Effectiveness of low-cost thermal vacuum tests of a micro-satellite

This paper presents the experience gained at the Integration and Tests Laboratory—LIT, National Institute for Space Research—INPE, in São José dos Campos, SP, from the thermal vacuum tests campaign of the SATEC protoflight spacecraft, held from February 6th to 12th, 2003. The Satélite Tecnológico (SATEC) is a micro-satellite made in Brazil, as a payload for the Brazilian launching vehicle VLS-1.3, scheduled to be launched in the year of 2003.1 Considering the small size, relatively small cost and limited responsibility of this particular micro-satellite, the environmental tests should be performed in a short period of time requiring as low cost as possible, albeit being reliable, comprehensive and representative. For the thermal vacuum tests basically it was used a medium-size space simulation chamber, complemented by the use of the technique of thermal radiant heat plates for simulation of the heat input from the orbital thermal conditioning. This paper details the infrared testing technique applied to the acceptance tests of the Brazilian micro-satellite, including the adopted test setup, the thermal vacuum chamber mode-of-operation and performance, the precise thermal conditioning and controlling of the radiative heat plates, and the results obtained in terms of spacecraft temperatures.