2008 and drivetrains

[abeD]

Yea my team in 2003 had 2 steered casters in the front with a 4 wheel drive in the back, it worked pretty well but there were a couple of things i would have changed, and yes you could really fly while turning which was pretty cool.

I can also remember several teams that have employed some kind of steering, obviously all the crab drives, but 16 baxter bomb squad a couple years ago had a tricycle setup with all 3 wheels driven and 1 steered, worked very well from what I remember.

[burkey_turkey]

Originally Posted by lukevanoort

What good is a omnidirectional design if your drivers don't know how to use it?

Heh, this is EXACTLY what happened to us last year - we couldn't drive our own robot! Loks like we're gonna be doing two powered wheels in front, two powered omnis in the back, tank drive, so we can 'drift' around the corners.

[tdlrali]

Before you lock on that drive, think hard about the 'drift'... it wont be pleasant.

[Ed Sparks]

I really think a well designed Ackerman system is the way to go.

I'm lobbying my teammates for:
- Ackermann
- Rack & Pinion Steering
- 2 Speed Single Power Plant
- Limited slip differential

I already have a differential design that is fairly easy to make (I'm currently working on reducing the weight a little) and I like the AM SuperShifter. We're looking at various RC car designs for some practical solutions.

[Neil B]

I don't know. If you're going to go Ackerman you'd better have a good turning radius and some good programming for your controllers. It seems to me that there is a lot of space open on the field (each lane is 13 feet wide) but I also think that there's going to be a lot of robot crowding, especially when robots are extended. It seems to me that Ackerman would be difficult to steer precisely when it's on the opposite side of the field; especially with trackballs that are so big they could potentially completely block the view of your robot. The other issue I forsee is a difficulty in turning around unless you intend to be using reverse (another adventure in steering with Ackerman). I'm not saying it can't be done but it will take a lot of practice for the drivers to get good and precise with their steering considering they have a fixed point of reference instead of one on the object (like in a car).

In either case, it will be very interesting to see what drive trains everyone is using. We're thinking of a 6-wheel drive for this year; power when you need it, maneuverability when you need it.

[Ed Sparks]

Originally Posted by Neil B

I don't know. If you're going to go Ackerman you'd better have a good turning radius and some good programming for your controllers.......

Programming should be fairly simple, a pid loop to control steering angle and the Y-Axis direct to the powerplant (ok maybe a rate limiter). I don't see the complexity. Am I missing something?