The project titled "Modal Analysis of a Satellite Bus Structure" involved a comprehensive study of the dynamic behavior of a satellite’s primary support structure, known as the satellite bus, through Finite Element Analysis (FEA). The process began with the development of a detailed 3D CAD model in Ansys SpaceClaim, where the geometry of the satellite bus—including structural panels, mounting brackets, internal frames, and load-bearing interfaces—was created to reflect a realistic design representative of mid-sized satellite platforms. Simplifications were applied to non-critical features such as fillets and fasteners to reduce computational complexity without compromising structural fidelity.
Once the geometry was finalized, the model was imported into Ansys Mechanical for preprocessing and simulation. A material model was assigned assuming aerospace-grade aluminum alloys for the main structure, owing to their high stiffness-to-weight ratio and widespread use in satellite construction. Boundary conditions were applied to simulate fixed constraints at launch vehicle mounting points, and mass representations were included to account for subsystems like payloads, batteries, and avionics, which influence the system’s inertia distribution. The structure was discretized using a mesh of second-order tetrahedral elements, refined particularly at regions of high stress concentration and interface transitions to ensure numerical accuracy.
Modal analysis was then performed to extract the natural frequencies and corresponding mode shapes, which are critical for evaluating the structure’s response to dynamic loads such as launch vibrations, acoustic excitation, and in-orbit disturbances. The first ten modes were examined in detail, as these typically govern the rigid body and fundamental bending/twisting behavior. The results were assessed against industry design guidelines to ensure that the fundamental frequencies did not fall within the excitation frequency range of the launch vehicle, thereby avoiding resonance. The study provided valuable insights for optimizing the satellite structure’s mass and stiffness distribution, improving vibrational robustness, and guiding future structural enhancements for space-readiness.
The project highlighted the critical role of modal analysis in the early stages of satellite structural design, ensuring vibration compatibility with launch environments. It emphasized the importance of accurate mass distribution modeling and careful boundary condition definition when simulating real-world dynamic responses. Key takeaways included a deeper understanding of how geometric complexity and subsystem placement influence mode shapes, the effectiveness of mesh refinement in capturing structural behavior, and how simulation tools like Ansys Mechanical can preemptively identify design risks before costly prototyping or testing. The experience reinforced the necessity of integrating CAD and FEA workflows for efficient, reliable satellite design in the aerospace industry.