Bending mode data for Rubin Observatory Simonyi Survey Telescope

<p>Bending mode data for Rubin Observatory Simonyi Survey Telescope</p> <p>Bending modes sags are represented as sums of Zernike polynomials and a bicubic spline for each mirror.</p> <p>Source of bending mode data is: https://github.com/bxin/ZEMAX_FEMAP/tree/main</p> <p>To resolve an extrapolation error in previous legacy bending modes, new modes were created by:</p> <ol> <li>Reading original unit load cases</li> <li>Weighting unit load case forces to match previously determined bending mode forces</li> <li>Applying above weights to unit load surface deviations</li> <li>Decomposing into Zernikes + bicubic splines</li> </ol> <p>The corresponding actuator forces for these bending modes can be found in:</p> <ul> <li>https://github.com/bxin/ZEMAX_FEMAP/tree/main/0M1M3Bending/2bendingModes</li> <li>https://github.com/bxin/ZEMAX_FEMAP/tree/main/1M2Bending/2bendingModes</li> </ul> <p>Representative files:</p> <ul> <li> <p><strong>M1M3_bend_zk.fits.gz</strong>: Zernike coefficients (in meters) for M1M3 sag perturbations.&nbsp; 20 modes x 29 coefficients</p> </li> <li> <p><strong>M1M3_bend_forces.fits.gz</strong>: Forces on each actuator for each bending mode.&nbsp; 20 modes x 156 actuators</p> </li> <li> <p><strong>M1M3_actuator_table.fits.gz</strong>: IDs and locations of actuators.</p> </li> <li> <p><strong>M1_bend_coords.fits.gz</strong>: Grid coordinates&nbsp;for bicubic spline nodes on M1. 2 dimensions x 204 points</p> </li> <li> <p><strong>M1_bend_grid.fits.gz</strong>: Bicubic spline coefficients on M1.&nbsp; First dimension is split into z, dz/dx, dz/dy, dz^2/dxdy.&nbsp; Second dimension is 20 bending modes.&nbsp; Third and fourth dimensions are x and y grid locations.</p> </li> <li> <p><strong>bend.yaml</strong>: YAML file indicating which grid coordinates, grid, and Zernikes to use for each mirror.&nbsp;Also indicates inner and outer radii of annuli for Zernike components, and the ordering of modes to use inside of the batoid_rubin package.</p> </li> </ul> <p>Additional files for M2 or M1 and M3 separately follow the same pattern described above.</p>