1. Department of Mechanical & Aerospace Engineering

4. Topic AreaAerospace EngineeringMechanical Engineering Planar Trusses Engineering Statics Planar MechanismsEngineering Dynamics Planar FramesSolid Mechanics Planar Heat ConductionHeat Transfer Planar Mass-Spring- Damper Systems Vibrations Topic AreaComputer Science VarietyIntroduction to MATLAB

5. Department of Mechanical & Aerospace Engineering Will Morrow, Comp. Sci MS Candidate Sean Maguire, ME, MS Candidate Konner White, BS in ME, AE GUI Design & Assessment MATLAB GUI Software Development MATLAB Backend Code Weekly Meetings Students & Faculty Testing with Undergraduate/Graduate Volunteers

6. Department of Mechanical & Aerospace Engineering y x  k0  k  k --  k0 u = D – L D L i k Y X j P kA V kA M kA A B P k (X) V k (X) M k (X) Q kA Qk (x) Qk (x) j i

7. Department of Mechanical & Aerospace Engineering Main WindowEditor Window Main Window runs simulations and displays or exports results. Invokes the Editor Window. Editor Window creates, edits, opens, and saves designs

8. Department of Mechanical & Aerospace Engineering

9.  MATLAB Installed (2012b or higher)  URL: http://www.mae.ncsu.edu/academics/mae-course-websites.php At the bottom of the webpage click: Matlab App Double click on the file CADApp_Truss.mlappinstal l

10. Department of Mechanical & Aerospace Engineering Note: y E =16.32 mm (nonlinear)

11. Department of Mechanical & Aerospace Engineering Return to Editor Move a Node Using the Mouse Using Nodal Properties Table Change the Length of a Member Using the Mouse Node Deletion Using the Mouse Middle Button Importing and Exporting Schematic Files Using the Import from File Button and the Export to File Button

12. Department of Mechanical & Aerospace Engineering Eiffel said in 1887 (Le Temps (Paris), February 14): “Now to what phenomenon did I give primary concern in designing the Tower? It was wind resistance. Well then! I hold that the curvature of the monument's four outer edges, which is as mathematical calculation dictated it should be … will give a great impression of strength and beauty, for it will reveal to the eyes of the observer the boldness of the design as a whole.” As proof of the tower's effectiveness in wind resistance, it sways only 6–7 cm (2–3 in) in the wind. ____________ Named after the engineer Gustave Eiffel, whose company designed and built the tower. Erected in 1889 as the entrance arch to the 1889 World’s Fair The tallest building in Paris; most-visited paid monument in the world; 6.98 million people ascended it in 2011. The tower received its 250 millionth visitor in 2010. 324 meters (1,063 ft) tall, about the same height as an 81-story building. Has 3 levels for visitors, with restaurants on the 1 st and 2 nd. From ground level to the 1 st level is over 300 steps, same from the 1 st to the 2 nd. There are stairs to the 3 rd level but these are usually closed to the public and it is generally only accessible by lift.

13. Department of Mechanical & Aerospace Engineering 1 st platform 2 nd platform Top platform Challenge: Find the widths of the 1 st and 2 nd platforms subject to the constraint that the total width L 1 +L 2 = 339ft in order to minimize the lateral deflection at the top platform Hint: Begin the iterative design process with the baseline configuration in file JWEEiffel.schm.

14. Department of Mechanical & Aerospace Engineering Minimum deflection is 0.207 ft = 2.5 in at the top when L 1 ≈ 200 ft and L 2 ≈139 ft. Actual Eiffel tower dimensions are L 1 = 216 ft and L 2 = 123 ft. Given the simplicity of our 2D truss model, the insight than can be achieved is remarkable