Optimized Lightweight Aircraft Wing Design
Project Description
For my mechancial design and manufacturing course, my team and I were tasked with creating the lightest possible aircraft wing to meet a set of design criteria. These criteria were:
Must resist a load of at least 65lbs at the tip
Minimum surface area of 92 square inches
The design also needed to have a beam protruding 1 ½ inches (from the tip) with a ¼ inch hole at 23 inches from the base.
Each team then performed an extensive design, analysis, and manufacturing process. At the end, the wings were tested until failure and the teams were ranked on a combined score that maximized breaking strength and minimized overall weight.
In order to accomplish this task, we designed a wing with high yield and buckling resistance using 7075-T6 and 6061-T6 aluminum alloys, as well as high-strength aluminum foil. In the preliminary design stage, four different design candidates were produced and analyzed using PTC CREO, and a variety of software simulations and finite element analyses were performed. In the final design stage, we optimized the spar and bulkheads in addition to introducing an “axial bolt” design to anchor the spar to the base bulkhead. We then manufactured all necessary parts, primarily using a computer numerical control (CNC) mill and a waterjet cutter. When tested, it successfully held 155lb, with the spar ultimately failing at 195lb, giving it a load held to wing weight ratio of 167, making it both the strongest and lightest wing tested by wide margins.
Unique Approach
Our design was quite different than the other teams for several reasons. One reason was that we conducted real experiments to verify the simulation results. I convinced my team to manufacture several scale prototypes which we non-destructively and destructively tested. From there we discovered that the simulation results we were relying on drastically overestimated the strength of riveted connections. While other teams trusted the simulation results and relied on riveting an aluminum skin to the bulkheads to handle the tensile stresses and bending moments, I designed a system that used a thick axial bolt to connect the bulkheads and spars. This axial bolt allowed our design to create a much lighter design due to decreased reliance on rivets and thick aluminum sheet skin.
Skills Developed
This project allowed me to develop many technical skills such as:
Advanced CAD design
Generative design
Simulation of mechanical properties and loads
Finite Element Analysis
Advanced computer aided manufacturing (CAM) using CNC and waterjet cutter
Machine shop skills, such as using a Bridgeport Mill and a Lathe
Interested in learning more?
A detailed description of our design process, simulation methods, experiments, and results can be found in the Final Design Report