For my senior project, I was a part of Oregon State's AIAA DBF team as an Aerodynamics and Structures Engineer. 

This year we were tasked with designing and manufacturing a UAV RC powered aircraft capable of carrying a payload and deploying a banner mid-flight, towing the banner and then releasing the banner in air such that it will not sustain any damages. 

My specific role was the design and manufacturing lead of the aircrafts fuselage. I had to ensure that the fuselage's structure was strong enough for our high expected loads. The design was also made to keep the integration of other subsystems, such as the wing, nosecone, empennage and landing gear, simple enough for easy repair/replacement. 

Through load and stress analysis, we decided that a full composite design would be the best option. Specifically, we decided on a fiberglass design. Through various simulations and previous experiences, we chose to do a 5 ply thickness with orientations of: 0/45/0/-45/0 degrees. The manufacturing process of the fuselage were as followed:

- Mold manufacturing from MDF boards on the CNC router. Molds were made in top and bottom half configurations of the fuselage

- Prep molds with Duratec and mold release agents

- Cut plys in various orientations

- Lay up into mold with excess material to form tabs for attachment

- Vacuum bag the molds and cure in oven

- Epoxy two half together and machine off the tabs. 

I was also able to create designs and help manufacture the wing. The first part to this was determining an airfoil, which was decided based off of cruise speed, expected weight and our wing's aspect ratio of 10. With these variables in mind, we decided on a SD7062 airfoil. Our wing design was a full carbon fiber 5ft spar with balsa wood ribs to create the airfoil shape. We places the spar at the aerodynamic center to absorb all of the aerodynamic loads as balsa is not a structural strong component. The wing would then be wrapped with mylar to create the skin of the wing. Our aircraft also had ailerons for added control. 

Through a stability analysis, our team decided to create a symmetrical airfoil empennage to increase in-flight stability. This was made from balsa and plywood ribs and also wrapped in mylar skin. 

Both the front and rear landing gears were made from carbon fiber twill weaves around 25 plys thick. 

I was able to gain more experience with 3D design and 2D documentation throughout this project. I got to experience some FEA techniques and other material load/stress testing. 

Some other info on our aircraft:

- 6S li-po batteries

- Single KDE brushless motor

- 3D printed nosecone

- 3D printed banner release mechanism

- Foam payload tray

- 5kg empty aircraft weight

- Cruise speed of 60-70mph

- Banner dimensions of 12ft X 2ft

- 16 passengers at 5 oz each for payload

Some aspects of the capstone class included:

- Identifying customer requirements and specifications

- CAD iterations with 2D drawings

- BOM and budget creation

-Technical Portfolios

- Presentation of designs and testing results to our peers. 

Overall this was a great experience with plenty of challenges. It helped me gain experience with the design process, composite materials and manufacturing, various manufacturing techniques, presentation techniques, and team collaboration skills. 

I have included images of our prototypes and the final product, CAD drawing packages and my subteam's technical portfolio.