As of today, January 15th, we have most of our chassis completed. We are using the Andy Mark one speed gearboxes (http://www.andymark.biz/am-0011.html) and 4 CIMs to drive it, also we are once again using the 6" NPC wheels (http://www.npcrobotics.com/products/viewprod.asp?prod=47&cat=22&mode=gfx). See you all at Philly and the Championship event.
What size 80/20 (or Bosch) is this? Looks very nice! Good work!
nate: we’re using 1"x1" 80/20.
What made you decide to go with a 4WD instead of a 6WD like last year?
Luke: Why we decided not to got with a 6 wheel drive like last year is because of a few reasons. One being that there is no guaranteed ramp at the end of each match, however the most influential one was the fact that our method for a 6 wheel drive last year was very finicky. The tensions of all the chains we interdependent, so if the front most was too tight, the rear most was too loose, and vise versa. Using just 4 allows us an easier way to adjust the chains and have a lighter drive base that is just as powerful. Also, if we do eventually need to add 2 more wheels to our bot for some reason, we can just slide the bearings into place easily.
i c that u guys used the gear box from last year… is that legel?
That’s not the same gearbox–it’s an AM Gearbox from AndyMark, which is similar (but not the same).
Indeed. It runs quieter than the 2006 kit gearbox and has some other differences as well
i bet it runs quieter! the 2006 kit gearbox was loud as heck, even after we removed the crushed metal bits. i miss the old gearbox though - have you found the andymark one to be as robust? i feel like the banebots planetaries are a little wimpy compared to last year’s box.
If you are removing center wheels from a 6-wheel design, then make sure your 'bot will be able to turn. Basic rule of thumb: If the distance between wheels side to side is greater than the distance between wheels front to back, then you are OK. If not… consider a change.
I miss 80/20. The team I’m mentoring doesn’t use it.
They seem to run nicely on our bench tests, however I can give you a better idea after we start driving the bot around sometime this week.
With the top row of extrusion, electronics, and chain, this will weigh 58 lbs.
I think it’ll work, but we’ll see tomorrow. If we have to, we can exchange wheels for casters.
We don’t quite meet the rule of thumb (side to side is about 23", front to back is about 27"), but we did more than simply reorient and remove two wheels. Our sprockets/ratios are different, our gearbox went from the 2006 kitbox to the AM single speed and is repositioned, the way we chain/connect has been revised, etc). Since week two we’ve been testing on carpet at 120+ lbs and are doing fine.
We’re still running fine with the setup and the AM singles seem plenty robust in our testing. While this isn’t on carpet and isn’t with our extra weight (ramp/platform to come), this should give you a little idea of where we are… http://video.google.com/videoplay?docid=-8316004237025530860&q=FRC+1712
We’ll shoot some more video on carpet in more space next week to show those that are interested in the AM single speed.