Moment of Inertia Machine

• Christian Maya Ruiz
• Jawad Warraich
• Eduardo Ocampo
• Allan Gomez

Fermilab is currently establishing its first CubeSat project to search for potential dark matter decay product. In order to qualify for the space launch of their picosatellites, they needed certain testing equipment. Fermilab thus commissioned the building of a comprehensive, inexpensive and modular Moment of Inertia table. This team’s project is a machine that can measure the moment of inertia of an object about the X, Y, and Z axis. The machine measures the moment of inertia using torsion induced oscillations as proven in previous patents and current products sold on the market. Oscillations are produced by giving the CubeSat staging plate a small angular deflection. A highly elastic tungsten rod that is held tight by a clamping hub and a specifically machined shaft is also deflected. Because of its elastic properties, the tungsten wire returns to its original position. These oscillations are made possible with the friction reducing help of four Hudson ball bearings and a taper roller wheel bearing. The most distinguishable quality of this product is the compact size and user-friendliness. Not only is this machine thousands of dollars less than other machines on the market, but it is also just as accurate, within 5% accuracy. To determine the right materials for the machine, we ran Ansys simulations using a model designed in SolidWorks. The simulation tested the deflections on a machine made of aluminum and steel. The results were that the tables deformation would not affect the measurements. However, the tungsten wire proved to have a low safety factor, thus making it a consumable part, life cycle analysis was used to determine when it needed to be replaced. Simulink was also used to determine the uncertainty and vibration of the machine.