InertialTracker

class simsit.tracker.InertialTracker(*, t0, boresight0, rot_sky_pos0, rot_axis, rot_rate, mount='EQ')

Bases: Tracker

Track by rotating the boresight at a constant angular rate in inertial space.

Parameters

t0astropy.time.Time

Reference time for tracking.

boresight0galsim.CelestialCoord

Boresight at t0.

rot_sky_pos0galsim.Angle

Camera rotation angle at t0.

rot_axisgalsim.CelestialCoord or None

Axis of inertial rotation. Ignored if rot_rate is zero.

rot_rategalsim.Angle or float

Rotation rate per second. If zero, the boresight is fixed.

mount{‘EQ’}, optional

Mount type. Only equatorial mounts are currently supported.

Notes

The boresight is propagated using the Rodrigues rotation formula.

Methods Summary

get_boresight(time)	Return the boresight at the requested time.
get_rot_sky_pos(time)	Return the camera rotation angle.

Methods Documentation

get_boresight(time)

Return the boresight at the requested time.

Parameters

timeastropy.time.Time

Time at which to evaluate the boresight.

Returns

galsim.CelestialCoord

Boresight direction rotated by (time - t0) * rot_rate about rot_axis.

get_rot_sky_pos(time)

Return the camera rotation angle.

For the currently implemented equatorial-mount behavior, the camera rotation angle is held fixed.

Parameters

timeastropy.time.Time

Evaluation time. Currently unused.

Returns

galsim.Angle

Camera rotation angle.