Kur0kaze:
When the doodlebot is actually drawing, the problem doesn't occur. But only because it doesn't bounce up and down which is not part of the drawing program. The problem does not occur when the marker is all the way down because it stabilizes the doodlebot and its weight.
That's what I suspected. So it seems like you are wanting to use the DoodleBot at least partly for a use it wasn't designed for. Please provide details of what you're trying to accomplish.
Kur0kaze:
I really don't know what the problem is, was hoping u could tell me ^^.
Sure you do. The ultrasonic sensor and marker mount puts too much weight off the front of the robot. Since it only has three wheels this causes it to tip onto two wheels during sudden maneuvers.