The WMG Product Evaluation Technologies Group, in collaboration with Nikon Metrology and Jaguar Land Rover, are investigating the optimisation of laser scanning technologies for production measurement systems in automotive applications.
Research objectives of an independent validation study by WMG:
Assessment of the Nikon Metrology laser triangulation sensor (Cross Scanner) and associated CMM programming software, on an artefact representative of an automotive body shell using a recognised measurement plan.
To develop and optimise a measurement strategy that will deliver the best possible quality of data, and that could be realistically replicated in a production environment.
Surface and edge point features have shown that it is possible to obtain a 99% repeatability of 20µm or better.
This potential has been demonstrated in circle features but further work is required to optimise measurement setting.
The agreement between the measured deviation reported by the laser scanner and the touch probe is consistently within 50µm for surface point and circle features. This represents 1.67% of the Body in White tolerance.
Impact of research:
The ability to take accurate and repeatable measurements of a product as quickly as possible is critical to any high volume, high value manufacturing process.
This research has been able to demonstrate that time savings of up to 70% of the overall measurement cycle time for body shell inspection are possible, although some of these savings must be sacrificed to improve repeatability. Furthermore, installing the described laser scanning system on to an existing twin column CMM will cost less than a fifth that of installing an additional CMM and results in no increase in the physical “footprint” of quality inspection facilities.