The demands of space simulation
Space simulation chambers are a primary test medium for spacecraft and subsystems. They must replicate the vacuum and thermal extremes of outer space. According to industry analysis, these chambers subject components to deep vacuum while cycling through temperature ranges from hundreds of degrees above to hundreds of degrees below zero. Systems are typically divided into two types: thermal vacuum chambers and those with an integrated solar simulator, known as solar simulation chambers.
Chamber operation and component requirements
Creating the required environment is a complex engineering task. One report on vacuum technology for space simulation notes that to achieve the tremendous pumping speed needed in the presence of gases like xenon, cold panels are added to the chamber. These panels are cooled to temperatures below 50 Kelvin by single-stage cryocoolers, causing gas to condense directly on them. A small cryo panel of 600mm in diameter can achieve a pumping speed of 16,000 liters per second inside the chamber. All components interfacing with this harsh internal environment, including any rotating shafts for motion simulation, must maintain a perfect hermetic seal.
Hermetic connections for power and motion
This is where specialized feedthroughs become necessary. Hermetic electrical feedthroughs allow for the connection of power and signal lines within the TVAC (Thermal Vacuum Chamber) environment. For applications requiring rotational motion inside the chamber, a rotary feedthrough that does not compromise the vacuum is required. A tri-axle magnetic fluid feedthrough provides this function, using a magnetically confined fluid to seal around rotating shafts. The technology permits multiple axes of rotation to pass into the vacuum space without leaks, which is essential for positioning samples, sensors, or components during testing.
Integration in real-world testing facilities
The practical use of these chambers is widespread in research. For instance, the Earth and Space Institute at UMBC operates a thermal vacuum chamber housed in the Physics Building, Room 333. Such facilities, filled with instrumentation and wiring, depend on reliable feedthroughs. The chamber dimensions for systems with solar simulators are themselves determined by the solar simulator's optical geometry and required motion simulation capabilities. Every penetration into the chamber wall is a potential failure point, making the selection of feedthroughs a significant engineering decision focused on long-term stability and zero leakage.
We provide hermetic sealing solutions for these challenging environments.