Research On Launch And Movement Characteristics Of Variable Structure Micro-spacecraft

Variable structure micro-spacecraft(VSMS) has a sort of expansion mechanism, which spread to prescriptive work structure from the state of folded style. The aircraft will keep fixed structure during free flight process. In this dissertation, aiming as characteristics of structure and performance, a novel method using theory analysis, numerical simulation and experiment is applied to investigate systemically the process of releasing-launching and free flight. The operational principle、kinetic characteristics and dynamic property of VSMS was obtained. The major works were done in this thesis as follows.1. The central work system of VSMS includes power installation、axial expansion mechanism and radial expansion mechanism, et al. The structure design is completed. The structure form and operational principle of each subsystem are analysed. Mission demands and primary technology insex are introduced. Time sequential work flow scheme is set up, each time sequential operation mission is analysed systemically, the time sequential operation characteristics of VSMS are obtained.2. The interior ballistic test of solid rocket motor and ground releasing-launching test of VSMS are designed, the operating performance on power installation and releasing-launching process are researched. The test process is recorded by high-speed video recorder, and the data is gathered by multichannel instantaneous recorder. The effect of igniting charge mass on interior ballistic performance of solid rocket motor and motion performance under releasing-launching are discussed elementarily. Expanding course of power installation and the system during releasing-launching phase is achieved. The valuable data is offered for numerical simulation and engineering project.3. The mathematical models for subsystem are established. According to numerical simulation, the subsystem motion laws and performance characteristics are analysed. The model of power installation is educed with interior ballistics and designed theoty of solid rocket motor. The numerical study with different igniting charge mass of releasable solid rocket motor. Veriety laws on pressure and thrust of solid rocket motor is obtained by comparing with test data. The mode model of flexible body is adopted; a dynamic model of expansion mechanism is established with continuous inpact method. The performance characteristics and dynamic response are researched with simulation.4. VSMS experiences two important structure variety of axial and radial expansion, contact-impact accompanies variable process, and the system motion development is complicated. The system structure transformation and dynamic development is described based on mulrybody systems method during releasing-launching phase. The VSMS model of releasing-launching phase is established, orbital and attitude movement of ideal and nonideal operating condition is studied for running a circle. The motion characteristics and dynamic response are obtained at the stage by numerical and test study, attitude movement under different initial conditions is discussed, and the work attitude laws is summarized.5. For research the problem about energy tardo loss in the long running period, a VSMS energy dissipation model is enduced using energy dissipation coefficient. Some conditions about orbit and attitude movement with linearity constant coefficient and nonlinear parabola style coefficient is discussed in given hypothesis, and stable work time of VSMS is forecasted.This research provides an approach to study dynamic structure variety of spacecraft. It also can supply vital reference to the structural engineering design and optimization as well as the programming of attitude control.