They jumped in and started playing with an AR drone, a hackable quadcopter that you can control with your phone. The AR drone runs Linux on board, has sonar sensors, and two built-in cameras. The only problem with the AR drone is the fact that you only get a short time on each battery. While you could theoretically purchase a whole bank of batteries and cycle through them, it could be difficult to develop and test while constantly swapping batteries. Especially if you add any power-sucking peripherals, like a Dropcam.
Tara and Sean tackled this issue by tethering their AR Drone. By modifying the power connector, they were able to run the AR drone from a PC power supply and 30 feet of 14-gauge speaker wire. They can now indefinitely run the quadcopter while they test things out and play, at least as long as the motors will run. With only one week at the facility, they didn't go beyond mounting the Dropcam and the figuring out the tether, but that isn't too bad!
You know how bench supplies always have two positive terminals and two negative terminals, and they're always coupled with big (E on its side shaped) shorting links. Well if you remove the shorts, then, run your two thick wires out to the load and two thin wires back to the sense inputs, the power supply will automatically compensate for the voltage drop in the thicker wires.
It seems there is some time before the quadcopter decides it is dead. Can you control the power supply to raise the voltage as a function of the current (and resistence) so that the voltage at the quadcopter is constant (e.g. not at the power supply).
January 2016 Cartoon Caption ContestBob's punishment for missing his deadline was to be tied to his chair tantalizingly close to a disconnected cable, with one hand superglued to his desk and another to his chin, while the pages from his wall calendar were slowly torn away.122 comments