I'm setting up an educational lab which is going to have a number of cameras positioned around the room. Ideally, there would be one button somewhere which we could press to automatically start all the cameras, and when we pressed the stop button, all the cameras would send their video to a computer in the room. What would be the best setup for this? I don't want to have to walk around and press record on five cameras, then walk around and press stop, then attach 5 USB cables, then remove 5 USB cables, etc.
If your cameras have a LANC port, you can build yourself a LANC controller using arduinos:
Or alternatively get a cheap lanc controller.
Depending on the camera you are going to use, like the other replies mentioned, there might be options to control your cameras as well through a regular remote control or control over USB.
Most newer camcorders can be controlled via wifi from a mobile phone or tablet. So the easiest solution would be to have 5 mobiles phones in front of you. Press record on all of them and you are done.
Using the same technique you can also obtain their video.
Alternatively, you could connect the cameras to 5 laptops and then have a screen sharing program where you see all 5 laptops on a single computer.
You need a security/surveillance system, not a production solution. All-in-one security camera setups can do all of this. Consumer grade options can be cheap and decent quality too. I would suggest a surveillance system with at least five cameras, powered over Ethernet (called PoE, allows you to run a single cat-5 to each camera and nothing else), always on and record when there's motion only. With the right system, you will set it up once, then never have to touch it again. Just log-in over your network to view, download, or manage the videos.
If you're in the USA, Costco has some pretty good systems for fairly cheap prices too. Professional grade stuff can get expensive, but it's pretty awesome stuff.
Source: I had the pleasure of helping a friend install an advanced security system at my Father's house. This particular system ran from a standard PC with a capture card and special software, consisted of 8 cameras in two locations, and was managed locally over the network or remotely over the internet.