which holonomic drivetrain do YOU think is the best any why???

[NyCityKId]

this is a poll between crab drive/swerve drive, mecanum drive, and omni drive (small wheels are perpendicular to main wheel). feel free to list any other holonomic drive u might know about or prefer.

also feel free to IM me

[BrendanB]

No poll.

EDIT: Didn't know if you knew it wasn't there. Thanks!

[NyCityKId]

Originally Posted by BrendanB

No poll.

the poll is up now .... i had to post the thread before i put up the poll... sorry

[Daniel_LaFleur]

Kiwi

[NyCityKId]

Originally Posted by Daniel_LaFleur

Kiwi

why???

[thefro526]

Asking which one is best is a bit difficult because there are many factors involved like, Cost, Build Difficulty, Programming, Control, etc...

Personally, the only type of Omni-Drive I would consider is a Swerve. The upside to a swerve drive is that you have full traction, which is something that Holonomics and Mecanums lack. The downside to a swerve is that it's difficult to build and can be a pain to program and drive.

[NyCityKId]

Originally Posted by thefro526

Asking which one is best is a bit difficult because there are many factors involved like, Cost, Build Difficulty, Programming, Control, etc...

Personally, the only type of Omni-Drive I would consider is a Swerve. The upside to a swerve drive is that you have full traction, which is something that Holonomics and Mecanums lack. The downside to a swerve is that it's difficult to build and can be a pain to program and drive.

well stated.... point taken

[MarkoRamius1086]

Originally Posted by thefro526

Asking which one is best is a bit difficult because there are many factors involved like, Cost, Build Difficulty, Programming, Control, etc...

Personally, the only type of Omni-Drive I would consider is a Swerve. The upside to a swerve drive is that you have full traction, which is something that Holonomics and Mecanums lack. The downside to a swerve is that it's difficult to build and can be a pain to program and drive.

You took the words right out of my mouth!

[Jon Stratis]

I would say it's highly dependent on the task.

There are complexities with crab/swerve that aren't present in the others - with a short build season like we have, it may be too complex to accomplish (when you consider everything else you want to accomplish). Then again, they provide more pushing power in any direction than the others - is pushing power important enough to accept the additional risks that come with the complexity of crab/swerve? Do you have the weight available for crab/swerve (as it is typically heavier than other drive systems)?

Having Mecanum wheels on the corners works great, so does having omni wheels on each of the 4 sides. But if you need to go up a ramp, an omni wheel setup like that isn't going to work, while mecanum will. And just taking the omni's at 45 degrees to the frame in the corners is basically mecanum, only with the added complexity of needing to mount everything at 45 degrees to the frame.

So before you can really get good answers, you have to define the task and the associated parameters. Each system is good, but different systems will excel at different tasks and with different parameters. One of the key challenges with building a robot for FIRST isn't identifying a single "best" system and perfecting it to use year after year. It's in identifying what the best system would be for a given task and working in a very short time period to perfect it.

[NyCityKId]

Originally Posted by eagle33199

I would say it's highly dependent on the task.

There are complexities with crab/swerve that aren't present in the others - with a short build season like we have, it may be too complex to accomplish (when you consider everything else you want to accomplish). Then again, they provide more pushing power in any direction than the others - is pushing power important enough to accept the additional risks that come with the complexity of crab/swerve? Do you have the weight available for crab/swerve (as it is typically heavier than other drive systems)?

Having Mecanum wheels on the corners works great, so does having omni wheels on each of the 4 sides. But if you need to go up a ramp, an omni wheel setup like that isn't going to work, while mecanum will. And just taking the omni's at 45 degrees to the frame in the corners is basically mecanum, only with the added complexity of needing to mount everything at 45 degrees to the frame.

So before you can really get good answers, you have to define the task and the associated parameters. Each system is good, but different systems will excel at different tasks and with different parameters. One of the key challenges with building a robot for FIRST isn't identifying a single "best" system and perfecting it to use year after year. It's in identifying what the best system would be for a given task and working in a very short time period to perfect it.

point taken. the question and poll was meant to see what people thought the best drive train was in GENERAL. in other words, what drivetrain is the most adaptable to any situation? no system is going to be perfect and most teams will definatly realize the need to change strategies year after year. i also didn't want to limit this discussion in any way. i left it up to responders to give a situation and then give an opinion. FIRST is so dynamic that giving one specific situation is just as bad as giving none, no?

[Foster]

I think that a 360 degree with all four pivots turn independently moving swerve drive is best since that's what we are driving this year.

But I have to give very high marks to the omni/twitch hybrid I saw at Philadelphia. (Sorry I've spazzed on remembering your team number/name).

Each corner was a pair of Andy-Mark Omni's bolted together so that there was a continuous set of rollers around the circumference. They were set up in a standard 4 motor drive.

Two opposite corners were mounted on Delrin pivots. The wheels could be turned 90 degrees by two small pneumatics.

Best of both worlds: tank drive with good forward / backwards grip but a little slip to allow easy turning and the ability to flip into a omni-bot for strafing and translation movements.

A very clever solution to allow omni-bot flexibility with a low center of gravity and clearing the humps.

[thefro526]

Originally Posted by Foster

I think that a 360 degree with all four pivots turn independently moving swerve drive is best since that's what we are driving this year.

But I have to give very high marks to the omni/twitch hybrid I saw at Philadelphia. (Sorry I've spazzed on remembering your team number/name).

Each corner was a pair of Andy-Mark Omni's bolted together so that there was a continuous set of rollers around the circumference. They were set up in a standard 4 motor drive.

Two opposite corners were mounted on Delrin pivots. The wheels could be turned 90 degrees by two small pneumatics.

Best of both worlds: tank drive with good forward / backwards grip but a little slip to allow easy turning and the ability to flip into a omni-bot for strafing and translation movements.

A very clever solution to allow omni-bot flexibility with a low center of gravity and clearing the humps.

You're talking about 1218, I believe they won and award for their drive.

[Alan Anderson]

Best for what?

(I don't consider swerve drive holonomic.)

[EricH]

1) What are the requirements of the game?
2) What can you build and program in the 6 weeks?

If the drive you choose fits both, it is the best.

If I had to choose, I'd go with mecanum, because it's relatively easy to swap out the mecanums for some standard wheels and spacers. Swerve, you have to lock the modules (depending somewhat on what arrangement you have).

BTW, Kiwi Drive is 3 omni wheels arranged in a triangle.

[ALTrammell818]

Mecanum drive has proved quit useful to us this year.