Author: Heron, M.T.
Paper Title Page
MOPGF098 PandA Motion Project - A Collaboration Between SOLEIL and Diamond to Upgrade Their 'Position and Acquisition' Processing Platform. 1
 
  • I.S. Uzun, T.M. Cobb, A.M. Cousins, M.T. Heron
    DLS, Oxfordshire, United Kingdom
  • Y.-M. Abiven, J. Bisou, P. Monteiro, G. Renaud
    SOLEIL, Gif-sur-Yvette, France
 
  Synchrotron SOLEIL and Diamond Light Source are two third generation light sources located respectively in France and the UK. In the past 5 years, both facilities separately developed their own platform permitting encoder processing to synchronize motion systems and acquisition during experiments, SPIETBOX by SOLEIL and Zebra by Diamond. New operational requirements for simultaneous and multi-technique scanning, and support of multiple encoder standards have been identified by both institutes. In order to address these a collaborative project has been initiated between SOLEIL and Diamond to realize a new 'Position and Acquisition' processing platform, called PandA. The PandA project addresses current systems' limitations in term of obsolescence and need for more processing power. Its design is going to be a 1U standalone system powered by a Xilinx Zynq SoC to implement a configurable set of logic functionalities. It will provide a flexible and open solution to interface different third party hardware (detectors and motion Controllers). This paper details the organization of this collaboration, sharing technical leadership between both institutes and the status of the project.  
poster icon Poster MOPGF098 [1.953 MB]  
 
MOPGF175 A Unified Approach to the Design of Orbit Feedback with Fast and Slow Correctors 1
 
  • S. Gayadeen, M.T. Heron, G. Rehm
    DLS, Oxfordshire, United Kingdom
 
  A unified control design is proposed to simultaneously determine control actions for both fast and slow arrays of correctors used for orbit feedback. By determining the interaction of the spatial subspaces of each array of correctors, spatial modes which require both fast and slow correctors can be identified. For these modes, a mid-ranging control technique is proposed to systematically allocate control action for each corrector. The mid-ranging control technique exploits the different dynamic characteristics of the correctors to ensure that the two arrays of actuators work together and avoid saturation of the fast correctors. Simulation results for the Diamond Storage Ring are presented.  
poster icon Poster MOPGF175 [0.995 MB]  
 
MOPGF176 Control System Challenges from an Upgrade to the Diamond Light Source Storage Ring 1
 
  • M.T. Heron, A.J. Rose
    DLS, Oxfordshire, United Kingdom
 
  In 2016 Diamond Light Source will replace one double bend achromatic cell of the Storage Ring with two double bend achromatic cells in the same longitudinal space. This will create an additional straight section for an insertion device (ID), thereby converting a bending magnet source point into and ID source point. Installation of the two new cells and recommissioning of the SR will take place in an eight week shutdown. The additional components in the two new cells necessitate a substantial reworking of the interface layer of control system, together with changes to all applications dependent on the physics parameters of the storage ring. This paper will describe how it is planned to manage the control system aspects of the project.
Presented on behalf of the DDBA control and instrumentation team.
 
 
MOPGF177 Robust Stability Analysis of Orbit Feedback Controllers 1
 
  • S. Gayadeen, M.T. Heron, G. Rehm
    DLS, Oxfordshire, United Kingdom
 
  Closed loop stability of electron orbit feedback controllers is affected by mismatches between the accelerator model and the real machine. In this paper, the small gain theorem is used to express analytical criteria for closed loop stability in the presence of spatial uncertainty. It is also demonstrated how the structure of the uncertainty models affects the conservativeness of the robust stability results. The robust stability criteria are applied to the Diamond Light Source electron orbit controller and bounds on the allowable size of spatial uncertainties which guarantee closed loop stability is determined.  
poster icon Poster MOPGF177 [1.023 MB]  
 
MOPGF178 Uncertainty Modelling of Response Matrix 1
 
  • S. Gayadeen, M.T. Heron, G. Rehm
    DLS, Oxfordshire, United Kingdom
 
  Electron orbit feedback controllers are based on the inversion of the response matrix of the storage ring and as a result, mismatches between the accelerator model and the real machine can limit controller performance or cause the controller to become unstable. In order to perform stability analysis tests of the controller, accurate uncertainty descriptions are required. In this paper, BPM scaling errors, actuator scaling errors and drifts in tune are considered as the main sources of spatial uncertainties and because most electron orbit feedback systems use Singular Value Decomposition (SVD) to decouple the inputs and outputs of the system, the uncertainty can be expressed in terms of this decomposition. However SVD does not allow the main sources of uncertainty to be decoupled so instead, a Fourier-based decomposition of the response matrix is used to decouple and model the uncertainties. In this paper, both Fourier and SVD uncertainty modelling methods are applied to the Diamond Light Source storage ring and compared.  
poster icon Poster MOPGF178 [1.465 MB]  
 
WEPGF137 Adopting and Adapting Control System Studio at Diamond Light Source 1
 
  • M.J. Furseman, N.W. Battam, T.M. Cobb, I.J. Gillingham, M.T. Heron, G. Knap, W.A.H. Rogers
    DLS, Oxfordshire, United Kingdom
 
  Since commissioning, Diamond Light Source has used the Extensible Display Manager (EDM) to provide a GUI to its EPICS-based control system. As Linux moves away from X-Windows the future of EDM is uncertain, leading to the evaluation of Control System Studio (CS-Studio) as a replacement. Diamond has a user base accustomed to the interface provided by EDM and an infrastructure designed to launch the multiple windows associated with it. CS-Studio has been adapted to provide an interface that is similar to EDM's while keeping the new features of CS-Studio available. This will allow as simple as possible a transition to be made to using CS-Studio as Diamond's user interface to EPICS. It further opens up the possibility of integrating the control system user interface with those in the Eclipse based GDA and DAWN tools which are used for data acquisition and data analysis at Diamond.  
poster icon Poster WEPGF137 [1.822 MB]