So how many of you actually have a working minibot/deployment?

[Saber Robotics]

I apologize for seeming like we just want answers. Truth is we are down right scared to start digging around in the motors, this close to competition. We fear that our minibot is decent, at around 4.5 seconds not including deployment, and we were wondering what a good way to go about it is.

Sometimes we need to figure stuff out on our own and other times we dont have the knowledge to know what to do. So here is my updated question, what are some different ways that teams have modified the gearboxes on their tetrix motors. Are there available gears for purchase or is there a way to manufacture your own?

Again sorry that I misspoke and thanks for the help.

Originally Posted by Saber Robotics

I apologize for seeming like we just want answers. Truth is we are down right scared to start digging around in the motors, this close to competition. We fear that our minibot is decent, at around 4.5 seconds not including deployment, and we were wondering what a good way to go about it is.

Sometimes we need to figure stuff out on our own and other times we dont have the knowledge to know what to do. So here is my updated question, what are some different ways that teams have modified the gearboxes on their tetrix motors. Are there available gears for purchase or is there a way to manufacture your own?

Again sorry that I misspoke and thanks for the help.

I was on another forum pagem and someone said this one quote, "Some teams are still working on their robots, some refuse to improve. Improve or perish". We are working on our minibot and the deployment system, and will continue to work on it until March 31st (competition day). You can see our robot in this video: http://wghsrobotics.webs.com/apps/vi...4-rampage-2011 I made the video, and the website, all by myself! . Our minibot is at the very end. It goes up in less than 4.3 seconds, but we're still working on deployment and the speed of the minibot.

[boomergeek]

Buy more TETRIX motors.

We ordered two before we got the FIRST choice package.

I'm going to lobby to buy more.

If you have one working minibot in hand, I would advise you leave it alone until you have a second better working minbot in hand- Only after you reached that point should you consider cannibalizing the first minbot.

Yes, it's $40-60 for the motors depending on your school discount- but it is a huge stress reliever to have that working bot locked up safely while you experiment (especially if you are considering destructively ripping into the gearboxes)

[JosephC]

We got our Minibot up the pole in 3.14 seconds(not including deployment). We're also working on another minibot that's about half way done that should double our speed (to like 1.7 seconds). Our delivery system should be done tomorrow and "should" take 1 seconds to deploy but we'll see

[DonRotolo]

Originally Posted by Saber Robotics

Truth is we are down right scared to start digging around in the motors, this close to competition.

Get more motors. Break them instead of your 4 second minibot. You can't learn anything without breaking some stuff.

Inside you'll find four gears. Most of them match up with the others easily - that is, they (almost) all have the same "pitch". So, no need to buy more gears.

Play around with them for a while, figure out the output gear ratios for different combinations that can work, and write them down. (Note that the 'height' of the gears might not be right, sometimes you need to make spacers for the gears to get them the right height. The gear on the output shaft might need to be pressed off and you'll have to figure out how to hold it on at a different spot)

Then do the same for the tetrix gears and wheel combinations, then calculate the 'motor to wheel' gear ratios.

Pick a bunch of them - one at each end, a couple in the middle - to try out, see which works best. Keep careful notes of everything you do. Once you have the 'best', try more ratios that are closer to the 'best', and find the 'new best'. repeat until you have the best of the best, and build your minibot.

Does this process make sense to you? Of course, you need to do perhaps ten of these 'experiments' a day. Try to keep the weight of the frame of the minibot the same, make a switch system to start and stop it automatically, use a fresh battery every 4-5 runs, all to eliminate any variables that could fool you.

Good Luck.

[Nelson]

Our team has a working minibot, although It will probably change a lot between now and the Utah Regionals.

Originally Posted by Nelson

Our team has a working minibot, although It will probably change a lot between now and the Utah Regionals.

I believe EVERYONE'S minibots will change between now and their regionals!

[Nelson]

It gives a lot of work to keep us busy, which is what we all need.

Originally Posted by Nelson

It gives a lot of work to keep us busy, which is what we all need.

Exactly!

[Saber Robotics]

Originally Posted by DonRotolo

Get more motors. Break them instead of your 4 second minibot. You can't learn anything without breaking some stuff.

Inside you'll find four gears. Most of them match up with the others easily - that is, they (almost) all have the same "pitch". So, no need to buy more gears.

Play around with them for a while, figure out the output gear ratios for different combinations that can work, and write them down. (Note that the 'height' of the gears might not be right, sometimes you need to make spacers for the gears to get them the right height. The gear on the output shaft might need to be pressed off and you'll have to figure out how to hold it on at a different spot)

Then do the same for the tetrix gears and wheel combinations, then calculate the 'motor to wheel' gear ratios.

Pick a bunch of them - one at each end, a couple in the middle - to try out, see which works best. Keep careful notes of everything you do. Once you have the 'best', try more ratios that are closer to the 'best', and find the 'new best'. repeat until you have the best of the best, and build your minibot.

Does this process make sense to you? Of course, you need to do perhaps ten of these 'experiments' a day. Try to keep the weight of the frame of the minibot the same, make a switch system to start and stop it automatically, use a fresh battery every 4-5 runs, all to eliminate any variables that could fool you.

Good Luck.

Now that helps a lot! Thanks so much and I believe in my minibot team to figure it out.