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RH: Manual Dome Control
Views: 4479 Last Updated: 2012-02-02 23:53

The South Dome is a 10-6" Ash dome. Currently, only the upper portion of the shutter is enabled; the bottom flap does not currently move. It is partially obstructed by the power rings.

The home position is at 0/360. Currently, the dome does not rotate fully; it must stop and reverse if it reaches 0 or 360.

There are two ways to control the dome: through the engineering interface (tricky, use this very carefully and, generally, only when absolutely necessary), and the ASCOM interface.

Controlling the Dome with ASCOM directly

Note that this is different than using ASCOM with ACP or MaxIm DL; this is for an operator to move the dome to specific positions.

You can use the ASCOM Dome Control to manually tell the dome what to do. On the RH computer, this is pinned to the Windows Start menu:

This opens the program window. The Setup procedures have (mostly) already been run. Here is the full sequence of settings that you, as operator, could possibly run into:

Note that, at the time of writing, the parameters for distance from center of dome and such have not yet been measured and entered. Steve Pastor and Alfred will handle this, but in the meantime, pointing won't be too far off as things stand. You should not need to change any of these settings; if you do, coordinate with Steve Pastor before making any changes.

Important: in order to control only the dome, you can change the Selected Scope to Simulator. This is a safety item; if you should accidentally turn on slaving, no harm will come from slaving to the simulator. The real scope, on the other hand, might wind up in illegal positions. Most of the time, as long as you don't turn on slaving, it's fine to leave the telescope as the AP mount.

Note that you can also use this method to slave the dome to the telescope, although both ACP and MaxIm are probably better ways to do that.

This is what the ASCOM Dome Control Panel looks like when used with the Simulator as the telescope:

Controlling the Dome with the Engineering Interface

Caution: this is an engineering interface which means it is dangerous to use if you don't know what you are doing. Read the instructions carefully, and always stop and think before making a move to make sure that you are doing something that is safe. The software does not provide safeguards; the only safety is between the operator's ears!

Open the LabJack folder on the desktop:

This displays the contents of the folder; the program you want to run is LabJack.exe:

When the program runs, you will see a DOS box with a sculling list of lines. Each line is a single reading of dome position.

Voltage is a measurement across a rotary potentiometer. The software derives the dome position from this voltage. The Standard Deviation is used to analyze the quality of the readings; low numbers indicate high confidence that the value is reliable.  Note that the two readings use different scales for std. dev.

The Help command (?) was entered to display the supported keystrokes. 

Note that you DO NOT press return to execute a command; it is carried out immediately. So be careful with commands that make big moves. There is no support for soft limits in this software, so it is possible to move the dome to places it should not go!!!

The following commands are supported; all moves are based on time, not position!

Duration (sec)CWCCW
 0.5 -
 1 [
 2 {
 5 du
 10 D U
 20 <
Quit  q or Q 
 Stops or S  

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