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{ "url": "https://mailman.amsat.org/hyperkitty/api/list/[email protected]/email/EPZLXW27YRBZPOPGDOBHDFKR7NCJ5AXX/", "mailinglist": "https://mailman.amsat.org/hyperkitty/api/list/[email protected]/", "message_id": "[email protected]", "message_id_hash": "EPZLXW27YRBZPOPGDOBHDFKR7NCJ5AXX", "thread": "https://mailman.amsat.org/hyperkitty/api/list/[email protected]/thread/VLMW6JXCPU64CMFAJBE3WTNZTBMRUSIL/", "sender": { "address": "David.Bern (a) Engineer.com", "mailman_id": "72d9e7f6c3fe4430b68ad823493011c0", "emails": "https://mailman.amsat.org/hyperkitty/api/sender/72d9e7f6c3fe4430b68ad823493011c0/emails/" }, "sender_name": "David Bern", "subject": "[amsat-dc] Re: wanted: to borrow or buy a Yaesu G-5500 AZ-EL controller and rotor", "date": "2013-06-03T17:20:11Z", "parent": "https://mailman.amsat.org/hyperkitty/api/list/[email protected]/email/XFZGTEQJEND36Q7JAWK333XAKGFQ2NFL/", "children": [], "votes": { "likes": 0, "dislikes": 0, "status": "neutral" }, "content": "Samudra:\n\nWhat we are doing is quite simple. We are building a device that \nunderstands the EasyComm protocol\n\n http://www.amsat.org/amsat/ftp/software/win32/wisp/easycomm.txt\n\nand controls antenna rotors that use Digital Satellite Equipment Control \n(DiSEqC^(TM)) protocol\n\n http://www.eutelsat.com/files/live/sites/eutelsatv2/files/contributed/satellites/pdf/Diseqc/Reference%20docs/bus_spec.pdf\n\nThe DiSEqC rotors we are interested in are the Aspen Eagle/Pro Brand \nInternational rotor for azimuth\n\n http://www.amazon.com/Pro-International-ROTOR-Antenna-Rotator/dp/B000GIT00C/ref=sr_1_1?qid=1370254070\n\nand the Sadoun PowerTech DG380 rotor for elevation\n\n http://www.sadoun.com/Sat/Products/PowerTech/Sadoun-DG380_HH_Motor.htm\n\nDavid, W2LNX\n\n\nOn 06/02/2013 01:43 PM, Samudra Haque wrote:\n> The \"classical\" programming paradigm is to develop a solution FOR a \n> fixed set of requirements. In the case of an AZ-EL rotor, this would \n> conceivably result in the development of the modern version of \"the \n> same thing\" in use for many years, and no new discovery, essentially \n> some sort of computing device, calculating and putting out a control \n> signal that would be translated to an actuator that would turn the \n> attached boom in two axes, and therefore the antenna. Several problems \n> will plague such a design, and will be difficult to scale up or modify \n> to other systems - the torque required, the braking forces, the \n> sensors (closed loop, open loop), and the different modes of operation \n> required for low-angle passes, overhead and flip-passes. It's \n> difficult to get a computer program to solve such diverse issues. And \n> of course, the inertia of the system is almost always never taken into \n> account at the level of ham radio homebrew development efforts.\n>\n> If you agree with me upto this point ... (and with apologies to my \n> robotics and dynamics instructors at GWU) would the community support \n> a formal dynamics/mechatronics inter-disciplinary project to define an \n> actuator mechanism (6DOF) and develop a antenna positioner robot to \n> provide ad-hoc slewing of antennas? This type of project would require \n> advanced concepts in dynamics such as an equation of \n> motion/inertia/acceleration/, state vector/RK45 predictor estimation \n> and trajectory planning. Also some of the mechatronics control systems \n> would have to be modeled and the various forward and reverse \n> kinematics equations solved for different required pass trajectories. \n> And, the system would obviously have a command and control loop with \n> absolute position sensors, so our beams could be that much tighter in \n> specification.\n>\n> Warning: the math is not for the faint of heart - but the challenge as \n> I have described will an excellent framework to get high \n> school/college/AMSAT STEM syllabii in line for an graduate engineering \n> degree program.\n>\n> 73 de N3RDX\n>\n>\n> On Sun, Jun 2, 2013 at 6:51 AM, David Bern <[email protected] \n> <mailto:[email protected]>> wrote:\n>\n> Correction: I told them that hardware comes and goes but software\n> is forever.\n>\n>\n>\n> On 06/02/2013 06:03 AM, David Bern wrote:\n>\n> Louie:\n>\n> All good ideas. The Raspberry Pi or BeagleBone Black little\n> Linux computers gives us the possibility of running a tracking\n> program such as predict\n>\n> http://www.qsl.net/kd2bd/predict.html\n>\n>\n> or gpredict\n>\n> http://gpredict.oz9aec.net/\n>\n>\n> in addition to a protocol converter. I especially like the\n> idea of controlling a telescope drive. This project could be\n> useful to astronomy buffs.\n>\n> I am teaching my students a software engineering principle\n> that it is valuable to be as generic as possible; that is, to\n> be platform agnostic and protocol agnostic. It is a more work\n> in the short-term but the benefits are huge in the long-run.\n> I told them that hard comes and goes buy software is forever.\n> On Thursday, I told them, for example, that the initial\n> version of a protocol converter would take a protocol in and\n> then produce the same protocol out: to really understand a\n> protocol, you need to be able to read and write the protocol.\n> We dubbed this a \"null\" protocol converter and it should do\n> nothing correctly, i. e. bits in and the same bits out. The\n> plan is to implement a \"null\" protocol converter for the\n> DiSEqC and the EasyComm protocols that we are learning. Once\n> we have these two null protocol converters working then we\n> have the pieces to easily configure a DiSEqC to EasyComm\n> protocol converter.\n>\n> David, WL2NX\n>\n>\n> On 06/01/2013 10:04 AM, Louis Mamakos wrote:\n>\n> Perhaps this might be of\n> help:http://gatorradio.org/Manuals/Yaesu_GS-232B_Manual.pdf\n>\n> It might be cool to build the controller around an\n> inexpensive Raspberry-Pi or BeagleBone Linux controller\n> that has an ethernet interface available. You could\n> export a simple REST-based HTTP API, as well as emulating\n> the Yaesu serial protocol over a TCP connection. A simple\n> HTTP API might make testing easier, perhaps. You could\n> easily return status and debugging information if you used\n> an extensible encoding format like JSON.\n>\n> For bonus points, you could also implement the Meade or\n> Celestron serial protocol to be able to drive the rotor\n> like it was a telescope mount from various\n> astronomy-oriented programs that might be useful for\n> locating the moon, Jupiter or tracking satellites. It\n> would be a shame to build something new a modern and\n> saddle it with only an ancient serial protocol that might\n> not be the best choice for today.\n>\n> Just a thought.\n>\n> louie\n> wa3ymh\n>\n> On May 31, 2013, at 10:50 AM, David\n> Bern<[email protected]\n> <mailto:[email protected]>> wrote:\n>\n> Friends:\n>\n> I am working on a summer project with students at\n> Montgomery College, Rockville. The project is to\n> design and build a device that controls a pair of\n> inexpensive satellite TV rotors. And the device would\n> emulate a popular AZ-EL rotor such as a Yaesu G-5500\n> AZ-EL controller so it can be used by a satellite\n> tracking program such as SatPC32. Tom, K3IO suggested\n> this project at the last AMSAT-DC workshop and is\n> guiding us with this project.\n>\n> I would like to borrow a Yaesu G-5500 AZ-EL controller\n> and rotor for about three months or buy a used one so\n> we can study and understand its command protocol.\n>\n> I will pick up or pay for shipping. Please contact\n> David, W2LNX directly at\n>\n> [email protected] <mailto:[email protected]>\n>\n>\n> Thank you,\n> David, W2LNX\n> _______________________________________________\n> Via the AMSAT-DC mailing list courtesy of AMSAT-NA\n> [email protected] <mailto:[email protected]>\n> http://amsat.org/mailman/listinfo/amsat-dc\n>\n>\n>\n> _______________________________________________\n> Via the AMSAT-DC mailing list courtesy of AMSAT-NA\n> [email protected] <mailto:[email protected]>\n> http://amsat.org/mailman/listinfo/amsat-dc\n>\n>\n\n", "attachments": [] }