Comparative Study of Isogrid Structure vs. Honeycomb Sandwich Panels Structure as the Main Structure of LAPAN-A4 Satellite using Finite Element Method

LAPAN-A4 is the Indonesian fourth's microsatellite. LAPAN-A4 is planned to be launched as an auxiliary payload on PSLV, so the satellite has a maximum mass of 150 kg. Since the total mass of the LAPAN-A4 components to be loaded into the satellite is ±123 kg, the main structure can only weigh 27 kg. As a result of the mass restriction, solid 7-series aluminum plates as a structure are no longer feasible. The main structure's mass problem can be solved by using isogrid aluminum plates or honeycomb sandwich panels. LAPAN has never had experience using either of those types of structures as the main structure, so it is necessary to conduct a study before determining the choice of this main structural material. This paper will present the comparison results of the two structural solutions above by simulating the LAPAN-A4 main structure models to measure the value of each natural frequency using the finite element method. The first natural frequencies on the X, Y, and Z-axes of the isogrid structure are 102, 65, and 104 Hz, respectively, while the results for the honeycomb sandwich panels structure are 103, 85, and 139 Hz. Both simulations have met the requirements, but the natural frequencies of the isogrid structure on the Y-axis and Z-axis are still too close to the minimum natural frequency required, while the honeycomb sandwich panels structure has a greater range of the minimum requirement. Therefore, using honeycomb sandwich panels as the main structure for the LAPAN-A4 will make it much safer.