Mistakes of 2013
 

This thread is about the mistakes made by teams in the last year, not by FIRST. What I mean is what mistakes have teams made during the off season, build season, or during competitions, and what have you taken away from them. As we go through the different challenges that FIRST presents us with, we all grow and acquire new skills that we didn't have before. So what are some of the mistakes that you've learned from this year?

Re: Mistakes of 2013
 

Never... and I mean _never_... attempt a Helix lift for Frisbees.

"Helix" is a banned word these days on 3481... like Voldemort.

LOL

--Michael Blake

Re: Mistakes of 2013
 

Over complicating a climbing mechanism. The K.I.S.S. method is your best friend. :)

Re: Mistakes of 2013
 

Right after the kick off in our game analysis and strategy meetings we talked about full court shooting and came to the conclusion that accuracy at that distance would make it a bad design choice. It would not be a factor in the game. A few weeks later some video came out that totally proved us wrong. FCS indeed were a factor this year. Lesson learned, First teams will find a way. Don't discount strategies.

Re: Mistakes of 2013
 

Our team did make one mistake and that was going to one regional event with the event being a week six, this was very tough because by that time most teams already had one regional under them and made improvements for this one, we went into the event not knowing exactly what to expect

Re: Mistakes of 2013
 

We massively underestimated the abilities of other teams. We thought that if we could consistently climb to the 30-point level, we'd be one of the highest scoring teams at a regional.
Boy were we wrong.

Re: Mistakes of 2013
 

We bit off more than we could chew, design-wise.

(We still ended up with the best robot 1551 has ever built, but it would have been even better had we finished it early and had more practice time.)

Re: Mistakes of 2013
 

Our prototype to CAD to final production communications. We had a decent working belt shooter this year, but the some "improvements" were made in the CAD and it completely changed the shooter and we had to start over with 2 days left of build...

Re: Mistakes of 2013
 

1. Deciding to make a 30 point climber with a very limited budget. We ended up scrapping the whole design at regionals in favor of a 10 point climber, but our robot was at that point pretty much useless for defense due to all the weight cuts we made in order to try to get it to climb.

2. Casters: never again.

Re: Mistakes of 2013
 

Once again ignoring the rule that game piece control is critical to winning the game. We really needed an active floor pickup on our robot.

Re: Mistakes of 2013
 

Assuming that building a 30 point climber with 7 people was possible with only 11 hours of build time a week.

Re: Mistakes of 2013
 

Why?

Re: Mistakes of 2013
 

(My personal opinion) We should have spent more time dialing in our FCS better, instead of tuning other shots.

Re: Mistakes of 2013
 

As has been said, assuming we could do a 30 pt. climb with limited mentorship and few resources.

Assuming that a mid-field feeder bot was going to be utilized (it wasn't, we ended up playing defense most of our matches, without much pushing power, which didn't do well in the end.)

Accidentely leaving a safety block for our arm in during a match, trying to rotate that arm, then shearing all screws holding it on the sprocket that turns it.

Deciding not to put on an easy 10 point hang that we had with us at competition (I have no idea why...but it will be on for offseason events.)

Attending only 1 regional (We had most of our technical issues worked out by the end of it, but it was too late by then.)

On the back of the one above, not fundraising enough to attend two regionals. (We did do some fundraising, just not $5000 more than what we have had in previous years. We have only ever attended 1 regional a year.)

Going with a tank style driver set-up when we decided to have a kiwi drive (we slipped a whole lot, and it was hard for the driver to control, resulting in too many tech fouls.)

Using too many parenthesis when I write (I mean seriously, who does this? :rolleyes: )

Re: Mistakes of 2013
 

Game piece control is important because that is usually the main way to score points. The easier and faster you can acquire game pieces usually translates into more points scored. Obviously a generalization, but one that holds true in most cases.

We needed an active floor pickup because our passive pickup was slow and unreliable. Also an active pickup opens the door to a 7 disk autonomous which was one of our stretch goals we did not achieve

Re: Mistakes of 2013
 

If you only pick up off the floor in autonomous, then you can get away with a 1986 spatula design. If picking up off the floor is your primary source of frisbees you need an active pickup like 2056, 254, etc.

Using a spatulatesg manipulator can be used in teleop however it is an extremely hard and inefficient way of collecting discs.

Whatever your primary source of collecting game pieces is it should be quick and guarantee control of the game piece. KISS is a good practice to follow but sometimes stupidly simple is too simple and too ineffective.

Re: Mistakes of 2013
 

I understand why active control is good. I wanted to know the particulars of why Sisk thought RoboKong needed active pickup.

Re: Mistakes of 2013
 

For 2495 we probably could have tried a wider intake mechanism that funnels at the top instead of a single width intake. It would resemble 1538/33's bots.

https://fbcdn-sphotos-e-a.akamaihd.n...94197621_n.jpg

versus

https://sphotos-a.xx.fbcdn.net/hphot...34357633_n.jpg

A custom spur gearbox probably would have been a good idea as well, but COTS did fine for what we needed.

Re: Mistakes of 2013
 

For our shoulder joint, attempting to go with a minimal reduction + counterbalance rather than reducing to the required design speed. Many of the issues we faced at our first district could have been solved with additional reduction to our shoulder joint (and were solved by implementing this at our second district). We had too many issues attempting to dial in the required power for our shoulder motor and our PID with the minimal reduction. Too low power to the motor meant too much stalling, and too high power meant too quick of motion for the PID to execute properly. And the non-constant force of surgical tubing as the counterbalance also presented significant issues. We rectified this by adding a second stage of reduction before our second district, and virtually all of these issues were solved.

Re: Mistakes of 2013
 

Making strategy and design decisions before prototyping. One shouldn't assume shooting is hard, or that it's harder from some distances than others, without a shaky prototype or two under your belt. If we took some wheels and motors and built a rudimentary shooter in Week 1, we'd have known that much earlier that shooting isn't impossible.

I wish we had abandoned climbing a week earlier. If we had three more days in the shop we could have averaged 36+ ppm at BAE.

Re: Mistakes of 2013
 

1) Our ground speed (10 fps with a non-shifting gearbox) was too slow. We had more control than we needed for alignment, and not enough speed to get around defense. Pushing wasn't as important as we expected.

2) Cable drive (climber) without "keepers" to prevent cables from coming off the pulleys when tension was lost.

On the other hand, we violated one of our normal rules and it proved NOT to be a mistake: We relied on gravity rather than active control to move, stack, and index the game pieces in the robot.

Re: Mistakes of 2013
 

Don't assume that the challenge is harder than it is, and skip over "it can't be that straightforward, can it?" solutions.

Don't do things that you don't have the money to do.

Don't assume that when you get the manufacturing resources of "powerhouses" that you will then have an easy build season, if anything it was more demanding than ever.

When a little voice in your head tells you "there's too much stuff in this robot" around week 2, listen to it.

And a personal one, don't say "yes" to as many things as I did when you're going to be busier during build than you've ever been in your life.

Re: Mistakes of 2013
 

Recruit and train early. New members are much more likely to be functional during build season if they already have experience with team activities.

Re: Mistakes of 2013
 

We have words like that on 2614, including "Mecanuum" and "scissor lift."

Re: Mistakes of 2013
 

One mistake of our team was us mentors getting burned out trying to figure out a floor pickup system instead of investing those hours improving our loading and shooter on a perfectly capable cycling machine. If we had spent those hours we burned away on a floor pickup on improving our loader and shooter, we likely would have walked away with a blue banner or two this season.

Re: Mistakes of 2013
 

Deciding to do all the aspects of the game. We underestimated the importance of an extremely accurate shooter and instead spent lots of time on a 30 point climber that sometimes, at its best, went to 10. Here's a link to our robot's info page : http://www.team708.org/current-robot.html By the way, at our most recent off season, Monty Madness, we took off the climber (after the event was over.) We hope to build a ten point climber by our next off season event MidKnight Mayhem.

Re: Mistakes of 2013
 

Trouble shooting inconsistancies in our shooting. Our floor pick up was awesome but we failed to correctly diagnose problems with our disc delivery "bucket" that lifted them into the shooter mechanism. The inconsistent lift of this device lead to inconsistent shooting and jamming in the later season. We thought we had it several times but it would return after a match or two of minimal problems.

The unlikely source, an intermitant pneumatic cylinder. We have used cylinders on all our robots since 2010 and never had problems but these were long stroke with a "dainty" rod diameter.

The good leason, aquire game pieces and shoot quickly. Shooting 70% of 16 discs is better than shooting 95% of 8 discs.

Re: Mistakes of 2013
 

Funny, I think that if we'd have spent the hours developing a floor pickup system instead of a 30-point climber, we'd have walked away with one or two blue banners this year. :)

Re: Mistakes of 2013
 

Not having a solution for upside down Frisbees in your hopper before you get to Champs. Of course we lose our first match by 2 points with an upside Frisbee in our hopper. Then at the end of the weekend you realize you missed out on a 8-0 record and #1 seed because of the dreaded upside down Frisbee in your first match. But you can't change the past so just keep moving forward.

Turns out 1 self-tapping screw was the solution.

Re: Mistakes of 2013
 

Our entire design process. "Let's split into groups and the best idea of the group wins! You have 5 minutes. Go!"

That and deciding on day 1 not to do a climber because we didn't have any ideas right off the bat.

Um...not making a CAD model of the robot before building it...again. :o

Re: Mistakes of 2013
 

Not designing the robot in CAD (we're working on making that better for next year)

Spending 3.5 weeks prototyping and sketching designs. - I was very busy with FTC for the first part of the build season, so I wasn't able to be around for a lot of those meetings, but I attended kickoff, and our post-kickoff brainstorm, and that went very well, but I came back over halfway through the build season, and we barely had a drivetrain! D:

Re: Mistakes of 2013
 

Building a key piece (our hopper) out of acrylic*, which has a tendency to shatter and break.
Yes the bright orange polycarb looked very, very pretty (especially when we cut 'FIRST Team 1912 Combustion' to it) but we took a hammer throw to the wrong place and crack a part, got into some defensive pushes and broke off a piece, etc. Between our three competitions (Bayou, Razorback, CMP) we had four hoppers. Wedneday night of Razorback we were using hotel dollys to bring tool boxes up to one of the rooms to do maintenance. One of the favorite sayings of the pit crew and drive team / one of the most hated sayings by the pit crew and drive team was "Guys, lets change the hopper!" This did however, have a silver lining that JVN would appreciate: it forced us to iterate and therefore, with each event, our hopper improved. On our team, we had never really been able to do that; to test a piece in competition, notice that there could be improvements (like making the feeder slot larger so the human player can feed faster) and making those changes. I think that process helped our students learn to analyze machine features.

Re: Mistakes of 2013
 

Do you have a link to a picture of said hopper? Sounds like acrylic to me...

Re: Mistakes of 2013
 

It is acrylic, my bad. (oy vey, I mix it up every time. To quote Annie Hall "Always the wrong answer").

Picture (with v1) - http://team1912.com/photos/slideshow/hammerhead.png

What it looked like at CMP - https://www.facebook.com/photo.php?f...type=3&theater

Us working on it in the hotel room - https://www.facebook.com/photo.php?f...type=3&theater

Re: Mistakes of 2013
 

Step 1: Don't use acrylic for that application
Step 2: See Step 1

:]

Re: Mistakes of 2013
 

I think I posted this in the things you only do once thread, but, it more classifies as a mistake.

We spent our whole season making a scoop (like 1986's scoop, but way worse), that didn't even work at Waterford, our first competition.

This is what it looked like (it would just fall down during the match, unable to come back up): http://www.flickr.com/photos/daniele...57632965760216

Needless to say, we stripped the robot of it afterwards, improved our feeder intake, and we were pretty successful.

Re: Mistakes of 2013
 

I think deciding to go with Mechnum's cost us getting picked @ champs.
We had the 15th highest OPR in our division and nobody wanted us.

Re: Mistakes of 2013
 

Or it might have more to do with the fact that OPR is not an accurate measure of individual robot performance. How much did you actually score per match and how did it compare to the rest of your division?

Re: Mistakes of 2013
 

What did your hopper look like? Our team found a creative way to solve that problem, although we never had to deal with it at comps...

Re: Mistakes of 2013
 

Not true Ed, there were too many pure cyclers on our field. Our second pick had mecanum but could cycle, full court shoot and block up to 80". Versatility was why they were picked.

Re: Mistakes of 2013
 

I just want to point out that working on your robot outside of the competition time is illegal. Here is the rule:

Re: Mistakes of 2013
 

I'd imagine it would be ruled as a part of the 30lb witholding allowance

Re: Mistakes of 2013
 

They worked on the hopper between competitions and on a Wednesday night in the hotel. If it was part of their withholding allowance it is perfectly legal.

Re: Mistakes of 2013
 

It was part of our 30lbs allowance. (It was much, much less than 30 lbs though, and the only robot part we did bring in). IndySam and mman1506 correctly guessed that, but I wanted to confirm.

And rule-enforcing-good-guy-Gregor beat you to the punch, he double checked with me this very same question about a week and a half ago.

Re: Mistakes of 2013
 

Not everyone on the team will agree with this, but I would say our biggest mistake was focusing too much on full court shooting. It over constrained the design of our robot since the feeder tray had to be on the back of the robot, and the shooter at the front. This left too little space for other mechanisms (climber, floor pickup). We spent so much time tweaking and perfecting our full court shot, and never really used it in competition. If I had to do it again, I would put the feeder tray above the shooter at the front of the robot, and put a nice floor pickup in the back.

Re: Mistakes of 2013
 

We decided against a floor pickup and our post-championship analysis is that this decision was okay.

What we did was:

Score a solid 18 points in autonomous;
Run ~4 cycles to the feed station and score well in the 3-point goal with these Frisbees;
Play effective, active defense as needed;
Run around most defenders; and
Climb for 30 points in late-season matches

This year's game was great in that no team could realistically do everything well. A well-selected alliance, however, could. There were certain suites of capabilities which were in demand (a FCS; a floor pick-up robot capable of a 42-point autonomous; an FCS blocker; climber;...) but this year, it was the best alliance which won, not the best robot.

Ultimate Ascent was the best FRC game to date, IMHO.