Wheels for drivetrain

[who716]

We are considering changing to either the FIRST wheels (http://www.andymark.com/product-p/am-0420.htm) or the Plaction wheels (http://www.andymark.com/Plaction-s/103.htm). Which of these wheels do you guys recommend or would you suggest a different type of wheel?[/quote]

We have used the first wheels in the past and we had some trouble with them they would always seem to crack and break, dont get me wrong this might not happen with your wheels this could have been caused by the way we drive or other things, the other wheels you stated i am not familar with as i dont think we hae used them.

[the man]

Hey just my 2 cents but we are using mecanums this year and have balanced on the bridge every time we were able to get it down. We have no problem with traction. We are using the 8inch wheels from andymark. I personally like them. It makes maneuvering on the bridge quite easy. Oh and we weight exactly 120 lb.

[jon-s]

Originally Posted by who716

We have used the first wheels in the past and we had some trouble with them they would always seem to crack and break

Our team went to a competition this past weekend and one of the other teams there broke one of the FIRST wheels (an entire section was missing) trying to get over the barrier.

[MrRiedemanJACC]

Cal 578, Funny you should mention the dual omni's - that is exactly what we are wondering about. We already have four omnis from years past and we are going to make our own spacer and put the chain drive down the middle of them. (we want to center the load on the "wheel" bearings). The chain drive is coming from a dual sprocket from the cimple gearbox with two cims. One chain will be to the front with dual omni's the other to the back with traction wheels (possible doubled up for more pushing - moving other teams on the bridge). We think that multiple teams balancing on the bridge will only work if one team makes the decision.

Also we are considering the KOP wheels for the front vs. the dual omnis. We are worried about getting over the bridge even with the dual omnis. We will try to get both sets made up so that we can test and see which one will work. Luckily Michigan has a 6 hour out of the bag rule just for those things... (since we have 2-day events).

Garrett, I didn't speak clearly enough - that is 2 Cim's per side of the robot, so all 4 CIM's are on the drivetrain. We have machined the cimulator from banebot to accept 2 RS-775's for our shooter.

We definitely have variable speed on the drive. It actually goes through two functions to make it more driver friendly.

Thanks for the input!

[who716]

Originally Posted by jon-s

Our team went to a competition this past weekend and one of the other teams there broke one of the FIRST wheels (an entire section was missing) trying to get over the barrier.

was one of the reason we chose not to use those wheels as we had a feeling they would break going over the beam, i guess we were right

[AllenGregoryIV]

Hey Jon,

Spectrum is using a combination of plaction and kit wheels this year because we find that the plaction wheels have very poor traction on the bridge (lexan) and the the key (HDPE). The plaction wheels however are great on the carpet because they can interlock with it.

I would consider using plaction on your front wheels and kit wheels in the rear, that way you can climb the bridge backwards and keep traction on the bridge the whole time. You will also probably still be able to get into your preferred shooting position touching the driver station wall and the barrier ("checkmate shooting") because your kit wheels will slip a bit easier sideways than having all plaction wheels.

If possible I would also chain the two wheels on each side together to make sure all of your power is transferred to the ground no matter which subset of your wheels are in contact with the ground.

I did see that Shadetree Mechanics (3999) broke a kit wheel but that was an extremely tough impact on the barrier, most teams should really slow down before they climb, teams like 16 are rare that can climb the barrier at high speeds.

PM me and we can talk more about this problem.