YAO(1)

NAME
yao - Adaptive Optics simulation tool in yorick

SYNOPSIS

Start yao with the gtk GUI:
    yao parfile.par
    yorick -i yaopy.i parfile.par

Within yorick (no GUI, but same graphical output)
    #include yao.i
    aoread,"parfile.par"; aoinit; aoloop; go;

DESCRIPTION
Yao is a monte-carlo simulation package for adaptive optics. It includes fast core coded in C (e.g. wavefront sensing) that are glued together by yorick interpreted code. One defines the system to evaluate using a configuration file, and then run aoread, aoinit and aoloop. Yao features:

*   Shack-Hartmann and Curvature WFS, on or off axis.

*   Stackarray (piezostack), curvature (bimorph), modal (zernike) and Tip-Tilt deformable mirrors are supported. The altitude of conjugation is adjustable.

*   An arbitrary number of WFSs and DMs can be selected, with the possibility of mixing types. It is therefore possible (and easy) to simulate single DM systems, as well as single non-zero conjugate, GLAO and MCAO systems.

*   It supports Natural and Laser Guide Stars (or a mix), WFS with photon and read-out noise.

*   It uses a multi-layered atmospheric model, with geometrical propagation only.

*   The loop execution has been optimized for speed: the critical routines have been coded in C. Yorick is thus used as a convenient glue between lower levels optimized C calls. Overall, this is rather efficient: A simple 6x6 Shack-Hartmann system runs at up to 650 iterations per second on an apple dual 2GHz G5 (200 iterations/sec for a full diffraction propagation model). A 50x50 Shack-Hartmann system runs at about 3 iterations/s. A 188 curvature system runs at 25 iterations/s.

*   Straightforward scriptability to probe parameter domains.

*   GTK GUI to change some of the system parameters while the loop is running (new in v4.0). This provides an educational approach to Adaptive Optics (newbies can play with the parameters and immediately sees how the system reacts) and can also provides a quick way to investigate the stability conditions for a newly designed system, before entering more serious Monte-carlo simulations.

  Options

help,aoread
    will give you information about the syntax, parameters and keywords of aoread. See help,aoinit and help,aoloop also.

AUTHOR

Francois Rigaut, Gemini Observatory

FILES

Input files:

parfile.par
    A yao parameter file. This file follows a regular yorick syntax. It is directly included by yorick to define the structures used by yao. As it might be a little bit daunting to create a parfile from scratch, example parfiles are provided. Their location depends on the installation. Search for yao/examples (e.g. shx6x.par, curvature.par)

screen*.fits
    To simulate the atmospheric turbulence, yao needs phase screens. You can create phase screens with create_phase_screens(). They might also be included in your distribution.

Output files:

parfile.res
    After a simulation run, results are output in parfile.res in the cwd

BUGS
Lots.

LGS uplink propagation is not implemented

Shack-Hartmann cross talk between subapertures is not implemented

Many more.

SEE ALSO
yorick(1)