Space Test Program - Houston 3 - Variable emissivity radiator aerogel insulation blanket dual zone thermal control experiment suite for responsive space (STP-H3-VADER) investigation tests a variable emissivity radiator and a new form of multilayer insulation that uses Aerogel as the thermal isolator in order to protect the spacecraft from the harsh extremes of the space environment. The Aerogel material provides a more durable, lighter and cheaper alternative to traditional spacecraft thermal blankets. The use of this material could reduce the costs related to spaceflight by reducing the required spacecraft mass and increasing design efficiency.Principal Investigator(s)
United States Department of Defense Space Test Program, Johnson Space Center, Houston, TX, United States
Air Force Research Laboratory, Kirtland AFB, NM, United States
National Aeronautics and Space Administration (NASA)Sponsoring Organization
National Laboratory - Department of Defense (NL-DoD)ISS Expedition Duration:
March 2011 - October 2013
27/28,29/30,31/32,33/34,35/36Previous ISS Missions
This is the first mission for STP-H3-VADER.
The primary data collected by VADER is the temperature-time history of the variable emissivity devices (VEDs) and the reference samples during each test run. In addition, the research team tracks the number of switching cycles, the emittance state, and the power for the VEDs. From these, the emissivity of the samples will be calculated in both the low and high emittance states as well as estimate the lifetime performance of the materials. As for the aerogel blanket, the research team measures the temperature gradient between the outer and inner layers of the blanket to assess the performance of the blankets. These thermal gradients provide performance data of the aerogel blanket as an insulator allowing for a comparison to traditional MLI systems. There are eight resistance thermal devices (RTDs) integrated into the blanket by design and additional four mounted to the bracket to which the blanket attaches. Any performance degradation due to exposure to the space environment will be noted. The results for both of these technologies are to be used to design the final thermal control approach to transition to responsive space-class spacecraft.
The STP-H3-VADER investigation provides spacecraft performance information intended to reduce the design and development time and costs of related satellite components with regards to spacecraft thermal protection.Earth Applications
The spacecraft that these technologies apply to include those supporting earth-bound communications. The improvements that STP-H3- VADER intends to demonstrate creates more robust and capable satellites that are used to interface with ground systems.
Health, Status and Experiment Data are downlinked via standard ISS 1553 communications protocols. STP-H3 is comprised of a compliment of 4 individual investigations that shares a command window of 4 hours a day throughout the week. TReK is used for commanding and downlinking of data from the investigation hardware to the ground. There are 5 remote TReK Payload Operation Control Centers (POCC) that coordinate with the Payload Operations Integration Center (POIC) at MSFC via IVoDS.Operational Protocols
STP-H3 is an external investigation that does not require crew internal operations;therefore, direct communication is not required. The TReK operators communicate with the POIC, specifically the Payload Rack Officer (PRO), to be enabled for commanding. The PRO in-turn communicates with the Payload Operations Director (POD) for authorization to command.