Team 971's CAD Archive Release
 

Team 971 is releasing our CAD files for our robots going back to 2007 (the first year we designed with CAD). You can find our robots and what associated information we have collected about them on our website at:

http://frc971.org/cad

If you have any questions, you can post them here or contact our team via http://frc971.org/contact.

Re: Team 971's CAD Archive Release
 

This is fantastic. Thank you so much.

Re: Team 971's CAD Archive Release
 

Today is a good day.

Re: Team 971's CAD Archive Release
 

Agreed. I love seeing world class teams like 118, 1114, 67, and now 971 releasing CAD models. Not only is it something that is great to geek out over, but I think anyone that takes the time to look into these models stands to learn something new about design or CAD in general.

Re: Team 971's CAD Archive Release
 

All,
Here's a direct link to this year's technical document as well. We will post past year's technical information as well. You can access the technical information through the CAD model page. We're in the process of adding all the information from past years.

http://frc971.org/files/TechnicalDocument-971-2014.pdf

Feel free to ask any questions.

Re: Team 971's CAD Archive Release
 

Page not found error?

Re: Team 971's CAD Archive Release
 

It worked 2 minutes ago. I'll grab a good link and post it.

Edit: We're editing the page. We should have a link by around tomorrow.

Re: Team 971's CAD Archive Release
 

How do you guys get everyone to cad at that level? Simply amazing.

Re: Team 971's CAD Archive Release
 

The CAD wont open on my computer. When i go to open it Solidworks crash's.

Re: Team 971's CAD Archive Release
 

Let me know if this link works (might be the same one, but would work now).

I'll also see about uploading to CD media, so people can find it again.

http://frc971.org/files/2014-TechnicalDocumentation.pdf

Re: Team 971's CAD Archive Release
 

That link works, thank you all for posting this and your CAD files. They are going to be great learning tools.

Re: Team 971's CAD Archive Release
 

It is part of our team culture. We have traditionally been a team with some amazing sponsors, and very rudimentary tools in house. We have no choice but to detail everything out, get it right the first time, and get it drawn quickly. Sponsors need detailed models and drawings. Not seen are the detailed drawings of every part on those robots required to get the parts made. This is slowly starting to change as we get better tools in house. We've gotten good over the years at spreading the load to speed up design and maintain the high standard needed to succeed. More experienced CADers work with mentors to do the high level design and mechanism design. After that is done, it can be passed on to students at other levels who can draw axles, spacers, and add rivet holes.

The year, for example, we had the robot that we competed with essentially completely drawn, and all the major parts out to sponsors by the end of week 2. We then got 3 week turn on some of the parts, 2 week on others, and spent the last week assembling our robot. Most years, we only get a couple extra machined parts after the big run of parts.

Re: Team 971's CAD Archive Release
 

It is best to get to the technical documentation through the download page in the original post by Travis. All of the links will be tested and correct. Individual pages might change.

Re: Team 971's CAD Archive Release
 

Very cool. gonna pass this to the 3309 and 3476 students.

Re: Team 971's CAD Archive Release
 

Sorry I missed your comment last night.

I just tried opening the 2007 Robot STEP file on a pretty slow computer and it worked for me. What file(s) did you have trouble opening? Does anyone else have this problem?

Re: Team 971's CAD Archive Release
 

How did you guys figure out all the center to center spacing on your belt reductions in your top jaw?

https://scontent-b-lga.xx.fbcdn.net/...c9&oe=545E6457

Re: Team 971's CAD Archive Release
 

It's not center-center spacing. From what I can see, there's a Cam (which looks like a bearing attached with a hex nut) used to adjust the tension of the belt.

Re: Team 971's CAD Archive Release
 

It's not actually a cam, it's just a bolt in a slot which we push on until it is tensioned and then tighten down.

Re: Team 971's CAD Archive Release
 

Alex,

I uploaded a thread in the CD media that shows the sketch we used for our shooter gearbox (it is the same principle, just a cleaner example of it). The picture is accompanied with a description. Please let us know if you have any further questions about this.

http://www.chiefdelphi.com/media/photos/40812?

Also, for note, we are not entirely pleased with our tensioner slot method. We have found that once you tighten down the bolt, even with a fat washer, the material gets swagged into the slot, and the blot doesn't slide freely the next time. This could be improved with more clearance (in hind sight the .252 clearance was un-necessarily close) coupled with possibly a different clamping method. We will see what we decide to do next season.

Re: Team 971's CAD Archive Release
 

So I was looking at your gearbox and I'm a little confused as to how the CIM motor shaft extension is held on. Is is press fit onto the CIM motor or is keyed?

Re: Team 971's CAD Archive Release
 

Press fit. We did all the math to make sure it won't slip.

Re: Team 971's CAD Archive Release
 

Starting in 2011 or so, we'd ream .001 under and just hoped it would work!

We tested torque required to slip and found it exceeded what we need by a good margin. I mean we used a 3-4 ft lever arm w/ some weights.

Re: Team 971's CAD Archive Release
 

Awesome, thanks for the data point! I believe we used a 0.0015 press, which just worked for similar reasons. That was some fun math to do. You can treat the hex like a pressure chamber, and figure out the force required to slip it. I remember calculating that we needed 300 lbs of force to press it on.

This year, we left a step at the end of the bore so we could press it on until it hit the end of the CIM shaft. That worked well. You can see it in the model.

Re: Team 971's CAD Archive Release
 

You could also leave a small pilot hole on the end to insert a pin gauge to determine the press depth and to relieve the pressure while pressing on the adapter.