Chief Delphi

Chief Delphi (http://www.chiefdelphi.com/forums/index.php)
-   Technical Discussion (http://www.chiefdelphi.com/forums/forumdisplay.php?f=22)
-   -   Brainstorm: Improving the FRC bumper rules (http://www.chiefdelphi.com/forums/showthread.php?t=85435)

Zflash 22-04-2010 10:26

Re: Brainstorm: Improving the FRC bumper rules
 
I don't like bumpers and 1319 has only used them the years where they were mandatory. I agree with everything Tom has said above and could not have said it better. Instead I add an alternative to the alliance identification issue. Right now every robot has a required signal light that arguably evryone can see from the stands. You know when your robot is not moving look to see what the signal light is doing right? So why not have interchangeable robot signal lights that are either blue or red much like back in 2003 and before as manyy have already suggested. A link below shows a great possibility.

http://www.ab.com/signaling/towerlights/855t.html

gren737 22-04-2010 10:44

Re: Brainstorm: Improving the FRC bumper rules
 
Note, I'm donning my firesuit now as I type this.


I've been thinking about this ALOT lately. I'm not a fan of bumpers, primarily because of the restrictive rules, but I do see the reason for them.

I do realize bumpers are all or nothing, either every robot has them, or they don't. Making them optional will just result is robots without bumpers tearing up the bumpers on the ones that do.

Looking back at it, there is one major thing that has changed as the bumper rules have come about. The power of the motors included in the kit.

I believe 2005 was the first year of having 4 cims and we also had the big cims that year (I think). This was also one of the first years teams started building mega drive trains. Previous years had mostly used the bosch drill motors for drivetrains. As the power of the drivetrains increased do did the damage to robots. Now teams are building mega (up to 6) motor drive trains with shifting transmissions capable of doing massive damage to another bot or field element.

I'm not sure if it would be a major step backwards but what if FIRST restricted the motors in the kit, or amount of motors used in the drivetrain in order to lessen the damage that can be caused by a robot and thus remove the bumper rules? Not only would it loosen up the robot rules a bit, but it might help some of the KOP cost issues as well?

Just a suggestion, and I'm really not sure if it's even something I support or not, just throwing it out there. Just to be clear, I am in favor or less rules, not more. :)

pfreivald 22-04-2010 11:03

Re: Brainstorm: Improving the FRC bumper rules
 
I like the standard bumpers, with the standardized colors for alliance identification. The only change I personally would like to see is an allowance for gaps in the bumpers as we have seen in previous years (which I think only wasn't allowed this year because it wasn't particularly necessary given Overdrive's other design limitations).

Mr.G 22-04-2010 12:13

Re: Brainstorm: Improving the FRC bumper rules
 
Quote:

Originally Posted by squirrel (Post 956608)
The only problem I've been concerned with is the wording of the rules. It would be nice if the GDC could figure out how to say what they mean, in easier to understand language, the first time they write the rules. This doesn't seem to be a problem with most of the other parts of the manual.

I couldn't have said it better myself.

I don't like bumpers. I miss the sound of 2 robots coming together at full speed. We have to spend too much time reading on how to build them and then building them. It is a week’s worth of work that could be actually used to teach useful stuff to the students.

I also don't like having to modify the bumpers every time a different ref looks at them. We didn't have to touch them our first event, but had to make major changes at our 2nd event and the Championship. The rules were constantly being reinterpreted throughout this year. Mostly because they were written poorly. The GDC does a great just with the rest of the rules but somehow seems to fall short on bumpers.

efoote868 22-04-2010 12:22

Re: Brainstorm: Improving the FRC bumper rules
 
I loved the easy identification of alliances. I know members of my team spent large amounts of time fabricating our bumpers, and they did a superb job. Hopefully one of them will post pictures of the construction, and the mechanisms used to switch them out.


As far as robot identification, bumpers were a nice standardization. Other ways to identify robots such as lights or covers wouldn't be as easy to standardize as bumpers are.

Including bumper materials in the kit and a mounting system for the kit bot may be a must in the future.

Tristan Lall 22-04-2010 14:02

Re: Brainstorm: Improving the FRC bumper rules
 
When this came up last year, here's what I said:
Quote:

Originally Posted by Tristan Lall (Post 876223)
The simplest and most productive way to fix this is to specify a reference bumper configuration that is by definition legal, and ask inspectors to qualitatively evaluate teams' actual configurations in comparison to this standard. As long as the bumper meets some very basic dimensional and functional criteria (e.g. bounding size, weight and tactile qualities), there's little value in making a regulatory distinction between things like Ø2.5 in pool noodles and Ø2.0 in pool noodles—because realistically, they both do almost the same thing. Now of course, this makes the rule subjective rather than objective, and will mean that we'll be depending on the inspectors to say "close enough", rather than follow precise criteria. In this case, I think that's fine, because bumpers have one fundamental purpose: to reduce damage to robots. If we see a mix of robots that are each—according to the inspectors best guesses—between 75% and 200% effective, relative to the reference design, that's not a problem. And if so, who really cares whether they used foam rubber bricks, pool noodles or hippopotamus tenderloins? Also, teams can't complain much about subjectivity if they're offered a perfectly good reference design to emulate, and choose not to—the reference design should be teams' first choice, unless they have a good reason to deviate.

I think that all continues to hold true.

Additionally, I would support the idea that bumpers be made optional again, as long as it's clear that robots running without them would not draw more penalties against the opponent (despite being more likely to be damaged), and that they would have to identify themselves in an equivalent way (e.g. coloured, numbered placards in the bumper zone).

Mandatory bumpers do have one big advantage: they save teams that build the robot to the full 38 in × 28 in limits from huge trouble when the frame twists, or their tolerances are off. This can be obviated with a simple note in the rules: "Build your robot smaller than the maximum limits of size to account for manufacturing tolerances and distortion due to damage suffered during gameplay. As a rule of thumb, you should consider building the robot at least 1 in smaller than each limit."

Things like supporting the entire backing of the bumper are not helpful. If a bumper breaks, who cares? It's a bumper. Either fix it with some sort of gusset, or cut it and call it two bumpers. The rules should be written to permit a simple, effective resolution to a broken bumper, instead of imposing a basically-worthless constraint on everyone—which, due to the phrasing, affects teams even if there's no reasonable chance that their bumpers will break. During inspections at three events, I saw two teams with essentially unsupported bumpers along two sides (including one at the Championship...). They were forced to add structure to support the backing of their bumpers—even though, in all likelihood, the bumper backing itself was much stronger than the structure. By contrast, I saw more than a dozen teams that had small gaps behind their bumpers which were technically illegal, but which posed no real problem from an engineering perspective. And yet, the rule is clear: they must support the entire length of each bumper with the robot's structure or frame. So mounting points were adjusted, or bumpers shimmed. This wasted a lot of time, both for teams and inspectors. But basically: this constraint is useless, and even counterproductive—either get rid of it, or write in a clause that specifically allows inspectors to override it based on their engineering judgment.

Bumper colours were very helpful for identifying alliances, but quite the opposite for identifying teams. With the location of the bumpers this year, and the fact that many robots were low, it meant that a lot of robots were hard to identify from a distance or on the webcast videos. While in the past, unique bumpers were easy ways to identify robots, this year, everyone had to rely more closely upon the team numbers (which are quite invisible in many webcasts). I'd be quite happy to see the rules allow the bumpers to be any colour, except for an inset patch (at least 12 in long) corresponding to the alliance colour, and containing the team numbers in white.

Bumpers should be required to be removable in 20 s per bumper segment. No exceptions. This isn't rocket science, but because the rules suggest threaded fasteners, teams tend to go with complicated arrangements that require the insertion of hand tools into tight spaces. Teams will rapidly discover the existence of various spring pins if forced to design bumpers to be removed quickly.

Finally, though it's not technically part of the bumper rule, the frame perimeter rule was a significant annoyance. Hopefully there won't be any reason to need this next year—but if it does come back, tighten the definition.

AdamHeard 22-04-2010 14:10

Re: Brainstorm: Improving the FRC bumper rules
 
Quote:

Originally Posted by Tristan Lall (Post 956766)
Things like supporting the entire backing of the bumper are not helpful. If a bumper breaks, who cares? It's a bumper. Either fix it with some sort of gusset, or cut it and call it two bumpers. The rules should be written to permit a simple, effective resolution to a broken bumper, instead of imposing a basically-worthless constraint on everyone—which, due to the phrasing, affects teams even if there's no reasonable chance that their bumpers will break. During inspections at three events, I saw two teams with essentially unsupported bumpers along two sides (including one at the Championship...). They were forced to add structure to support the backing of their bumpers—even though, in all likelihood, the bumper backing itself was much stronger than the structure. By contrast, I saw more than a dozen teams that had small gaps behind their bumpers which were technically illegal, but which posed no real problem from an engineering perspective. And yet, the rule is clear: they must support the entire length of each bumper with the robot's structure or frame. So mounting points were adjusted, or bumpers shimmed. This wasted a lot of time, both for teams and inspectors. But basically: this constraint is useless, and even counterproductive—either get rid of it, or write in a clause that specifically allows inspectors to override it based on their engineering judgment.

I agree.

We usually run the west coast drive, a system that is extremely minimal and elegant in construction. The fact that we had to do this in 2009 to fully support the bumpers is silly to me, we could've supported them at a few places and be done with it. That doubled the amount of welding and parts in our frame, along with adding a pound of useless weight and making the frame ugly.

It's a little insulting for FIRST to say, hey, we don't trust you to build a frame right, so here are bumpers. I can live with that, but when FIRST says we further don't trust you enough to put bumpers on there without them breaking, so you MUST support them the entire length, that's just ridiculous.

Tetraman 22-04-2010 15:01

Re: Brainstorm: Improving the FRC bumper rules
 
Do the bumpers need to be as thick as they are? What if we chopped down their outward extension?

I always liked the bumpers but thought it was rather clunky and needs some refinement. Not sure what else to say though.

GaryVoshol 22-04-2010 15:42

Re: Brainstorm: Improving the FRC bumper rules
 
I really liked the red/blue colors this year. It made telling alliances apart very easy, even moreso than last year when you might have a red trailer pulled by a blue robot. I understand the team image issues, but perhaps that can be addressed in another manner.

I didn't like most of the removable bumper covers I saw - they looked shoddy. Add to that some very amateurish numbering methods. C'mon, let's try to make these machines look like the high-tech and high-class robots that they (usually) are.

I agree that the rules are too complex, without getting to what the GDC really wants. When too many smart teams can misinterpret the rules and show up with defective bumpers, the rules aren't written clearly enough.

I'm not sure why the frame perimeter cannot have concavities. As long as each section of the frame is at least 6" long and protected by an adequate bumper, why can't there be a pocket?

As for the bolthead and rivet rule, don't get me started ... :mad:

nikeairmancurry 22-04-2010 15:48

Re: Brainstorm: Improving the FRC bumper rules
 
Quote:

Originally Posted by GaryVoshol (Post 956814)
I really liked the red/blue colors this year. It made telling alliances apart very easy, even moreso than last year when you might have a red trailer pulled by a blue robot. I understand the team image issues, but perhaps that can be addressed in another manner.

I didn't like most of the removable bumper covers I saw - they looked shoddy. Add to that some very amateurish numbering methods. C'mon, let's try to make these machines look like the high-tech and high-class robots that they (usually) are.

I agree that the rules are too complex, without getting to what the GDC really wants. When too many smart teams can misinterpret the rules and show up with defective bumpers, the rules aren't written clearly enough.

I'm not sure why the frame perimeter cannot have concavities. As long as each section of the frame is at least 6" long and protected by an adequate bumper, why can't there be a pocket?

As for the bolthead and rivet rule, don't get me started ... :mad:

My teams main issue with the bumper rules this year. Our design had two concavities, those such allowed the ball to roll under the robot without going the 3 inches under the robot. It was a genius idea on our part, and the refs at our first event thought it was awesome.

When we were asked to change the design, our main issue was, what advantage did we gain by doing this? We were never given an answer by the GDC or and Inspector, but we did comply and change the design in about two hours at the Troy District Event.

pfreivald 22-04-2010 17:21

Re: Brainstorm: Improving the FRC bumper rules
 
Quote:

Originally Posted by nikeairmancurry (Post 956819)
When we were asked to change the design, our main issue was, what advantage did we gain by doing this? We were never given an answer by the GDC or and Inspector, but we did comply and change the design in about two hours at the Troy District Event.

I have no problem with the answer to many rules questions being, "Because we said so."

I usually revise that when my students ask that question of me. I say, "To make it harder."

billbo911 22-04-2010 17:37

Re: Brainstorm: Improving the FRC bumper rules
 
Quote:

Originally Posted by ratdude747 (Post 956605)
maybe beanbag bumpers? :D

Can you imagine?

I sure hope you don't mean the same kind of Bean Bags used for furniture. Those things were very popular when I was in College. They were cheap and comfortable, for the first 20 minutes. (Don't ever fall asleep in one, you will wake up with the worst back ache of your life!)

The problem with them is that they really don't handle abuse very well. Once abused, they start multiplying. Little baby white bean bags start showing up on the floor. Once they start multiplying, they never stop. The next thing you know, those baby beans are all over the place. You will find them in the most unlikely places, like in lamp shades two stories above the floor. (Can you say "Tribbles"?)

Any way, just imagine the exploding cloud of baby beans as two robots smash headlong into each other? It would be better than the 4th of July!

http://www.youtube.com/watch?v=TYb_Z...eature=related

Lil' Lavery 23-04-2010 01:02

Re: Brainstorm: Improving the FRC bumper rules
 
Quote:

Originally Posted by Aren_Hill (Post 956645)
I forget what year it was rookies were deemed incapable of making a robot with any level of ability.

And having a rougher interaction helps teach not only robust construction, but designing for ease of maintenance and replacement.

The bottom line, Aren, is that sometimes you have to look beyond the competition to see the greater meaning of FIRST. I do believe that bumpers are one of these times.

There are plenty of rookies capable of building great bots, and there are plenty that are not. Perhaps I shouldn't have used "rookie" as my descriptor, as there are plenty of veteran teams who have the problems I'm alluding to, but it quickly got my point across to a reasonably astute reader.

I've seen plenty of "adventurous" uses materials and frame design in my years in FIRST. And plenty of these uses have ended up failing under the heat of competition. I've even seen some very sturdy frames get quite bent out of shape by some overzealous play by other machines. I'm not saying we should reward "bad" design, but I am saying we should be somewhat forgiving of it in terms of helping the greater mission of FIRST.

Ask yourself, which is going to be more inspiring to a student. Showing up with a scrapped-together robot that barely runs, takes plenty of help to pass inspection (including needing to make bumpers), but ultimately gets out on the field and drives around. Or one that drives around for two matches, then gets smashed into the wall and broken and doesn't see the field again for the rest of the day as your fix it?

Obviously neither situation is ideal, but the joy I've seen from teams just as their robot moves is much greater than the joy I've seen from teams who don't see the same achievement. I'd rather have the teams at least come away from the event with a robot that didn't get smashed to pieces, and I think they would all say the same thing.

Maybe it forces the elite teams to change their designs some to meet bumper rules, but ultimately I think it does FIRST all the better. It's the lesser of two evils, in my mind. And not to mention, anything to help make sure I have functional alliance partners throughout qualifications is a good thing, in my book.



More related to the topic at hand, I do agree that some of the restrictions on materials, backing, shape, and coverage need to be adjusted to make more sense and allow for more creative designs. Specifically making it easier to create oddly shaped frames, concavities, curves, sloped frames, and articulated frame members.

I would like to keep the SOLID red/blue colors for the entire length of the bumper, though. Introducing team colors to the bumpers will take away much of the simplicity of the red/blue rules (or require more strict rules about bumper/frame shapes to facilitate "color on the corner" or similar rules, which still won't be as effective as the current situation). I would suggest more strictly enforcing team number size and color rules, and perhaps forcing number colors to be white to increase visibility.

Aren_Hill 23-04-2010 01:08

Re: Brainstorm: Improving the FRC bumper rules
 
Thats the biggest reason my vote goes under "optional", if a team feels the robot won't take a beating, easy answer, make bumpers.

I like Eric's wording of "highly recommended"

Anything that forces 254 and 968 to hide parts of the machine is doing a disservice to everyone from an inspiration standpoint.

Vikesrock 23-04-2010 06:32

Re: Brainstorm: Improving the FRC bumper rules
 
Quote:

Originally Posted by Aren_Hill (Post 957052)
Thats the biggest reason my vote goes under "optional", if a team feels the robot won't take a beating, easy answer, make bumpers.

The problem is that many of these teams that will build robots that can't take the punishment are the same teams that would not build bumpers for their robot.

I agree with much of what has already been said by others in this thread

1. Keep the red/blue bumpers all the way around. I would not be mad if they made building two sets mandatory and got rid of the covers, but I won't go so far as to suggest it be added.

2. Mandatory white numbers. For every team that loses their good looking non-whit numbers (eg. 67) 10 teams will be gaining clear readable numbers from both in the stands and on the webcast. We originally painted ours black, it looks fine in the shop. After watching webcasts we decided to repaint them white on Thursday.

3. Go back to 2009 style coverage % + cover every corner (dependent on game). In this game I think requiring full coverage was fine, I just hope it's not here to stay if the bumpers move back down.

4. Move bumper height back down. I'm just assuming this one will happen when the bumps disappear.

5. Allow "minor protrusions" along the entire projection of the frame perimeter as long as they're < 3/4". This should fix a lot of the nastiness that occurred this year (moving the bumpers back should help too.

6. Relax the fully supported rule. I would prefer they just let us figure out how to support them, but I would be ok with a % or a maximum span or both.


All times are GMT -5. The time now is 09:53.

Powered by vBulletin® Version 3.6.4
Copyright ©2000 - 2017, Jelsoft Enterprises Ltd.
Copyright © Chief Delphi