Hi, about two years ago, I started a design for a robotics class project of a AZ-EL rotator controller system, and a hardware package for the mechanism for rotating an antenna in any direction subject to mechanical stops. The system would have been able to handle regular and flip modes. I didn't do anything more than calculations, and moved on to building a classroom instructional robot then.
Lately, as I am setting up (K3GWU, the George Washington University Amateur Radio Club and Research Station) I find that the price of az-el systems such as G5500 + Yaesu AZ-EL rotors are expensive, and are not typically available on an affordable basis on Ebay or eham.net etc. Well, of course, expensive is a relative term, for a student hobby organization, it's a lot, and I guess for small ham operators it is also moderately expensive.
This may be a frequently asked topic: does any one have experienced with (tested) kit designs for AZ-EL rotors that can be made with parts from current suppliers ? I know there are a number of controller designs, but I am interested to know if there are any options for suppliers of the required gears/motors etc.
I have located several large AC motors / DC motors at my university mechanical engineering workshop, but they are not all guaranteed the same specs. I now realize if I do embark on a actual design process with my model/simulation/hardware, it would be nice to build several of these all at once to share the development cost over the production run, and ensure those who want a cheap AZ-EL system can get one. Otherwise the production cost of one heavy duty system is going to be quite high.
I hope some of you may have suggestions for me, both (+) and (-) or perhaps (~) in nature. I thought amsat / amateur radio folks have a common need to encourage homebrew activity to keep their brain cells in working condition?
I'm opening this question up to the national US audience, and welcome any discussion on the challenges of making the ever-so-important azimuth-elevation rotor. I've studied some of the alternatives: Alliance U100 and Yaesu G-5500. I think we can do better in 2013. But ideally, to allow the wide adoption of AMSAT ground stations, what price point would the system have to be to make it worth building ?
73 de N3RDX George Washington University
Hi all! Back in Fl from my trip to the great white north. A bit of trivia. It'll be 30 here overnight. BRRRRR.
An idea that Phil proposed, I've researched and found a possible part. The 9dof imu idea really makes sense. Most of these are stand alone Arduinos in and of themselves. Good example from the near east on the fave rave auction site: 271015460402
The fact that it passes the data over a serial port makes it attractive, as the setup for the device can be done by novices. Note that the data wouldn't be sufficent to pilot an aircraft, but should be perfectly adequate for heading and attitude information to point an antenna.
Having a built in compass makes setup in the field a snap. Just think. Plop the tripod down, turn it on and it will tell where you're pointed. No more gps/compass for finding beam headings.
73 de keep warm Norm n3ykf