Vibration tests of a cube corner reflector assembly of LARES2 satellite

In 2020 during the qualification flight of VEGA C launcher, the consolidated version of the VEGA launcher, the LARES 2 satellite will be put in orbit. LARES 2 will be the evolution of the ongoing LARES satellite. LARES 2 will be a laser tracked satellite completely passive especially designed for improving by an order of magnitude the results of LARES on the tests of the general relativity. The achievement of these goals will pass through several scientific and engineering challenges and mission constraints. Satellite altitude and procurement time have driven the selection of the Cube Corner Reflectors (CCRs) used for the mission, in fact the nominal orbit of the satellite will have a semimajor axis of about 12,270 Km, an eccentricity nearly zero and an inclination supplementary to the one of LAGEOS 1 (i_LAGEOS= 109.83°): due to this higher altitude with respect to LARES satellite orbit, the overall reflecting surface one would obtain using the same design of LARES would not assure the proper operation of the LARES 2. To increase the reflecting surface and the accuracy in the ranging measurement, CCRs with smaller diameter have been selected. The use of smaller CCRs has increased the number of the CCRs themselves, causing a significant increase in cost and above all in procurement time which is not compatible the mission schedule. For this reason the selection of COTS CCRs was the only viable solution. The selected CCR from a commercial producer had never been used in a space program, creating the need of designing a proper mounting system able to keep in a safe condition these fragile payload during the launch but, on the other side, do not affect the performances of the satellite. This paper presents the tests performed to qualify the specifically designed mounting system for the CCRs that will be used on LARES 2.