Distributed control system using a remote distributed object model for 1.8-GeV synchrotron radiation beamlines at TSRF

A distributed control system has been developed to control synchrotron radiation beamlines for the 1.8-GeV storage ring at Tohoku Synchrotron Radiation Facility (TSRF), Tohoku University, which has 50 beamlines for soft X-ray optics/microscopy, lithography, and biomaterial research. The system is composed of outlying nodes and remote operator consoles connected to a network. Each beamline is controlled by its own outlying node independently of adjacent beamlines in accordance with physics experimental requirements. The control system protects ultra-high vacuum components of the beamline and the storage ring by closing valves/shutters upon detecting a vacuum failure. The system was implemented using a distributed object model, Java remote method invocation (RMI). The control system provides information on the operation of the beamlines to remote clients such as operator consoles over the network in order to operate the TSRF. The design and implementation of the distributed control system as well as the control scheme for the synchrotron radiation beamlines at TSRF are described in this paper.