Just a short video of the Maxbotix EZ0 sonar sensor hooked up to the helicopter. The code running on the Picaxe simply reduces the pulse-width to the servo by 20% if something is closer than 30cm. This is too close for actual use, but demonstrates the concept.
I was going to have a lot more to show from today, but 20 seconds after I finished filming this, the batteries in my rc controller went flat, the helicopter took on a mind of it's own, flipped over and proceeded to rip off the top rotor...