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Tim566
02-25-2006, 02:57 PM
i was wondering are there any robots out there that can right themselves if they fall over during the competition? In other words, can any robot can stand itself back up should it accidentally tip over during the competition? I don't really see many bots having that ability this year as there was last year. Please feel free to share your thoughts and comments on the subject even if your robot does not have the ability to right itself.

Koko Ed
02-25-2006, 03:13 PM
i was wondering are there any robots out there that can right themselves if they fall over during the competition? In other words, can any robot can stand itself back up should it accidentally tip over during the competition? I don't really see many bots having that ability this year as there was last year. Please feel free to share your thoughts and comments on the subject even if your robot does not have the ability to right itself.
Most of the time when a robot was able to correct a fall it was due to their arm design. There are no arms this year so no way to correct a fall. Once you're down, you're down for the count.

Stuart
02-25-2006, 03:15 PM
Ohh god now all I can think about is our robot tiping over. . . .

Tim566
02-25-2006, 03:21 PM
believe me its been blazing through my mind for weeks now I was just wondering if any team took measures to correct the tipped cow situation... because quite a few of robots seem to be built taller with more top weight making them more susceptible to being tipped over

StephLee
02-25-2006, 03:23 PM
Ohh god now all I can think about is our robot tiping over. . . .

Happened to us at our last practice. A ball got between us and the ramp, and...boom. *shudder*

Nuttyman54
02-25-2006, 03:25 PM
I KNOW! you just shoot the balls down very rapidly and the reaction force will tip it back up!!! but seriosly, we don't have a tipping problem (thank god) in testing we rocked it all the way back to about 45-50 degrees and it still righted itself when we let go. Yay for low CG!

Koko Ed
02-25-2006, 03:26 PM
Tipping will be a very common occurance this year:
1. Because of so many tall robots
2. Because of the steep angle of the ramp
3. Because of the physical nature of this year's game.

We tried to combat this by building a robot that is under 3 feet tall but there is no garuntee that we won't get tipped over (I remember at IRI last year after Rush Robotics arm exploded intp pieces they took it off and just ran thier hulk on the floor for the next match and they still ended up on thier back (I think they ran up a wedge bot).

Beth Sweet
02-25-2006, 03:28 PM
As one of the technical mentors showed me (as I was screaming at him), it would take a pretty good fall for us not to be able to get back up. I think that they have so much weight in the front that it just pops back up again.

Tim566
02-25-2006, 03:31 PM
similar thing happened with ours but due to quick thinking by the driver throwing the drive wheels in reverse as the front of the robot went airborne thus the front slammed down bending the battery holder slightly due to the impact of the 120 lb robot slamming back down. you can imagine the collective gasp that occurred or maybe you experienced it yourself

Steve S.
02-25-2006, 03:42 PM
we may have a problem with our bot, its .2" under the 5 ft limit :ahh:

11 Days til FLR!!!

Tim566
02-25-2006, 03:45 PM
As one of the technical mentors showed me (as I was screaming at him), it would take a pretty good fall for us not to be able to get back up. I think that they have so much weight in the front that it just pops back up again.
front weight would only help if your robot tipped back but supposed it gets tipped over forward while being rammed.

Anyway I am currently trying to figure out how to reduce the chance of tipping over because a sideways robot is essentially useless...

Nuttyman54
02-25-2006, 03:47 PM
we may have a problem with our bot, its .2" under the 5 ft limit :ahh:

Height isn't going to be as much of a problem as weight distribution. A robot that is exactly 5 feet tall, but has nothing but PVC and netting above 2 or 3 feet should be just fine. Only those who have motors and launchers (or other heavy items) up high should be worried. Careful driving and knowing the limits of your machine can also help you from getting tipped over. Good luck to all teams!

Koko Ed
02-25-2006, 03:49 PM
we may have a problem with our bot, its .2" under the 5 ft limit :ahh:

11 Days til FLR!!!
You guys seemed to get up the ramp pretty easily at Penfield so I think you'll be alright so long as no one is pushing on you.

Michelle Celio
02-25-2006, 03:53 PM
We tip kinda easily if we run over a poof ball to fast, but we have gotten used to it and realized how to fix it, I don't know how the driver does it but he does a good job of it. We've had several close calls but he's fixed them all. But as for part of the robot helping, we don't have that, but I seriously wanted to. The only time we can't fix our selfs is when it comes time for the ramp.

Now that I've said this, watch us flip at regionals.

It'll be our luck

Tim566
02-25-2006, 04:16 PM
can anyone think of a way to reduce the risk of tipping without redesigning the robot or adding much weight? ( our robot is at the weight limit assuming our scale is accurate but I am hoping the scale added weight to the robot that way we have room to make little add-ons come practice day)

Starke
02-25-2006, 04:27 PM
to solve our problem with tipping, #340 has designed a wheelie bar that comes down when needed to keep the robot down while going up the ramp. it weighs all together including the pneumatics 4 pounds.

Tim566
02-25-2006, 04:29 PM
to solve our problem with tipping, #340 has designed a wheelie bar that comes down when needed to keep the robot down while going up the ramp. it weighs all together including the pneumatics 4 pounds.
well that wouldn't work for us but maybe we could use a light weight wheelie bar just have it pulled in slightly or something

Donut
02-25-2006, 04:34 PM
Unless you're gunning for the ramp, I don't think you seriously need to be worried about tipping. Our robot last year was unable to right itself, and it extended up to 13 feet in the air. We got hit with our robot holding tetras at least 9-10 feet in the air, and the only time we ever tipped was because another robot's arm became entangled with ours and pulled us down.

Without high extensions or wedged robots this year, tipping is one of my least worries. Those teams that took advantage of the bumpers will be in even better shape with an extra 10-15 lbs. on the bottom of their robot.

Our team hasn't experienced any problems with getting poof balls caught underneath us, but that will be an individual issue depending on what your robot's ground clearance is. Poof balls under a robot "bouncing it" onto its side would be the only way I see teams getting tipped UNLESS they go for the ramp.

Mullen
02-25-2006, 06:00 PM
As one of the technical mentors showed me (as I was screaming at him), it would take a pretty good fall for us not to be able to get back up. I think that they have so much weight in the front that it just pops back up again.


Quick explanation for beth's comment, as i was the one ignoring her screams:
i was able to tip our robot so that the highest most point was about 1ft from the ground
as we stand now our robot (http://www.chiefdelphi.com/forums/pictures.php?&action=single&picid=13062) is only 68 pounds (we will be adding more) but of those 68 pounds, 65 of them are within 9 inches of the ground because the rest is just a hopper. we also plan on adding an extra 50 to the chasis at the competition, as well as battery and bumpers. So in the end, we should have about 140/145 pounds within 1ft from the ground spread out through the entire chasis
needless to say, with such a low CoG, we shouldnt have any tipping issues with our bot

edthegeek
02-25-2006, 06:11 PM
Our robot had a small problem of tipping coming off the ramp due to a higher-than-wished CG. We solved the problem by writing a ramp unmount procedure and by adding several pounds to the front (we were underweight by like 9 pounds.)

Joe J.
02-25-2006, 07:18 PM
We currently don't have anything to prevent tipping on this years bot but we may add something at our first regional if we find out we need it.

On last year's bot we had what we called Wheelie Stilts, very simple and light weight, and no powered parts. All you need is some Aluminum Angle, String, and two bolts in the size of you choice.
Our the bottom half of our robot last year was basically a box (as many bots are this year)
What we did was:
1. Cut a piece of Aluminum Angle (to size you need), and cut about 1" of one of the legs (right or left side depending on the side you are working on) off (so you have for example 19" of true 90 degree angle and 1" of flat stock.)
2. Line up the angle so it sits around the existing frame and the 1" flat spot is up and on the side of your robot the spot you choose should be strong enough to support the weight of your robot and drill a hole in the side of your frame and another on the flat part of the Al angle.
3. Put a bolt through both holes (line the with a washer in between them put a nut on and tighten it (leave it lose enough so the angle can pivot).
4. Test lean your robot back (simulate a flip) and the angle should swing out. Now find how far it must swing our to stop the robot from falling and right itself again.
5. Measure and cut a piece of string to stop it at that point and drill two more holes to tie the string to. Tie the string off and test lean it again to make sure. Adjust as necessary.

It does work last year at West Michigan we had our arm out and up trying to cap a corner goal, someone pushed us from behind and we fell forward against the goal. After they backed off we swung back up so fast we tipped backward and the Wheelie Stilts stopped us from falling over backward.

Pic (http://www.chiefdelphi.com/media/photos/8625) This picture isn't very good but its the best view of the stilts that we uploaded last year. The pivot point is right in the middle of the 8 you can see the string on the other side.

Hope this helps

irishninja
02-25-2006, 10:12 PM
I saw one of the scrimmage videos. In it, one team has these plates the folded agianst the robot ball container, but would open up so the balls would be able to bounce in(i'm assuming), anyway if they wer etipped over, it seems like they would be able to right themselves.

KenWittlief
02-26-2006, 12:39 AM
self righting technology? thats old stuff!

http://members.aol.com/wittlief/weeble.jpg


http://members.aol.com/wittlief/weebles.jpg

Alekat
02-26-2006, 12:57 AM
We were joking around one day about how we could just tip ourselves onto the ramp if we wanted the points at the end of the match, since we were so top heavy. Now that i think about it it wouldn't have been a bad idea, easier than raising our chassis to go up the stupid thing.

gondorf
02-26-2006, 08:09 PM
probably a very stupid idea but if you put a pneumatic cylinder on each side if the robot tipped over you could use the pneumatic to self right the bot.

i just thought of this because I remember the self righting robots on robot wars and they used pneumatics to right themselves

pyro20911d
02-28-2006, 05:24 PM
I think everyone gets it


no one
can save
themselves

spamified88
02-28-2006, 08:52 PM
can anyone think of a way to reduce the risk of tipping without redesigning the robot or adding much weight? ( our robot is at the weight limit assuming our scale is accurate but I am hoping the scale added weight to the robot that way we have room to make little add-ons come practice day)

Easy! Drive slower, and switch the jumpers on the victors powering your drive motors to coast! The coast setting really does work, because when our driver decides to stop short ( which he usually does), the robot slows down instead of coming to a jolting stop and then flip over. Though I don't think the coast setting works in reverse! :ahh:

rjp744
03-01-2006, 01:27 PM
believe me its been blazing through my mind for weeks now I was just wondering if any team took measures to correct the tipped cow situation... because quite a few of robots seem to be built taller with more top weight making them more susceptible to being tipped over

There are pros and cons to being tall. Although you are top heavy, if your shooter is up on top(60 inches) you cannot be blocked. It all depends on the strategy.

rjp744
03-01-2006, 01:29 PM
Easy! Drive slower, and switch the jumpers on the victors powering your drive motors to coast! The coast setting really does work, because when our driver decides to stop short ( which he usually does), the robot slows down instead of coming to a jolting stop and then flip over. Though I don't think the coast setting works in reverse! :ahh:

You can also try acceleration and deceleration functions in the coding. That works for both directions if done right.

jacob07
03-01-2006, 02:00 PM
You have officially jinxed us all :o :(

Zoheb N
03-01-2006, 02:20 PM
can anyone think of a way to reduce the risk of tipping without redesigning the robot or adding much weight? ( our robot is at the weight limit assuming our scale is accurate but I am hoping the scale added weight to the robot that way we have room to make little add-ons come practice day)

Well team 118 has now for the last two year built outriggers (basically pieces of PVC that come out of the robot after the start of the match to balance the robot) and they have worked fine. here is the thread with our 2006 bot http://www.chiefdelphi.com/forums/showthread.php?t=44643&highlight=robonauts

EricRobodox
03-01-2006, 02:54 PM
Our team has a low robot that is very efficient. Not even close to 5 feet tall. And we know we can be blocked by other teams, but for them to block us is very hard to do. If they do block us, we can beat them to the side goal anyways and dump out our balls.

Anyhow, the wheelie idea seems great for a small little nuge, but in all honesty, if that wheelie bar is not long, as in when extended out is not a foot long minimum, a robot can push that thing over easily as pie on the ramp. I am just predicting, that some falling over protections may work some of the time, i highly doubt most teams that have one will not tip over at least once in competition.

Our robot was designed with trying to get everything as low as we could get it, and at the Birmingham Sectional, that mentality got us first seed, as well as won the comp. As well as being a less or about 4 feet tall.

Good, luck with designing a mechanism for tall robots. I hope someone proves me wong. I love to see what crazy cool contraptions people make to stop this without going over weight.

Barry Bonzack
03-01-2006, 02:57 PM
1604 is 54" tall. if we throw full forward and then full reverse, it gets a bit tippy. We put some lexan on the back with a hinge so if it starts to tip it will rest on the lexan long enough for the driver to throw it in reverse. If we hit the ground there is no getting back up.

Tim566
03-04-2006, 08:43 AM
after looking at VCU webcast it appears my suspicions are confirmed so I am going to push for some sort of "anti-Tipping" device at our regional.