pic: Wooden Thunder, Team 1294

[Rick TYler]

Originally Posted by CrazyBear

Wow, nice craftsmanship. Did you guys experiment with different types of wood such as Mohagany or Red Wood before settling on a couple of specific types of wood for the overall robot design? Was there another reason for choosing wood for the robot design besides not having a machine shop readily available?

First off, I might want to be your team when I grow up...

We didn't experiment because I already knew what we should use, and what we could afford. I've been a hobbyist furniture and cabinet maker for 15 years, and an amateur boat-builder for three. I already know the characteristics of different materials.

We used fir for the rail-protectors (don't want to call them bumpers) because it is strong, but resiliant. We want the wood to give a little in this spot or else we might have used oak, maple, or jarrah. All would have more impact resistance than fir, but they are much heavier and won't absorb as much of the impact energy. The front and rear are 13/16" red oak because I had some scraps laying around, and we were a little too long to use the 1-1/4 fir I had.

The tower is made from boat-building leftovers. I had a nice half-sheet of 1/2-inch marine-grade meranti. Again, in a perfect world I would have used 12mm okume for this (lighter), but that stuff costs $100 a sheet.

The tetra-grabber platform is fir construction plywood because that's what the arm team grabbed for the job. I would have used the okume -- or 12mm baltic birch -- but they wouldn't wait for me to get to the lumberyard to get some. Besides (recurring refrain) we already had the construction plywood on hand...

Our chassis is the KOP aluminum channel, and we used some steel tubing for arm components and the tower braces. The tetra grabbers are custom-fabricated steel and are our only welded pieces. The shaft for the arm is a steel tube captured in a pretty heavyweight piece of rectangular aluminum.

I think it's a nice blend of materials, and a great example of a decent robot built cheap. We think it will be a top-10 'bot at our regional.

Thanks everyone for the kind comments. I'll pass them along to the students. They built it.