Team 1565 Unique Drive System

[vhcook]

That's the most amazing thing I've seen all week. It's a thing of beauty.

[Deep Dark]

As i'm watching the video, i'm thinking:

wouldnt it be cool if the wheels all rotated half way (45 degrees), then all the wheels are 90 degrees to each other and it becomes holonomic drive....

but....yeah. totally unnecessary. Definately a sweet looking system. Congrats! i'm impressed!

[T3_1565]

Originally Posted by Deep Dark

As i'm watching the video, i'm thinking:

wouldnt it be cool if the wheels all rotated half way (45 degrees), then all the wheels are 90 degrees to each other and it becomes holonomic drive....

but....yeah. totally unnecessary. Definately a sweet looking system. Congrats! i'm impressed!

funny story about that.. They did. We had a three stage so we can drive in omni for standard avoiding robots, but programming it turned out harder than we thought, and because nothing else on our bot needs air, we decided to just go for the two stages

[abeD]

Wow impressive, definitely gets my vote for creativity.

Couple of questions:

What made you choose this design over a crab style with 1 motor controlling wheel orientation?

Are you worried about getting pushed (on purpose, or inadvertently) having all omniwheels?

[T3_1565]

Could the 1.5" bore piston be replaced with 2 separate 3/4" bore pistons that are identically mounted but move in opposite directions to achieve the same effect?

You can use 1 3/4" bore if you wanted, but we only had a 1.5" at the time, and decided why bother replacing it if we already have a mount made for it.

Can the omnis be replace with traction wheels for more traction or is there too much skid when the wheels orthogonally rotate 90 degrees while the robot is at speed?

No the omnis cannot be replaced, nor have we tried, because of the skidding it does, when switching the wheels at speed. It would seem to me (which is why we didn't try) that the linkage would probably destroy itself if traction wheels were on it.

What made you choose this design over a crab style with 1 motor controlling wheel orientation?

We wanted to do something unique, and we have no experience with crab or omni for that matter. We decided to make an in-between bot that was easier to build than crab, yet stronger than omni

Are you worried about getting pushed (on purpose, or inadvertently) having all omniwheels?

No we aren't, if someone pushes us, the only way we would move easily is if pushed perpendicular to the wheels (so along the rollers) in which case, we can switch the wheels. Omni wheels are good for traction when being pushed striaght with the wheels. Overall we should have as much pushing power as any four wheel drive bot, from every direction.


Thanks for the comments everyone!!

[MrForbes]

This is an amazing robot, great job!

Originally Posted by T3_1565

Overall we should have as much pushing power as any four wheel drive bot, from every direction.

I wouldn't go quite that far....keep in mind that when you push up against another robot, much of the weight is transferred to the rear wheels, and you only have two drive motors back there. A normal skid steer 4 wheel drive bot has power to both front and rear wheels on each side from a common transmission, so it has twice the torque available at the rear wheels as yours does.

But this years game seems to be more conducive to quick, highly maneuverable robots like yours, so that should not concern you.

[T3_1565]

well for generalization sake, we are a four wheel drive bot, with omni bot agility (again roughly)

thanks again for the comments!

[DarkFlame145]

that is really cool, it looks like a solid drive train

[gblake]

Good Job - I was thinking of building something similar out of Vex equipment. Now I think I'll have to.

Because I'm lazy , will you be able to send me (after the build season perhaps) your algorithms for converting operator inputs into wheel turns and motor spin directions?

What are your operator/driver's controls? Joysticks? Knobs and sliders? Something else?

Does the machine rely on a gyro or a similar device to know which way is pointing (and then combine that info with the operator's inputs when deciding how to point and spin the wheels)?

Blake

[T3_1565]

Originally Posted by 1885.Blake

What are your operator/driver's controls? Joysticks? Knobs and sliders? Something else?

Does the machine rely on a gyro or a similar device to know which way is pointing (and then combine that info with the operator's inputs when deciding how to point and spin the wheels)?

Blake

Well to tell the truth, the system is really easy, its driven with an xbox 360 controller, like any normal 4 wheel drive, and the "A" and "B" button switch modes, once the modes are switched the program knows what setup it is in (based on what button is pushed) and switchs drive codes accordingly, no gyro, nothing special on it at all. Just designed very well (not to toot my own horn )

[Team56]

That looks very cool.. I love the way where you guys don't have to turn, just switch the wheels =)


www.team56.com