Control system for the 2nd generation Berkeley automounters (BAM2) at GM/CA-CAT macromolecular crystallography beamlines

GM/CA-CAT at Sector 23 of the Advanced Photon Source CAPS) is an NIH funded facility for crystallographic structure determination of biological macromolecules by X-ray diffraction. A second-generation Berkeley automounter is being integrated into the beamline control system at the 23BM experimental station. This new device replaces the previous all-pneumatic gripper motions with a combination of pneumatics and XYZ motorized linear stages. The latter adds a higher degree of flexibility to the robot including auto-alignment capability, accommodation of a larger capacity sample Dewar of arbitrary shape, and support for advanced operations such as crystal washing, while preserving the overall simplicity and efficiency of the Berkeley automounter design. Published by Elsevier B.V.