Perhaps we should be looking into advancing the propulsion systems of MAVs, small UAVs by using magnetic propulsion to spin the propellers. When testing a UAV by trying to fly it under the canopy of trees or around sparsely populated tree areas or in cities with streets and housing we may find we have difficult issues. If the aircraft as proper angle of attack you might be able to slow it down, reverse the propeller spin, do a level flight tail slide, reverse the propeller again and fly right out of a box canyon or alley way. Or take pictures of your enemy, turn around and leave?
In the case of a MAV you could have wings like a dragon fly and simply back up without turning around and putting your vehicle in a slightly different path than before and try to switch the navigation code to fly back out and remember where you came from, because that takes significant memory and that right now takes significant space meaning you add weight to the MAV whose payload may only be low double digit ounces or less. By backing up and memorizing only the last 200 let's say commands from the central network, it could easily command the tiny 15 cm MAV to reverse.
By using magnetic propulsion the delay from going to forward speed by the propeller to zero to reverse would not be significant in time, so the MAV would not stall out, because the reverse direction would be nearly instantaneous. Also realize that magnetic propulsion maybe less of a draw on the batteries to fly the unit. Which maybe able to take energy from this premise:
The optical flow sensors with minimal storage could remember the flight path and/or commands of 200 or so airfoil surface movements. You see the difficulties and challenges of MAVs working in close proximity to obstacles will be a challenge of the future.
"Lance Winslow" - If you have innovative thoughts and unique perspectives, come think with Lance; www.WorldThinkTank.net/wttbbs