Nightmare Repairs At Competition

[Lil' Lavery]

Originally Posted by Kyle A

My junior year on the team, 2006 Ramp Riot, The robot we shipped in the crate was far from perfect.

The name of the 2006 game was Aim High. Ramp Riot is an off-season event held by team 341 each November.

[thefro526]

I'm not sure if this was a nightmare repair, but it is a good story.

In 2010, as a mentor and coach for 816, I had the pleasure of watching our robot go up in smoke during autonomous mode in one of our qualification matches. Initially, the autonomous looked routine, the robot began to move forward slowly as it always did and then drifted to it's right. Initially, it seemed like a routine 'the robot is being dumb again' moment... And then it started smoking.

I frantically hit the E-Stop and ran out of the box to the side of the field to see Pete K (FTA at the time) on the opposite side of the field with a fire extinguisher. I think I shouted something like 'No, wait!' to him, and once the match had been paused/canceled (or before by some accounts) I got on the field and opened the robot's lid to air the smoke out and found no fire.

Thankfully, since the match had been stopped, we had to wait the minimum 6 minutes to reset the field. Everyone assumed that we would take the robot back to the pits to fix whatever was wrong with it, but we found the problem fairly quickly right there on the field. Turns out one of the PWM cables going to the right side of the drivetrain shorted out and burned up most of it's insulation. Some time after we found this, our 'pitmaster' was standing on the side of the field asking what we needed to fix the robot, at which point I shouted 'PWM Cables' at him. Something like 2 minutes later he came back with a ball of PWM Cables and we rigged the robot up to run without ever leaving the field... And we won the match too. Good Times.

http://www.chiefdelphi.com/forums/at...8&d=1270046943

[EricVanWyk]

Originally Posted by Koko Ed

I'd say 1592 and 801's beats everybody's story for all time.

I haven't been able to get my chiefdelphi fix since Tuesday and I'm jonesing... can you spare me a link to this story?

[George1902]

Originally Posted by EricVanWyk

I haven't been able to get my chiefdelphi fix since Tuesday and I'm jonesing... can you spare me a link to this story?

http://www.theroboshow.net/

It's the first story in Episode 2.

[EricVanWyk]

Originally Posted by George1902

http://www.theroboshow.net/

It's the first story in Episode 2.

Thanks!

[Lil' Lavery]

Originally Posted by coalhot

I remember this, walking around the pits in Philly 2008 and seeing the arm split in half. If I recall, you guys got it completely replaced with the spare in time to have a fully functional robot in the first quarterfinals match. It was quite impressive.

We didn't hurdle in the first quarter-final match, as we weren't confident in our repair yet. We did participate in the match, run laps, and lock an opposing track ball in the corner for as long as possible. We managed to get a bit of testing between QF1-1 and QF1-2, and were back in full force in the second quarterfinal. Not that it mattered much against the 103+272+834 combo. They summarily trounced us.

[coalhot]

Originally Posted by Lil' Lavery

Not that it mattered much against the 103+272+834 combo. They summarily trounced us.

This. One of the best finals in Philly I have seen, since 2008.

I remember MOE doing some last second repairs at Philly in 2010. Not sure If they were nightmare-ish repairs though.

Also, can we forget 75 at MAR and (I think) BE? The robot split in half, and they still fixed it.

[Lil' Lavery]

Originally Posted by coalhot

Also, can we forget 75 at MAR and (I think) BE? The robot split in half, and they still fixed it.

Ramp Riot. Pretty sure they didn't play in either event after breaking their turret off. Not because they couldn't fix it, but because their alliances were eliminated in both of the matches the failures occured in. Somehow I doubt they would have continued playing even if their alliances had remained in it, though.

[Koko Ed]

One of the most memorable ones I witnessed was the last Canada's Wonderland event where 1114's robot unleashed a mushroom cloud in the finals. It was like time stopped right then and there.

[pmangels17]

At Duel on the Delaware (Fantastic Off-Season hosted by 365), we were #1 seed. We selected 341 as our first pick, and 1640 as our second. Then, in the semifinals, the giant lazy susan bearing we used on our turret snapped. The turret smashed onto the ground as we crossed the bump on the field. However, with the help of our great partners, and a six minute tme-out, we managed to get enough zip ties (approximately 40 normal size and 10 ludicrously large) onto the turret to hold it in place. It didn't spin for the rest of the day, but it worked in auton and for scoring, and we wound up winning.

Moral of the story: If you don't carry about 300 14 inch zip ties, you might not be prepared for your next inevitable breakdown.
Side note: 14 inch zip ties can be used for a number of things, including wiring organization, air tank mounting, turret repair, and mounting/securing almost any part on your robot.

[AlexH]

Originally Posted by pmangels17

At Duel on the Delaware (Fantastic Off-Season hosted by 365), we were #1 seed. We selected 341 as our first pick, and 1640 as our second. Then, in the semifinals, the giant lazy susan bearing we used on our turret snapped. The turret smashed onto the ground as we crossed the bump on the field. However, with the help of our great partners, and a six minute tme-out, we managed to get enough zip ties (approximately 40 normal size and 10 ludicrously large) onto the turret to hold it in place. It didn't spin for the rest of the day, but it worked in auton and for scoring, and we wound up winning.

Moral of the story: If you don't carry about 300 14 inch zip ties, you might not be prepared for your next inevitable breakdown.
Side note: 14 inch zip ties can be used for a number of things, including wiring organization, air tank mounting, turret repair, and mounting/securing almost any part on your robot.

[Peter Matteson]

In 2010 at the championship in our second to last match on Friday we fell off the bar when our climbing cable crimp failed.

We had to rebuild half our articulating drivetrain in 70 minutes between matches to get back out for the last match of the day. We knew we needed to prove to everyone our robot was functional before pick lists were made that evening. We had most of the inspectors in the division and a couple of nearby teams watching the whole ordeal because they couldn't believe that we had planned for this, had the parts ready and actually pulled it off.

Our plan worked we were back together and played our last match. The event effect divisional picking in our favor allowing this to happen...
http://www.chiefdelphi.com/media/photos/35698

I have never been prouder of our students than that day because of how they handled this situation. Our mechanical team in the pits knew what they had to do and did it no griping no issues, just get it done as fast as we can.

[KrazyCarl92]

In 2011 our team used a crab drive from 221 robotic systems for our drive train. It was set up with a window motor steering all 4 modules together, but the window motor was overheating frequently at both of our regional competitions. This led to the thermal switch in the window motor tripping and our modules would stop steering as a result. At Connecticut we ended up switching out one of our modules for a spare, thinking that perhaps the axial shaft of the module was too "beaten up" (it appeared fairly marred as compared to what we expected). This turned out to be the wrong explanation, but we left the module in anyway since nothing had changed for better or worse.

Upon returning back home, we noticed a thin ring of metal that appeared shaven on the bottom plate of the swerve module. We then reasoned that the likely reason for the window motor issues was this rubbing between the bottom plate of the swerve modules and the bottom of the frame. We came up with a plan for how to deal with the issue if this was in fact the problem at Championship, since not being able to drive would be the worst thing that could happen. We gathered thrust bearings and material for spacers to be machined once we arrived if we found this was the issue.

On Wednesday night at Championships, we send in our five people: me, our pit mentor, our driver, a programmer, and the programming mentor. We used a piece of paper to see if the pieces of metal that we suspected to be rubbing were. 3 out of the 4 modules had the issue, so we had to add thrust bearings in the axle shafts, get the bronze bushings that the snap rings sat on turned down, and have several delrin spacers machined to the proper height. In 3 hours we ripped apart the entire drive train, got the machine shop to precision machine 20 parts for us, put the drive train back together, then ran some systems test. The drive train worked beautifully for the rest of the competition, and had our autonomous worked or a button on our controller (of course the all important minibot deployment button) not failed, we may have been selected for eliminations.

The best part was returning to the hotel and reporting back to the team what we had accomplished. One of the kids said completely seriously, "You mean you ONLY got the drive train fixed!?!?"

[Karibou]

West Michigan District 2011, we destroyed our drivetrain.

One of the bolts in the drivetrain came loose during a match, and the wheels on that side stopped turning. The drivers kept driving on it because they had no way of knowing if it was an electrical, code, or mechanical problem. I didn't see the match because I was cleaning the pit, but when they brought the robot back after the match, I nearly cried.



Unfortunately, this is the best picture I have. You can't see the full extent of the damage, which is several chunks/teeth missing. I think there was some damage to the chain and maybe the axle it was on, but I don't remember - I wish that in our state of panic, we would have thought to get a picture. It was bad. That sprocket was on the center axle and was welded to a hub with another sprocket to form a sandwich. We sent the sandwich and a new sprocket with a mentor allllll the way to the machine shop on the other side of campus to be welded and worked on cleaning all the metal shavings out of the robot and fixing other problems (it turns out that 24V valves in your pneumatics won't work too well) while waiting for it to come back.

Mentor comes back with the destroyed sprocket (IIRC it wasn't bent that badly before sending it there, that was just a result of getting it off of the sandwich) and the new sandwich...which was still not usable. Apparently the welding machine jumped and the result was a tooth that was completely missing and some other tooth deformation. Sent it back to see if anything else could be done, and asked frantically through the pits to see if anyone else had a spare sprocket that we could have. We found one, and decided to drill some holes in our only spare hub and bolt everything together. Ten minutes of ratcheting and two sore wrists later, we had a sandwich that was usable.

It was by no means the best fix, but we had already missed several matches and our next one was in a few minutes. We made it out to the field literally just in time to play for our last match of the day.

-----
Not a nightmare repair at the competition, but definitely a pain in the everything:
http://www.chiefdelphi.com/media/photos/35270
See that bent corner? Having to attempt to straighten it after every match that we moved in was the bane of my existence that year. That robot was all about poor design choices, and the frame was one of them.

[Madison]

This is a picture in the middle of the repair. The 'before' -- which I don't have a picture of, unfortunately -- was pretty terrible.

We collided with 360 at full-speed midfield. Our frame, which wasn't designed to play the kind of defense we ended up playing in Portland because of a too-complicated collection system, completely collapsed. The front cross member bent inward as far as the intake roller and split in half at one of its rivet holes. The left-side frame rails collapsed as well. There are ripples in the flanges along the entire length of the left-side of the robot.

The rear-mounted gearbox and final gearing stage were knocked wildly out of alignment. The gear mesh distance was busted up and destroyed the teeth on the final gear attached to our wheel. None of the wheels remain planar with one another.

http://www.youtube.com/watch?v=r_OZi...ature=youtu.be at about 2:35.

We fixed it with a hammer and by riveting some aluminum angle along the front edge of the robot to keep everything square. The drive gearing remained mostly broken for the rest of the event; we were able to adjust it before each match so we could drive, but it'd go bad by the end.

We're replacing some of the frame parts at our event this weekend and replacing the gear stage with another chain and sprocket stage. We've also rebuilt our entire frisbee collection, storage and shooting system.