ALSA: Automatic Laue Sample Aligner

The co-alignment of multiple individual single crystals is a common practice in mass-sensitive techniques like μSR and inelastic neutron scattering, particularly when limited by the ability to grow larger crystals. This alignment process has historically been labor-intensive and often not very precise (e.g. [1]). The ALSA device aims to revolutionize this procedure by automating the co-alignment process through the integration of machine learning and cutting-edge technologies. Utilizing a state-of-the-art X-Ray Laue diffractometer, robotic manipulators, real-time camera recognition, and bespoke neural network software for crystal placing and Laue pattern solving, ALSA promises to be a game-changer in the field of sample preparation. Its implementation will significantly accelerate the sample preparation process, offering a substantial leap forward in efficiency and precision.

To glue small crystals as close to each other as possible, we have developed an online algorithm for irregular polygon stacking; a series of benchmarking tests proved, that it is the most efficient online algorithm available. In this presentation, we will focus on the hardware and software design of the device, as well as practical tests on inelastic neutron spectrometer IN12, where more then 200 irregular single crystals of Na₂BaMn(PO₄)₂ were automatically coaligned with mosaicity below 2 degrees.



[1] Duan, C. Et al. Nature 600, 636–640 (2021). doi:10.1038/s41586-021-04151-5

[2] Proposal 4-01-1795, ILL