I have been looking for a method to send control instructions and recieve video from my robot. From what I've read xbees wont be able to do this with a reasonable fram rate. Im am looking for a nudge in the right direction as to what sort of hardware I can use...
I found these on e-bay, they're resonably priced, However Im not too sure if they will get the job done.
The first pair looks interesting. The claim is that they are good for massive data transfers, although the quoted speeds do not support that claim. 9600 baud max will not support any kind of video. Even 115200 is too slow.
A search of the (old) forum for CC2500 will reveal that no one has successfully used that chip with an Arduino.
if you are going to have any sort of 802.11 wireless to this device, might i suggest a nifty little ip camera. not too badly priced and can be found in decently small sizes. Or maybe even use a usb webcam and send that over the wifi connection. if distance is an issue, you could use a 5.8ghz antennae and some compatible 5.8ghz wifi chip. but then project costs are getting kind of high. I'd be interested in if there is a solid way of sending video over a wireless link except wifi
My plan is not to directly interface video to the arduino, I was thinking a uart camera would use the tx on the wifi module and the rx would go to the arduinos serial input for movement instructions. The other wifi transciever would be connected to a pc.
Sure Electronics have a biggier wifi module that could support video
thats kinda what i was suggesting, i know i've seen a lot of projects involving the arduino/ethernet shield/wirelessrouter...in fact right now im working on a circuit board that combines the ethernet shield and arduino main board all onto one board, so then all you need is the router
I've been experimenting with AirStream A/V modules for audio and video, at the same time as having XBee operating.
As well as Bluetooth and all the WiFi going on here, I've not noticed any video problems.
I picked up an MSI TV tuner/video dongle for $50 and I use that to digitise my received video, then I use VLC to stream video around my network.
There is no reason to have all your data going over a single RF link.
Thanks for all the info guys, yeah I think the ethernet shield, router and ip camera will be the best way to go with this. Theres actually some neat foscam ip cameras that are relitavely cheap and have built in pan & tilt on ebay.
That is a 2.4ghz radio transmitter designed for long range (1000m) video sends and receiver to suit, I have not got one of these, but you might be able to use the uart onboard to get some telemetry over them. Or, get one of the 900mhz radio modems from Digi (the maker of the Xbee). These WILL get the job done as they are what the people who build UAV setups use for their groundlinks, they are field proven. They are, on the other hand about double the price.
I have an idea that might be helpful here but it will require some additional learning and an amateur radio operator's license. What I'm talking about is a small transceiver that uses the 2 meter amateur radio band. There are a few variants of this but the specific one I'm talking about is the Dorji DRA818V. It's capable of 1 watt output and is about the same dimensions as an Arduino nano. A technician class amateur radio operator's license gives you the ability to legally use the full 2 meter band for both voice and image transmissions. Of course there are data rate limits on every amateur radio band, so I don't know if you would be able to stream video but you could probably transmit still images and there's more than enough bandwidth to transmit instructions and receive telemetry.
This is something I really want to experiment with myself as the thought of designing a small robot that could be controlled remotely from some distance using a radio sounds really cool and I'm already a licensed operator. If I come up with something I'll be sure to make a post in the Arduino forum.
If you're planning to use the DRA818V for anything besides receiving, please take the time to get your license. There are plenty of study guides online and in the united states it only costs $15 to take the exam.
