With budgets tight and production runs tighter, parts validation and quality measurement are even more critical than in previous years. Ensuring parts and assemblies as produced are matching their CAD data is an important requirement of non-contact systems these days, be it at the beginning or midway through parts' production.
While there are numerous non-contact applications measuring airliner-wing sized parts, the meaty portion of the validation market ranges from a bolt to a car door panel in size. Several inspection technologies have been upgraded for 2009 or are just now coming to the North American market; here are three new non-contact scanning tools, including laser, white light and computed tomography.
Metris (metris.com) opted to go digital with its XC65D multi-laser scanner. It discontinued the analog charge-coupled device CCD camera that it had been using and moved to a digital complimentary metal-oxide semiconductor CMOS Array camera to collect data. The result is a rule of three: 3-D scanning, using three lasers in a cross pattern to acquire a 3D measurement at three times the speed in collecting data than the system it replaces.
The new system includes a third-generation sensor, ESP3, to scan surfaces with varying colors and surfaces, including shiny surfaces, which are often difficult to measure with optical systems. The processor enables scanning under differing lighting situations, particularly for scanning parts in different manu-facturing stages, including bare sheet metal parts and finished products.
The accuracy for the XC65D is rated at 0.0006 in. The XC65D scanning speed in cross-scanner mode is 25,000 points per second and in-line scanner mode is 75,000 points per second. The tool is mounted to the Renishaw PH10M(Q) motorized indexing probe head with Multiwire.
White Light Comet5
Steinbichler Vision Systems (steinbichler-vision.com) makes a variety of laser and white light scanners. It's most recent model, the Comet5, is a medium-format, white-light fringe system that measures and validates quality on a variety of components. It is the fastest system the company offers.
It can detect features at the resolution of 25 microns or smaller. The system recently added an 11 megapixel camera with a 4008 x 2672 resolution, and a measuring time of 2 to 3 seconds to scan 800 mm square. The Comet5 also is available in 1.4-, 2.0- and 4.0-megapixel cameras. Its software allows the scanner to increase or decrease its exposure based on the ambient light source and to accommodate multiple surfaces, from shiny and finished to cast metal parts.
The system is designed for high-throughput scenarios, such as production quality control, as well as analyzing individual parts, from bolts to tools and dies, plastic injection parts, and clay models. The 3D digitizing system offers a photogrammetric measurement method with its integrated marker projection. As a result, the system can be configured for automated measurement procedures for large-scale objects, such as using a robot-controlled sensor.
ImTec's (imtec.com) ILUMA Sprite CT Scanner NDI1300 gets its name not only for its size—about the size of a small document copier—but by the size of things it analyzes. The computerized tomography (CT) scanner hones in on small parts at high (10 micron) voxel resolution up to larger (190 mm) parts at 100-micron resolution.
The four-stage system includes a high energy detector and a 90- or 130-kV microfocus X-ray scanner. With a 127-micron resolution detector, the system measures a 25 x 20-cm active area.
The machine is geared toward validating small and intricately manufactured components, such as electronics. The part is placed inside the machine. Scanning is performed in about a minute, then another 10 minutes are required to process and view, depending on the resolution sought. Very high-resolution scans, such as 200 microns on a 20 cm sample size, for instance, typically takes 20 minutes to scan and process.
With the massive upload of data, several gigabytes per part, the Sprite includes a 1-terabyte hard drive that can be replaced as needed. The system, ImTec says, requires little if any maintenance and can be powered from a standard wall outlet.