The Auxiliary Telescope Mount is an Altitude-Azimuth design with two instrument ports, each with it’s own rotator. The light is directed between instruments using a tertiary (M3) fold mirror.

The ATMCS (Auxiliary Telescope Mount Control System) CSC is what is used to command the motors and read the encoders to move the telescope to the desired position. The servo control loops are written in LabVIEW and are run from a National Instruments cRIO device located inside the Telescope Control Cabinet on the first floor of the Auxiliary Telescope Building. Under normal operations, the user specifies a desired target to the pointing component (ATPtg), which then translates the target coordinates into mount coordinates. The ATPtg CSC then sends PVT (position, velocity, time) vectors to the ATMCS at a frequency of ~20 Hz. The ATMCS then positions the telescope to track these positions, running an internal real-time servo loop at ~1000 Hz.

Constantly monitoring the telescope position is the ATPneumatics CSC. This CSC controls the actuators located under the M1 and M2 mirrors to hold their shape under the varying load of gravity with respect to elevation. The ATPneumatics CSC also controls other air-driven (pneumatic) systems, such as the mirror covers and mirror vents. Further details are found on the ATPneumatics CSC page.

The ATMCS also allows the telescope to be controlled remotely, from commands sent via DDS from a user’s Jupyter notebook, from an engineering user interface (EUI), which bypasses the need to communicate via SAL, or even from a hand paddle when being operated locally for servicing operations.

In nearly all cases, the user interacts with the ATMCS via the high-level ATCS class. From this class, the user can command the telescope to desired positions, targets, park the telescope etc.


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User Documentation

User-level documentation, found at the link below, is aimed at personnel looking to perform the standard use-cases/operations with the ATMCS.

Configuring the ATMCS

The configuration for the ATMCS is described at the following link. However, no changes to the configuration are expected to be performed by the user.

Development Documentation

This area of documentation focuses on the classes used, API’s, and how to participate to the development of the ATMCS software packages.

Version History

The version history of the ATMCS is found at the following link.