History and Experience
The HVIT was founded in 1980 with a mandate to study the hypervelocity impact (HVI) characteristics of composite materials such as graphite epoxy. A small, 1.7 mm bore, light-gas gun was built in-house from drawings supplied by the NASA Langley Research Center. A few years later, a 4.3 mm bore light-gas gun was purchased from a commercial vendor. It was then modified and improved to perform meteoroid and orbital debris shielding research. Later, the HVIT added a 12.7 mm bore gun, which was provided by the NASA Ames Research Center Hypervelocity Free-Flight Facility.
Since its inception, the HVIT has performed and analyzed over 8000 hypervelocity impact experiments on spacecraft shields and materials. These experiments and the ensuing analysis, in combinations with countless hydrocode simulations, have contributed to the development of shield ballistic limit equations used as the foundation for thousands of meteoroid and orbital debris threat assessments in support of critical space programs.
The HVIT has a very experienced and well trained staff. Their diverse and complementary skills, across many engineering disciplines, allow for the lab to design and implement complex turn-key shielding solutions. The HVIT has many scientists, engineers, and technicians who are experts in the areas of materials science, hypervelocity impact physics, penetration mechanics, computer engineering, probability analysis, structural mechanics, laser intervalometry, optics, quality control, and safety.
The HVIT has a lot of equipment and tools at its disposal which provide for a very wide testing and analysis capability.
The primary charter of the HVIT is to support space programs by researching and developing meteoroid and orbital debris impact protection systems for NASA and other commercial spacecraft. The HVIT supports this initiative by operating three light-gas gun ranges and associated diagnostics. The HVIT also provides state of the art post-test analysis capabilities.
The testing capability of the HVIT, provided by the 3 light-gas gun ranges, allow for 100 micron aluminum balls up to a 10 mm aluminum balls, to be launched at velocities ranging from below 2 km/s to over 7 km/s. The diagnostics for the HVI testing consist mostly of flash x-ray systems and ultra-high speed cameras. The ranges are also equipped with light flash photo-detectors and laser intervalometers, all of which allow for the projectile velocity to be determined.
The ranges use Cordin camera systems, which are capable of framing rates of up to 2.25 million frames per second using standard Kodak IR film cassettes. The camera is a rotating mirror system which exposes each frame of a static circular roll of film for a few microseconds. The mirror is driven by a turbine powered by compressed nitrogen or helium.
The .50 caliber range presently incorporates a 300 kV HP model 43733A and a 150 kV HP model 43731A flash x-ray system. The 300 kV head is used to obtain orthogonal soft x-rays of the target, projectile, and/or debris plume. The 150 kV head utilizes three stations to obtain sabot separation information, projectile integrity data, nd projectile velocity.
The analysis support provided by the HVIT performs several functions including:
post-impact analysis of experimental HVI test data produced with the HVIT ranges
numerical and analytical simulations to predict impact response beyond experimental test conditions (hydrocodes)
risk and damage assessments for spacecraft exposed to the meteoroid and orbital debris environments (notably Station, Shuttle, Mir, and EVA)