Re: Winnovation Midwest Coast Drive
 

How hard is it to access the WAGOs on the power distribution board?

Team 234 did a presentation on their choice of belt vs chain at the championship in 2009. Here's their presentation. http://www.cyberblue234.com/document..._CHP_Forum.pdf http://www.chiefdelphi.com/media/papers/2216

Re: Winnovation Midwest Coast Drive
 

Joe, we've already compiled a list of 28 things so far to keep an eye out for, or change altogether for the next iteration of this.

And WAGO access is on the list, also thinking of more based on comments here.

Re: Winnovation Midwest Coast Drive
 

The wheels are currently hex broached through the plastic. There is a little concern that the plastic will not hold up, and if that is the case we will be making aluminum hubs.

We've never had any real problems with chain, we were just interested in some of the advantages of using belts. Some of which include weight, efficiency, and even cost. We used all Gates belts and pulleys which were donated free of cost. It is an offer that started in 2009 and you can find details about it here: http://www.chiefdelphi.com/forums/sh...ighlight=gates

As for our tensioners, the ones in the tube are a cam attached to a bolt with a roller bearing riding on the bolt. When you loosen the nut at the end of the bolt and turn the bolt then the cam presses against the bottom of the frame and it tensions the belt running inside the tube.

Here is a picture of the tensioner inside the tube:

As for the tensioner on the gearbox, It takes one bolt to tension the belt on the gearbox. The bolt just adjusts a lever arm up or down and a plastic cylinder pressed on a roller bearing tensions the belt.

Here is a picture of the gearbox tensioner:

When it comes to rules-of-thumb I'd say, from what our experience has been so far, one of the most important things is to make sure that there is proper tension.

Re: Winnovation Midwest Coast Drive
 

How are you defining "proper tension"? Is it just a feel thing or is it something measurable?

I've seen industrial definitions for chain tension which state that the chain should be able to deflect 3-5% of the span between sprockets. That definition is generally for single speed, single direction devices though. I'm not sure if it is adequate for FRC usage with the fully reversible loads with rapid speed & direction changes that FRC experiences. This method probably does work well for a belt in a tube anyway.

btw... nice work, thanks for sharing.

Re: Winnovation Midwest Coast Drive
 

Does that mean there is a vertical slot in the frame for the through bolt to move up and down on? I'm having a hard time picturing how this works.

Re: Winnovation Midwest Coast Drive
 

Yes, need to get a picture of just the bolt assembly.

A vertical slot in the tube guides the assembly up and down, as the eccentric cam washer pushes against the bottom of the tube.

The main bolt is milled to a D which the Cam washers slide onto making it as simple as twisting the bolt to tension and then locking it down.

Re: Winnovation Midwest Coast Drive
 

Is the bolt tensioner like the really cool one on the Team221 chassis rails?

Re: Winnovation Midwest Coast Drive
 

yep, where it was swiped from :p

Re: Winnovation Midwest Coast Drive
 

And 221 I'm guessing stole it from camber adjustment bolts from vehicles. My truck has the exact same bolts but about 5 times as big to adjust camber. No matter what its a great application of the cam bolts for tensioning

Re: Winnovation Midwest Coast Drive
 

http://www.chiefdelphi.com/forums/sh...ad.php?t=70473. This desgn of an 08 west coast bot looks very similar to ur design.

Re: Winnovation Midwest Coast Drive
 

West Coast Drives are very similar and extremely popular in the past few years, but every design is different in some way or another as teams and individuals eliminate different components to save weight and increase performance. And they don't look half bad either! :P

Team 254 and 968 are most famous for their West Coast Drives over the years. http://www.chiefdelphi.com/media/photos/31597

Re: Winnovation Midwest Coast Drive
 

If you spend about 5min on delphi i bet you can find alot of pictures of 6wd bases.

Ours is actually very different in the details than the one you picked, but draws lots of things from that overall style of drive.

We chose the popular criteria of 6 wheels with the center being direct driven. And having the wheels cantilevered and the frame to match.

We drew inspiration from the very proven drivetrains of 60/254/968 and added/changed things as we wished.

Re: Winnovation Midwest Coast Drive
 

I'm just simple stating a point. Nice open design with a low profile.

Re: Winnovation Midwest Coast Drive
 

Our team is currently looking a making new gear boxes similar to yours, I was wondering if u could or anyone eles could help describe to me how they work. I understand the concepts behind the shifting but I don't know what a dog gear does, or even if it's needed. Any help would be wonderful, thanks.

Re: Winnovation Midwest Coast Drive
 

I'd download the CAD models that AndyMark has posted on their site.

If you examine the models, you can see that the output shaft has a pair of gears on it, on bearings so that they are not torsionally attached to the shaft. Between these two gears is the "dog" that is torsionally attached via a hex shaped shaft. The dog has a tooth/shape pattern on it which matches a similar pattern in each gear. When the dog is pushed against a gear, they interlock, and that gear is then able to transfer torque to the shaft. The two different gears are different sizes with different ratios, so by changing which is engaged you change your reduction (and neutral would be the space between).