Carbon
Carbon NASA thrusters
Final vehicle layout with instrumentation packaging (left); the CE 221 thruster design that is packaged between the instrumentation (middle); and metal face (right).
Carbon’s additive manufacturing technology has enabled the production of four high-performance thrusters for a NASA free flyer technology demonstration project.
Seeker is a robotic free flyer inspector that was launched aboard the Cygnus spacecraft for Northrop Grumman’s 11th contracted Commercial Resupply Services mission to the International Space Station earlier this month. With just over a year to launch Seeker from the start of the project, NASA accessed Carbon’s Digital Light Synthesis (DLS) 3D printing technology via The Technology House (TTH), a production partner of the Californian OEM’s.
The additively manufactured thrusters were newly designed for Seeker’s cold-gas propulsion system, ensuring a number of critical components, from four cold gas jets and gas tubings to bracketing and sensors, could be integrated in close proximity on the same face of the vehicle. Also on this face is an Inertial Measurement Unit (IMU), laser rangefinder (LRF), four sun sensors, two cameras, and a communication antenna.
Carbon
Carbon NASA thrusters
Seeker (left) is an external, free flying robot that will inspect Cygnus. Kenobi (right) is the translator between Cygnus and Seeker, storing all of Seeker’s valuable data. Each vehicle is approximately 10 cm x 10 cm x 30 cm in length.
TTH and NASA used Carbon’s Cyanate Ester (CE 221) material, which boasts long-term thermal stability, strength, and stiffness, to run through ten design iterations of the thruster. The CE 221 grade successfully underwent NASA’s extensive development and qualification testing phase, which included rupture tests at high pressures. In doing so, the service provider noticed some variability in the 100+ articles tested and had to work with NASA to add some design elements to enhance the accuracy and printability while not compromising the functionality of the thrusters.
Once that was done, the printed parts were validated for flight use and those thrusters have now been launched within the assembly of the Seeker’s cold-gas propulsion system, helping it to keep a watchful eye over the Cygnus cargo spacecraft.
“Other plastics used in additive manufacturing wouldn’t be able to hold up to everything you’re going to get through this whole process. It has to hold up to being pressurised, to the cold of space, to the heat from the sun,” commented Greg Cebular, Vice President of Sales at TTH. “Really, it was the high-temperature Carbon CE 221 material that drove this. It was the whole reason that NASA was able to produce this on an additive technology.”
NASA completed the project in just over a year and at a cost of $3m.
