I’m working on a project for school where I’m building a prototype of a disaster response robot with camera functions that will stream the video feed from dangerous areas. I’m using a raspberry pi 4 model b and a raspberry pi camera module, and my plan is to control the robot and stream the video from a web browser. I have most of it worked out, however, I’m struggling to find a solution to allow the robot to be controlled from a longer distance. Ideally, I would like it to be able to be controlled from up to 500 metres, but even a couple of hundred would be fine as it’s just a prototype. I’ve done some research, but as I’m not familiar with this sort of technology, I am struggling to find anything that would work and that isn’t expensive. One thing I found that looked promising was called Wifi and USB keys, but the tutorial I found this on didn’t go into detail about how it worked (the tutorial was for a drone made with a raspberry pi), or even what specifically was being used. If anyone has any information on these, or any ideas for other options that would be cheap, I’d appreciate it.
2.4GHz Radio-control, as used with RC cars, planes, drones and boats, should have enough range to cover your required distance. The are a number of features of your application you can take advantage of, such as the ability to have a large aerial on the robot, and knowing where it is approximately so that you can direct the transmitter aerial. The drawbacks are intervening terrain and buildings.
There is a lot of information about range available from the RC community, as it is obviously an important consideration, especially for vehicles that might not be recoverable if they go out of range. For example:
2.4 GHz Transmitter Shootout – Radio Range « Big Squid RC – RC Car and Truck News, Reviews, Videos, and More!
If you found information about using WiFi that would be for connecting the RC transmitter/receiver to the local network, for instance on an adjacent laptop. WiFi would not be usable for controlling the robot at the sort of distances you mention.
As Jeff mentioned, control should not be too hard, but video streaming at that range certainly is.
I’ve seen some university teams who need remote high speed links use a directional microwave link that tracks a base station, and this is on open water with no debris in the way like your application would have.
Is there scope for lowering your expectations regarding video?
The video is probably the main aspect, so if I had to lower my expectations for anything, I’d probably sacrifice the distance over the video.
I’m guessing that the 2.4GHz radio-control won’t work for the video then?