Hi, I am doing a science experiment. For that, I have made a small structure (sort of, almost pyramid like) using metal strips. I have calculated mathematically: its center of mass/gravity, moments of inertia matrix and principle MI axis ( usual formulae). My job first is to find these same parameters experimentally and then compare them with above results. What physical experimental methods are known to find C.M/C.G, MI and Principle MI axes? Did anyone try such stuff before? may be in lab, somewhere? please help!