Enhancement of the vibration stability of a microdiffraction goniometer

Abstract

High-precision instrumentation, such as that for x-ray diffraction, electron microscopy, scanning probe microscopy, and other optical micropositioning systems, requires the stability that comes from vibration-isolated support structures. Structure-born vibrations impede the acquisition of accurate experimental data through such highprecision instruments. At the Advanced Photon Source, a multiaxis goniometer is installed in the 2-ID-D station for synchrotron microdiffraction investigations. However, ground vibration can excite the kinematic movements of the goniometer linkages, resulting in critically contaminated experimental data. In this paper, the vibration behavior of the goniometer has been considered. Experimental vibration measurements were conducted to define the present vibration levels and determine the threshold sensitivity of the equipment. In addition, experimental modal tests were conducted and used to guide an analytical finite element analysis. Both results were used for finding the best way to reduce the vibration levels and to develop a vibration damping / isolation structure for the 2-ID-D goniometer. The device that was designed and tested could be used to reduce local vibration levels for the vibration isolation of similar high-precision instruments.

Optimal dynamic performance for high-precision actuators/stages

“…It can be divided into three basic areas: ground motion studies 1,2 , existing equipment analysis and remediation [3][4][5][6][7][8][9] , and new design consideration 6,7 . The current work investigates a recently implemented robotic x-ray sample handling system with the intent of developing modeling techniques to aid future designs.…”