Technical Innovations Digital Dome Works
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Technical Innovations Digital Dome Works
The Digital Dome Works by Technical Innovations:
Technical Innovations Digital Dome Works is a computer based dome automation package - complete with hardware and software. Digital Dome Works provides complete remote control capability of observatory including slaving to telescope.
Dome automation is the ability to operate the observatory without direct human intervention. This would include the ability to remotely operate the shutter, rotate the dome and slave the dome to the telescope. From our standpoint, automation also includes safeguards against adverse conditions (for example, bad weather or high winds). The dome must be motorized (ED - electric rotation system and ES - electric shutter system) before the Digital Dome Works (DDW) automation package can be installed. If the Dome Trak level of automation is desired, only the ED system is required.
Technical Innovations Digital Dome Works - Welcome to the World of Remote Observing!
This "welcome" is a brief story of a typical observing session with Technical Innovations Digital Dome Works. Although we assume an observing session using the Home-Dome, it could just as easily be a fifteen foot Pro-Dome. While your installation and circumstances may not match our assumptions, there will be enough similarity to help you understand the capabilities and limitations of the system. We will assume the following equipment has been set up for remote control astronomy:
- Home-Dome HD6S, using the Digital Dome Works Control Program (DDWCP)
- 10 inch Meade LX200 Telescope using TheSky?? V.6 control software
- ST-2000XM CCD camera by SBIG, using CCDSoft V.5 software for camera control
- RoboFocus remote focusing system
- Windows XP and Remote Desktop
The Home-Dome is 150 feet from the observer's control room. There is a PC-called the In-Dome Computer-inside the observatory that runs the dome, scope, and CCD software. This PC communicates to the User Computer using a local network connection. The computers and software are all running Windows XP Pro. The scope and Technical Innovations Home-Dome have already been aligned, and the system has been used recently. The user controls and communicates with the In-dome Computer using Windows Remote Desktop (software that allows the user to simulate being in the dome at the keyboard of the In-dome Computer). Some terminology may be unfamiliar to you. We attempt to use these words in context to give you a better understanding the remainder of this manual. Enjoy!
The Story: It is early twilight, and Saturn is high in the west. Everyone has gone to bed, except for Christian, (who wants to try taking a CCD image of the planet), and his older brother Jeremy. Jeremy is the lead person tonight. Jeremy turns on the control room computer, and selects the Windows Remote Desktop icon. In a few seconds, Jeremy's computer screen displays the Remote Desktop logon dialog box. Once the correct password as been entered, the In-dome Computer screen appears with icons, just as if he was sitting there.
Using his mouse, Jeremy clicks on the DDW icon. This starts the Digital Dome Works Control Program (DDWCP) on the In-dome computer. DDWCP then connects to the DDW processor in the Home-Dome. In a few seconds, DDW responds, the In-dome computer has established connection with DDW. Jeremy's screen then shows the resulting data on the main DDWCP control screen. This shows that the shutter is closed (as it should be), and that the dome is in the Home position (also as it should be).
Although Jeremy could look out the window to see the weather, he decides to check the (Optional) weather system information located on the DDWCP window. The weather information shows that the wind is only about 6-mph, temperature is 65-degrees F, and that it is apparently raining, i.e., the rain sensor shows activity. Jeremy, of course, knows that there has been no rain. He decides that the birds have again done their thing, but that the wetness measurement interlock has prevented the dome from opening. He is ready to over-ride the sensor to open the dome, but Christian reminds him that the wetness may be the result of the water falling on the dome from the lawn sprinkler. Christian turns off the water, and Jeremy decides it is safe to override the still wet sensor and open the dome.
Comment: This illustrates several important issues. The user has the ability to detect a variety of conditions that may affect operation. The rain sensor was doing the right thing: the system will protect itself (i.e., the contents of the observatory). The lawn sprinkler is a good example of a remote problem. Unexpected events will occur, and we need to be cautious in over riding protective interlocks. It is vital that a truly defective interlock be repaired as soon as possible, so that mistakes will not occur. Jeremy's decision to over-ride the sensor was valid (though he was a bit quick to do so!).
Jeremy now clicks on "OPEN" button. The screen shows that the dome shutter begins to open, and about 30 seconds later, that the shutter is full open. Jeremy will be slaving the dome to the telescope, so he clicks on the "Slave" button. DDWCP will now obtain the scope direction from TheSky software, and change the dome position to match.
Comment: TheSky and several other scope control programs will not only direct the scope around the sky, but will write this direction to a file in the In-dome Computer. DDWCP reads that file every few seconds to find out where the telescope is pointed. DDWCP carries out several calculations to find the proper dome direction, and then commands DDW to move the dome accordingly. An alternative slaving scheme (good for an LX200 only) is available. If DDW is connected directly to the scope, it can interrogate the scope and get its direction immediately, and then use this data to control the dome. This is particularly useful if the scope control program does not support the data file or similar method of operation.
With the dome slave function turned on, Jeremy is ready to turn on the telescope. But first, he remembers that the CCD camera is not running, and that it takes a while to cool down and be ready for operation. Jeremy has installed an optional remote power module that allows him to turn items on or off in the dome by remote control. He selects the User Pin button he has named "CCD Camera" on DDWCP, and turns on Channel 1 which is connected to the relay, which turns on the 120V AC power supply for the CCD camera.
Next he uses his mouse to click on TheSky icon, which opens a copy of TheSky on the In-dome computer. After a few seconds, TheSky planetarium screen shows on Jeremy's screen. He uses the menu to find Saturn, and selecting it, he centers Saturn on his screen in a red circle. Now to run the telescope! He uses the menu to select Telescope/Connect. After a few seconds, TheSky screen shifts direction, showing a white circle on some stars, indicating that the telescope is connected, and is pointed there. Jeremy again selects and centers Saturn in the red circle. He clicks on Saturn, which brings up a small data and menu box. He selects "Slew To", and the telescope begins moving to aim at Saturn. A small screen shows that the telescope is slewing, and after about 20 seconds, the white circle creeps over Saturn.
Comment. Note that Jeremy did things in the "wrong" order, he should have turned on the telescope, then selected Saturn. This illustrates the desirability of planning your observation to save time and irritation. More importantly, you will want to plan a sequence of observations to minimize time wasted slewing back and forth. You may also need to plan the sequence so that the telescope and CCD cables do not become tangled, or to avoid the telescope taking the "long way around" to get to an object. If you are nearby (as Jeremy is), fixing mistakes is usually easy. If you are 100 miles away, the solutions are more difficult!
Meanwhile, as the scope was turning, so was the dome. Jeremy could see this on the DDWCP screen, which is updated as the dome turned. Jeremy now has the scope and dome aimed at Saturn. He is ready to operate the CCD camera. He clicks on the CCDSoft icon, which after a few seconds shows the CCDSoft control window. He uses the menus to connect to the camera, and position the correct filter. Christian promptly says "you did it again, Jeremy. When you connected to the CCD camera, you forgot to enable the camera cooling. If you had, the camera would be ready now!" Jeremy groans, but turns on the camera cooling, aware that it will be five minutes before the camera is cold. "I was just testing you," he grins, glad that Christian is paying close attention.
Even though the camera is not cool, it can still be used. Jeremy selects the exposure to use, and takes an image. In a few seconds, the magic of Windows Remote Desktop brings an image onto his screen. Saturn is not there! But wait, it looks to be just off the CCD, a little to one side. Jeremy selects the telescope motion controls in TheSky, and moves the scope slightly, then takes a new picture. After several tries, there is Saturn, almost at the center of the image.
Comment: CCD cameras are incredible, but the camera-telescope combination is not a "point and click" operation. The field of view is small, and skill and practice are necessary to get good results. The sky will still be there tomorrow and next year: astronomy requires and rewards patience.
With Saturn centered, Jeremy asks Christian why he thought the camera did not show it right away. He suggests that maybe the scope is not set up right. Jeremy, who had just finally read the entire instruction manual, points out that the scope pointing accuracy is close, but that its software allows you constantly to refine its pointing. So, using the telescope controls on TheSky menu, he "synchronizes" the scope to Saturn. Jeremy suggests that Christian now try to get a good picture of Saturn. Christian takes over. He makes a short exposure of Saturn but, finds it is very fuzzy, obviously out of focus. Christian starts the RoboFocus Control Program and begins nudging the focus (remotely on the telescope) to improve the image. After each focus adjustment, he takes a new image to see the result. After five minutes, he is growing impatient; but finally the image begins getting better, and converges to a focused image. His determination pays off.
Comment: Again, remote control is not point and click focusing by remote control requires the right equipment and some fore-thought. Usually, focus will stay accurate from one night to the next. In this case, Jeremy has been into the dome, and had switched to a different set of lenses. Using RoboFocus, Jeremy can simply dial in the correct focus setting for the new setup, then refine it easily by focusing on a star (much easier than a planet!). He can even do it automatically using RoboFocus!
Jeremy now helps Christian close the dome. He uses the DDW User Pins control to activate a remote TV monitor inside the dome, so that they can see what is happening. He starts the video capture in the In-Dome computer, and views its output via Windows Remote Desktop. He closes TheSky, thus terminating the PC connection to the telescope. He goes to the DDW screen, and selects CLOSE. DDW directs the dome to turn to the HOME position, and then closes the shutter (which they watch on a video monitor). He shows Christian how to transfer his image files from the In-Dome computer to the control room PC and print them. Satisfied with their work, they go to the kitchen for ice cream.
Comment. When he closed TheSky, Jeremy did not first terminate the connection to the scope. Although in this case, such a practice caused no problem, it is far safer to turn off programs in the reverse order than was started. Jeremy did use his available video monitor to observe the closing of the dome. Although not necessary, this is good practice: one should use all the available information to understand what is going on in a remotely operated facility. But his worst mistake was that he never turned off the drive (or the power) to the LX200 scope. As a result, the scope would continue to track Saturn (its last target) until the wires are wrapped tightly around the scope, and something breaks. In this case, DDW saved him! Whenever the dome closes, if the DDW is connected to the LX200 it will send a series of commands to the LX200 that will stop the drive (unless the feature is turned off). Thus, when Jeremy turns on the observatory again, the scope will be parked, and ready for the next session!
Technical Innovations Digital Dome Works... Welcome aboard a new observing experience!
Technical Innovations Digital Dome Works Features:
- Remote operation of the observatory shutter and dome rotation motors, and can match the dome position to the telescope position.
- Provides output data to the operator, including status information on the shutter and the current dome azimuth.
- Control the dome with its own software if you are using a telescope control program that is not designed to communicate with DDW.
- If the telescope is an LX200, DDW can read the scope azimuth from the scope and synchronize the dome rotation.
- Communication between the control software and DDW is via a dedicated digital serial line or RS232 connection.
- The optional Remote Power Module provides software control of 4 electrical circuits (User Pins).
- You can operate most DDW functions via the hand control, and can even slave the dome to the scope WITHOUT using a computer connection.
- Although DDW is designed for a dome observatory, it will also control roll-offs and similar motorized facilities.
- Detects the Home position sensing when it connected to the shutter motor contacts (even if the shutter motor is not being operated).
- DDW can function in a variety of hardware and/or software configurations depending on the needs of the user and the software programs that are available for telescope control.
- The remote power module allows the user to turn on or off four 120V AC, (or 240V AC), outlets in the dome on/off remotely using the User I/O lines.
- The Reboot module uses a signal from the DDW to reboot the InDome PC in event that the PC crashes. The module comes with its own installation instructions.
- In remote operation, the user can control the observatory via the RS232 serial lines (or over a network, etc.) using the User Computer.
WARNING: The DDW is designed for remote operation by persons familiar with the system. The system controls machinery which can damage itself, other equipment, or even injure persons. Any person using DDW, or working in or using an observatory to which it has been fitted, must receive proper training in its use. Safety for persons and equipment must be a part of any observing program.
OPT Product Number: TT-DDW
To save on added expenses, this product will be drop shipped from the manufacturer. Shipping costs listed here are estimates only and an accurate figure will be given to you at the time of your order. Thank you!