On the stability of two-wheeled vehicle balancing passive human subjects

A two-wheeled vehicle balancing a passive inverted pendulum is analyzed based on an experimental device. The corresponding mechanical model is a wheeled double pendulum, where only the position of the lower pendulum is measured. The sampling effect of the digital control is modeled as a zero-order hold. It is shown that the stabilization of the upright position is possible by proper choice of the control parameters as function of the sampling period of the controller. The model can be applied to analyze the behavior of wheeled vehicles with passive human subjects standing on it. The results are demonstrated on small-scale experimental realization of the system.