A major booster test for NASA’s Space Launch System in June doubled as a demonstration of a new high dynamic range video recorder that captured unprecedented imagery of the rocket firing, revealing hidden details normally masked by the motor’s bright-hot exhaust.
Developed by engineers at NASA’s Stennis Space Center in Mississippi, the high-tech camera is able to record multiple slow motion exposures at once. Conventional cameras can only record in one exposure, and that is a problem when trying to document very bright events like a rocket test.
The High Dynamic Range Stereo X, or HiDyRS-X, camera attempts to fix the problem. Imagery from the new recording system perfectly exposes everything within its field-of-view, showing the rocket motor’s supersonic exhaust plume while still keeping other parts of the image visible.
A typical camera with one exposure setting to capture the bright exhaust plume would be unable to see what is happening in nearby, darker areas. If the camera was set to resolve the booster itself, the brilliant exhaust would overwhelm the camera sensor, over-exposing the image.
Howard Conyers, the NASA engineer picked to lead the HiDyRS-X project, set up the camera near a solid rocket booster designed for the Space Launch System to capture video of a June 28 qualification firing in Utah. The 154-foot-long (47-meter) booster generates more than 3 million pounds of thrust, and two of them will provide about three-quarters of the power needed to send the huge rocket skyward.
The June 28 test conducted by Orbital ATK, the booster’s builder, was the first time the high dynamic range camera was used in a full-scale environment, NASA said. The camera previously recorded smaller rocket plumes during tests at Stennis.
The slow motion video released by NASA shows the booster’s nozzle gimbaling, or swiveling, to mimic its movement during a real launch. The gimbal system will help steer the Space Launch System in flight.
“I was able to clearly see the exhaust plume, nozzle and the nozzle fabric go through its gimbaling patterns, which is an expected condition, but usually unobservable in slow motion or normal playback rates,” Conyers said in a NASA statement.
The SLS solid rocket boosters are extended versions of the motors flown on the space shuttle. The rocket boosters burn a mixture of powdered aluminum fuel and ammonium perchlorate oxidizer, and temperatures inside the motors reach nearly 6,000 degrees Fahrenheit, or 3,300 degrees Celsius, during the two-minute burn.
NASA engineers partnered with Innovative Imaging and Research Corp. to develop the high dynamic range video system.
The SLS test firing in June marked the second and final qualification test for the heavy-lift launcher’s solid rocket boosters. The first SLS mission is scheduled to launch in late 2018 from NASA’s Kennedy Space Center in Florida on an uncrewed test with the Orion spacecraft, a next-generation spaceship NASA is developing to carry astronauts into deep space.
Another SLS/Orion launch with astronauts will take off in the early 2020s on a flight around the moon.
Email the author.
Follow Stephen Clark on Twitter: @StephenClark1.