So we did a bunch of work today and got to drive the robot around a bit. Turns out the window motor overheats pretty quickly running the arm. We are currently using bungie cords, but we might have to use surgical tubing or something else instead. Yesterday we found the big sprocket on the arm was getting pulled out of alignment as it turned the arm. So today we added brackets to keep that from happening. the problem is the arm ballooned out to 28 pounds. We did some major cutting on the brackets and got it down to 26. The brackets are made from 1/4 inch thick aluminum. (all we had left) We will be ordering some 1/8 inch thick aluminum to replace them with.
http://www.youtube.com/watch?v=T-8KXDW74Oc
We also improved the rigidity of the arm mount. The slide mechanism still needs work. We will have to figure out a way to make the wire guides work better, and will probably need to make a roller system that keeps the wires where we want them.
either that or we will come up with something else. I must say I am glad we kept up the schedule we did this year giving us time to beef up the places we need to. We did end up 1 pound over weight. So spent some time cutting things back. The hard part is that that gives us very little room to grow.
This is probably the best shot of what we did to our brackets. It keeps the sprockets lined up nicely, but means we have to redo our safety shield out of cardstock or something. :-)
Right now it is a chopped of arm waiting to happen.
Finally we got started on our cart. After seeing this video we got an idea.
http://www.youtube.com/watch?v=PScY_--XAM4
We came up with this.
There will be two turn tables mounted on each tower, and the robot will sit on a tray mounted between them. We hope that we will be able to tilt the robot on its side while working on it so that we can get to things like wheels and electronics without having to move too much around.
So maybe I will regret signing us up to show off our robot at the bellingham museum of radio and electricity next Saturday...the last Saturday of build season.
What was I thinking!?
Edoga