Friday, February 18, 2022

FIRST Robotics - Home Stretch

Monday

On Saturday we discovered that the center of gravity of the robot was too far back.  This gave us a disastrous 9 degree forward tilt.  The robot was in danger of sliding off the first bar.  The nose was 5 inches down and that made grabbing the next bar nearly impossible.  Solution time:


This new "C-grabber" means we put the balance point three inches further forward.  And the result?


Looks better.  Note the front of the elevator is on now.  Aluminum hoop below with polycarbonate sleeve above.  Oh, lets do a bit of actual engineering.


The hang now reads about 4 degrees nose up, and we can get it to +6 with ballast.  This should suffice to bring the second hang within reach - but still far from easy.  And the team found ways to make this happen without major frame surgery.

Other things happened on Monday as well.  The intake paddles need work, but mostly we need the competition robot to get everything connected so we can do dynamic testing as opposed to static.  It is not great when both hardware and software are running behind, but at least one side is not waiting on the other!

Tuesday

Robot Surgery.  Well sometimes you have to move a bracket even after all the delicate electronics are on board.  Since aluminum shavings are Death to Electronics some elaborate measures are called for.  Just as in real surgery.  Multiple layers of protective drapes.  Suction, here in the form of a shop vac.  the surgery was a success.  We'll have to do it again on Thursday when instead of drilling out rivets we'll be drilling holes for new ones.

Still experimenting with intake paddles.  We have the robot driving now, and these are much more effective in dynamic testing than static.  These simple polycarb strips are cut up parts of old robots.  I expect we'll tweak the design a bit before we expend new material.  It will take good driving to use this system.


Down on the software side of the team a bulletin board with cryptic messages.  Some relate to intake flippers.  Some relate to love.


Wednesday/Thursday

There was a special wiring and coding session on Wednesday.  I stopped by to mooch some pizza but mostly stayed out of the way.  Systems became operational one after another, albeit still with very vulnerable wiring and tubing all over the place.

Thursday was busy on a level that kept me from taking a single picture.  We did get through most of my Get it Done List but a good part of the team is wearing out.  

It looks as if we will get most things running in time, but how well?  One critical component seemed wobbly.  I was not quite sure why.  Turns out the kids making these were using the wrong size bolts.  "Why did you use those?" I asked.  "We couldn't find the right size", they said.  "Oh, sez I, you mean these here?"   

They need to switch from slop it together over to make it precise, tight and worthy of admiration.  We are not there yet.  I'm not sure we'll get there this season.


No comments: