RC Airplane
Design and Build for Mechanical Engineering Capstone
The plane in action can be seen in the video on the left where it was followed by a POV drone. The plane remains a part of the Victoria RC Modelers Society where it is used as a trainer plane for new members.
The team designed the plane to be a stable, trainer plane that was created from laser cut balsa and birch. After specifying the stall speed, motor requirements, chord and COG, the team began designing each component in Solidworks. 416 components and many sub-assemblies later, our model was complete.
Our completed Solidworks model can be seen here. This model was a team effort where each member focused on a section of the plane. I was focused on the fuselage and connection point of the wing. The plane would be build in two components, and the wing box was created to have a safe connection point between the two pieces.
The next step was to turn each of these components into a .dxf file so that they could be sent to the laser cutter. The majority of the plane was cut from 1/8 balsa wood because we were under weight constraints; however the fuselage, wing box, and some ailerons were made from birch to ensure the structural stability of the plane.
An example of the .dxf file is shown here. The different colours were used to mark the directions that the kerf was applied to each piece. External edges were increased by 0.05mm (shown in blue) and internal edges were decreased by 0.05 (shown in red), although in some instances these would be changed slightly to ensure press fit components fit snuggly together. After each .dxf was created, it was sent to the lab to be laser cut before being picked up and assembly was set to begin!
Assembly then began to take place, with the total length of the fuselage reaching 5.5ft and the wingspan reaching 6ft. Lots of super glue, sanding and trips back to the lab to pickup new modified components were taken at this stage.
Finishing touches now, adding the final pieces before covering the plane in heat-shrinking plastic. One piece was adding carbon fibre strips across the bottoms of the wing box to give the wings extra strength in this direction.
Adding the plastic was a finnicky step and required all 5 teammates support to apply proper tension and make sure no bubbles would form. First, we would iron along the edges of the wood then apply the heat gun to shrink the plastic and add in the tension to help keep the plane rigid.
Finally, the plane was complete and ready for a test flight. We had our pilot and mentor for the project Stewart complete the inaugural flight as we spent more time planning and building the plane then in the simulator. Seeing the plane take off was a fantastic feeling or pride and relief!