Lightweight bracket (v2)

For the optimization of this bracket I applied the concept of lightening above all the masses while maintaining the maximum size of the original footprint to preserve high moments of inertia. The result is a hollow shape that applies the same concept of the construction of aircraft that are large empty shells. I then stiffened hot spots with appropriate reinforcements. To properly assess the thin thickness (average 2 mm, 0.079 inch) I pushed the limit of mesh up to 1.2 mm (0.047 inch) Points constrained: annular zone Interfaces 2-4-5 results: - Weight: 424 g, (0,93 Lbs) 79.3% reduction compared to the original 2051 gr (4,52 Lbs) Stress detected with MSC Nastran solver - Vertical load: 754 Mpa 109,3 Ksi - Horizontal load: 694 Mpa 100,6 Ksi - Load at 42 degrees: 688 Mpa 99,7 Ksi - Torque: 400 Mpa 58,01 Ksi In order to decrease the weight I had to make the holes, after FEA verifying that major efforts have occurred right on the edge of these holes. Efforts are under the allowable value, however, can affect the fatigue life. A phenomenon similar to what happened with the first commercial jet aircraft some of which fell due to cracks that occurs on the corners of the windows. Adding reinforcements to the holes with a small weight gain, the reliability would be increased. Unfortunately the rules of the challenge geared towards maximum lightness. It would be desirable to evaluate a second version, perhaps in phase two, aimed at long-term reliability.