MTRotator Motion Check

Overview

This procedure checks the motion of the MTRotator under nominal movements, issued independently from the LOVE/MTQueue or the MTRotator EUI.

Warning

This check cannot be accomplished if MTRotator is in FAULT on the CSC and/or with interlocks activated on the GIS or the MTRotator EUI. Please refer to MTRotator Recovery Procedure to clear these warnings before proceeding.

Using MTQueue & SAL Scripts

Run the maintel/mtrotator/move_rotator.py SAL script on LOVE/MTQueue using the following configuration:

maintel/mtrotator/move_rotator.py
angle: <final_angle_in_degrees>
# Final rotator angle in degrees.
# Allowed range: [-90°, +90°].

If this procedure fails, proceed to using the MTRotator EUI.

Using the MTRotator EUI

  1. Enter the virtual machine that controls the rotator (hexrot-vm01.cp.lsst.org) with your IPA account credentials, and access the MTRotator GUI.

Note

Remote Access: The How to Access MT M2/Rotator/Hexapods/Dome EUI has a detailed procedure for accessing all the GUIs in the virtual machine.

Summit Access: If you are logged into a linux machine at the summit, you can enter the virtual machine using an SSH command.

  • Open a terminal from the ‘Activities’ tab on top left, and type the following command:

    ssh -Y hexrot-vm01.cp.lsst.org
../../../../_images/Rotator_PythonGUI.png

MTRotator Python GUI (Controller Connected)

  1. Once in the Rotator Control GUI, Connect to the low-level controller (top-left), and change the Command Source to GUI.

    1. In the Command section of the GUI, select Switch command source.

    2. Under the Command Parameters go to Command Source and select GUI.

    3. Execute the command by clicking Send Command at the bottom of the GUI.

  2. Check the rotator has to following configuration in the Summary section of the GUI:

    State: ENABLED
Enabled Sub-State: STATIONARY
Fault Sub-State: NO_ERROR

    If the State is in Standby, you can enable the rotator as follows:

    1. Select State command under the Command section.

    2. Go to Command Parameters, and under State trigger select Enable.

    3. Execute the command by clicking Send Command.

  3. To move the MTRotator, select Enabled sub-state command in the Command section.

    1. Under Command Parameters, navigate to Enabled sub-state trigger and select Move.

    2. Execute the trigger by clicking the Send Command button.

    3. Then, input a value between +/- 90 degrees in the Position Cmd field.

    4. Execute the movement by clicking the Send Command button.

    5. Verify that it is at chosen value by checking the Position under Summary.

  4. If the MTRotator does not follow:

    1. Transition to Standby state (step 3) followed by the Enabled state again to reset the internal calculation of Simulink model. Then, do the p2p movement (step 4) to origin again.

    2. It might also be possible that some internal signals are not triggered in Simulink module. You can try to do the p2p movement to another point such as 1 or 2 degree position first. If the MTRotator moves then you could move it back to the origin.

Warning

MTRotator position should always be at 0 degrees in the Standby state.

  1. Once you are done moving the rotator, change the Command Source back to CSC (step 2); then Disconnect from the controller and Exit the GUI.

This procedure was last modified on Aug 13, 2025.