Rigid and Tension Bracing Set

Use the pins and shorter rods (and the washers to help with vertical spacing) to make a square grid. Because of the pin joints, the structure is not rigid. The longer rods can be used to brace some of the squares. How many bracing rods do you need, and where should they be placed so that the structure is rigid?

Next, use string or wire to make diagonal tension cables. These can bend but not stretch. How many of these do you need, and where do you place them so the structure is rigid?

See https://en.wikipedia.org/wiki/Grid_bracing for more information

These objects go with the blog post I wrote for The Great Internet Math-Off 2024. https://aperiodical.com/2024/07/the-big-internet-math-off-2024-round-1-match-8/