I am trying to control a robot which has a pan tilt camera on a setup like the lynxmotion Pan tilt assembly. I need to find a way to send a clear video signal approximately 1000 feet under varying urban environments from a mobile wheeled robot. I am using a 2.4 GHz or 1.2 Ghz Video Transmitter
(1 Watt Max FCC Limit without a liscence). I am now looking for a RF hobby Radio to control the robot and pan tilt assembly with a minimum of 4 Channels I have tried AM, FM and 2.4 GHz Radios, both have interference issues and I am wondering if anyone else has tried this and what you recommend for simple wireless control/Video Transmission.
I hear PCM radios are good for robotics/UGVs?..
Please look at my bots here:
www.inspectorbots.com
Thanks
Chris
The below discussion might be of interest. I think a wifi solution would be the best for a serious project. Put a small computer on the bot and use wifi to communicate with a remote control computer. Has pretty much every thing needed at a reasonable cost.
The potential problem with Wifi is the limited range. Any of the standard variants (802.11b/g) are generally listed with an average range of about 300ft. I think 802.11n is listed as almost ~1000ft average range, but so many things affect relatively weak wifi signals that I’m not sure how reliable it would be in an urban type environment. (Do you have line-of-sight? Will the signal be travelling through metal or concrete? etc.)
Wifi range can often be extended with directional antennas. Also, outside of the home/business network standards, wifi can actually be a long range solution. Requires more power and specialized, larger, components though.
My first idea would be to check out the Spectrum/DSM radios and transmitters. (Or Futuba FASST systems) You said you already tried 2.4ghz radios. Were they spread spectrum though? Range of these radios is listed as ~9000ft. I would expect they’d be less susceptible to interference too. (Though I don’t know if they’d cause interference for a nearby signals, like a 2.4ghz video signal.) More info on the Spectrum DSM technology: lynxmotion.net/viewtopic.php … hlight=dsm
If you haven’t already tried DSM, might be worthwhile. If you have and that still wasn’t enough, then I don’t have any other ideas and I would guess that any workable solution won’t be an off the shelf item.
HI, Thanks for your feedback, I am working on developing a UGV (unmanned ground vehicle) for rapidly deployed tactical use (think SWAT) In urban environments there is always concrete, metal, buildings and walls.
Do you know of anything which is not LOS (line of sight) that can provide a clear reliable video signal from a moving transmitter?
I like the WiFi idea, but often there is no wifi network, and its not convenient to set one up. I have both a Futaba Fasst and the Spektrum DSM, I havn’t had much luck with either. With the 1.2GHZ Video TX and 2.4 GHz Radio I get lots of snow. With the 2.4GHZ VideoTX and 2.4 GHz Radio I get horizontal banding as soon as I turn on the Radio. I am testing this first in my basement shop. I drive the vehicle around a 25 foot long wall…
I don’t have any experience with this myself, but I have seen a number of videos on the Internet where people are receiving video signal while flying their RC helicopters, etc. I’m sure you have too. e.g. nitroplanes.com/wosmlora24gh.html . Maybe they aren’t using a wireless 2.5ghz video with a DSM radio though.
I’m surprised you have interference between the 1.2ghz video and the 2.4 ghz radio. I’m totally guessing, but I wonder if a 5ghz video solution would solve the interference problem?
Fwiw, here are some higher end solutions. Not sure how directional they are though. wirelessvideocameras.net/cat … _minilink/
maybe a cell modem… assuming a cell phone data service is available. I don’t know how well real-time motion video is going to work on that though, if they even allow it. the value behind the suggestion though is that cell phones are designed to deal with all the issues of motion, interference, reflection, and the multi-path signals that you will encounter in an urban environment so maybe there is something using that technology you can apply.
I like the cell phone idea. I’m not sure about the video quality, or where to start, but you’re right; they were designed for this same problem, maintain a clear signal from a moving source in an urban environment inside, outside, rain or snow. And the network is continually expanding…
The thing with UAV’s is they are line of sight, and its usually a clear shot from air to ground. easier in some regards.
If you want a communications setup based on the cell phone systems, you might look at the below G3 computer adapter. Various cell phone providers offer these (but you will pay monthly fees to use cell systems). Bottom are previous projects similar to yours. Reality check: If the the type of communications setup you want were easy/cheap, everybody would already be using it.
lynxmotion.net/phpbb/viewtopic.php?t=1870
lynxmotion.net/phpbb/viewtopic.php?t=2584