By analyzing high-resolution digital photos, GM ensures that its automobile tooling equipment is operating correctly. The tooling equipment positions automobile components together during the manufacturing process, so it's critically important that all the pieces are in exactly the right place.
SMI Intl., an automotive engineering firm, introduced the FotoG close-range photogrammetry system from Vexcel as an alternative to traditional surveying techniques. FotoG can provide detailed noncontact measurements of objects without having to shut down a work area. Using the system involves taking digital photographs of the objects and then using software to identify photo relationships and perform image processing. Once these steps are done, the system lets you extract 3D coordinates, distances, and objects from the digital images.
After a year of results from pilot programs at GM plants around North America, the GM certification committee approved the system for GM's use. During pilot studies, SMI found that measurements averaged 59 min. from site setup to final results, and typical accuracies were ±0.02 mm to ±0.004 mm on a 3 m object. The system is also immune to vibrations, a definite plus for this application.