Verification of Rapid Thermal Design Approach using Design and Flight Data of Hodoyoshi-1 Microsatellite

A rapid approach for the thermal design of micro- and nano-satellites has been proposed for completing the thermal design of micro- and nano-satellites within about one year. In this approach, first, two simple concepts of thermal design are applied for a micro- or nano-sattelite. One concept is to decrease the temperature change of the whole micro- and nano-satellite by using the whole thermal capacity of the micro- and nano-satellite. The other concept is to decrease the temperature change of the inner structure on which components with a narrow allowable temperature range are mounted and which is insulated conductively from the outer structure. These two simple concepts lead to simple analysis method with small number of nodes. Second, the simple analysis method narrows the range of optical properties to keep the temperature within the allowable temperature range. Finally, the multi-node analyses are carried out for components out of the allowable temperature range using the optical properties obtained from analyses with the small number of nodes, in order to tune thermal conductance between the components and panels, and optical properties of the components. The thermal design approach was applied to Hodoyoshi-1 microsatellite. Hodoyoshi-1 microsatellite is about 50 cm wide, 50 cm long and 50 cm high, has a mass of about 50 kg, two inner plates, and solar cells on the body, flies on the Sun-synchronous orbit at the altitude of 500 km, and is pointing to the Earth. Verification of the thermal design approach has been carried out using the design data and flight data of Hodoyoshi-1 microsatellite. The temperature of Hodoyoshi-1 on orbit is within the allowable temperature range and is well accorded with the design data. It is clarified from this result that the proposed rapid thermal design approach is valid for the design of micro- and nano-satellite.