A new inverted pendulum to determine anelastic behavior of metals: Design and characterization

An inverted pendulum with a copper-beryllium (Cu-Be) flexure element was designed and its performance was determined by detecting the respective angular changes of the pendulum using a CCD (charge-coupled device) camera within an oscillation period range of 2-30 s. An arrangement was made by clamping the flexure element and pendulum rod to avoid subjecting them to compression stress due to the weight of the overall pendulum mass on the flexure. This form of inverted pendulum employs a flexure specially clamped to the pendulum rod to provide tension deformation under the weight of the mass and could be used for dynamic testing of highly sensitive flexure elements. The quality factors of the pendulum were determined with respect to flexure elements by measuring free oscillations decaying exponentially. The results showed that the inverted pendulum with a different connection between the flexure element, and pendulum rod can be used to measure the anelasticity of materials and to test elements under bending deformation in a dynamic way.