Rotation and axial motion system IV (RAMS IV) load frame

In spring 2021, the fourth generation of Rotation and Axial Motion System (RAMS IV) load frame was commissioned with X-rays at the Structural Materials Beamline (SMB)


The main objectives of commissioning were to enable communication between the existing control system of the beamline (SPEC) and the new control system of RAMS IV (Aerotech), and to synchronize triggering of X-ray detectors with positions of the rotation stages on RAMS IV. To this end, a number of new scripts were written and tested for both SPEC and Aerotech for executing commands, exchanging experimental parameters, interlocking and “handshaking” between the two systems. During the last few days of commissioning, a series of X-ray measurements were performed on a sample mounted on RAMS IV to test the main functionalities of the new load frame.


The RAMS load frame series collectively form the gold standard for high-impact, precision in-situ X-ray mechanical testing at high-energy synchrotrons. The longstanding collaboration between Air Force Research Laboratory (AFRL) and Pulseray Inc. has delivered a new design and controls system.

Two RAMS IV frames were built: (1) a CHESS design for in-situ X-ray studies, and (2) an AFRL design for ex-situ studies. The AFRL machine can be used for ex-situ proof-of-concept, preparatory loading, or longer mechanical loading tests that can complement and inform work that is done in situ on the CHESS machine.

RAMS IV is optimized for simultaneous tension, torsion, and fatigue loading. Torsion and fatigue loadings are new features over the second generation of RAMS (RAMS II) that has been (and is still being) used with many user experiments at CHESS.

Read more on the CHESS website

Image: Staff Scientists Kelly Nygren and Peter Ko worked in tandem with AFRL to commission the RAMS IV