Distributed Simulation System For Lunar Orbit Rendezvous

As one of the key technologies for lunar landing mission, lunar orbit rendezvous is drawing more and more attention. Based on the flight simulation, distributed computation and visualization technologies, concerning about lunar orbit rendezvous, the thesis designs a distributed simulation system which is suited to the space mission with multi- granularity. Platform- layer and model- layer are analyzed at the same time. The main researches and results are summarized as follows:The thesis has done the overall design of the simulation system. After analyzing lunar orbit rendezvous mission, the thesis presents some concepts about it, the practical case which is made during the demonstration, and the process of rendezvous. Lunar orbit is designed and chosen based on orbital life, orbital elements, percent time in sunlight and orbital sun angle. Model system and dataflow process are illuminated combining with mission features. The whole structure of simulation system is presented with layered-design theory. Platform- layer, model- layer and operation process are introduced completely.In the thesis, the proble m of how to design platform-layer of simulation system for lunar orbit rendezvous has been studied. Based on layered-design theory, not only hardware platform and software platform are separated, but also platform and model, model and model parameter are separated. Structure or class is adopted to memory attributes. The theory of model manage based on model-templet is proposed. Executable program, dynamic link library or matlab can be managed and driven successfully. In the aspect of virtual test manage, the way of program realization is emphasized. Test interface is laid out and associative function is introduced. XML is il ustrated as the scenario document at last.The thesis also designs model-layer of the simulation system for lunar orbit rendezvous. Describe model by uniform mathematical formulation according to model features, laying the foundation of model- layer design and simulation for mathematical model. The method of designing public data is presented, model parameter and model itself are separated. Concept of model package is proposed. Model package can contain model and model package itself to make convenience for model manage. According to lunar orbit rendezvous mission, the models of relative navigation, relative six degree of freedom(SDOF), thrust control allocation, and spacecraft relative dynamic are designed. The simulation formulation of model is presented according to mathematical formulation.The prototype of simulation system for lunar orbit rendezvous and validity of its technologies are tested. Concept, classification, construction and evolution proceeding of prototype are illuminated. Describe simulation system and model by use of Unified Modeling Language(UML). Use case diagram, class diagram, and timing diagram are used to illustrate relation about user and system, classification of model and transmission of message, circulating proceeding. Set initial parameters of simulation platform and models and test them. The simulation results verify the rightness and effectiveness of the model and platform is reasonable and feasible.The conclusions of this thesis are important references of C hinese manned rendezvous and docking Mission or lunar landing mission. The simulation system will be used to test them.