NASA researchers at the White Sands Test Facility (WSTF) Remote Hypervelocity Test Laboratory (RHTL) (Las Cruces, NM, USA) are using two SIMX8 ultra high speed framing cameras from Specialised Imaging to capture and analyse framing sequences of hypervelocity micro-particle impacts. These impacts simulate micro-projectiles that could cause problems in satellites and vehicles used in space.
Specialised Imaging's Sureshot triggering system has improved the timing accuracy of the researcher's hypervelocity impact experiments to nearly 100 per cent. With the cameras, the NASA researchers are able to capture different sequences of framing data enabling the velocity, shape, size, orientation and integrity of the fast travelling micro-projectile to be calculated.
For many years, researchers used film cameras running at fixed framing speeds to record the impacts. While film cameras are able to cope with deviations from the expected velocity of micro-projectiles, they are typically large, require considerable manpower to run, have limited framing speeds or exposure times, and require special optical systems and dedicated laser illumination systems to operate.
A new generation of multi-frame intensified CCD cameras that operate faster, are easier to use and offer shorter exposure times are now the tool of choice for recording hypervelocity events. However with fewer frames to record the hypervelocity event it is critical that the timing of the arrival of the micro-projectile is extremely accurate such that the frame sequence coincides with the arrival of the projectile prior to the impact.
The Sureshot triggering technique allows the camera to deliver ultra high spatial resolution imaging of framing sequences of micro-projectiles travelling in excess of 8km per second.
The optical design of the SIMX provides a choice of up to 16 separate optical channels without compromising performance or image quality. Effects such as parallax and shading are eliminated and the high spatial resolution (>50 lp/mm) is the same from frame to frame and in both axes. Individual ultra-high resolution intensified CCD detectors, controlled by state-of-the-art electronics, offer almost infinite control over gain and exposure allowing researchers total freedom to capture images of even the most difficult transient phenomena.
