Evaluating the capability of laser scanning to measure an automotive artefact : a comparison study of touch trigger probe and laser-scanning

Abstract: In the automotive industry dimensional quality control is an important part of the production process, often carried out using coordinate measuring machines (CMMs). However, CMMs used in conjunction with touch probes have a relatively low measurement speed. There is also a close link between the cost of measurement and the number of discrete points captured, leading to a trade-off between the number of points that can be measured and the measurement time. Laser scanners offer a faster alternative to touch probe measurement, but have certain limitations. A number of studies have considered the accuracy of laser scanning using small artefacts; however, little work has been done on the verification of on-CMM laser scanning systems for large volume, industry-relevant measurement applications. In this research, a nominal representation of a vehicle body was used and 104 standard features were measured. The results show that the laser scanning sensor and CMM used in this study would, for the majority of measurements, provide a level of accuracy and repeatability better than which is typically required by automotive manufacturers for body shell quality inspection applications