Distributed Flight Simulation Study

Based on the flight simulation, distributed computation and visualization technologies, this thesis designs and develops a distributed simulation system called Distributed Flight Simulation Environment (DFSE), and investigates the theories and technologies involved in the procedure of devising its application subsystem, distributed infrastructure kernel subsystem and interactive interface. As a general-purpose distributed system, DFSE is suited to the flight simulation with fine granularity models of an aerospace vehicle, such as a missile, a rocket or a space station, and so on.Benefited from the popular mode of client/server, middle-ware technology and layered-design theory in distributed systems, DFSE is developed by adopting the object-oriented software design method according to the basic requirements and characteristics of flight simulation. DFSE realized the separation of the simulation system from the computer network system, the application-layer subsystem from the kernel infrastructure subsystem, simulation task models from the simulation software system, and simulation algorithms from the realization of simulation models. As a result, DFSE has many excellent characteristics, such as the capability of platform-independence, reusability, reliability, portability and scalability. The main contributions of this thesis are summarized as follows:1. After analyzing deeply and digesting the distributed processing and flight simulation technologies embedded in our developed projects, the thesis presents a scheme of realizing data exchange by the mechanism of shared memory in a distributed flight simulation system based on the characteristics of simulation models of the target system.2. The thesis constructs a kind of distributed architecture and software environment of the flight simulation application system called DFSE. According to the characteristics and requirements of a flight simulation system, the layered architecture of DFSE is established by taking advantage of advanced simulation theories and simulation technologies.3. The thesis accomplishes the theoretical and methodological research as well as software development of the kernel infrastructure subsystem of DFSE. A type of communication middle-ware is developed to enable DFSE to work across several network platforms. In order to share the simulation data transparently among the nodes in a simulation system, the thesis introduces the conception of logic shared memory technology, and investigates its basic theory, constructing method, working mechanism and classifying technique. An envents-based and time-based scheduling subsystem is developed to control the running of the distributed flight simulation system, and a group of system services of DFSE are implemented in the paper, too,4. The thesis designs and develops the application-layer architecture andsubsystem of DFSE by utilizing the layered-design theory. Moreover, the thesis researches the simulation theories and technologies about the distribution capability of simulation tasks, the principle of task decomposing and deploying, the technology of the parameter distribution and simulation modeling, and so on.5. The thesis analyzes many kinds of factors that would weaken the performance of DFSE down, and presents a set of methods to improve it, and also introduces some methods and quantitative indexes to evaluate it.6. The DFSE system and the validity of its technologies are tested by distributed simulation experiments on a typical project simulation task, which shows that the software product is easy to use and powerful.Based on system simulation and computer network technologies, distributed simulation technology is developing into one of the main approaches to simulating a large-scale complicated system. DFSE, which is an integrated system implemented by utilizing the distributed simulation technologies, will be widely used to meet the need of flight simulation in the demonstration, design or experiment aspect of an aerospace vehicle and other...