Fast passing over steps with unknown height by a `variable structure type four-wheeled robot´

We develop a wheeled robot, called a `variable structure type four-wheeled robot´ which, with a simple structure, has the ability to pass over a step. We have realized its dynamics for passing over a step of known height. In this paper, we consider the control of dynamic passing over steps of known heights. We propose the method for planning a dynamic trajectory by evaluating the robot´s stability against falling down in landing. We also confirm the possibility of detecting the height of the step using an existing rotary encoder without adding any external sensors. As the result, we have successfully realized an experiment of this robot going up steps whose height is unknown within only four seconds