Laser Scanning Keeps Old Military Equipment in Service

Military hardware is aging fast. In some cases, it's older than the soldiers who use it. Spare parts are required to keep this equipment running, but many of the companies that supplied them have long left the business, and drawings and documentation may no longer exist. Reverse-engineering firms have stepped in to re-create the parts using the latest computerized numerical control machinery, and laser scanning systems offer them performance benefits.
Reverse-engineering firm Radian Milparts of Eastlake, Ohio, turned to laser scanning. Using the ModelMaker laser scanner from system integrator Nvision Inc. of Southlake, Texas, along with a coordinate measuring machine, an operator at Radian Milparts can switch from scanning contours to capturing individual points with the push of a button.
Laser scanning systems work by projecting a line of laser light onto a surface to be measured while a camera continuously triangulates the changing distance and profile of the line as it sweeps over the object. A computer translates the video image of the line into 3-D coordinates, providing real-time data renderings that offer the operator immediate feedback on areas that might have been missed.

In the reverse-engineering application, a technician moves the scanner around the object in a manner similar to spray painting. The data is sent to software to convert the point cloud into a surface model that can be imported into computer-aided design software.
ModelMaker's head, which is manufactured by 3D Scanners Ltd. in London, incorporates an eye-safe laser that produces a red stripe of light, similar to that used in supermarket scanners. The camera measures 760 points in a line at 30 stripes per second, resulting in a measuring rate of approximately 23,000 points per second.

Laser Scanning Keeps Old Military Equipment in Service - September, 2005