MONALISA Compact Straightness Monitor (CSM) simulation and Calibration

1. MONALISACompact Straightness Monitor (CSM) simulationand Calibration Summer Project 2008

2. Compact Straightness Monitor • 6D position transferred from left to right • Integral use of sturdy endplates required. • Preliminary simulation results of CSM Resolution: • sy:10nm • distance meter resolution: 1nm = Resolution in z-direction • Positional change of optics components with respect to each other: 1nm. That’s the challenge! • Assuming launch and Retro-Reflector form perfect points 10cm

3. Compact Straightness Monitor • 6D position transferred from left to right • Integral use of sturdy endplates required. • Preliminary simulation results of CSM Resolution: • sy:10nm • distance meter resolution: 1nm = Resolution in z-direction • Positional change of optics components with respect to each other: 1nm. That’s the challenge! • Assuming launch and Retro-Reflector form perfect points 10cm

4. Titanium Compact Straightness Monitor Calibration Constants • Launch not from single point: • We don’t exactly know where this point is • We don’t know the relative position of the two launch heads that form a pair with respect to each other • We don’t know the relative position of the four launch pairs with respect to each other.

5. 10cm Calibration • Make mathematical model for perfect system • Implement Model in Matlab • Graphical representation • Solve system • System with 3 points can be solved analytically • Needs minimization since measurements are not perfect: Method of Least Squares. • Next one could include errors on distance measurements • Finally lets assume we do not know the relative position of the 4 origin circles with respect ot each other. Calibration Method: • Move target around (on motion stage) where one knows exact position of target motion • Implement this in mathematical model and solve for position of 4 circles This is hard to start That is better/easier

6. Calibration • Make mathematical model for perfect system • Implement Model in Matlab • Graphical representation • Solve system • System with 3 points can be solved analytically • Needs minimization since measurements are not perfect: Method of Least Squares. • Next one could include errors on distance measurements • Finally lets assume we do not know the relative position of the 4 origin circles with respect ot each other. Calibration Method: • Move target around (on motion stage) where one knows exact position of target motion • Implement this in mathematical model and solve for position of 4 circles This is hard to start That is better/easier

7. Calibration • Make mathematical model for perfect system • Implement Model in Matlab • Graphical representation • Solve system • System with 3 points can be solved analytically • Needs minimization since measurements are not perfect: Method of Least Squares. • Next one could include errors on distance measurements • Finally lets assume we do not know the relative position of the 4 origin circles with respect ot each other. Calibration Method: • Move target around (on motion stage) where one knows exact position of target motion • Implement this in mathematical model and solve for position of 4 circles • Now one needs to do the same thing in 3D for the real system • Move one platform with respect to the other • Links to Least Square description and procedures used to calibrate LiCAS can be found on web page. 10cm