254 Presents: Cheesy Poof Build Blogs

[NickE]

For the last two seasons, Team 254 and our collaboration partners have been keeping blogs of our prototyping, manufacturing and build progress. We update these blogs daily, splitting the responsibility among multiple team members and try to include lots of pictures and videos. The blogs serve multiple purposes, keeping team members, parents, collaboration partners and sponsors up to date on build progress while also allowing us to document our build process.

2011 Team 254 Blog
2010 Team 254/968 Collaboration Blog

Wow. That's just amazing. This is like a look at your build season! I can see why you guys won this year!

[rcmolloy]

Originally Posted by SuperNerd256

Wow. That's just amazing. This is like a look at your build season! I can see why you guys won this year!

I want a champions shirt so bad. Give me now!

[BrendanB]

Thanks so much for sharing this! It has been a great read!

[114Klutz]

Was this public during the build season?

[NickE]

Originally Posted by 114Klutz

Was this public during the build season?

No

[davidthefat]

This explains a lot... Your team seems to have been going a lot faster than our team as far as progress during the season is concerned. Drivers actually had time to practice; I was literally given the controls of the arm during the competition. And your robot was actually finished before shipping; we had to install the arm during the competition. We did not even use it at San Diego; I just never had the go ahead to use it because we were doing fine without it. I had not installed the software updates until literally week 3 or 4; you guys did it on day one. Your electronics were clean and organized; ours was a pile of mess, which was a major part of our downfall at LA. I applaud you guys.

[AlecMataloni]

Get me one of those shirts at IRI and I will love your team even more (if that's even possible).

[Cory]

If you read the 2010 blog in it's entirety you'll notice that on day 2 of build we were testing a 8wd drivebase on the bumps.

This was something we were very proud of and thought was very cool. With about 6-8 hours of work we were able to manufacture frame rails and bolt together a frame to accommodate 8 wheels. We were then able to raid our spare parts bins for bearing housings, wheel shafts, sprockets, tensioner cams, gearboxes from the 08 robot, and 4" wheels.

We spent a lot of time prior to that diagramming out the interference between the bump and frame with various wheel sizes and configurations. We were very concerned about making a decision without empirical evidence that it would work, so being able to do this was invaluable.

At a few points we have considered moving away from a 7/16" hex on the wheel side of the shafts and a 1/2" hex on the sprocket side in favor of using hex bearings and a straight hex shaft all the way through. Every time we've shot it down because it makes everything we've made since 2006 incompatible with any future parts.

Having that supply of parts that has remained functionally (if not perfectly) identical and interchangeable since 2006 allowed us the flexibility to throw together an entire drivebase in under a day and test something critical to the design of our robot. This offers a huge advantage if you have the foresight to keep families of parts common.

[lemiant]

Thank you! I read them all, they were very informative.

[Chris is me]

This is so insightful. No "magic", just hard, hard work.

[topgun]

On the January 9th page, you posted your final drivetrain speed. When I run those calculations through the JVN calculator I only get 100% efficient speeds of 18.92 ft/sec and 6.81 ft/sec, whereas the blog posting shows 19.8 ft/sec and 7.1 ft/sec.

What would explain the difference?

I used CIMs at 5310 rpm free speed and the gearing showed on the blog posting.

Thanks.

[JesseK]

Originally Posted by Cory

At a few points we have considered moving away from a 7/16" hex on the wheel side of the shafts and a 1/2" hex on the sprocket side in favor of using hex bearings and a straight hex shaft all the way through. Every time we've shot it down because it makes everything we've made since 2006 incompatible with any future parts.

Having that supply of parts that has remained functionally (if not perfectly) identical and interchangeable since 2006 allowed us the flexibility to throw together an entire drivebase in under a day and test something critical to the design of our robot. This offers a huge advantage if you have the foresight to keep families of parts common.

This is an incredibly huge insight for anyone that it's new to. This is typically how industry moves. Why did XYZ make that inane decision in their latest iteration of product instead of using a blanket 'best practice'? In any complex integrated system (robot, submarine, satellite, cars) it's usually for backwards-compatibility.

[NickE]

Originally Posted by topgun

On the January 9th page, you posted your final drivetrain speed. When I run those calculations through the JVN calculator I only get 100% efficient speeds of 18.92 ft/sec and 6.81 ft/sec, whereas the blog posting shows 19.8 ft/sec and 7.1 ft/sec.

What would explain the difference?

I used CIMs at 5310 rpm free speed and the gearing showed on the blog posting.

Thanks.

We used 5550 rpm free speed. Our measured efficiency on the bench ended up being 90-95% with a free speed of about 18.5 ft/sec with no weight on the wheels.

[JVN]

BIG Kudos and BIG Thanks to 254 for sharing!
I really appreciate getting a glimpse into your world class program and the building of your BEAUTIFUL machines.

Keep up the fantastic work.

Thanks again!
-John