Raspberry Pi controlled tank goes deeper than you might think

http://hackadaycom.files.wordpress.c...0987440303.jpg
This remote control tank now takes its orders from a Raspberry Pi board. Well, actually it’s taking orders from commands pushed to the RPi board via SSH. The control scheme works out quite well. Using a low-profile WiFi dongle the RPi automatically connects to the wireless network when it is powered on. This makes it a snap to SSH into the device, and a more user-friendly controller will put a nice front-end into play at some time in the future.
But the real meat and potatoes of the hack comes in getting the RPi to talk to the tank’s circuitry. Just getting the Heng Long Tiger I remote control tank apart proved to be a ton of work as the treads need to be removed to do so and there’s a lot of screws holding it together. Instead of just replacing all of the control circuitry [Ian] wanted to patch into the original controller. To do so he spent a bit of time analyzing the signals with an oscilloscope and discovered that commands were coming in a Manchester encoded format. He established what various packets were doing, used a transistor to protect the GPIO pin on his board, and now has full control of the Tank. The final part of the hardware alteration was to power the RPi from the Tank’s battery.
After the break you can catch a demo of the reassembled tank sporting its new wireless controller.

http://hackaday.com/2012/06/30/raspb...u-might-think/