Update on Magnet Mover R&D and refining of mover requirements

1. Update on Magnet Mover R&D and refining of mover requirements Cherrill Spencer, ILC at SLAC, based on information from David Warner, Colorado State Report to ILC Magnet Systems Group on 24th May 2006 at FNAL

2. Magnet Mover R&D at Colorado State University (CSU) • Imperative that the ILC beams go through the magnetic center (= where B is zero) of all the quads to maintain a very low emittance • One method of ensuring this is to place every quad on a device that can move the magnet in at least 3 axes over a few mm range in tens of nm steps • Linear Collider R&D money was made available in 2003 for magnet mover development because they are extremely important to the functioning of the ILC • Colorado State University has received 2 such grants and been developing a prototype mover since 2003. They decided to start with a design based on the FFTB mover design, but exploring other shaft drive options that were more cost-effective. Cherrill Spencer, SLAC Magnet Mover Update/ for David Warner

3. Magnet mover prototype built at CSU from modified SLAC (FFTB) design Roller cam design. Long shafts mounted eccentrically into ball bearings. V blocks ride in here Shafts are each rotated by a stepper motor to make the V blocks move in X, Y and roll Cherrill Spencer, SLAC Magnet Mover Update/ for David Warner

4. Recent photos of the CSU prototype with a load Stability of mover position dominated by mover temperature. Capacitive sensor measures position Have achieved ~40nm per step resolution. Motion is very linear, range is ~3mm Cherrill Spencer, SLAC Magnet Mover Update/ for David Warner

5. CSU project has written a detailed mover status report • David Warner leading the R&D project at CSU. Have requested more R&D funds. • They have completed a prototype mover system and demonstrated a stepper motor micro-step control system and rotational encoder systems capable of achieving the original specs issued in NLC days • Will ask Warner about posting his detailed status report on our website • Needed to update the specs for the ILC Cherrill Spencer, SLAC Magnet Mover Update/ for David Warner

6. Firming up magnet mover specifications, done last week at SLAC, by BDS leader, Seryi • Only area planning to use magnet movers is Beam Delivery • 5 axis or 3 axis mover? 5 Axis • How many movers? 650 Movers including spares • Resolution? 50nm, angular resolution 0.3uR? • Range of motion? 3mm (possibly 1?) • Position stability requirements 0.1um/20 min, 1um/1 day • allowed power consumption 10-100 W/m (100W-500W) • load to be moved >500 kg? • frequency of movement every 10 minutes (?) Cherrill Spencer, SLAC Magnet Mover Update/ for David Warner

7. Understanding operating conditions:- • Operating environment (housing for mover?) • filtered air? (global or part of housing) • Air Temperature control? • How stable? 0.1°C/20 minutes, 0.5°C/1 day • What base temperature of ambient? ~105F (?) • Magnet cooling water stability 0.1°C/20 minutes 0.5°C/1 day • THESE ARE GENERAL QUESTIONS WE NEED TO ESTABLISH ANSWERS FOR, for each area Cherrill Spencer, SLAC Magnet Mover Update/ for David Warner

8. How to support the mover? • Mounts for mover Would like a 3 pt mount • Seismic protection Not so much an issue • Vibration isolation 10nm vibration motion is BDS goal for integrated motion above 1 Hz. Comes from mover, mounts and LCW • How to isolate vibration? Connect to ground as rigidly as possible says Seryi. Do NOT use Neoprene or rubber mats! • Are power, cooling, & control connection issues for the mounting Cherrill Spencer, SLAC Magnet Mover Update/ for David Warner

9. Magnet considerations: affect mover design • Magnet power connections To be designed :Weight of power cables could deform the magnet. • Magnet LCW connections? To be designed: weight • How much heat generated? (?) • How temperature stable? As stable as incoming LCW temperature • Magnet mounting points? • Where does mover touch the magnet? On magnet itself or mounting plate under magnet • Mount material (Invar)? Cherrill Spencer, SLAC Magnet Mover Update/ for David Warner

10. Other issues and future plans • Control:- Control software? Talk to John Cowardine • Active monitoring? Plan for local active monitoring • Continuing R&D plans • Increased load Active monitoring Vibration issues- borrow a seismometer from SLAC to measure vibs Move to 5-axis mover (procure parts) Understand MTBF of prototype system • What happens if power to motor goes out? • Preliminary cost estimate by Vancouver Cherrill Spencer, SLAC Magnet Mover Update/ for David Warner

11. Long-term position drift of mover and temperature measured on shaft housing Initial settling of mover Plots show the temperature of one motor mount as a function of time, as measured using our temperature monitoring system; and position of mover measured with capacitive sensor. This measurement was taken under braking torque conditions, with the mover supporting a 30 kg load. Reason for tight ambient temp specs Cherrill Spencer, SLAC Magnet Mover Update/ for David Warner