pic: Team 2404 (TNT) Omni Drive System

[LaurenH]

loading photo ...

[T3_1565]

Thats a pretty crazy design!!! Any reason why you didn't do a standard omni system?? It seems like you strafing abilities are going to be much slower than your foreward and backward. And it also seems to cost alot more than a standard omni drive system.


What made you decide this?? It is very neat!!

[diesel]

I can see why you built the omni drive this way.
Most of the game is driving forward, not much 'straffing' has to be done.
The four wheels in the regular position will help more than just two driving forward.

My concern, which you probably thought about.
-If you are on the bump a 'straffing' wheel might not be on the ground, and the robot would just spin.

Are there little 'shocks' on the wheels??

[jax1488]

chain tension?

[GaryVoshol]

Wheels aside, I presume the C-channel things sticking up on all 4 sides are for bumper attachments? You would have a bolt of some form that comes out of the bumper and fits the slot on the channel, and then is tightened down.

My question is if you've checked the size of the frame. The channel adds a bit of width I think (can't tell for sure, but it looks wider than the end pieces of the kit frame). Beside that, there are bolt heads sticking out. A kit frame doesn't give you much leeway with the 28 inches - 3/8 or 5/8" as I recall. Check if you'll still fit in the box.

[Jim Meyer]

We talked pretty extensively about a drive system just like this for this year. In the end we chose a different direction, but I'm anxious to see how it works for you.

T3, what do you mean by a "standard" omni system? Are you referring to the holomonics?

[vivek16]

Wow, this was almost exactly our setup! Will you be coming to the Minneapolis regional? We have the same omni wheel setup. But, each side is powered by a CIM motor in our design.

Hoping to see more, Vivek

[LaurenH]

Last night after its first test run, we talked about adding shocks to the 5th and 6th wheel. Do you have any suggestions for shocks? Is there anything to watch out for?

Currently, we know that the four standard wheels (forward/backward driving) work excellent, so if the 5th and 6th wheels need to be remove it would not cause a functional problem. These wheels are for strafing which we would like to have for strategy and alignment purposes. In all truth we should have used mecanum drive system, but either one of these drive systems will achieve basically the same thing.

jax1488 - I’m not sure what kind of question you have about chain tension. The gearboxes are slotted and use to tight one chain, while we use a free spinning sprocket (as seen to the left of the gearbox) to tension the other chain.

GaryVoshol - Yes, the C-channel is for the bumper mounts and yes the bolts will be designed into the bumpers so that they will slide on and quickly tighten in place. We are approximately 26.5 x 36 inches as we cut our chassis for leeway.

As soon as we get the 5th and 6th wheel touching the ground properly, we’ll post a video (if anyone is interest I can also post a video of my other teams (FTC 25) 8 wheel omni drive system where one set of four wheels are used for speed while the second set was used for torque – it was amazing and work better than we ever taught it would).

vivek16 - I would love to see pictures. Currently we are only registered for the LA regional. Now that the teachers and students have been bit by the FIRST bug, everyone is hoping to earn a spot in Atlanta.

Thanks for all the comments.

[ay2b]

Nice job! When do we get to see the videos?

[T3_1565]

Originally Posted by Jim Meyer

T3, what do you mean by a "standard" omni system? Are you referring to the holomonics?

I definatly was referring to holonomic lol sorry for the confusion

[team1203 4life]

that was intresting how you guys used t a set of wheels on the front and back good luck

[LaurenH]

Any suggestions for adding shocks? How have you gone about it? Overall the drive system works, but a shock system would help quite a bit. We also bought 8" Mecanum wheels last night, just in case we feel like a new challenge.

[LaurenH]

Diagonal driving, strafing, and zero point turns:
http://www.youtube.com/watch?v=JqJK0E9Jpmk

Driving in an arch:
http://www.youtube.com/watch?v=b8jtsSxePME

First time driving the 6 wheel omni drive system (get an idea of the acceleration):
http://youtube.com/watch?v=pZf1-6wyOgA

Currently our best lap time was 13 seconds.

Prototype work:
Launch the ball over the overpass and lane divider:
http://youtube.com/watch?v=cUI9pu7VLD8&feature=related

Knocking the ball off the overpass:
http://youtube.com/watch?v=JsE634kwVSQ&feature=related