06-14-2010 07:57 AM

Edoc'sil

Re: pic: Vex @ IRI Teaser

Possibly a layout for some 3D photography?

06-14-2010 08:50 AM

JesseK

Re: pic: Vex @ IRI Teaser

A kitten-launching trebuchet?

Or perhaps the ball of yarn for the kitten?

06-14-2010 10:43 AM

Chris is me

Re: pic: Vex @ IRI Teaser

A hint: The structure for the actual object isn't drawn here. This is a simple sketch used to determine how to position things to make something like this work.

I'm making this challenge a lot harder than it needs to be, but that's because I want to learn!

06-14-2010 10:47 AM

Andrew Schreiber

Re: pic: Vex @ IRI Teaser

OH OH I know what it is!

06-14-2010 03:24 PM

jblay

Re: pic: Vex @ IRI Teaser

If this did look like what you were building it would be 254 from 06

06-14-2010 11:26 PM

PAR_WIG1350

Re: pic: Vex @ IRI Teaser

it's a flux capacitor

06-15-2010 03:41 PM

Nick Lawrence

Re: pic: Vex @ IRI Teaser

I like where this is going. Literally.

-Nick

06-15-2010 04:15 PM

Chris is me

Re: pic: Vex @ IRI Teaser

I'll like where it's going when I see it driven on the field.

06-15-2010 05:12 PM

Pjohn1959

Re: pic: Vex @ IRI Teaser

Could it be this year's first successful hanging mechanism???

06-15-2010 05:25 PM

Nick Lawrence

Re: pic: Vex @ IRI Teaser

Well I guess you'll like it, one way or another.

-Nick

06-15-2010 05:38 PM

Chris is me

Re: pic: Vex @ IRI Teaser

Sadly, the Vex game at the IRI does not feature a hanging element. It is a modified 1v1 version of Clean Sweep called "Swept Away". You can view the rules here: http://content.vexrobotics.com/docs/...l.20091014.pdf

06-15-2010 06:16 PM

Alex Cormier

Re: pic: Vex @ IRI Teaser

I'd rather see it coming off the field as I am coming on.

06-15-2010 08:19 PM

gblake

Re: pic: Vex @ IRI Teaser

Too late for that. The Kiwis claim to have already put an autonomous high-hanging bot on the field in an official tournament.

http://www.vexforum.com/showthread.php?t=22267

Blake

06-16-2010 11:59 AM

Pjohn1959

Re: pic: Vex @ IRI Teaser

Yea, I read that right after my post. I would have liked to have seen that. Interesting enough, that was in our game plans as well...

06-26-2010 10:29 AM

Chris is me

Re: pic: Vex @ IRI Teaser

Well, I'm abandoning this so I might as well post what it is.

I was planning on making a totally sweet four bar linkage that would lift a forklift-style plate from flat at ground level, to titled back just off the ground (pick up game pieces spatula style), to tilted forward at 18 inches high (for scoring in the highest goal in the game). I graphically determined the position of the third and fourth point on the linkage by making approximate positions for the end piece in Solidworks, then finding points based on the intersections of the midpoints between linkage positions. I then tested the concept by making a model out of SolidWorks blocks just to make sure I derived the linkage correctly, and it worked just as predicted. I was then going to take the points in space and make a "vex-approximate" version that kind of did the same thing, but by that point I had decided on a simpler, but less totally-sweet version.

I put up a little video of the linkage blocks for visualization purposes. if you're curious, here: http://vimeo.com/12874376. While really, really cool, with the bonus of allowing for a four motor drivetrain, it's probably for the best that I'm scrapping it. Simple wins.

06-28-2010 08:21 PM

Foster

Re: pic: Vex @ IRI Teaser

One of my VEX teams built a really nice 4 bar linkage for "Clean Sweep" season. It worked well they were pretty happy with it. Two building tips are to use double bearing blocks at the pivot joints (4 blocks total) The two blocks on each side give great stability of the joint. Likewise double collars on each end of the axles makes the joint less likely to come apart under stress.

The shoulder screws that are new this year are also a good choice for the pivot points.

If Simple = elegant = only the parts you need, then yes. Too simple may break at a critical time.

It's a shame you are so far away, I'd be happy to lend you some of my builders.