Laser scanning reduces CMM time

The automotive industry is a huge business in Abu Dhabi. In 2010, the country revealed its plans to launch an automotive industry zone that will include everything from building vehicles to services and sales in Musaffah.

Customers in the automotive industry require technologies that will speed-up their inspection process. The 3D laser line scanning and point cloud processing drive a digital inspection process that drastically improves CMM productivity, while accelerating design-through-manufacturing by providing full geometry feedback.

3D scanning cuts CMM time

At car manufacturers, cross scanners automate the inspection of so-called "Christmas tree" features. Robots weld these complex metal features on sheet metal body parts to allow trim to be easily and securely connected by means of screws. By roughly 5 seconds, a cross scanner digitises the complete geometry of a single Christmas tree feature in order to determine its actual welding position. Scanning avoids spending hours manually mounting cylindrical extensions on the Christmas trees required for tactile measurement and removing them afterwards. With laser scanning, the entire CMM inspection process is executed more than 10 times faster.

High standoff distance and field-of-view depth enable cross scanners to realise major time savings when inspecting automotive casted parts. To take a full 3D scan of one side of an engine block, cylinder head or gearbox cover, the CMM only needs to move the scanner along parallel motion paths without indexing the head. With such limited CMM overhead, the scanner captures the complete surface, including full 3D characteristics of ribs, holes, flanges and pockets, at record speed. One hour is sufficient to set up and execute inspection, whereas detailed tactile inspection easily lasts more than a day.

Increased productivity

Saudi Arabia unveiled its first locally-built car in 2010, an all-terrain vehicle, called "Ghazal 1," and plans to manufacture 20,000 units a year. With 3D scanning a detailed 3D data requiring minimum preparation and measurement time can be provided. It can offer insightful information much sooner in every stage of the design-through-manufacturing process. This results in fewer iterations and shorter cycle times. Laser scanning responds to vehicle designers requesting that their manually tuned prototypes are converted into CAD overnight. A few hours are sufficient for a dual-horizontal-arm CMM equipped with laser scanners to generate a digital model of the full car.

Setting-up a plastic injection moulding machine to start producing plastic trim components is a complex and tedious process that requires multiple iterations. Graphic part-to-CAD comparison charts obtained by digitising first prototype samples instantly reveal how process settings can be optimised best in order to reduce the number of costly iterations. Also, when starting up new assembly lines, laser scanning enables car manufacturers to save time and cost. They virtually assemble digitised sheet metal body parts in order to identify potential part fitting issues, before bringing together the physically parts from multiple remote fabrication plants. Besides eliminating expensive checking fixtures, they succeed in reducing time-to-market for new car models, increasing competitive edge in the fiercely competitive automotive industry.

As a conclusion, laser scanning not only brings increased productivity to the CMM lab; it also enables the metrology department to contribute to the success of the entire design-through-manufacturing process. Laser scanners can be retrofitted easily on any existing CMM installation, requiring limited capital while the return of the investment can be extremely significant.