Design and Development of UWE-4 : Integration of Electric Propulsion Units, Structural Analysis and Orbital Heating Analysis

After the successful launch and operation of UWE-3 in 2013, UWE-4 is the next picosatellite in the University of Würzburg Experimental satellite program. UWE-4 is first from its series to have integrated propulsion system and with a mission objective to demonstrate attitude and orbit control using the miniature propulsion system. In future, this will pave the way to perform complicated missions such as formation flying using picosatellites. Major challenge in UWE-4 is the integration of the propulsion system (which includes both thrusters and power processing unit) into the 1U CubeSat. Integrating the thruster into the Picosatellite has several constraints, few include accommodation of the system within the structure at minimum mass and volume impact, structural design to withstand the critical launch conditions.In the scope of this master thesis project, the design of UWE-3 system arrangement is studied and the regions of possible integration of thruster units are identified. The two propulsion systems considered for the UWE-4 mission are the Micro Vacuum Arc Thrusters (µVAT) developed at UniBW in Munich, Germany and the NanoFEEP (highly miniaturized Field Emission Electric Propulsion) thrusters developed at TUDresden, Germany. During design phase, different concepts are created for the CubeSat rails to integrate the thrusters and the concepts are validated against the functional requirements as well as the CubeSat design specifications. Detailed CAD designs are completed for UWE-4 satellite using SolidWorks 2014. To validate the structural design, the CAD models are then subjected to Finite Element Modeling and Analysis (structural and thermal) using Siemens NX CAE. During static Structural analysis, various loading conditions and constraints are identified and applied to the system. Later NX NASTRAN solver is used to study and simulate the impact on the UWE-4 model. Also modal analysis was performed to study the natural frequencies of the system. With the motivation to study the thermal behavior of the system in orbit, transient analysis for orbital heating was performed using NX SPACE SYSTEMS THERMAL. The solution results from both structural analysis and thermal analysis are validated for different scenarios. Based on the results the generic design is qualified and expected to serve as a platform for future missions. Validerat; 20150709 (global_studentproject_submitter)