LCLS Single Undulator Test Plan

The first two weeks of the test shall be called “Short Term Tests” and there will be an additional 6-8 weeks for the “Additional testing and Evaluation Period”. The Short Term tests will be dedicated to gathering enough information to prove the prototype components and use that information to assist in the final design reviews and procurement of production components. A list of milestones from the master plan for this initial time of testing are given below.

In parallel with these tests a completely separate “Long Term Test" (Drawings of the long-term test layout) facility will be constructed. This area will be dedicated to an ever evolving production undulator and its’ associated short and long break sections. Half of the existing APS EAA RF area has be designated for this work. To start with the system will be constructed with prototype undulator components which will be subsequently swapped out for production components as they become available. The test area will have a full scale, twenty foot long, half-section mock tunnel. The undulator components will be located in exactly the same proximities as they will be located in SLAC’s U.H. Tunnel. It is expected that this facility will remain in place through the LCLS commissioning stages.

SUT Collaboration ANL/SLAC
Provisional dates for collaborative visits from the SLAC team have been based on the project schedule. It is expected that SLAC engineers will become involved as and when hardware is either delivered or installed at ANL. At least five SLAC engineers have been identified to collaborate during the SUT. Visits will be coordinated through Geoff Pile and Rodd Pope. As an example the following three areas have been identified where significant collaboration will be required.

Hydro Leveling System and Wire Position Monitor systems
The designs for the Hydro Leveling System and Wire Position Monitor systems are not yet fully developed. Collaboration efforts are in effect between ANL and SLAC engineers and their designers. It is anticipated that dummy/prototype equipment will be fitted to the SUT during the middle of May 06. Responsible collaborators are  Franz Peters, Catherine LeCocq and Emil Trakhtenberg and Geoff Pile.

Alignment Activities
Alignment activities during SUT construction and testing will take place on a continual basis. Primary responsibility for this effort lies with ANL. Collaboration efforts are in effect between ANL and SLAC engineers. Responsible collaborators are  Horst Friedsam and Catherine LeCocq.

Magnetic Measurements
No significant magnetic measurements are planned but magnetic testing of the 1st Article Undulator magnet(s) will be performed in the same magnet measurement facility (MM1) in parallel with the SUT tests. Collaboration efforts are in effect between ANL and SLAC engineers. Responsible collaborators are  Isaac Vasserman,  Zack Wolf and Catherine LeCocq.

March to June 2006 Construction and Testing Schedule ( link to master schedule)

The following list provides a preliminary overview of the activities and time estimates associated with the Single Undulator Test (SUT) testing program.  The SUT will be assembled in MM1 to the point where testing can begin by the last week in March of 2006 (early start would have been 2/27/06).

Testing will start at approximately ninety percent completion of SUT assembly.  At this point five days are allocated for initial testing of Kinematic Undulator Replacement with the dummy undulator and then a combination of final assembly and testing will follow. It is expected at approximately four weeks into the testing that the dummy undulator will be kinematically changed for the Hi-tech 1st article. It is planned that at the end of the Additional testing and Evaluation Period the Metalex 1st article will also be tested for Kinematic Replacement.  

Since all of the motion system can be controlled remotely, tests may be initiated and conducted during non-work hours including evenings and weekends.  The total duration of all of the testing activities, system analysis, and integration activities is expected to last a total of 6-8 weeks assuming there are no major problems.

Discussion

Calibration of the Cam mover system will be rather involved and will require some time to successfully complete.  First, each Cam mover must be individually “zeroed” to find the position 90 degrees from the extremes (maxima/minima) for the eccentric shaft.  After this has been accomplished, distances from each of the Cam centers to the linear potentiometers and to the quadrupole center must be added into the software.  The degree of accuracy for these steps will determine how accurately the Cam system can locate the quadrupole center when the system is commanded to move to a point in space.  All of the linear potentiometers must be “zeroed” to locate the girder as a rigid body in 3-D space relative to some geometric center. 

Motion repeatability testing for the five degrees of freedom (X-translation, Y-translation, Pitch, Roll, and Yaw) includes cyclic tests for possible motion combinations.  Cyclic testing shall be conducted from a start point to and end point, and also about a start point to two equal and opposite distance end points in order to include the various combinations of system backlash into the measurements.  In the case of Yaw testing, visual inspections of the cam bearings and bearing surfaces will need to be conducted to verify that the combination of bearings chosen for the Cam mover system provide sufficient freedom of motion to minimize damage to the bearing surfaces.  Repeatability testing must be completed prior to motion accuracy testing since accuracy testing involves not only the stack up of mechanical backlash and tolerances that determine repeatability, but also include possible errors from the Cam mover system calibration.

Thermal infrared imaging will be used to assess the effects of motor heating on the system.  Although, in general, motors will not be continuously powered for long periods of time in operation, we still need to note the effects to the system under these conditions.  Each motor will be evaluated to see the thermal effects imposed on the system from long term operation.

After all of the motion repeatability testing has been conducted and the bearing configuration has been verified to perform adequately, motion accuracy tests shall be conducted to assess the point to point accuracy in changing the quadrupole position.  Equations have been generated that will allow command and control of the Cam movers to place the quadrupole center at a specified position.  A series of tests shall be conducted to assess the motion accuracy in performing point to point motions using the five degrees of freedom of the Cam mover system. 

Similar to the Cam mover system testing, the undulator roll-away system shall also be tested in a cyclic fashion from a start point to and end point, and also about a start point to two equal and opposite distance end points in order to include the various combinations of system backlash into the measurements.  Both repeatability and accuracy will be assessed for the various motion combinations.  In addition, girder roll shall be evaluated as a function of roll-away position in order to determine the effects this will have on the quadrupole position during the roll-away cycle.

Logbook and Test Results

A Hard bound Log Book (pic 1, pic 2)will be kept in MM1. This log book is intended to serve as a reference or index to the electronic information produced during assembly and testing. Daily (and even times) events, assembly/test notes and results must be entered into this log. It is also useful to use the log to pass on general information for all co-workers to read.  It is expected that CAMs review this log so they can collect/collate the electronic data from their team. The pertinent electronic information will be posted to the ANL LCLS web site as “SUT Assembly and Test Results”