Obtaining Optimal Results with Filar Pendulums for Moment of Inertia Measurements, SAWE PAPER No. 3237 Category Nos. 5 6

摘要

A common experimental problem in engineering is determining the mass moment of inertia (MOI) of a non-homogeneous rigid body with complicated geometry that does not lend itself to computational methods. This paper documents an attempt to conduct a comprehensive investigation designed to identify and eliminate the potential sources of error likely to occur when using filar pendulums to measure the moment of inertia (MOI) or rigid bodies. Trifilar pendulums were designed and built which obtained better than 1% accuracy. Testing with these pendulums is done with little to no fixturing, enabling high accuracy, low cost, quick turnarounds. These pendulums are designed for test objects with not-to-exceed weights and dimensions that do not produce significant windage effects. The techniques are explained in sufficient detail that others can construct an inexpensive MOI apparatus and effectively use it to produce quick MOI test results on a low budget.