I have spent the past 11 days conducting experiments to ensure I choose the right materials and designs for the travois. Some of my experimental set-ups are quite big (See photo below)! I don’t have my own lab, of course, so I took over my parents’ garage. They have been very nice about keeping their cars outside for the duration of my experiments (which are not quite done).
No room in the garage now!
I have been testing the strength and elasticity of the different materials I might use in the travois frame. This testing has taken a lot more time and gotten a lot more complex than I had expected. I also had not expected that the total load on the frame would be more than the amount of weight placed in the cargo area. Welcome to a lesson in horizontal forces! Now I understand how much strength it must take for gymnasts doing the Iron Cross. Wow!
I also have started testing the various 3M products that might go into the final design. My 3M Mentor, Dr. Patrick Hager, sent me a box filled with the 3M products I had requested -- resins, fiberglass cloth, various industrial tapes, and Dual Lock. 3M’s Dual Lock has astounding properties, such as incredible shear strength.
In between the experiments and working with the 3M products, I have been using an online Computer Assisted Design program to design various options for the collapsible joints at the bottom vertices of the frame. I would prefer a fabricated steel joint like the one I drew in the CAD image below, but it would be too expensive. So I’ve figured out a different approach that still uses metal but would be much simpler and still create a strong, reliable vertex.
I am continuing to design elements of the travois as I try to locate the materials I need.