Team 254 Presents: 2013 Build Blog
 

During the 2013 season, as in the past several, Team 254 tracked its prototyping, manufacturing, and build progress using an internal blog. The blog makes sure our team members, parents, and sponsors are kept up to date on our progress as it happens, and also provides us with documentation of our build season for posterity. We have spent the last few weeks polishing it and are pleased to be able to share it publicly now.

2013 Build Blog: http://2013.team254.com/category/frc/2013/

Re: Team 254 Presents: 2013 Build Blog
 

Between this and 1538's build blog, I'm going to have a hard time focusing on classes this week.

Thanks again Poofs!

Re: Team 254 Presents: 2013 Build Blog
 

I can't navigate beyond day 11.

Very cool stuff though!

EDIT: Still having the problem. You can get around it by navigating to http://2013.team254.com/category/frc/2013/page/2/ though.

Re: Team 254 Presents: 2013 Build Blog
 

Same

Re: Team 254 Presents: 2013 Build Blog
 

It's like FIRSTmas came early!

Re: Team 254 Presents: 2013 Build Blog
 

Nice cookie recipe!

Re: Team 254 Presents: 2013 Build Blog
 

I was supposed to finish my summer reading this weekend...

Re: Team 254 Presents: 2013 Build Blog
 

It's okay, because it doesn't seem to load past day 11 at this point. But up until then, it was a solid read.

- Sunny G.

Re: Team 254 Presents: 2013 Build Blog
 

It's working for me until April 19th - Pre-STL Day 9.

Just to make sure, did you press "Next Page" :D ?

EDIT: With Internet Explorer, the blog seems to be split into pages. With Chrome, the blog is one continuous page. Haven't checked with Firefox.

Re: Team 254 Presents: 2013 Build Blog
 

Page 2
Page 3
Page 4
Page 5
Page 6

Re: Team 254 Presents: 2013 Build Blog
 

No design iterations for the hanger? Where did the practice field come from?

Re: Team 254 Presents: 2013 Build Blog
 

Right, except that it's apparently not visible past day 11 on FF and Chrome. Or at least, that's how it is for me. I suppose I'll just jump to IE. *sigh*

- Sunny G.

Re: Team 254 Presents: 2013 Build Blog
 

Great job documenting everything that went into the season build and competitions! Thoroughly enjoyed the details and the videos...so much of the process was just like ours (including the problems that arose and the process to fix them). Thanks again for partnering with us at San Diego!

Re: Team 254 Presents: 2013 Build Blog
 

It's working with the latest version of Google Chrome, for me at least.

Re: Team 254 Presents: 2013 Build Blog
 

Most of the hanger iteration happened between San Diego and SVR, when the blog's coverage is more spotty.

Re: Team 254 Presents: 2013 Build Blog
 

One of the things that impressed me reading through this was how much care and effort was put into manufacturing prototypes-- 254's prototypes (from the videos) looked nicer and worked better than most of my team's finished mechanisms! Excuse me while I learn again why 254 is a world-class team.

This was a real treat to read.

Re: Team 254 Presents: 2013 Build Blog
 

"Lab closing time for the night was… 11:30 AM (Yes, AM)"

Apparently you folks put in some late nights and early mornings this past season.

These blogs are absolutely fascinating. It's great to see inside the Cheesy Poofs' shop and get a look at just how organized and hard working the team is.

Re: Team 254 Presents: 2013 Build Blog
 

WOW. Just simply, wow.

That was a great read! It's on the list of things to do prior to kickoff.

Re: Team 254 Presents: 2013 Build Blog
 

The scrolling issues have been fixed. Sorry about that.

Re: Team 254 Presents: 2013 Build Blog
 

I'm interested in some more details regarding the encoders on the drivetrain. They look to be US Digital S4 encoders, however I don't see a mount for the body, how are they mounted to the frame?

Kelly

Re: Team 254 Presents: 2013 Build Blog
 

As far as I know many west coast teams drill a hole into the drive shaft, push the encoder into the hole, and then zip tie the wire to the belly pan. No mount is needed.

Re: Team 254 Presents: 2013 Build Blog
 

It's how we did it for our offseason robot. It's great. The only word of caution is to make sure you've got a good fit between the hole and the encoder shaft. If its too loose, it will easily fall out. If its too tight, you'll bend the shaft when trying to insert it. We marred up the encoder shafts using vise grips to make it easier to get a nice press fit.

Re: Team 254 Presents: 2013 Build Blog
 

Correct, we do this almost everywhere.

Sometimes we use a standoff as a post next to the encoder body to make it easier to lock torsionally.

Re: Team 254 Presents: 2013 Build Blog
 

So if I'm understanding this correctly, the encoder is just floating or resting on something?

Re: Team 254 Presents: 2013 Build Blog
 

It's generally just floating, with whatever's holding onto the wire (typically a ziptie) providing the tiny amount of force needed to keep the encoder from spinning with the axle.

The idea behind this is to not mechanically over-constrain the encoder, as rigidly mounting the encoder as well as pressing its shaft into the axle would do.

Re: Team 254 Presents: 2013 Build Blog
 

Do you guys have any pictures of said West Side sorcery? We East Side folks be wondering. ;)

Re: Team 254 Presents: 2013 Build Blog
 

You can sort of see it here. Look at the last picture in the original post. There's no mount. The bore for the encoder is a tight fit (just under press fit) and the encoder wire is zip tied to the baseplate.

Re: Team 254 Presents: 2013 Build Blog
 

Re: Team 254 Presents: 2013 Build Blog
 

That looks mighty...sketchy. I suppose the fact that so many people use this method speaks to its validity, but doesn't the encoder want to spin with the axle? While I expect that the zipped down wires help some of that, I can't help but think that there's a little wiggle in there.

- Sunny G.

Re: Team 254 Presents: 2013 Build Blog
 

Even if it does wiggle, it really can't wiggle enough to mess up 15 seconds of driving.

Re: Team 254 Presents: 2013 Build Blog
 

These are the ball bearing S4 encoders. This will not work with the bushing ones. We do not use the bushing ones anywhere. We typically hot glue the connector and add additional strain relief to the wire to prevent damage to the wire/connector. If done properly there is no "wiggle" as the bearing drag is the only friction that exists and is quite minimal. We have done this (on 254/968) for as long as I can remember using encoders (nearly 10 years now).

Re: Team 254 Presents: 2013 Build Blog
 

I thought it was rather bizarre as well until I learned it while on 968. It really works a treat, and ensures that there is no binding or misalignment anywhere. As Travis mentioned, the bearing friction is very minimal, so there is no real load on the wires.

Re: Team 254 Presents: 2013 Build Blog
 

It's also really nice in that it's darn short axially. Lets you sneak them in on a lot of things real easy.

Re: Team 254 Presents: 2013 Build Blog
 

This year we used a couple 050 brackets to prevent the encoder from rotating. The idea was to connect the 2 pieces with a loose bolt so the encoder was prevented from rotating but still allowed to translate based on the alignment. The idea worked well until at some point the students found a "loose bolt" and tightened it. This led to 2 broken S4 ball bearing shafts.

One thing I learned was the shaft on the S4 is actually only 1/8" in diameter when it necks through the ball bearing. See images below.

I'm liking the wire + zip-tie idea!

Attachment 15200
Attachment 15201

Re: Team 254 Presents: 2013 Build Blog
 

Sorry to keep derailing this thread.....I called to order the S4 from US Digital, it seems that they are having a manufacturing problem and as such they will only sell their current inventory to customers who have ordered them in the past.

Being that we haven't used them in the past it looks like we can't order them. Does anyone have an alternative encoder we can use?

Kelly

Re: Team 254 Presents: 2013 Build Blog
 

We had great performance from the Grayhill encoders recommended by VexPro for their ball shifters. We got ours from DigiKey.

http://www.vexrobotics.com/vexpro/ge...l-shifter.html

Re: Team 254 Presents: 2013 Build Blog
 

Great idea Travis, Thanks for sharing.

This year Team 751 is going to try using an organization tool called Trello. This is a an open source project management system popular amongst new product developers here in Silicon Valley.

Instead of a blog, which tells you what was done, this is a task tracking system were people can tackle unknown problems and collaborate and monitor progress on the task. I am pretty sure it will work well as a mobile app for Android or iOS.


“The motto of all the mongoose family is, "Run and find out," and Rikki-tikki was a true mongoose.”

― Rudyard Kipling, Rikki-Tikki-Tavi