research And Implement Of Safety-oriented Distributed Simulation System

At present,the road safety evaluation is carried out by road traffic accident analysis and research,the method can not be used to the uncompleted road and the collection of accident data is a considerable degree of difficulty.The purpose of the research is to build a distributed interactive virtual simulation system on the road environment and driving environment,using data acquisition method to obtain the necessary experimental data,through the analysis of experimental data to conduct a safety evaluation.Because of safety-oriented software system to assess the scene of the "realism" have high demands,so the need for the original visual system improvements.The use of multi-channel technology will be the expanse the single-channel visual system to multi-channel visual system,thereby increasing the scope of the driver's vision to improve the system of "immersion",improve the authenticity of the simulation of driver's perception in real environment and the credibility of the safety evaluation.The safety-oriented distributed simulation system needs to simulate the interaction between vehicles in real environment,so the need to collect and exchange data between multiple nodes,which is real-time synchronization between nodes of simulation.In this system,the synchronous design to the two main areas:clock synchronization and data synchronization.Clock synchronization is implemented by transmit control information between nodes;the goal is to have the same local time among the nodes and facilitate system control and data collection.Data synchronization is implemented by exchange the control and status information between nodes under the certain control strategy,and corresponding entity node status on different node.For data exchange and synchronization needs,the thesis design and implementation of reliable UDP-based transport mechanism.The mechanism is based on the UDP protocol to increase the response mechanism,retransmission and confirmation mechanism,packing/unpacking mechanism,in order to achieve reliable transmission of information. Through requirement analysis of traffic safety evaluation,extracting the parameters needed for the safety evaluation,and designing method of the data collection to meet the requirements of the system.With database design technology,the experimental data can be stored in the database,easy for data analysis after experiment.