With the Flex-3A, Otto Vision Technology offers a high-end optical 3D scanner for non-contact shape and coordinate measurement in automated quality control. Thanks to the further development of the image processing system and the integration of two 12 megapixel cameras from Baumer used as stereo cameras, one device is now sufficient for capturing high-precision 3D data for checking dimensions, shape and position in measuring fields from 20 mm to 200 mm.

The non-contact 3D measurement and geometry inspection of complex objects can be carried out in all production phases - from initial commissioning through the optimization and sampling phase to series production - in order to quickly identify deviations, detect sources of error and initiate corrective measures. The Flex-3A obtains 3D surface data in high point density for a full-surface target/actual comparison. Many manufacturers use the system from Jena, particularly in the stamping industry. "Other industries are also growing. Above all, we see a wide range of new applications in the plastics industry," says Gunter Otto, Managing Director of Otto Vision.

Two 12 MP cameras from Baumer's CX series used as stereo cameras provide the images for generating the 3D images. A rotatable reversible mount allows a complete 3D scan of the top and bottom sides. © Otto Vision Technology

With this further development, the company has streamlined its portfolio and can now realize measuring field ranges from 20 to 200 mm with just one device. The solution for the optical system was particularly challenging. Even with fixed measuring distances, as with the previous devices, the different measuring fields could only be achieved by changing the lenses.

Goodbye passport stamps

The Flex-3A works as a fully automatic multi-view system based on phase-measuring fringe projection with triangulation and phasogrammetry. The 3D measuring head is equipped with two 12 megapixel USB 3.0 cameras and an LED fringe projector with a resolution of 1440 x 1080 pixels. A third camera ensures multi-image registration. The parts to be inspected can be illuminated and recorded from several directions depending on their complexity. A complete 3D scan is achieved using an additional motorized turning fixture.

Flexible target/actual comparison

The recording method with three cameras from different angles is patented. "In addition to the two cameras on the 3D measuring head, we also use an object-fixed reference camera to determine the position of the test object. This allows the partial views to be photogrammetrically merged into a global 3D model with high precision - without having to glue registration marks, which saves additional time and costs," explains Otto. With the optional addition of a motorized turning fixture, the top and bottom sides can also be measured fully automatically. Thanks to its flexible design, the system is suitable for the initial sampling of prototypes, for spot checks during production as well as for incoming goods inspections of manufactured parts.

The recording of all image data and its compilation into an overall model, including calculation and evaluation, is automated and realized using powerful software. The digitized data can be aligned as point clouds or as a meshed STL surface to the coordinate system of the reference model. The graphical target/actual comparison, for example between produced parts and the corresponding CAD model, can be carried out quickly and easily in order to easily localize shape deviations such as warpage, shrinkage, offset or even tool wear.