View Full Version : under 2 sec Mini bot
nuggetsyl
30-01-2011, 18:02
I am starting to think is possible to get a mini bot up in under 2 secs.
thefro526
30-01-2011, 18:04
I think it's been proven that a mini-bot can climb the pole in less than two seconds.
I wonder how many people can figure out how to do it?
Today while at work I was doing some math on my phone and I got the theoretical time very nearly below 1 second.
How are you getting your minibots to do that?
So far we've gotten the bot up in 10 seconds, but we're running into difficulties for making it go faster with our tetrix wheel (not the best traction), and messing around with the gear ratios, and just finding where to distribute weight.
What kinds of designs are you guys using?
Yes.
Proof by example
http://www.chiefdelphi.com/forums/showthread.php?t=90114
Q.E.D.
(unless you are including the start of deployment as well?)
How are you getting your minibots to do that?
So far we've gotten the bot up in 10 seconds, but we're running into difficulties for making it go faster with our tetrix wheel (not the best traction), and messing around with the gear ratios, and just finding where to distribute weight.
What kinds of designs are you guys using?
I won't tell you exactly how. But, concerning weight distribution ideally your weight is pushing your drive wheel(s) into the pole, concerning gear ratios find the top of the power curve and eliminate extra gearing as each stage adds inefficiency, concerning tetrix wheel traction slit some surgical tubing down the middle and put it around the wheel with PVC glue to secure it (just an idea, haven’t tried it).
Good Luck
Tom Line
30-01-2011, 18:29
It's all in the design.
1. Minimize weight.
2. Increase efficiency (eliminate gears)
3. Maximize power through gear ratio and wheel size choice.
4. Profit!
There are also some other games you can play to increase the power of the system (legally).
Yes.
Proof by example
http://www.chiefdelphi.com/forums/showthread.php?t=90114
Q.E.D.
(unless you are including the start of deployment as well?)
Remember that that video is without a battery. Is there any minibot who has actually climbed the 8 ft with a battery in less than 2 seconds?
Swampdude
30-01-2011, 20:11
Those of us who can/have done it ;) aren't likely to show anything until competition, otherwise everyone will be doing it. Even then keeping them covered in the pit might be common. It's so easy to reconfigure these tetrix kits.
Garten Haeska
30-01-2011, 20:21
my mini bot goes up in 4-5 seconds and it only has one set of wheels powered and i plan to put it on both sets
Alpha Beta
30-01-2011, 20:21
Those of us who can/have done it ;) aren't likely to show anything until competition, otherwise everyone will be doing it. Even then keeping them covered in the pit might be common. It's so easy to reconfigure these tetrix kits.
I agree. Has anyone considered having a 3 second bot for Thursday and Friday, and saving the sub-2 second bot for Saturday as a secret weapon?
Cyberphil
30-01-2011, 20:25
I agree. Has anyone considered having a 3 second bot for Thursday and Friday, and saving the sub-2 second bot for Saturday as a secret weapon?
That is interesting. But even then, if it uses the same tetrix parts, and if another team has the parts needed, I think they could create it over lunch or something. I think it is a good idea to keep your design concealed, but you can keep it concealed even when you are using it in competition.
MagiChau
30-01-2011, 20:25
I agree. Has anyone considered having a 3 second bot for Thursday and Friday, and saving the sub-2 second bot for Saturday as a secret weapon?
I would say this is a bad plan since you are doing an unnecessary limit. Do not purposely weaken your team's capability to effectively complete the challenge. Do your best at qualifications so you can use the "secret weapon" during eliminations.
EDIT: after reading Cyperphil's post, if you want to really hide then cover the minibot with polycarbonate since its allowed.
davidthefat
30-01-2011, 20:26
Wait a minute here... So teams have already build (or at least prototyped) their minibots already? Our team only has the CAD and a prototype made with servos. We are behind.
edit: our design is so crazy that I doubt that any team can fabricate the deployment system and the minibot in the 2 day period.
MagiChau
30-01-2011, 20:29
Wait a minute here... So teams have already build (or at least prototyped) their minibots already? Our team only has the CAD and a prototype made with servos. We are behind.
My team started prototyping the day we got the FTC kit. We went through I think at least 4-5 different prototypes already. Forgot if our current minibot is going to be final design.
Those of us who can/have done it ;) aren't likely to show anything until competition, otherwise everyone will be doing it. Even then keeping them covered in the pit might be common. It's so easy to reconfigure these tetrix kits.
So coopertition is not a big thing for you? I mean, you won't be lending your minibot out to other teams, or will you? Scouting reports will likely tag your team as "keep 'em away from the pole" even if for only a few seconds. We're considering a tinted polycarbonate box which may or may not have a minibot aboard. How fast? Thaaaaat fast! wanna see it again? :)
Cyberphil
30-01-2011, 20:32
Wait a minute here... So teams have already build (or at least prototyped) their minibots already? Our team only has the CAD and a prototype made with servos. We are behind.
edit: our design is so crazy that I doubt that any team can fabricate the deployment system and the minibot in the 2 day period.
Yes. We have had about 4 prototypes, all along the same lines. No final product has been created, but proof of concept has been shown. We figured that since it is such a huge part of this game, it was necessary to spend a significant amount of time on it.
I agree that the toughest part would be to create the deployment system also. Depending on what teams use to start the minibot, it will be very tough to fabricate something at competition that deploys it, or even modify their current design to allow for the new minibot.
MagiChau
30-01-2011, 20:39
So coopertition is not a big thing for you? I mean, you won't be lending your minibot out to other teams, or will you? Scouting reports will likely tag your team as "keep 'em away from the pole" even if for only a few seconds. We're considering a tinted polycarbonate box which may or may not have a minibot aboard. How fast? Thaaaaat fast! wanna see it again? :)
Haha, thanks for that joke. But don't forget to tease people with maybe a wheel.
Henry Williams
30-01-2011, 20:48
Yes.
Proof by example
http://www.chiefdelphi.com/forums/showthread.php?t=90114
Q.E.D.
(unless you are including the start of deployment as well?)
The only problem is you guys don't have the battery on in that video, that battery is very heavy and will slow you down. Also if you were thinking of leaving the battery on your FRC robot just remember the 12x12x12 rule won't let you do that.
Mike Schreiber
30-01-2011, 23:56
Does anyone have specs on the TETRIX motor with the gearbox removed?
nitneylion452
31-01-2011, 00:05
Does anyone have specs on the TETRIX motor with the gearbox removed?
I would check the legality of that in the Q&A. In the current context of the rules, it seems like it may be legal to remove the gearbox, but it's better to be safe than sorry.
Grim Tuesday
31-01-2011, 00:07
I would check the legality of that in the Q&A. In the current context of the rules, it seems like it may be legal to remove the gearbox, but it's better to be safe than sorry.
Q&A has ruled that it is legal.
nitneylion452
31-01-2011, 00:09
Q&A has ruled that it is legal.
Well, turn me over and call me Sally. Looks like I should have done a search.::rtm:: ::ouch::
rocketeer1
31-01-2011, 00:09
So with the max power outputs of the motors and the weight of two motors and a battery, you could calculate the absolute maximum minibot speed. Anybody know how much the motors and battery weigh?
Vikesrock
31-01-2011, 00:12
Does anyone have specs on the TETRIX motor with the gearbox removed?
http://www.chiefdelphi.com/forums/showpost.php?p=1005008&postcount=15
artdutra04
31-01-2011, 00:17
Two seconds up the pole is definitely feasible. :D
Two seconds, from breaking the plane to hitting the trigger, that's the challenge.
Make the weight work for you so increases traction
MrForbes
31-01-2011, 00:29
I expect that if you're using any tetrix parts besides the bare motors, wheels, and battery, you're not building the fastest minibot you could :)
Vikesrock
31-01-2011, 00:31
I expect that if you're using any tetrix parts besides the bare motors, wheels, and battery, you're not building the fastest minibot you could :)
I wouldn't be surprised to find out that if you are using the Tetrix wheels you are not building the fastest minibot you could.
MrForbes
31-01-2011, 00:33
You're probably right. Sheet aluminum or polycarbonate and latex tubing is looking pretty good.
thefro526
31-01-2011, 08:09
I expect that if you're using any tetrix parts besides the bare motors, wheels, and battery, you're not building the fastest minibot you could :)
I wouldn't be surprised to see some of the faster mini-bots using tetrix metal as well. The few pieces I played with were extremely light.
Tetraman
31-01-2011, 08:50
The real race will be deployment.
Can you deploy faster than 1 second?
Yes.
Proof by example
http://www.chiefdelphi.com/forums/showthread.php?t=90114
Q.E.D.
(unless you are including the start of deployment as well?)
I'm pretty sure that minibot didn't have a battery pack onboard :rolleyes:
Our team has protoyped two minibots with good results, and I still think we are far behind. A reliable, fast, rugged deployment method is challenging. Do not underestimate it.
I second all the comments regarding using the required masses to improve wheel traction.
Our team will probably not be disguising our minibot in any way. Right now, it just kind of "feels wrong."
If you have enough man-hours to devote to it, a sub-2-second climb is doable. We do not have enough man-hours.
MrForbes
31-01-2011, 10:43
I hear one FRC team in Phoenix is getting a whole other ex-FRC team (now FTC team) to develop their minibot. Yeah, it can take a lot of engineering effort to make an outstanding performer.
Tytus Gerrish
31-01-2011, 10:48
How are you getting your minibots to do that?
So far we've gotten the bot up in 10 seconds, but we're running into difficulties for making it go faster with our tetrix wheel (not the best traction), and messing around with the gear ratios, and just finding where to distribute weight.
What kinds of designs are you guys using?
ditch the gearheads.
Under 2 seconds, huh? I'll bet that if we see some under 2-second MINIBOTs, we'll also see some batteries that are overcharged and leaking by the end of competitions.
Tytus Gerrish
31-01-2011, 13:08
Under 2 seconds, huh? I'll bet that if we see some under 2-second MINIBOTs, we'll also see some batteries that are overcharged and leaking by the end of competitions.
universal smart charger $35
http://static.zoovy.com/img/zephyrsports/-/airsoft/batteries/smart_charger.jpg
it's an essential piece of equipment for Airsoft. it saves you from destroying your batteries. i suggest you grab one of you are worried about overcharging
Jesse isn't worried about overcharging per se.
They're saying that to achieve sub-two second climbs, those minibots will be depending on an overcharged battery (to squeeze that extra little bit of performance from) to do so, and thus by the end of competitions, they'll be damaged.
Brandon Holley
31-01-2011, 16:34
universal smart charger $35
http://static.zoovy.com/img/zephyrsports/-/airsoft/batteries/smart_charger.jpg
it's an essential piece of equipment for Airsoft. it saves you from destroying your batteries. i suggest you grab one of you are worried about overcharging
I believe the chargers we got for the FTC batteries are almost identical to this (without the branding/different color)
-Brando
we just got 1.6, i will post the youtube soon once it is uploaded.
I'm pretty sure that minibot didn't have a battery pack onboard :rolleyes:
You really want to count on that? ;)
sdcantrell56
31-01-2011, 20:35
Possible without a shred of doubt...
LH Machinist
31-01-2011, 21:42
Does anyone have specs on the TETRIX motor with the gearbox removed?
I just ran it without the gearbox and no load: @12v 7700 RPM, @14v 9100RPM. I'm not sure about the available torque.
speedbuggy76
31-01-2011, 22:25
Do we have a video Hailey?
Our minibot is just over 2 seconds, with battery. We are using the tetrix wheels, but they've been modified (in a legal way). From what I've heard, we're still working on the CAD of the deployment mechanism.
ditch the gearheads.
'Scuse me? ;)
Our minibot climbs the pole in 2.14sec (at least thats what we were told by a comment) and it is built solely from the TETRIX kit's parts.
i'm pretty sure that with a bit improvement or Weight reduction we will be able to go up in less than 2 sec.
Our minibot's first test run-
http://www.chiefdelphi.com/forums/showthread.php?t=90373
Swampdude
05-02-2011, 19:12
Here's a 1.8 second run:
http://www.youtube.com/watch?v=NnCfXzmwe6o
And here's the 1 second deployment:
http://www.youtube.com/watch?v=h2HWZeGKp5I
biancs15
05-02-2011, 19:26
Here's a 1.8 second run:
http://www.youtube.com/watch?v=NnCfXzmwe6o
And here's the 1 second deployment:
http://www.youtube.com/watch?v=h2HWZeGKp5I
Very nice minibot and deployment mechanism. Great use of springs. Very simplistic. With the minibot and it's deployment this year I believe that the designs that are simpler will be more effective. Great work!
You really want to count on that? ;)
:eek: did it?
Chickenonastick
05-02-2011, 22:43
I would assume some of these minibots don't have gearboxes.
I would assume some of these minibots don't have gearboxes.
Or modified gearboxes;)
Cybergnomes have just done it! 1.88 sec! With room for improvement! :yikes:
BIGWILLI2081
06-02-2011, 14:13
Here's a 1.8 second run:
http://www.youtube.com/watch?v=NnCfXzmwe6o
And here's the 1 second deployment:
http://www.youtube.com/watch?v=h2HWZeGKp5I
Nice job! I'm assuming you will modify you're deployment to 18 inches.
$~-M.E.C-~$
10-02-2011, 22:44
Team 3015 here. We have made a mini robot that went up in 4 seconds or so with the battery on it. I was just wondering if that is considered good or bad?:ahh:
4 seconds as of right now seems a little below average on CD. However, I think that you'll find that at whatever compitition you go to that 4 seconds will certainly be competitive and you will win your fair share of minibot races.
Good Luck
Grim Tuesday
10-02-2011, 23:10
Im proud to say that we can deploy in .3 seconds, so if anyone wants to loan us a minibot...
Team 3015 here. We have made a mini robot that went up in 4 seconds or so with the battery on it. I was just wondering if that is considered good or bad?:ahh:
Any team that gets a minibot to climb has done well. It isn't a matter of good or bad, just a question if your design is going to be more or less competitive measured against other minibots. According to many posts on this forum, there are several minibots able to climb in 2 or less seconds and many have indicated times in the 3 second range. If you want to improve your time, consider looking through this and other related threads for some ideas to help your team out. Consider modifying your gear ratios and reducing weight to reduce your climbing time, and keep trying to improve!
Tom Line
11-02-2011, 00:27
Any team that gets a minibot to climb has done well. It isn't a matter of good or bad, just a question if your design is going to be more or less competitive measured against other minibots. According to many posts on this forum, there are several minibots able to climb in 2 or less seconds and many have indicated times in the 3 second range. If you want to improve your time, consider looking through this and other related threads for some ideas to help your team out. Consider modifying your gear ratios and reducing weight to reduce your climbing time, and keep trying to improve!
Exactly.
Also remember the proof is in the pudding. If you go and your minibot consistently climbs the tower, that makes you a very strong contendor no matter what.
Many folks tend to.... "overstate" the potential of their robot/minibot. Wait till you see a couple competitions. After all, the minibot is not part of the allowance and as such you can work on it pretty much anytime to improve it.
Exactly.
Also remember the proof is in the pudding. If you go and your minibot consistently climbs the tower, that makes you a very strong contendor no matter what.
.
This is excellent advice from a very consistent hanging team last year. Just like last year's bonus, many will attempt, but statistically few will succeed. At an absolute minimum, it is a 10 point endeavor if you consistently succeed. It takes a lot of tube hanging to make up those 10 points.
Zuelu562
11-02-2011, 09:39
At an absolute minimum, it is a 10 point endeavor if you consistently succeed. It takes a lot of tube hanging to make up those 10 points.
In fact, it takes at least 3 tubes on the top row (3 in a logo in the middle row works too) to get 10 points. That's huge.
anyone using omin mini wheel for the minbot
Tytus Gerrish
11-02-2011, 15:06
anyone using omin mini wheel for the minbot
WHY? making a pole-dancing robot?
WHY? making a pole-dancing robot?
I've been hacking away at that joke all season.
"Presenting Team Fusion's mini-bot, Miss Candy!"
:p
Radical Pi
11-02-2011, 22:12
We just made 3 seconds from start of deployment to triggering. .3 seconds to deploy (plus maybe .1 for the minibot clamp to release), 2.85 seconds for the climb itself.
I do hope that we can regularly deploy though. The robot will probably be able to drive tomorrow and we can do a full test of how difficult it is to align and deploy, but for now anything could happen. We tried to design our robot with deployment in mind though. The camera is mounted on a servo so we can turn it around to align for deployment, and supposedly our deployment tray is able to self-align during deployment as long as the brakes aren't on.
What about trading minibots? Who has a flexible enough deployment system to handle a variety of minibots? It looks like our tray will be able to deploy anything that has a vertical neck no more than ~3" wide. Have any teams been actively collaborating with others to build compatible minibots?
nikeairmancurry
11-02-2011, 23:31
It's nice to hear all these claims about how fast you climb and deploy.. But I wanna see you at the pole at that ten second mark deploying and be the first one up.. You may have the fastest minibot out there.. But means nothing if you aren't at that pole at the second that base lights up..
Getting to that tower will be the hardest thing to do... You have to cover alot of area to get there...
Grim Tuesday
12-02-2011, 00:06
It's nice to hear all these claims about how fast you climb and deploy.. But I wanna see you at the pole at that ten second mark deploying and be the first one up.. You may have the fastest minibot out there.. But means nothing if you aren't at that pole at the second that base lights up..
Getting to that tower will be the hardest thing to do... You have to cover alot of area to get there...
And that is why we used tank treads with supershifters this year. Speed to the tower, power through any opposition.
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