Evaluation of the Metrological Performance of a Handheld 3D Laser Scanner Using a Pseudo-3D Ball-Lattice Artifact.

This paper proposes the use of a pseudo-3D ball-lattice artifact to characterize a handheld laser scanner from a metrological standpoint. The artifact allows the computation of local and global errors in measurement by using the reference-frame-independent parameters of size, form, and distance within the measuring volume of the scanner, and in a single point cloud, without the need for registration. A set of tests was performed using the whole measuring volume, and three acquisition parameters, namely the orientation of the sweeps during the scans, the exposure time, and the distance to the scanner were analyzed for their effects on the accuracy of the scan data. A composite error including the errors in measuring size, form, and distance was used as a single figure of merit to characterize the performance of the scanner in relation to the data-acquisition parameters. The orientation of sweeps did not have a considerable effect on the errors. The accuracy of the scan data was strongly affected by exposure time and its interaction with the distance at which the artifact was scanned. The errors followed a quadratic trend with respect to the distance of the artifact to the scanner. The tested scanner performed best at its manufacturer's recommended stand-off distance.

A low-cost open-source automated shot peen forming system.

The aerospace industry relies on shot peen forming to form sheet metal parts and correct distortion in machined parts. The shot peen forming community is developing simulation and planning methods to meet the industrial need for automation. Researchers need to invest in expensive industrial robots contained in large blasting cabinets to perform the experimental validations of their proposed methods. To bypass this need for expensive industrial-grade equipment, this work presents a low-cost shot peen forming system that enables researchers to validate their methods experimentally on small samples. Conventional installations can cost a few 100,000 USD while the proposed prototype only costs 400 USD to produce. Such a prototype can operate on a tabletop with conventional electrical installations. The use of small samples for validation further reduces the cost of experiments and allows for faster development.