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MPB has developed advanced technologies based on smart radiator devices with thin-film tiles (SRDs) employing V1-x-yMxNyOn, for the passive dynamic thermal control of space structures and payloads. M and N dopants tailor the transition temperature characteristics of the tuneable IR emittance. The SRD has successfully passed major ground tests and validated its performance for extended use in the harsh space environment, with a target of up to 15 years GEO, in preparation for a flight demonstration of the technology [1]. This paper describes the optimization and validation of the SRD as an efficient thermal control system with tuneable thermo-optical properties for a microsat mission. The optimization involves tailoring the transition temperature characteristics of the tuneable IR emittance to near room temperature by using Tungsten-doped Vanadium targets for the deposition of V1-xWxOn.

MPB has developed advanced smart radiator devices (SRDs) for passive, dynamic thermal control of space structures and payloads. The SRDs employ a nano-engineered, integrated thin-film structure based on V1-x-yMxNyOn. Dopants, M and N, tailor the transition temperature characteristics of the tuneable IR emittance. This paper describes the progress in MPB's smart thermal radiator towards its validation as an efficient thermal control device for space environment. A set of environmental tests were performed in order to validate the coating resistance and performance stability in space. The tests included random vibration, thermal shock, and accelerated aging. In addition, the thermo-optic characteristics after exposure to Atomic Oxygen (AO) in a simulated LEO environment were similar to the “as deposited” characteristics. Preliminary radiation tests, comparable to 3 years in a GEO environment, indicate very low change in emissivity and solar absorptance relative to the initial values.

This paper describes recent advances in MPB's approach to spacecraft thermal control based on a passive thin-film smart radiator tile (SRT) that employs a variable heat-transfer/emitter structure. This can be applied to Al thermal radiators as a direct replacement for the existing OSR (optical second-reflector) radiator tiles with a net added mass under 100 gm/m2. The SRT employs a smart, integrated thin-film structure based on the nano-engineering of V1-x-yMxNyOn that facilitates thermal control by dynamically modifying the net infrared emittance passively in response to the temperature of the space structure. Dopants, M and N, are employed to tailor the transition temperature characteristics of the tuneable IR emittance. This facilitates thermal emissivities below 0.3 to dark space at lower temperatures that enhance the self-heating of the spacecraft to reduce heater requirements.