In the previous papers, we reported the motion control methods and experimental results on the parallel bicycle which is composed of a double inverted pendulum type body pivoted on the axis of parallel wheels and a pair of controlling arms suspended from the upper end of the body. The inverted pendulum type parallel bicycle can stabilize itself skillfully and move according to the servo reference by means of its controlling arms or the wheels. However, it cannot negotiate uneven paths such as stairs. For travels on uneven paths, we have developed a new type of parallel bicycle with an articulated joint connecting two divided body sections. This bicycle can change its configuration by folding its body, and can adapt itself to different environments or applications. Some control methods for the new vehicle and experimental results are described in detail in this paper.
On stabilization of a triple inverted pendulum via vibration of a support point with an arbitrary frequency