A Novel Method for Measuring Moment of Inertia Based on Phase-plane Analysis of Compound Pendulum Movement

The phaseplane analysis of compound pendulum movement, a process of energy dissipation, is conducted in the paper with the moment of friction being taken into consideration. Based on the analysis, a new method is put forward to measure the moment of inertia. Being not confined to the preconditions of none moment of friction and little initial angle, the method is capable of calculating the moment of inertia according to the data of the angletime relation acquired by an angle displacement sensor. Detailed error analysis is conducted, which reveals the relationship between the optimal sampling rate and the error of angle sensor, and the optimal sampling rate strategy is deduced. The method especially fits for measuring moment of inertia of largescale structure with good measuring technology and safety. 