Active Balancing Control for Unmanned Bicycle Using Scissored-pair Control Moment Gyroscope

A control moment gyroscope (CMG) is capable of generating strong restoration torque with a relatively small-sized flywheel by changing the direction of flywheel momentum. Because the CMG is energy efficient, it has been used for active balancing of a bicycle that has an unstable equilibrium point in its dynamics. A single CMG generates not only the restoration torque component but also an additional unwanted torque component. In contrast, a scissored-pair CMG cancels out the unwanted torque and doubles the restoration torque. This study deals with active balancing to implement an unmanned bicycle by using a scissored-pair CMG. Based on the inverted pendulum dynamics model of a bicycle, a linear quadratic regulation algorithm is presented for balancing control. In order to investigate active balancing, a miniaturized bicycle system is developed, and its 3D solid model is created to obtain the parameter values of the dynamics model. Two kinds of disturbances exist that can cause the instability of a bicycle with an unstable equilibrium point: impulsive external disturbance and static constant disturbance. Experimental results show the performance of active balancing for a bicycle with a scissored-pair CMG against those disturbances.