Behold the Wonders of Space

Planning

When undertaking the automation of your observatory, there is more to plan than just the building or dome. Among the key considerations are:

What is the reliability of my power? Can I afford to leave the roof/shutter open until power is restored?
What is the capacity (amps) of my power supply? Should I consider a single source or multiple plug-in adapters?
How will I detect deteriorating weather conditions? What actions do I need to take if conditions are Unsafe?
Will my roof damage my telescope if not in the Park Position? How do I prevent that?
How do I detect dewing/fogging conditions. How do I manage my dew heaters?

The best strategy to address these issues is to plan out the "end state" of your automation project including hardware, wiring and software. Then implement the pieces in order. It sounds simple enough, but in any System Level integration, having a plan and sticking to it, will lead to success.

At Foster Systems, we're astronomers who have designed the AstroMC line of observatory automation equipment and software. All our products are engineered for the specific needs of your automation project.

Whether it's one of our roof/dome controllers or our line of add-ons such as the AstroAlert weather monitor, the new AtPark Monitor integration system, or the ScopeShutter aperture cover, the AstroMC product family makes life easy for the serious observer.

1. Start with clean power-

A UPS that will power PC and all other equipment during a shutdown operation is essential. If power goes out, don't be stuck with your roof or dome open! Also, buy a good quality 12 VDC switching power supply (e.g. Alinco). You don't need 15 power adapters on power strips.

2. Have an overarching integration strategy-

When we use the term integration, we mean software and hardware integration. But "everything is plug-and-play, right?" Well yes, but...

Hardware- Most hardware interfaces today are Ethernet or USB. Ethernet hardware is quite interoperable, but sometimes the networking parameters are not set up right. We suggest that you avoid ethernet connections to your astronomy equipment to start and stick with USB. There are some rules though to keep in mind.

Do not mix USB 1.0,2.0 and 3.0 on the same USB hub.

Only use USB 3.0 compatible hubs, not more than 4 ports per hub.

Keep USB cables as short as possible. We keep our desktop PC next to the mount and extend the display cables.

Make sure that you plug any USB converters directly into the PC, then extend to equipment using an RS-232 extension cable.

Software-The most "open" software integration strategy is ASCOM, an astronomy software integration infrastructure available at: http://ascom-standards.org . Almost all astronomy hardware from mounts to imagers and focusers are "ASCOM compliant" which means you have some assurance that these items will work together. While there are other software integration "ideas" out there, nothing is more pervasive and reliable as ASCOM. ALL of our equipment and software is ASCOM compliant for a reason. And we strongly recommend that you adopt ASCOM as your software integration standard. You will be glad you did.

What we offer- The AstroMC Hub is available in Serial or USB capable packages as well as a Serial board level product, all attractively priced. Among the many capabilities are:

Remote Roll-off-Roof Control
Remote Dome Rotation and Shutter Control
Remote Power Control
Automatic Dew Management Control
Prime Power Safety Monitor
Scope AtPark Monitor
Text Messaging and Email Alerts
ScopeShutter Remote Aperture Dust/Pollen Cover— Now available!
AstroAlert weather monitor
AstroGraph weather trend graphing and logging software
ASCOM Compliant with Open Integration

Compatible with ACP Scheduler, ACP, CCD Commander, CCD Autopilot, SGP, TheSky6/X among others... In short, if it's ASCOM compliant, we can talk with it.

3. Make a drawing

Once you have all the pieces in mind, make a drawing of all the associated interconnections. Sounds obvious, but often skipped. Nothing stabilizes a design better than a clear sketch.

4. Build-a-Little, Test-a-Little

Start your "integration" on the kitchen table where it is comfortable and well lighted. Nothing is more frustrating than putting everything together at the observatory and having it not work. Lay out component pieces with your PC and test fit the cables and software. Only add one component at a time, each time testing all the previous parts to assure they still work. Get it all working inside first, then move it outside after labeling all the cables. This will pay off and get you in operation quickly.

Small Unattended Structure

If you don’t plan to spend time inside the structure, you can make the building small so that it encloses only your scope. One of our test observatories is 42” x 48”, and it is of sufficient size for a 16” fork mounted scope (see the picture).

If you can make the building small enough, you can place the rails lower and move part of the entire building with the roof attached. This is my design, although if I had to do it again, I’d probably place the “break” in the wall at the height of the pedestal top. This would make a much lighter structure to move. Still, with six 4" industrial wheels, running on a 4x4 rail, the cover moves easily. The structure was built in 2007 for about $500 US and is still in use today.

I’ve placed a vertical 1x8 around the inside perimeter of the rails and have attached small wheels in the horizontal plane on either side of the perimeter. This device acts as a guide to keep the cover aligned as it moves open or closed.

Such a structure is suitable for a GEM mount by parking the OTA with the counterweight down, since the entire building moves back (North) completely out of the way.

To make it move, I use a Genie chain drive garage door opener, mounted inside the structure at the back and extending out to the end of the rail assembly. I like the chain drive, because it is simple and the chain is completely inside the rail extrusion. This is good for safety and prevents rain from damaging the chain.

I use magnetic switches (same as are used for home security systems) to sense that the building is “Open” or “Closed”. The activating magnet is mounted to the cover structure and moves with it.

As for the structure door, I originally attached a screen door spring to shut it when the cover is closed and small wheels to guide the door open when the cover is rolling outward. Today, I use a DC actuator to control the opening and closing of the door.

I use AstroMC Master Control Hub to open and close the door and main cover using the our momentary pushbutton option. The cover dutifully opens when ASCOM interface commands an Open Shutter. This allows interoperability with ACP, SkyX, CCD Autopilot and any other ASCOM compliant software.

The basic design will scale up or down. An 8'x8' shell is possible since the walls are guided by the rails. This size can allow room for other equipment and supplies.

The basic design also can be scaled down. Another of our test observatories is literally 2'x'2'x2.5' and contains an 8" RC and mount. It uses 2 DC actuators and industrial drawer slides for movement.

Traditional Roll-off-Roof Structure

For larger or existing structures, some sort of motorized roof mechanism is likely already in place. In this case, the Master Control Hub, as a user selected option, offers two switched, contact closures—one for “open cover”, the other for “close cover”. The Open outlet is energized when the Open Shutter signal is received and when the Closed magnetic sense switch is closed (roof closed); the Open outlet will continue to be energized until the Open magnetic sense switch is closed by the moving cover. The Close outlet is energized when the Close Shutter signal is received and when the Open magnetic sense switch is closed (roof open); the Close outlet will continue to be energized until the Closed magnetic sense switch is closed by the moving cover.

Potential Zoning and HOA impediments

Unless you live on a large property, most amateur astronomers must live within local zoning and HOA restrictions. Often, garden sheds are prohibited by rules, regulation and local law. In these cases the very compact 2x2x2.5 sliding roof may be an ideal solution. No larger than a dog house and easily concealed by plantings, the small footprint gives the user a fully capable observatory that can be operated from a laptop inside without disturbing neighbors. Plus it is the least expensive of all Roll off Roof or Dome implementations. Spending money on optics and imager seems a good choice.

Observatory Safety

In these designs, it is strongly recommended using several switches, wired in parallel on both the Cover Open position and the Cover Closed position as well as a series of “run over” limit switches, which INDEPENDENTLY stop the roof should there be failure of the Master Control Hub. While the equipment is rugged, no equipment has 100% reliability, so a secondary safety system is absolutely required for your own safety, the safety of other personnel and for your equipment.

Our equipment has extensive telescope safety features to prevent damage, but ultimately, it is the user's responsibility to provide necessary safety interlocks.

Also, it is strongly recommended using a couple of simple webcams to monitor operation remotely for safety of equipment and personnel.

Finally, as Bob Denny (Creator of ACP) always warns:

“Do not depend on ACP or any other computer program to assure that your telescope is parked if closing your roll off roof or clamshell would strike the telescope in an unparked condition! Consider this fair warning. You really need to install a limit switch or equivalent that provides basic safety without computer involvement!”.

Dome Primer

Domes are the most well known type of observatory. They come in all sizes from 3 feet diameter to 50' and beyond. There are advantages to a traditional dome, but there are two issues that may give the amateur pause-- expense and complexity.

Domes can be 5 to 10 times the cost of an adequate Roll off Roof and the mechanical and software complexity is significant.

Having said that, there is something satisfying to some amateurs and some professionals in carrying on the historical tradition of dome observatories.

When shopping for a dome, there is fundamentally no difference in function or features despite what the brochures claim. All domes rotate; all domes have an opening shutter. All domes must be able to track the movement of your telescope... regardless of whether that movement is manual or motorized. It all depends on what you want.

Personally, I would want a dome that can be manual but is upgradable to motorized in a straight forward way (an upgrade kit). You may find that "muscle power" is all you need, especially if you plan to be inside the dome during use. Later, you may see the advantage of automation in order to maximize "imager time on target" and upgrade to motorization and full automation (computer driven). While we can't provide motorization kits (all the mounting brackets are custom to the dome), we do sell ASCOM compliant rotation controllers and shutter controllers. Our controllers have digital radio communications and channel selection when used in a complex of multiple domes.

I'm not that enthusiastic in so-called low cost domes since they are manual and practically, cannot be automated. I'd rather investigate an adequate roll off roof. Our ASCOM compliant controller is also less complex (software/hardware) and less expensive.

All other factors considered if you want a dome, I'd suggest you start by studying the product of ExploraDome company. You can find them here.

Automation

Integration & Tools

Many enthusiasts have extended our equipment and software to provide required capabilities in order to take full advantage of remote and automated observatory control. Although suppliers have no affiliation with Foster Systems, LLC, they do offer capabilities that integrate well with Foster Systems products.

We provide here links to some of these suppliers to assist you in planning and implementing your observatory. You can gain help, advice and support on our Forum where we've established a special section for integration questions and help from others to make your observatory a success.

Foster Systems