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Matt Battle
07-31-2006, 11:58 AM
Hey guys-

How would one communicate between a computer and a robot long distance? like 1000, 5000 feet - 5, 10 miles.

Thanks,
Matt

DiablodeMorte
07-31-2006, 12:30 PM
Um, Internet? Or you could venture into ham radio, or cell phones/pagers

stamptrol
07-31-2006, 08:19 PM
Have a look at various wireless data radios.

For getting started, have a look at the Parallax Surelinks which will get you out to 500 to 1000 feet, in my experience.

For longer range, look at Maxstream 100 mW which I've used at 6 km ( 4 miles). For really long distance, the MAXstream 1 Watt units can get you out 20 miles or more with proper site lines and antennas.

If you're running your robot where there is Wi-Fi coverage, using a wireless receiver with the Parallax PINK module may be an option if you can live with the response time of the Internet.

Cheers

Bruce Bates
07-31-2006, 08:54 PM
Stamptrol -

At the risk of being corrected, I believe the entire SureLink series of RF products has been discontinued from the Parallax offerings. The next comments I make are purely my own, and MAY NOT represent reality, but I seem to remember some comments to this effect.

As I remember, Parallax will be offering (under their own brand name) some longer range RF products, but I can't remember the projected announcement date. Their present involvement with the announcment of, and the presentation of, the Propeller product may well have pushed this back some. So too the recent loss of some of their long term employees, may also have put this project on "hold" for a bit.

PLEASE don't take this as gospel, unless confirmed by Parallax!

Regards,

Bruce Bates

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Robert@HCC
07-31-2006, 08:58 PM
The Maxstreams are a good choice - especially because they are amazingly easy to use with stamps. 5V,GND ,datain,dataout.....thats all it takes!

Edit : I should add that the thing that really makes this simple... If you purchase the dev kit, it comes with two radios and the Dev boards. Leave one radio in a Dev board and connect to computer. Connect second radio to stamp = instant communication, with no need to worry about dealing with RS232 issues, as the Dev. board connected to the computer takes care of all that.

We are using some MaxStream 9XSTREAMs (900mhz, 100mW) at the moment, as we will be launching a CanSat package about 2 miles straight (we hope!) up...but these modules can supposedly achieve 20 miles LOS with the right antenna. Maxstream also gives a 25% educational discount for the OEM modules, as well as 50% off the development kits.

Great product , and it works exactly how the data sheet claims :

"No configuration is necessary for out-of-box RF operation.
Simply feed data into one module, then the data is sent out
the other end of the wireless link."

Of course, advanced programming is possible through extensive AT commands, if you need it done.

Alohas

Post Edited (Robert@HCC) : 7/31/2006 1:09:51 PM GMT

Matt Battle
07-31-2006, 09:43 PM
Thanks everybody for your response. I have a lot more questions. Correct me if I am wrong but doesn't long distance communication mainly depend on the power of the signal to be able to travel the distance? What if I want to communicate with something that is located on the other side of the planet? (i.e. I am in the US and the robot is in Europe?) Also can someone point me to the MaxStream website? Thanks everybody.

update: I found the link to the MaxStream website.

Matt

Post Edited (Matt Battle) : 7/31/2006 1:53:17 PM GMT

stamptrol
07-31-2006, 10:19 PM
The Surelinks are still listed with Digikey but as a non-stock item; they are manufactured by Needhams Electronics who may have the complete story as to being discontinued. In my project, the fact they weren't FCC/ Ind. Canada certified was a deal-killer. The Maxstreams are approved for license-free operation out of the box.

Long distance comm's depends on lots of variables. Distance, frequency being used, power radiated, sensitivity of the receiver, how much money have you got, and on and on.

In your posts you've gone from 100 feet to ten miles and now around the globe. Which is it? One solution is not going to cover all bases.

As a WAG, if I was going around the world, I'd use the phone system with a low-power transceiver near the robot. The robot could be controlled wirelessly while near the tranceiver which would hook to the phone system with an auto-answer modem. At home base another modem would connect to the controller. Use Skype-out and the call is free, in North America anyway.

Cherers

Matt Battle
07-31-2006, 10:41 PM
stamptrol-

Thanks for your informative responses. They are much appreciated.


stamptrol said...

In your posts you've gone from 100 feet to ten miles and now around the globe. Which is it? One solution is not going to cover all bases.


That is what exactly what I want to do. I want to start out short distance, around my house, front and backyard. Then move up to a couple of thousand feet to a mile and use a webcam to interact with environment and also be able to send commands to the robot. Then down the road from that send a robot across the ocean and be able to receive data from the robot/boat on various things (wind, temp, power, etc, etc). Yea I know you are laughing at the last one. But that is my plan for the next couple of years.

Matt

Loopy Byteloose
07-31-2006, 11:26 PM
Get a Ham Radio license and the other hams will contribute a lot too your knowledge toward this goal.
Once you get into transmission and reception by radio that is more than a few 100 meters, there are a lot of regulations to comply with. And if you want to go international, a ham license in a must.

A lot of this has been developed over many many years. Try the ARRL or Amature Radio Relay League. Both short wave and satallite communication are global. Alternatively you could use Iridium satallite phone communications to relay to a home phone and by pass the Ham Radio approach. Buy you won't have the support of a global fellowship and you will be paying bucks for each and every phone call.

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"If you want more fiber, eat the package.· Not enough?· Eat the manual."········


···················· Tropical regards,····· G. Herzog [·黃鶴 ]·in Taiwan

Matt Battle
07-31-2006, 11:54 PM
Kramer-

It’s been awhile, how you been? My knowledge in amateur radio is very limited and hopefully by the end of the day it will increase by a little. I don’t remember if you told me or not but do you have your Ham Radio license? What are the steps to getting one? This is something I will most likely be using for my big robot/boat project in the future so any info will be appreciated. Thanks

-Matt

Bruce Bates
08-01-2006, 12:02 AM
Matt -

Here is one excellent place to start looking into geting a radio amateur's license in the United States:
http://www.arrl.org/

Regards,

Bruce Bates

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Matt Battle
08-01-2006, 01:17 AM
Bruce-

Thanks for the link. It looks like all I need to ace the Technician class test is to read a couple of books that ARRL recommends unless there are some other ones you recommend? I will wait about an hour or so before I order them just in case you have better suggestions. Thanks

-Matt

Bruce Bates
08-01-2006, 01:26 AM
Matt -

Check with the largest library you have near you BEFORE you buy ANYTHING! As my dear grandmother used to say "Why buy a cow when milk's so cheap!" http://forums.parallax.com/images/smilies/smile.gif

Regards,

Bruce Bates

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Matt Battle
08-01-2006, 01:36 AM
Bruce-

I just checked with my university and the local public library branches and no luck with those two books (most likely because they are to new. Are there any books that you have found in your local library that you recommend?

-Matt

P.S. 100th post :-D

Bruce Bates
08-01-2006, 01:57 AM
Matt -

To be truthful, I am not a radio amateur, although I've thought about getting my license for about 50 YEARS! It just seems I never set aside the appropriate time for doing it.

I can't recommend any particular books, but let me pass on a important "clue". There is a cadre of radio amatuers known as "Elmers", and they THRIVE on helping new folks get into the hobby. If you know ANY radio amateur, ask him/her if he/she knows of a local "Elmer". Let me ASSURE you, you'll be in FAT CITY! I can all but GUARANTEE IT!

Regards,

Bruce Bates

P.S. 1515th post :-)

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daniel
08-01-2006, 02:23 AM
Bruce is offering wise suggestions.

Be alert to the fact that the Technician license question pool, and hence any books written to that pool, changed in Jun 2006; so be careful of buying the older version of the Technician license guide--you will learn still accurate information, but it will not "match" the test you would be taking.

Daniel KB3MUN

Kevin Wood
08-01-2006, 08:05 AM
The ARRL books are pretty good, mainly because they also offer the theory in an expanded format.

Some study guides present the question, give you the correct answer, and tell you why the answer is correct, but don't really give lessons on the theory.

The ARRL guides that I have seen will present the material, then give the questions & answers at the end. If you get a wrong answer, go back and re-read the theory section.

Loopy Byteloose
08-01-2006, 10:17 PM
No, I am not a HAM.
In my teens I really wanted to become one and studied the exam material, but being a city boy in the 1960s, my Dad didn't want the neighbors complaining about my transmissions interferring with their newly bought color TVs. He was quite right. The other problem was where to put a 1/4 wave 20 meter or 40 meter antenna in a typical San Franciscon neighborhood. Again, the neighbors were afraid that I might start an electrical fire on our roof and void their fire insurance. Or at least cause everyone to pay a lot more insurance premiums.

I guess I was a bit of a holy terror, but everyone was quite nice about it.

The older ARRL books may actually be better. LSI has caused less and less teaching of the fundamentals of radio contruction. Now you just buy an IC and assemble a board. PLLs and VCOs have eliminated the need to build your own capacitors or coils. Maybe you just by a whole unit. The Morse Code requirement is no longer a must and you can get into talking to people right away.

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"If you want more fiber, eat the package.· Not enough?· Eat the manual."········


···················· Tropical regards,····· G. Herzog [·黃鶴 ]·in Taiwan

KE5EBS
08-02-2006, 08:40 PM
Hello Matt,

You can purchase the Tech study guide from the ARRL web site. Most ham RC control is done in the 6m band, the transceiver units sold by Parallax in fact fall in the 70cm ham band, they must get away with that because of the low power of the units. BUT as a ham you would be able to hack those to a higher power say 5 watts if you wish and get a much larger range. 5 watts is what most hand held ham radio units run at. I have my Extra class Ham license, the above mentioned about the Morse Code is correct for the Tech license, if you wish to go higher though ie. General or Extra class then a 5 wpm Morse Code is still required, though the FCC has been talking about dropping that requirement for all classes. The best part of being a Ham though with what you are wanting to do, it is legal for you to tamper and hack FCC certified radio equipment such as the Parallax Transceiver kits. Normally all that is required, when doing telecommand of a unit within the ham band is that your call sign is displayed at the unit ie PC doing or giving the commands. Try looking in your local area, to see if any Ham clubs exsist, they will have a VE team that do local testing, and normally even have the study guides you could purchase from them.

Patrick http://forums.parallax.com/images/smilies/smile.gif

Post Edited (KE5EBS) : 8/2/2006 12:47:56 PM GMT

Matt Battle
08-03-2006, 02:34 AM
Hey guys,
·
Sorry about not responding and what not in the last day and a half.· my internet connection was messed up.· I have thought of some goal(s) to accomplish·for the next 3 to 4 years.· Tell me if they seem reasonable to accomplish and makes sense to do in this order.
·
1. Short distance communication (1 to· 100 feet)
·
Goals (6 months to 1 year)
1. Two-way communication between home base and “robot” (i.e. send and receive data).
2. Interact with the environment (i.e. collision detection: “bumpers”, sonar or IR, “tilt”
3. Basic Stamp Programming(C, C++, or C#)
4.
5.
·
2. Medium to long distance communication (1,000 to 10-15 miles) (improving on the first set of goals)
·
Goals (1 to 2 years)
1. Receive video
2. Receive live data from sensors (i.e. GPS, speed, direction, battery, temp, etc, etc)
3. Control “robot” from base (i.e. joystick)
4.
5.
·
3. Very long distance communication (50 miles to “as far as I can go”) (improving on the last two set of goals)
·
Goals (2 to 3 years)
1. Satellite communication
2. Testing autonomous functions (i.e. course correction, speed correction, switching between power modes, satellite following antenna, etc, etc)
3.
4.
5.
·
I might add or remove tasks from goals. This is why I left some numbers.· If you have any suggestions or questions please post them.
·
·
Hey KE5EBS,
·
Are you telling me even at the tech level I can do a lot of hacking and what not?· Wow, that is awesome.· I always thought you had to go through like a million classes.· 20+ cert. before you can do anything.
·
Thanks everybody,
Matt

KE5EBS
08-03-2006, 03:11 AM
Yes Matt,

That is what I am saying, you can as a Tech hack until your heart is content, provided you stay within your band limits which for the most part is VHF/UHF only. You are limited to the amount of wattage you can put out on a radio as a Tech but it is way more then you will ever use on a Boe-Bot http://forums.parallax.com/images/smilies/smilewinkgrin.gif. Here is a Band chart link: http://www.icomamerica.com/downloads/bandchar.pdf HF or shortwave as it more commonly known among non hams is restricted to General Class and above. As a tech I was at one time running an older tube 6m radio at 100w, so that gives you an idea of the amount of power you could play with. I live in North East Lousiana, and was able to make contact at that power with people in Cuba, Canada, and all over the US, when there were what we refer to as band openings. Now to talk to someone or something overseas would take HF it can be done on the others just not with enough regularity to be worthy of trying. I know several people running 1k to 2k watts from their house stations, General or above to do that.

Good Luck

Matt Battle
08-03-2006, 04:35 AM
KE5EBS,

You were talking about how HF can reach overseas with the right power; does that include the use of Repeaters? I am asking because I wouldn’t mind using satellites to communicate with my robot/boat. It would be a challenge and a great learning experience but at the same time a lot more work to do so. What is your opinion on this? Thanks

Regards,
Matt

P.S. I am taking it that KE5EBS is your call sign 

KE5EBS
08-03-2006, 04:51 AM
HF does not use repeaters, dont need them, there are a few I guess on 10m fm but that would be about all, to much noise on HF would keep the repeater keyed all the time, no just a normal HF rig with say 100w output and a directional antenna such as a 3 beam yagi.

oh and yes KE5EBS is my call sign

Matt Battle
08-03-2006, 05:08 AM
KE5EBS,

Wow, you’re telling me that with a HF rig with say 100w output and a directional antenna, I can communicate with my robot/boat that is crossing the Atlantic Ocean (Please don’t laugh anybody, I want to do this one day)? That is not bad.

Regards,
Matt

KE5EBS
08-03-2006, 05:10 AM
For the most part Matt, yes, but remeber radio is subject to outside interferance, ie storms, sunspot activity, atmosphere propergation ect..

Kevin Wood
08-03-2006, 06:45 AM
Although you could do it via HF, it wouldn't be the best choice. Antenna size/length would make it awkward.

One thing that you want to consider is to maintain a good understanding of the FCC regulations for the Amateur Service. There is a lot that you can do, but you can't do "just anything."

If you browse around the ARRL website, you'll find plenty of books on RF theory, design, FCC regs, etc. Also, it is worth joining the ARRL, since you will have access to their articles, and will receive QST magazine as a benefit.

Other stes that you might want to look at:

AMSAT (The Radio Amateur Satellite Corporation): www.amsat.org (http://www.amsat.org)
TAPR (Tuscon Amateur Packet Radio): www.tapr.org (http://www.tapr.org)

AMSAT deals with amateur satellites, TAPR does a lot of work with GPS tracking & reporting.

Matt Battle
08-03-2006, 12:23 PM
Kevin Wood said...
Although you could do it via HF, it wouldn't be the best choice. Antenna size/length would make it awkward.

One thing that you want to consider is to maintain a good understanding of the FCC regulations for the Amateur Service. There is a lot that you can do, but you can't do "just anything."

If you browse around the ARRL website, you'll find plenty of books on RF theory, design, FCC regs, etc. Also, it is worth joining the ARRL, since you will have access to their articles, and will receive QST magazine as a benefit.

Other stes that you might want to look at:

AMSAT (The Radio Amateur Satellite Corporation): www.amsat.org (http://www.amsat.org)
TAPR (Tuscon Amateur Packet Radio): www.tapr.org (http://www.tapr.org)

AMSAT deals with amateur satellites, TAPR does a lot of work with GPS tracking & reporting.


Kevin,

Thanks for your opinion about using HF and the antenna size. Also thanks for the links to the other sites. I did a little browsing on AMSAT site but didn’t know about TAPR. I will take a gander at them both.

Regards,
Matt

Kevin Wood
08-03-2006, 03:24 PM
To be fair to HF, it could be made to work, but there are considerations that you would need to design around.

VHF and above has its' considerations, too, but it would probably be easier to implement.

T Chap
08-03-2006, 03:35 PM
Matt Does your robot have to be wireless?

Bruce Bates
08-03-2006, 03:41 PM
Kevin -

Please correct me if I'm wrong here, but VHF has that awful line-of-sight limitation, doesn't it?

I am not a ham, but I've used commercial frequencies in business and pleasure environments. I've used both HF and VHF (marine use only) and although the HF would "punch" anywhere you needed it too, the VHF set·was such a quiet, and easily squelchable (new word!) radio that it was a sheer pleasure to use.

With the AM-HF set, if there was "weather" anywhere around, you had to keep your ear to the speaker to make sure you didn't lose any content. I can only presume that translates, in data transmission terms, to a need for data integrity checking - which isn't a bad idea regardless of the RF·format.

Regards,

Bruce Bates

Kevin Wood
08-03-2006, 04:30 PM
Radio waves at all frequencies travel in a straight line, but different wavelengths are affected differently by the atmosphere. So the net effect is that VHF & above is basically line of sight, while HF & below isn't. There is a transition region that sort of acts like either, depending on atmospheric conditions.

With the VHF and above, as long as you have enough power and a clear enough line of sight, it shouldn't be a problen to communicate.

I know that people have worked (contacted) the International Space Station & Space Shuttle with as little as 5-watts on 2 meters. I've made an approximately 40-mile contact into a repeater from a dorm rooftop with 2-watts on 2 meters.

Matt Battle
08-03-2006, 08:26 PM
originator99 said...
Matt Does your robot have to be wireless?

Hello originator99,

What do you mean about does it have to be wireless? That is the only way I can think how to communicate with the robot/boat that is 3,000 to 4,000 miles away unless you have any better ideas? (not trying to be funny)

Regards,
Matt


Kevin Wood said...
To be fair to HF, it could be made to work, but there are considerations that you would need to design around. VHF and above has its' considerations, too, but it would probably be easier to implement.

Kevin,

This is very true. That is why I am giving myself 2+ years to figure out the best route to take on accomplishing this task.

Regards,
Matt

KE5EBS
08-03-2006, 08:51 PM
And again most of what we are talking about depends at large on BAND conditions, ie are they open or not, I would think if you were to try it on HF 20m would be your best bet, but as Kevin mentioned a 20m beam is big very big, I own what they call a tribander for 10, 15, and 20m bands the boom alone on that yagi is 14' on top of a 45' tower. VHF would be easier to implement, but the range would be limited, dont think you are going to get around the world without great conditions (ie never happen). Even HF is not a sure thing, just because I can reach a country today does not mean I will be able to reach him the next. Now as to the AMSAT, I have not played around with that at all, just does not intrest me atm, but I know something about it, for one thing a person can send a message to one and have it broadcast that message at a later time ie different location of the world. Not sure to what extent or if it could be use for what you are wanting. I dont recall ever hearing about anyone doing telecommand on HF but I would guess it would be possible, nor am I aware of a band allocation for it, in HF, as I stated earler 6m (VHF) is where most of the HAM telecommand is norm used. Kevin is right, while a HAM license gives you a right to hack stuff, it is still within a guideline set by the FCC, there are rules for our hacking LOL, and there are what they call certain engineering practace plans you must follow when building equipment. One thing to note, is that if you do decide to try this remeber large antenna's take room, ie land to deploy them on, and you must be in an area where you can put one up, ie building codes ect. I would search the ARRL web site to see if anyone has tried this before, and what was their success ie learn from there mistakes, or accomplishments. BUT what ever you do, just remeber above all, as most hams will say, be safe and have fun doing it.

T Chap
08-04-2006, 02:15 AM
"How would one communicate between a computer and a robot long distance? like 1000, 5000 feet - 5, 10 miles."

Maybe I misunderstood something. I thought you were discussing 5-10 miles

Tom Walker
08-04-2006, 04:14 AM
If you have it to give away, there's always satellite phone...

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Truly Understand the Fundamentals and the Path will be so much easier...

Matt Battle
08-04-2006, 12:26 PM
originator99 said...
"How would one communicate between a computer and a robot long distance? like 1000, 5000 feet - 5, 10 miles."

Maybe I misunderstood something. I thought you were discussing 5-10 miles

originator99,
Yes, my second goal is to communicate with my robot up to 10 miles or so. I have found a couple of transceivers that would allow me to communicate between computer and robot. My third goal is to communicate very long distance somewhere around 2,000 to 3,000 miles if not more with the help of VHF, UHF, or HF.

Regards,
Matt

John Bond
08-04-2006, 09:39 PM
Hey Guys

The ArmsCorp (developed the code hopping radio your US army copied, the South African Atomic Bomb, the German and South African long range artillary, the israeli night sight system and much else) made both a small robot sized remote control tank/bomb and a remote control rocket that operated at several MILES and they were both wire guided. These strange devices uncoiled their thin steel "umbilical cord" as they went along... (you can jam radio but can't jam wire guidence). I had the good fortune to watch the trials in 1969 and the American Military Attache at the same trials was very worried by what he saw.

Obviously this is not an option these days but there are always alternatives.

Kind regards from Africa
John Bond

crgwbr
08-16-2006, 03:05 AM
I'm comming into this late, but I have a quick qustion on the Maxstream 100 mW transmitter (spaseficly the XBee-PRO™ ZigBee OEM Module).·· First, can you directly feed video from a Camera with an RCA jack output, into the datain pin of the transmitter?· Also, can a module transmite AND receive information at the same time (for example, transmit video and recieve data simultanuasly)?

Thanks

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NerdMaster
For
Life

Kevin Wood
08-16-2006, 07:17 AM
crgwbr, you might get more responses if you start a seperate thread on ZigBee.

Also, you might want to see this thread: http://forums.parallax.com/showthread.php?p=601155

Kaos Kidd
08-16-2006, 10:15 PM
Robert..
What's your cost for a dev system?

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Propeller + Hardware - extra bits for the bit bucket =· 1 Coffeeless KaosKidd
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Mike Green
08-16-2006, 10:48 PM
I don't know if this has been mentioned, but, if you plan to use this robot in an urban area, you could use a cell phone as a modem. Also, with the increasing interest in providing WiFi coverage in major cities, that could be used as well.

Matt Battle
08-17-2006, 05:29 AM
Hey Mike,

My first project I will most likely be using the Parallax 433 MHz RF modules (http://www.parallax.com/detail.asp?product_id=28180) because the robot will just be moving around my house so within the 500 foot range of the modules. My second project I was thinking about using the maxstream XTend™ OEM RF Module (http://www.maxstream.net/products/xtend/oem-rf-module.php) or another product with that range. This thread has mostly been about communicating with my third project which will be in the middle of the Atlantic Ocean most of its run. So I am looking at it being as close as one mile in the beginning to about 3 or so thousand miles away in the end. I have been asking about what is the best way to communicate with the robot/boat and a couple of people have said using ham radio, which I am in the process of looking into.

Regards,
Matt

Post Edited (Matt Battle) : 8/16/2006 9:33:58 PM GMT