Vibration of a Flexible Solar Array Caused by the Change of Thermal Input in Orbit

Behaviour of large flexible space structures (antennas, solar arrays, frames of space stations, etc.) is strongly influenced by thermal loads in orbit. Thermally induced forces can affect flexible space structures in several ways: thermal buckling and thermally induced vibrations due to relatively rapid heating are two typical phenomena. In orbit attitude disturbances of an actual spacecraft are presented as a remarkable example of such phenomena. Analytical models are developed and numerical simulations performed in order to demonstrate that the vibration of the spacecraft flexible solar arrays is the most likely disturbance source. The results are shown to be in agreement with flight data and laboratory tests.