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[DFTF] The Classic Blunder...
This is part of a series of posts called Drinking From The Firehose on getting Dr Joe back up to speed on All Things FIRST.
![]() Today's topic: The Classic Blunder... No, I didn't get involved in a land war in Asia. Nor did I go against a Sicilian when Death was on the line. No, my blunder was even more classic: I designed a robot that SOME team could finish in less than 45 days, just not MY team. As the picture above implies, I have been trying to make up for it by working myself to death for the last 3+ weeks, thinking I could set things aright by din of effort. It has worked to some degree. Our chassis was looking awesome when I turned out the lights in The Box* this morning and headed to my day job. With more hard work between now and Tuesday Midnight, we will have a pretty amazing chassis, one that no rookie team has any business building: We'll cross the barrier with ease, we should be able to balance a Box of Rock on the Coopertition Bridge, we may even be able to help pull off a 3 robot balance after lunch on Saturday. It has other features as well that I won't go into (hint: we've named it, The Rook)... ...this sounds like a list of positives, but actually it works equally well as a list of negatives. You see... ... I am out of gas, we're almost out of time, and we've got nothing to handle balls... ...at all. We've got weight for it. We've got space for it. We even have a reasonable concept or two we've sketched on various napkins over the last few weeks. What we don't have is TIME. I can hear myself saying the words to my Rookies: "It doesn't matter what Cheesy Poofs can build in 45 days, or Thunder Chickens, or Swamp Thing, or Miss Daisy, or WildStang, or CHAOS, or Beatty, or Buzz, or Pink, or ANYONE ELSE can build in 45 days...I said it. I believed it. I meant it. I just didn't do it... and there are only 106 hours left... Joe J. * Where else would you expect a team named Schrodinger's Cat to work? |
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Don't forget about that 30lbs withholding allowance. Try building a way to mount your ball handling mechanism in the time from now until stop build day. then, while waiting for competition, try to figure out how you're going to score. If it has to be a stationary dumper that requires you to be a fender scoring bot, then that's not a bad thing. just make sure you can get balls to place on your robot where an end effector can be used, and build it before you bag the robot. It sounds tough and it definitely will be, but what else do you have to lose?
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Always remember, that 30 pounds withholding is huge. In 2009, we withheld our entire turret. In 2010, our lift system. In 2011, our minibot deployment system.
This year, I think we may get lucky and be able to bag an entire robot (for the first time since 2008). Use that withholding allowance to your advantage. |
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With the materials you have on hand, how hard would it be to create a minimalistic ball acquisition and storage system (a la 1902 in 2006)? |
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What makes you think we're finished building? We have a proto that moved onto the bridge last night. We think we see a light at the end of the tunnel but it could be that fatigue is putting up spots before our eyes. I will know more by tomorrow night I hope! The reality here is you can prototype between stop build and your regional. Plan on what you can bring to manufacture and work like crazy on the practice day. I bet everyone of those teams you mentioned has taken their robot apart on the the practice day at least once having figured out that some parts won't work the way the game is played or the functionality is not needed due to a different strategy. |
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Fellow Rookie,
We just got our powder coated parts back from the paint shop today, and we have all weekend to build. We do have a practice robot mostly finished, but we too have a bunch of work to do. Keep in mind that you can walk in to the event with 30 pounds of custom parts. Have a great weekend, Andy |
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This being my 12 year of FRC, I've noticed the competition change in little ways here and there, but the withholding allowance has been one of the most major changes in FRC these past 5 years. The days of crating your robot by Monday night, so that FedEx could pick it up at some point Tuesday morning - are gone. (I almost miss those days) Now we can (and many teams do) build 3/4 of a robot in 6 weeks and then spend another 3-4 weeks building/perfecting the other 1/4 (often some very important component).
So as others have already mentioned, use the 30 lb withholding to your advantage and I'll be at the door checking your weight (at least in spirit). PS: Everyone else - if you bring your bumpers into the competition unbagged, it counts towards your witholding allowance!! Other blunders to watch out for.... 1) Loose chain may work for a little while, but it will fall off at the worst possible time. Find ways to properly align and tension chain. 2) Loose electrical connections may work for a little while, but will work loose at the worst possible time. Find ways to secure, crimp, and attach wiring. 3) Fasteners like screws, bolts, and nuts MUST be locked down using locknuts, threadlock, lock washers, etc. This year with many fast spinning wheels to shoot balls, things will tend to work themselves loose! |
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Yeah, the 30lbs is HUGE! We added enough length to our arm to use the 3rd row in between regionals last year. Concentrate on the drive train and the gatherer, fix the shooter and bring it to the regional. You'll sacrifice most of Thursday but it is better than nothing.
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The withholding allowance is definitely a possibility for you to get some extra functionality on the robot. Just don't succumb to the follow-on to your Classic Blunder, building all practice day and missing inspection and practice. You know how important driving practice on a real field is, especially for your rookie drivers. You already made the mistake of designing a robot your rookies couldn't finish in 45 days. Don't double down and design and build a secondary system that your rookies can't install, wire, and program in 4-6 hours. I'd vote for a simple ball collection and transport system. Even better if you can work out your mount-points beforehand and get those installed on your chassis before you bag it.
PS. We've all been there. Sometimes even after you've been working with the same team for a decade. Just make a note to expand your capabilities in the off-season and retract your expectations slightly next year. |
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http://www.chiefdelphi.com/forums/sh...58&postcount=3
The OCCRA kids built this bot this past fall. It is a very simple collecing and scoring mechanism that had a high pivot and a set of balls that sucked up and spit them back out in goals up to 60 inches tall. It was a very effective scorer. Also, if your chassis is as described, it should be good for at least 10 points a match and maybe more. There is a fairly simple method to score 8 points every match as long as your robot is not too tall. 8+10 will win most matches, and I would almost garauntee a spot in elims (though probably not the finals). |
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The 30lb withholding allowance does not apply to unmodified COTS parts. This means that you can with hold in excess of 30lbs of your robot assuming that you only have 30lbs of fabricated/custom/modified COTS parts (Andy's had me thinking about this for a bit). Not sure what you're looking into withholding, but depending on how it's built and how much is COTS you could withhold darn near half your robot - or at least I know that we could. |
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Joe, your situation is not unique to being a rookie team. On 968 one year, we shipped nothing more than a completed base, which we had not even driven. In 2008, the year we made it to Enstein, we did not ship it to its first event with a working ball mechanism. In fact, we had the last parts of the ball mechanism shipped to the hotel in San Diego, where they arrived at 9:00 AM on Thursday morning. Talk about cutting it close. There's a lot that can be done very quickly if you have a solid plan and the dedication and tools to implement it.
Currently, in 696's 12th year, we just now completed the base and bridge/bump crossing mechanism. It has not been driven yet. It looks stellar, but none of it is done or tested. You're not alone. |
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I'm seconding what everyone else has said - 30lbs is enough to do a lot.
In 2010 we got to our regional, and our kicking mechanism... didn't work at all. It was a nightmare, and dangerous. So between the regional and Champs we completely redesigned the kicker from scratch, in a single unit that we could bolt into our chassis and plug in, and be done. It's definitely do-able! The fact that what you have done is solid is fantastic. Better to have one thing completely finished than two things half finished, correct? |
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I have a question for all the people talking about the 30 pounds and how great it is. How can a robot truly be competitive if the electrical team doesn’t have time to test their wiring, the software team doesn’t have time to test autonomous routines, and the drivers don’t have time to practice? I’ve seen this type of thing occur many times at work, and it always delays projects. Mechanical engineers sometimes think the deadline for the project is their deadline and don’t leave any time for integration and debug.
Say you have a hypothetical team with very few resources, so they can only go to one regional and they can’t afford to build two robots. Let’s say the mechanical part of the team decides the shooter doesn’t need to be completed prior to bag-and-tag. They build a prototype shooter, but they never put it on a robot. The plan is to work on the shooter for a few weeks and attach it at the regional. It won’t go onto a robot until practice day, and the team will miss much of the practice session working on the build. System integration is the hardest part of engineering. In the real world the game balls have different densities, so your precisely controlled mechanical system is not so precise. In the real world things rarely work the first time and you have to study the problem to decide if it is mechanical, electrical, or software. This is why teams should be doing system integration throughout the season. Don’t wait until the end to test the system or you may quickly run out of time. I don’t believe a team with low resources can decide to just finish 30 pounds of the robot after bag-and-tag and truly be successful (OK, a low percentage will). These types of teams need to finish early giving the electrical team time to work out wiring issues, the software team time to test code and write autonomous modes, and the entire team time to make an objective decision about the drivers. You can build the most perfect mechanical system in the world, but without electronics, software, and drivers it will just sit there. Yes, we couldn't do it without the mechanical team either. Remember there are 3 robots on every alliance. Many alliances will likely pick one defender/feeder robot, and many will look for a good balancer. You don’t have to have a way to score balls. Make a basic feeder before bag-and-tag. Give your drivers plenty of time to practice. If you show yourself to be a great defender that doesn’t get penalties at the regional, you will likely get picked. |
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Wish we were close to being as far as you are Andy. As for Aren's bot - I can't even imagine us being close to where we are if we were building what he made, I think right now we're pretty close to where Dr. Joe is. That said, Dr. Joe, if you guys need anything machined or fabricated let some of the guys in the area know (I'm sure Brandon Holley would be willing to help out). |
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Yes, it is a high-risk situation. But it's also high-reward and it seems most people in this thread support taking the chance. |
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Don't worry, we're all almost out of gas. That said, it seems (from your post) that it's time you changed tactics from the engineer to the manager. Prioritize what needs to get done and what can be done after shipdate. Focus your team on only those things that absolutely need to get done and do them. Once shipdate passes prioritize what will go into your 30 LB withholding and then focus your team on that. Don't get discouraged ... we've all been there. All I got to say is, it's too bad you are not coming to GSR. I'd love to meet you as you are one of the people who has truely inspired me. |
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Somehow we dodged the Classic Blunder this year...and for the first time we're going to a scrimmage! Hopefully the problems we find with the robot won't keep us up too late for the next 3 days
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If it helps, we're a four-year veteran team with two blue banners hanging in the shop...and we haven't shot a ball yet successfully. You're not alone, Dr. Joe!
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@ Doug G; Doug brings up a good point on making sure all nut, bolts & screws, wires, as well as rivets, chains, lexan & ANY other components attached to your robot. I run the field at Suffield Shakedown & am amazed at how much loose material is picked off the field after every match. Most teams don't even realize they are missing anything. Yesterday a team lost a whole 4" c-clamp. I instructed nobody to pick it up. Before the robots were removed from the field I made an announcement that there was a large part on the field & that it should be removed. It was removed by the team in question.
You always hear from teams, Oh, it fits in there really tight, it won't move. Trust me it will. |
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The only problem with the 30-lbs witholding limit is that I haven't figured out how to package the 30-lbs of programming and calibration our robot really needs to be truly competitive....
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Believe me, I would love to have a practice bot, but I've yet to figure out a way for us to build one. Practice bots are nice in theory, but we've spent pretty much all of our $4000 robot budget already, and all of the time we had available to build at our shop. At this point of every season, we're pretty much completely tapped on budget and build time and simply don't have the resources to put a practice bot together. And yes, a practice bot will be just about as expensive as our full robot to be any good. We've got 10 Jags, 6 pneumatic wheels, a CIM-sim, 3 BB P60 transmissions, an entire kit chassis, two 6" performance wheels, poly cord, etc. etc. That adds up to a heck of a lot of money we don't have available for a practice bot.
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I wish we had a good excuse for not having a practice bot, besides "we're lazy"....
I think we're already a few days past "burn out". At least our one robot does most of what it is supposed to do. |
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1. The mechanical team says they are "on track" to deliver the complete mechanical system on time even as they load a mill and three phase generator into the van to finish machining some key parts on the drive to our scrimmage. 2. The electrical team is allowed access to robot for final wiring and integration once the robot is placed on the field. At that point they wrap sensors and switches in freshly chewed gum and throw them at the robot from the sidelines hoping that some of them stick. 3. Using binoculars and what they can over hear from the crowd as to where the sensors landed, the programming team develops a strategy for how to code the software and deploys it over the wireless link just prior to the start of each match. 4. The drive team plays with the controls to see what the robot does when they move each control. This process is greatly aided in the team numbers were painted on the bumpers so that they can recognize our robot. 5. After each match the pit crew gathers up the parts from the field and finds a new and interesting way to assemble them. This might be a slight exaggeration, but this was my first year, so their may have been slightly more order to the process than what I saw. |
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Also, we do not have a practice robot this year, but we are very very close, and could have if we had just committed the capital at the beginning of the season. If the entire robot is designed in CAD before any building, the building flies and takes a day or two. So when buying all your parts, you buy twice as much (cuz you should have spares anyway). If you manage to build your first robot soon enough (week 3 or 4), you can wait a bit to get all your second fabricated parts until you see some things you might want to tweak based on your testing. Then you build your second one in week 5 or 6, while practicing and doing code on the first, and you bag the second (cuz it's obviously way better) and the first is your practice machine. It's a little more capital to invest at the get go, but its also invaluable to have robot junk lying around for future prototyping, besides all the spares you now have. |
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Back on topic, we have typically suffered from this same mistake. Nearly every year there has been some component to the game that we put off until the last minute and it was always a kludge. This year we're doing a lot better, but there are still traces of that approach. Just look at the CAD, and anywhere it doesn't reflect the actual robot accurately, you can bet we spent at least 3 times longer building it than we needed to.
And I get caught expecting a little too much of our team too. I want us to make a great machine, but I have to realize that none of the kids have the design experience to make it happen as fast as I would like, and it doesn't do them any good for me to go home and design it myself. So I was perhaps asking a lot when I wanted the CAD completely done in week 3. Definitely don't forget about the 30lbs. A ball handling mechanism will be critical to serving an alliance well in eliminations, but it can be the simplest thing on the planet. Somehow attain balls and get them down the court, or keep them away from the the other team. I predict ball starvation to be really effective this year, but you could also make a shooting robot's life a lot easier by feeding balls directly to them. It sounds like you have something to offer in terms of the end game, so now its a matter of doing something effective in the minute and a half before that. |
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Our team spent the day on Saturday finishing up an arm with shooter (we may end up being able to score a ball or two yet...) meanwhile back in Michigan, they're popping off Double Triples and making it look easy as they watch the clock tick down for the last quarter of the match...
I will be honest, I teared up a bit watching my old pals playing at the Waterford Mott District Event. I wept for how amazing and inspiring MechWarriors, Las Guerrillas and HOT and others are. Not just this year but year after year. It was inspiring but it also made clear how far we have to go before out team can lay any claim to being Hall of Fame caliber team. All we can do is get through this year and do better next... To HOT and Las Guerrillas, one or both of you are almost certain to make it to Einstein again the year. I salute you, both. Joe J. |
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