I skipped last Friday's post on robots. It was effectively Make or Break week. The phrase does not quite fit. It's actually quite positive when you make something, test it to breakage and remake it better. But as a time period when things Must Happen for the project to succeed, well last week was it.
Collectively the Monday, Tuesday and Thursday sessions were OK. Things got made. Nothing got broken. By late Thursday the robot in its final form could be seen. Of course the second set of pneumatics is just loosely positioned and the electronics board is not on. But basically this is it. The team has named it HANK.
That little dial on the top. Lets take a closer look.
This measures how far off level the robot is when it hangs. We initially anticipated a "nose up" reading of perhaps plus 3 degrees. Turns out it is nose down at minus 4 or so. That meant the robot actually started to slide off its initial hang just a little, hence the small wedge. Our CAD guru says we can pull this off IF we get the angle to a slightly nose down minus 2 degrees. Here's my idea of high level engineering, and what I think will be the defining picture of the 2022 build season:
Get the robot onto the first bar. Stack water bottles on the back bumper. That tells us how much weight we need to bolt on back there. About 7 pounds of "something" should do it. I have not been without error in this build season but my fanaticism in pursuit of weight management will now give us this option.
We are still struggling with the geometry of our second climb. The total weight of the robot is still fine but its center of gravity keeps shifting. When we put it on the hang bar today and saw it read 9 degrees nose down I almost despaired. How can it keep doing this? Well we knew this would be the last system finished and think we might have one more trick up our sleeves. So the jury is still out on this project.
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