Multidisciplinary Senior Design Project

Flight Ready Heat Switch for Deep Cryogenic Use

Side-by-side photos of RIT students and activities with the text See How RIT is Advancing the Exceptional underneath.

Our customer: Dr. Zemcov is interested in launching spectrometers into space on sounding rockets. In order to get the best possible readings from these sensors they must be cooled to incredibly low temperatures to reduce noise and any internal heat emitted from the sensor. In order to keep these devices cool, an adiabatic demagnetization refrigerator (ADR) is used. Our team was tasked with building the heat switch component of the ADR. The ADR and heat switch must cool the detector and then mechanically disconnect before flight. A prototype was previously designed and nearly ready for testing but was not completed due to COVID-19 shutting down the cryogenics lab. The prototype designed by the previous P20129 team did not work at room temperature, but offered design changes from the first team (P19129) that would be carried over to this year's design. The prototype utilizes a rotary solenoid, a ratchet, and a peanut cam to open and close the arms which would clamp and unclamp to the sensory package. This year's design features a newly designed camshaft plate to reduce lateral movement of the ratchet mechanism, new springs, and bronze components instead of aluminum. Together these modifications have made the heat switch tremendously reliable at room temperature, in a vacuum, and up to 77K in the cryostat. The heat switch has also survived the required NASA vehicle level 2 vibrations as well as random vibration testing. Work continues on making this heat switch flight ready with manuals and "plug and play" electronics. Visitors can expect to learn more about cryogenics, flight ready systems, and about adiabatic demagnetization refrigerators.

Pouring liquid nitrogen into the cryostat for testing

Prototype assembled for testing, sitting on the gold plate of the opened cryostat

Prototype assembled for testing, sitting on the gold plate of the opened cryostat

Pouring liquid nitrogen from the tank into the bucket used to then pour into the cryostat

Pouring liquid nitrogen from the tank into the bucket used to then pour into the cryostat

Closed cryostat filled with liquid nitrogen

Closed cryostat filled with liquid nitrogen

P21129 Prototype Heat Switch

P21129 Prototype Heat Switch

NASA Level 2 Vibration Testing

NASA Level 2 Vibration Testing

Random Vibration Testing

Random Vibration Testing

Heat Transfer Testing Set Up

Heat Transfer Testing Set Up

Applying the Dry Lubricant to the Ratchet Teeth

Applying the Dry Lubricant to the Ratchet Teeth

Team Members
Chris Alexander,Chris Witmer,Cameron Collins,Matt Chuttey,Maxwell Williams,Matt Blanc

Project Website