A   B   C   D   E   F   G   H   I   K   L   M   O   P   R   S   T   U   V   W  

vacuum

Paper Title Other Keywords Page
WECOMA04 What's behind an Accelerator-Control-System? controls, monitoring, linac, synchrotron 13
 
  • R. Schmitz
    DESY, Hamburg
  There are a lot of features a control-system should have. Some of which are essential, e.g. that minimum set of application-programs and the infrastructure they need to run which at least allow operators to switch on and off the accelerator. Other features are not as obvious as GUIs, intelligent control algorithms or data-acquisition methods, but they require considerable manpower and should not be underestimated, for they have a major impact on the availability of the control system. This paper will describe the efforts made and being made by the control-systems group at DESY to provide a reliable tool for the operators, minimizing the downtime caused by control-system failures. This paper is a partial review of this aspect of computer based accelerator-control dating back to the late 1970s when the accelerator PETRA went into operation, controlled entirely by computers, i.e. mini-computers from NORSK DATA. Notwithstanding the respect we owe to the computer and to the technology which supports it, a good Control-System group behind an Accelerator-Control-System is essential to its success.  
slides icon Slides  
 
WECOAA02 The TINE Control System Protocol: How to Achieve High Scalability and Performance controls, background, monitoring, brilliance 19
 
  • P. Duval, S. W. Herb
    DESY, Hamburg
  Over the years TINE* has implemented numerous strategies for achieving high efficiency regarding data transport within a distributed control system. This was in fact essential in controlling a large machine such as HERA**. In modern times, a control system protocol suite must offer interfaces to many and sundry development platforms (not simply C++ and java) and it must support 'part-time' application developers, who might not be so well-versed in writing 'efficient' applications. This is an important point and easy to overlook until it is noticed that front end servers are struggling due to poor data flow models. For instance, a magnet server with 200 PSCs (Power Supply Controllers) might be accessed by a simple panel application which synchronously polls the readback values of all PSCs individually. The same server will have a much easier time if the client can be 'coerced' into acquiring the information asynchronously and as a multi-channel array of all values. TINE now offers various 'second-order' protocol features which go a long way in not just allowing but 'enforcing' efficient data transfer. We shall describe some of these features in this article.

* http://tine.desy.de
** Duval et al., “TINE: An Integrated Control System for HERA”, Proceedings, PCaPAC’99, 1999.

 
slides icon Slides  
 
WEPL004 Accurate Measurement of the Beam Energy in the CLS Storage Ring storage-ring, feedback, electron, energy-calibration 36
 
  • J. M. Vogt, J. C. Bergstrom, S. Hu
    CLS, Saskatoon, Saskatchewan
  Resonant spin depolarization was used at the Canadian Light Source (CLS) to measure the energy of the beam in the storage ring with high accuracy. This method has been employed successfully at several other synchrotrons in the past. At the Canadian Light Source, however, resonant spin depolarization is an intrinsic capability of the transverse feedback system, which is based on a Libera Bunch-by-Bunch unit. The Bunch-by-Bunch system used at the CLS was customized to include a bunch cleaning feature based on a frequency-modulated oscillator. By setting the frequency of this oscillator to the spin tune, the beam can be depolarized and the effect can be observed by watching the life time of the beam. No changes have to be made to the permanent setup of the transverse feedback system, and no special instrumentation is required to make the energy measurement.  
poster icon Poster  
 
WEPL022 STARS on PLC controls, factory, photon, monitoring 73
 
  • T. Kosuge, K. N. Nigorikawa
    KEK, Ibaraki
  STARS (Simple Transmission and Retrieval System) is a message transferring software for small scale control systems with TCP/IP sockets, which works on various types of operating systems. We have succeeded to run STARS server and client on PLC (Yokogawa FA-M3, CPU module F3RP61) this time. At present, PLCs are used for beamline interlock systems (BLIS) and PCs are used for monitoring system (CCS) of BLISs at the Photon Factory. Running STARS on PLC brings capability of BLIS and CCS integration. We will describe detail of "STARS on PLC".  
 
THCOAA04 Diamond's transition from VME to fieldbus based distributed control controls, photon, instrumentation, optics 124
 
  • I. J. Gillingham, T. M. Cobb, P. Hamadyk, M. T. Heron, S. C. Lay, R. Mercado, M. R. Pearson, N. P. Rees
    Diamond, Oxfordshire
  The interface lay of Diamond's accelerator and photon beamline control systems have predominately been implemented as VME based systems. Forthcoming control systems, for new photon beamlines, have requirements necessitating a divergence from Diamond's adopted design patterns, including a reduction in available rack space and the management of hardware obsolescence. To address these, a new standard based on PCs and Ethernet field buses to the instrumentation has been defined. This paper will present the new design, how the design transition is being effected and the key benefits to Diamond.  
slides icon Slides  
 
THPL007 Remote Access to a Scanning Electron Microscope using Science Studio controls, electron, focusing, synchrotron 136
 
  • D. G. Maxwell, E. Matias
    CLS, Saskatoon, Saskatchewan
  • M. Bauer, M. Fuller, S. McIntryre, T. W. Simpson
    UWO, London, Ontario
  Science Studio is a web portal, and framework, that provides scientists with a platform to collaborate in distributed teams on research projects, and to remotely access the resources of research facilities located across Canada. The Western Nanofabrication Facility is located at the University of Western Ontario and houses a variety of instruments for lithography, deposition and characterization. One of these instruments is an Oxford Instruments X-Ray System fitted to a Scanning Electron Microscope. This x-ray system has been integrated into Science Studio. This allows users to remotely access the system and upload data into the experiment management system. Remote control of the instrument is provided using a remote desktop, so users have access to the full capabilities of the instrument. Through Science Studio, access control and session management are also provided for this instrument.  
poster icon Poster  
 
THPL015 Macro package based Enhancement of SPEC controlled Experimental Setups controls, synchrotron, synchrotron-radiation, radiation 159
 
  • T. Spangenberg, K. Cerff, W. Mexner
    Karlsruhe Institute of Technology (KIT), Karlsruhe
  Certified Scientific Software's program package spec for X-Ray diffraction and data acquisition provides reliable instrument control to scientists at synchrotrons and other facilities worldwide. It’s very flexible C-like macro language provides a large number of degrees of freedom for experiment control as advantage and as big disadvantage at the same time. A large number of programmers with their own ideas and naming conventions are contributing to the growth of functionality. At the same time the risk of collateral damage by accidentally overriding already existing functions and variables grows constantly. To solve this dilemma a new object oriented like software development concept for spec is proposed. A few naming rules plus a macro package in combination with a single client-server-application expand the manageability and options to control experiments considerably. As main goal spec gets an object-like handling and a standardized user interface of newly introduced devices. A generic server-client based interface allows a smooth integration of spec in more complex control environments via TANGO.  
poster icon Poster  
 
THPL020 Control and Acquisition Software Complex for TBTS Experiments controls, extraction, target, simulation 168
 
  • A. Dubrovskiy
    CERN, Geneva
  The Two Beam Test Stand (TBTS) is a test area in the CLIC Test Facility (CTF) to demonstrate the high power RF extraction and acceleration at a high accelerating gradient, which are feasibility issues for the Compact Linear Collider (CLIC) project. In order to achieve an efficient data collection, an acquisition and logging software system was developed. All year round these systems store the main parameters such as beam position, beam current, vacuum level, pulse length etc. For predefined events they also gather and store all information about the last several pulses and the machine status. A GUI interface allows from anywhere to plot many logged characteristics at a maximum of 10 minutes delay, to go though all events and to extract any logged data. A control interface configures actions and long-term control procedures for conditioning accelerating structures. The flexible configuration of the logging, the acquisition and the control systems are integrated into the same GUI. After two years operation the critical components have shown highly fault-tolerant. Logging data are used for physic researches.  
 
THPL024 Computational Strategies in Optimizing a Real-Time Grad-Shafranov PDE Solver using High-Level Graphical Programming and COTS Technology controls, plasma, shielding, target 180
 
  • L. Giannone, R. Fischer, K. Lackner
    MPI/IPP, Garching
  • M. D. Cerna, J. Nagle, M. M. Ravindran, Q. Ruan, D. Schmidt, A. Veeramani, A. Vrancic, L. Wenzel
    National Instruments, Austin
  • P. J. McCarthy
    National University of Ireland, University College Cork
  Big physics control experiments require enormous computational power to solve large problems with demanding real-time constraints. Sensors are acquired in real-time to feed mathematical routines, which then generate control outputs to real-world processes. The underlying mathematics can be sophisticated, as even non-linear PDEs have to be solved thousands of times per second. Is low-level coding of highly specialized hardware required to meet the challenge? We report on an alternative approach based on LabVIEW that addresses demanding plasma shape control in tokamaks. A variety of input signals (magnetic coils, X-ray sensors) are combined and a constrained non-linear Grad-Shafranov PDE is solved to calculate the magnetic equilibrium in under 0.5 ms with low jitter. The off-the-shelf n-core hardware and graphical software architecture is described with a strong emphasis on the seamless interplay between development system and real-time target deployment. Numerous mathematical challenges were addressed and several generally-applicable numerical and mathematical strategies proved critical to the timing goals. Several benchmarks illustrate what can be achieved with this approach.  
poster icon Poster