View Full Version : OT Robot

05-02-2004, 10:11 AM
This is a bit off topic, but I'll ask anyway. The kids at school have the mobile robot moving. Now we want to do somthing with it. I'm not into "weapons" on the bot, but I would like to transmit Audio/ Video back to a computer or TV. I have an X10 wireless tranmitter/ receiver and camera, but the unit is very directional has a small range, and it doesn't like transmitting through walls. I've been to the X-10 site but it doesn't look like they have anything better. The positive is that it is cheap and it does work.

I have an old VCR camera that still works well (I would prefer to use this) and I also have a digital video camera that I can use. I also have some CCD survailence cameras (with no documentation) Can anyone recommend a low dollar battery operated transmitter that I can use to transmit the picture from the camera? I would like a range of 500 feet or better and not be limited to line of site operation. I've seen a transmittter on E-bay that fits the bill except it is not battery operated, and I don't have a 500 foot extension cord. Converting it to DC may be an option though.

I've been to many robot sites but haven't seen what I'm looking for.

Thanks in advance, Matt

05-02-2004, 10:15 AM
Cell phone and a cpu?

I lost the site, but a kid genius was building insect type robots with cell phones and cpus. He'd download the new software as needed. He has a camera mounted on each. He was experimenting with fuzzy logic I guess since he was trying to get the computer to make decisions based on outcome.

I was impressed. I bet we see more of his work in the future.


05-02-2004, 11:10 AM
Have a look here:


There are a number of video transmitters available

05-02-2004, 01:25 PM

Looks to have 3/4 amp power requirement.

Ending about $50 puts it into the cheap range.

No clue how far it transmits.

05-02-2004, 03:22 PM
Check with the local radio/tv/satellite stores. There is a product called a video sender that transmits audio and video 500'. When I worked at the satellite shop we used to sell them for about $50.00. They broadcast on channel 14.

05-02-2004, 04:21 PM
Bernie, The transmitters I've seen that will do 500 feet are 120V AC. I supose I might be able to hack one to see if it is capable of being battery powered. Kids would like to be able to run the bot down the hall and see what's going on from my room X10 and the other CCD stuff I've seen doesn't seem to have the range or they have the line of sight problem. I found one video transmitter on an e-bay auction the fit the bill, but it was AC.

Evan, didn't see what you were refering to on the site. Some interesting educational stuff, but I missed the transmitters.

David, the IR stuff is cool. I may add that later. Could be a cool thing to see what goes on at school with the lights off. On second thought maybe not.

Thanks to All

05-02-2004, 04:40 PM
I have a 2.4 ghz wireless video system. I bought a small CCD Panasonic color video camera for it, and the TX also sends audio. I hooked it all up to my R/C humvee, and drove it around my house via the TV set.
Now I am not kidding you, All the R/C airplane flying, and everything else I have ever done, NOTHING was as much fun or entertaining as driving that little car thru the house as IF I was sitting inside it. IT blows away any computer sim you have. The Tamiya Humvee I have is 1/12th scale, and gets going up to 15-20 mph, sometimes I was able to open it all the way up in the house, then slam on the breaks make a turn and gun it again.
I chased my cat around the house.
Another time I brought the car to work, and I drove it around into people's offices, I could hear them saying, WHo the hell is controlling that?
THe wireless system I have I think is only 100 milliwatts, I get about 1000ft range straight line, 500 ft about if your shooting thru woods.
I thought about putting it in one of my airplanes, but mine requires 12v for the TX, and 5v for th camera, makes for unusual power requirements, a DC to DC converter could introduce noise that I dont want.
THe newer systems the guy sells now are all 5v.

[This message has been edited by BillH (edited 05-02-2004).]

05-02-2004, 06:04 PM
Okay, I wanna.. build one with servos on a tripod, put it into the woods to ambush bambi. Mount it on a small 4 wheeler.

Imagine.. sitting in the nice warm camper watching bambi stroll by, then machinegunning him. Perhaps I like this ideal better than the rocket launcher I was working on.


05-02-2004, 07:43 PM
check out www.supercircuits.com, (http://www.supercircuits.com,) (512-778-6950). If they don't have what you need then it isn't made. They are located just outside of Austin in Liberty Hill, Texas. All kinds of wireless A/V equipment at great prices. I have no affiliation with them but I have bought alot from them as have a number of my friends. Our local Narcs buy quite a bit of their James Bond type goodies for their unsuspecting customers.

05-02-2004, 08:16 PM
This is the guy where I got my stuff from, as a note, the stuff he sells is made by Lawmate, so could probably find elsewhere for less.

05-02-2004, 08:45 PM

The point is that an RF modulator is also a transmitter. Just connect an antenna to the broadband output of the modulator, usually 5 to 12 volts powered and you have a transmitter, cheap and simple.

05-02-2004, 10:04 PM
I understood that from the article, but I interpretted it as this might or might not work, but since it involves stuff I already have it is worth a shot.

I purchased my motor controller from a guy in PA. It runs 12-36 volts. I'm running two 24 volt wheel chair motors I salvaged from the local metal recyler. The unit can be connected to an RC car controller or a Basic Stamp. I'm thinking if you can find a sensor to detect deer scent you could probably hook up the basic stamp and your gun to the unit, and not even get out of your chair while you're sipping the wild turkey. You could watch the bot do the whole thing in front of the big screen.


05-03-2004, 07:53 AM
Woe to the man who wears doe scent in the woods.. HA HA>.
I actually have been playing with the model rocket engines.. No real explosive payload since that is illegal.

Tech:ie... You should start them kids 3d modeling. It is the future. So far, I hate to say it, cause the salesmen are aggressive butt-holes but the Bobcad looks the best.
Kinda stacking primitives to get the basic shape you want, triangles, cylinders spheres and cubes, then stitching them together.
I'm learning, but I am a old dog and this is a new trick.
ANy experience in 3d modeling is helpful in the way you think. Ayam is a free one, so is animor.. If there is any really sharp kids they need to learn DIrectX instead of the engines.


05-03-2004, 09:20 AM
We use a 3D modeling package called Inventor. It is put out by AutoDesk. Long story, but I've never had training on it. Everything is self taught. The teacher that teaches it is excellent. They learn the program their freshman year and use it throughout their HS career. By the time I get them into my Sr. Design class, they are usually more proficient at it than I am.
The program will allow you to create almost any shape you can imagine, assemble multiple shapes, create orthographic drawings and much much more. Down side is that one industrial seat is about $2000 I think. We have 100 educational seats for far less. It is also a drag and drop file system into our new CAM software(which I'm still learning).

You should see the rockets two of my kids drew and then modeled. Along with a floating launch pad. Very detailed. Both are going to excellent Engineering schools next year. I'm very proud of them.

05-03-2004, 11:58 AM

I found this. It might be what you are looking for. Not quite the range you specified but that might be improved by using a better antenna on the receiver.


05-03-2004, 08:24 PM
Evan, Looks promising! Fairly affordable and it looks like it will fit the battery operated criteria. Range is a little short, but you can't have everything.

05-03-2004, 10:46 PM
Here's a link to the Video Sender 1000' range on UHF channel: http://www.21best.com/21_best/electronic/security/video/transmitter/VideoSender.html It's alot more money than they used to be tho. These guys have a little cheaper unit (900 Mhz.) at: http://www.21best.com/21_best/electronic/security/video/transmitter/Vidi-View.html

No connection to them.

05-03-2004, 11:42 PM
As a light word of caution, not like anyone cares about it, but many of these systems actually use part of the ham band, and some are out of the ham band. My unit for instance, 2 of the channels are in the ham band, the other 2 are not.
You might need a ham license for some of these units.

05-04-2004, 06:13 PM
Still not too well here,

I want a robo-lawn mower, when you get it all figured out send me the materiel list. I'd go a couple hundred on the deal to make it happen.

It has plenty of 12vdc power, Perhaps I can mount the camera in the monkey mask to drive the thing.

Sit on the couch and drive it around the yard. Or, get a encoder on each wheel. Triangulation from a orange stripe on fence?


05-04-2004, 06:55 PM
You pretty much nailed it. Just what I was looking for. Will have to wait to build up some cash reserve. Thanks

David, There are a few places out there with the robot lawn mower already. There's a link to one off the Parallax web site. I don't see why if the wheel chair motors were meant to hall around an adult weighing 150 pounds or better, it couldn't drag a little 22" mower around. This could be fun. The guy I bought the controller from sells used wheel chair motors for $150 each. Looks like you would spend close to $600 buying the parts new/recycled. So far I've spent about$200 on the controller, batteries and misc. parts. RC car controller and wheel chair motors were donated.

The monkey mask with web cams in each eye socket pivoting on servo's would be cool. Binocular vision? , maybe some sonar units sticking out of the ears to detect sound bouncing of your fence to avoid boundaries.

Regards, Matt

[This message has been edited by Techtchr (edited 05-04-2004).]

05-04-2004, 07:26 PM
You know me, I got probably enough junk laying around to make it happen.

The basic stamp site, yes, I have about four or five BS2's still.

I have some boards I made up for the basic stamp-nand gates-tip120 transistors. Probably six or seven left.. if you want to play with one.

I think, a remote camera for about $150, futaba servo controller? .... yes it needs stamp serial demultiplexing probably. Have the camera circuit a seperate entity.

Throttle, start relay, switch, hydrostatic fwd, rev, camera up/dn rt/left? what else?

What is the range on your system?.

David's wheelchair, (he passed away last july) He had one of the new ones, it was a full pwm drive, it'd take off as fast as my 400hp camaro for the first ten feet. That is with me on it. (280+lbs)
You must have a lame one. Unfortunatly, he never got it paid for and they came and picked it up. Trying to remember the brand..
I gave away one that was so weak it'd get stuck on/off the van lift. (2" bump)


[This message has been edited by ibewgypsie (edited 05-04-2004).]

05-05-2004, 03:54 PM
The 4 channel Futaba unit will reach from my CNC room to the Art teachers room http://bbs.homeshopmachinist.net//smile.gif In feet that's about 150. I could have gone farther, but I'm not supose to leave the kids "unsupervised". The bot isn't moving yet, Kid hasn't brought in the belts for the drive. Once the belts are installed I'll do a test.

I have about 8 BS2's at school + about 4 of my own. I'd love to have more, but other's are more deserving. http://bbs.homeshopmachinist.net//smile.gif The controller I bought will plug directly into the BS2 board, and can be powered from 5 volts off the motor controller.

Hey! I just thought of something! We made our own version of the "BOEBOT"; Kids don't take the chassis when they're done because they don't get to keep the Boards. I'll trade you a Shop made BOEBOT for one of your boards.(you'll have to add your board and stamp and a few IR LED's and detectors to control it.) You can run it around with the monkey head and control it with a sony remote control. Should scare the hell out of the cat or the munchkins at Holloween.


[This message has been edited by Techtchr (edited 05-05-2004).]