NSRRC Activity Report 2023

Facility Development and Status 099 Fig. 2 : Mechanism design of the automation system. [Reproduced from Ref. 1] the platform (X-direction) to allow the radiation path to pass through the sample stage. The photon energy is subsequently measured by LYTLE or SDD detectors, and the It chamber, standard sample stage, and Ir chamber are used to calibrate the light source parameters during the experiment. When users intend to perform powder XRD experiments, they can move the platform to position the powder XRD experimental devices on the beam axis. Then, the MARIP equipment can be moved upstream (Y-direction), allowing users to conduct powder diffraction experiments. The final XRD experiment shares the same optical path as the powder XRD experiment, only differing in the measurement equipment. However, it is necessary to move the MARIP equipment downstream in the Y direction to prevent collisions during the operation of the XRD measurement equipment. The diagram below ( Fig. 2 ) depicts an illustration of the mechanical design architecture of the automation system. The movable adjustment platform (X1 motor stage) in the automation equipment is driven by a five-phase stepper motor and positioned on an optical scale. This component is primarily used for switching between XAS and XRD experimental setups. In XRD experiments, to minimize light loss, a vacuum tube needs to be installed in the XRD optical path, bringing the XRD collimator as close as possible to the experimental sample. However, during the switch between XRD and XAS, the collimator may interfere with the XRD measurement equipment. Therefore, a compressible vacuum bellows tube is used instead of a vacuum tube, and the XRD experimental components are mounted on the Y1 motor stage. Moreover, when switching between XRD and XAS systems, the XRD components need to be moved upstream first to avoid interference. The Y2 moto stage is used to switch between the MARIP detector and the XRD equipment during the powder XRD experiments. For uniform measurement of the sample structures, the R4 electric spin sample stage in Fig. 2 is employed, enabling the setting of the spin sample speed. The R3 electric rotary sample stage can accommodate 20 sets of samples and enables the switching of required measurement samples using a rotating disk mechanism. For XAS users, the Z1 motor stage can be used to select either LYTLE or SDD detectors. The R2 electric rotary disk can accommodate up to 20 sets of XAS samples, and the R1 rotary stage allows users to adjust the XAS sample and the incident angle of the light source according to experimental needs. Figure 3 shows the structure of the automated electrical control system in TLS 07A1 . 1 The crucial aspect of this electromechanical control system is controlling the positions of the mechanical components. In the XAS, powder XRD, and XRD systems of the TLS 07A1 , all movements of the automated platforms and sample stages are driven by stepper motors as the actuators for the mechanical components. Based on the specific requirements of each platform, optical scales or motor encoders are used to read the positions or angles of these mechanical components. The TLS 07A1 utilizes motion controllers from Galil to control the motors, and the positioning signals from optical scales or motor encoders are decoded by motion controllers and fed back to the control system (EPICS server), achieving precise position control of the motorized platforms.