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Next time you have it in mind to strap a camera on a tiger shark, you might consider first getting in touch with the National Geographic Society. Engineers at NatGeo’s Remote Imaging Laboratory have, over the years, perfected their now-famous
Crittercam for just such a purpose.
The most recent version of the Crittercam is for undersea use. It employs an SLS (selective laser-sintered) part to both brace and center a controller board and to serve as a support for mounting the video camera.
CNC machining was the only real alternative to making the component with SLS, says NatGeo Mechanical Engineer Graham Wilhelm. But holes for centering the camera come into the bracket at angles that would have necessitated a five-axis CNC operation. “We just didn’t want to get into that,” he says.
NatGeo instead uploaded their part design to the Web site of manufacturing services company
Quickparts.com Inc. in Atlanta. Quickparts makes the SLS parts, which were ready in a few days, with a laser that sinters powder-based materials together, layer by layer, to form a solid model.
National Geographic introduced the first generation of the Crittercam in 1987 and has continually improved it. The Crittercam has been used in March of the Penguins and in National Geographic’s Wild Chronicles, among other things.
The undersea Crittercam containing the SLS part is about 10-in. long and weighs under 2 lb. The SLS bracket holds a 16-bit controller as well as the camera mount. The device has enough battery capacity to record for about 8 hr and can withstand depths to about 1 km. Its back end contains environmental sensors that, besides a depth sensor, include a compass, accelerometers, and a velocity and temperature sensor.