It might not be as elegant or technologically-advanced as a Segway or a motorized unicycle, but this easily constructed 2-wheeled robot might be a fun project for a free afternoon. The heart of the balancing mechanism is an SPDT switch with a button cell attached that reverses the motor when the robot begins to tip in one direction. It’s not controllable and it tends to fall over quite a bit, but it’s a good starting point and could be refined by lowering the center of gravity or figuring out a simple way to change the motor speed based on how far the robot has tipped over. There are no accelerometers or tilt switches so the components could be sourced from a parts bin, and its simple design definitely leaves a lot of room for improvement.
Since last month, when the Defcon warballooning event was announced, [Rick Hill] finished building his rig and even got FAA approval for the flight. Just when everything seemed set, the Riviera Hotel management decided not to allow the takeoff from their property. So, naturally, [Rick] and his team rented a moving truck and covertly inflated the balloon inside. They launched it in an abandoned parking lot and drove through the Vegas strip. They were surprised to find that about one third of the 370 wireless networks they scanned were unencrypted.
This hack is an interesting twist that will allow you to get in or out of some parking garages when the attendant isn’t looking. Using something metal to trip the parking lot’s proximity sensor that is meant to let cars out automatically you can get into the garage or vice-versa without opening your wallet. A magnet from a hard drive might work a bit better because it is able to trip multiple types of sensors, but for this hack any kind of metal will work. This proximity sensor is a high–frequency oscillation type, so anything that attenuates, varies the frequency or stops the oscillation trips the sensor. When you can’t find a place to park, this hack will certainly impress your friends more than this method, but your street credibility could quickly turn into never lived down stories, if you end up driving over tire strips and ruining your tires, get a huge parking or trespassing ticket, or worse yet get your vehicle towed!