BalanceBot - With PID controller and Arduino Mega

This is the next iteration of my BalanceBot. Compared with the previous video, it now has an on board battery so it's completely independent. The controller has changed from an Arduino Uno to an Arduino Mega. The Uno was running out of RAM and crashing. The Mega is much more stable. However the custom PCBs I made don't fit the Mega, so the wiring is messy, plus the Mega sticks out of the frame. Next job is to make the PCB as a Mega Shield and turn the board round long ways so it fits better. This version is also running a PID controller. Although it looks less stable than the previous video, that's an illusion. The previous version didn't have a battery, and with a battery was very unstable. The PID controller is still not fully tuned, but it's relatively stable. You can see it recovers from oscillation, which the basic controller didn't. It just drifts badly, and still falls over. But progress none the less.