Sponsored Post: A New way to Capture a Crash [w/video]

Car safety testing is a fast, dynamic process. The ability to capture the event accurately and completely requires two synchronized high-speed cameras that can capture the high-speed image flawlessly for analysis and evaluation and it must be done in three dimensions.

The ability to synchronize two high-speed cameras in such a violent event is not trivial and requires state-of-the-art high-speed cameras capable of providing 1000 frames per second at a high-resolution rate of 1500 by 1000 pixels. That is just the beginning of setting up a difficult test sequence. The more difficult feat to achieve is that synchronization cannot be off by more than 50 microseconds, a specification not achievable by many commercial systems. As a result, in order to properly capture the crash or test event, one must resort to paying out a significant amount of money to accomplish the high-speed multi-image event.

Example of a usual two-camera setup.

There has been an alternative high speed camera developed that employs the use of optical beam splitters to accomplish the two camera effect using just one high speed imaging camera. In concert with the car industry, a high-speed camera using a beam splitter created by a prism and two mirrors forms a virtual camera setup. It comes with a downside though as the horizontal resolution is reduced by 50%. The upside is that you save yourself a bucket of money. There are workarounds to offset the loss of horizontal resolution using more accurate calibration procedures with the use of non-planar mirrors. These mirrors have to be modeled to exact measurement and customized to the event being captured but the cost is far less than buying and synchronizing the second camera. The computer model of the test event generates all the calibration values and procedures.

Thus, we have successfully recorded and measured the dynamic surface deformations as applied to car safety testing through the capture of image sequences using either a one or two  camera setup.