FRC 71 2002 Marching technique

[Roboshant]

I was watching this video of team 71 Hammond in 2002 and noticed their marching mechanism. Does anyone know how this actually works, or what 71 used for this.

Thank You!

[BigJ]

The surface going on the carpet is file cards - the short straight prickly metal brush on the tool you use to clean a file. The metal teeth of the brush dug into the carpet, basically couldn't be moved while in, and had to be picked straight up. It used pairs of the file cards to walk/march down the field. This also means the robot couldn't really ever turn itself, which was one of the only weaknesses of the design. This file card drive is believed to be the reason for the "no metal contacting the carpet" rule.

Source: I know the guy who drove it

Edit: If you mean what kind of linkages or how they produced the marching motion, I'm not sure, but I can probably get him on here to answer if noone else knows.

[IKE]

It works pretty similar to the treads of an elliptical exercise machine.

There is a swing link, a tread link, and a rotoray crank that raises, drives forward, lowers, pulls backwards. It is a very clever walker.

There are a handful other "4-bar" style mechanisms that can produce similar motion profiles.

[marshall]

Originally Posted by BigJ

This file card drive is believed to be the reason for the "no metal contacting the carpet" rule.

Ohh yes, rule 5.5.71.

#TeamsThatHaveHadRulesWrittenBecauseOfThem

[Sperkowsky]

Originally Posted by marshall

Ohh yes, rule 5.5.71.

#TeamsThatHaveHadRulesWrittenBecauseOfThem

Hmm I wonder who's going to start that club.

[Taylor]

Originally Posted by Sperkowsky

Hmm I wonder who's going to start that club.

There are several teams in that club. The don't flip robots rule is another (I don't remember the team but I believe they were from FL), as well as the robots can't start on top of each other rule (111). We claim partial responsibility for the cylindrical extrusions beyond frame perimeter rule.

[Ari423]

Originally Posted by Sperkowsky

Hmm I wonder who's going to start that club.

We claim partial responsibility for the exception to R77-K (disallowing White Clippards). In 2014, we blew up 3 or 4 of them in one event by playing hard defense. A day or two later, the Team Update adds that exception to the rules. Coincidence? I think not.


PS- I know we aren't the only team that did that, but it's nice to know we were part of the reason that rule was written.

[BigJ]

Originally Posted by Ari423

We claim partial responsibility for the exception to R77-K (disallowing White Clippards). In 2014, we blew up 3 or 4 of them in one event by playing hard defense. A day or two later, the Team Update adds that exception to the rules. Coincidence? I think not.


PS- I know we aren't the only team that did that, but it's nice to know we were part of the reason that rule was written.

Some(?) of the white Clippards just had manufacturing defects. In 2013 one blew up in our pit at Midwest, even before getting anywhere near fully pressurized. A piece ricocheted off my shoulder clear down the pit isle 30-40 feet! That was a fun time helping the inspectors hunt down all the pieces so they could investigate and send the stuff back for analysis.

[Amanda Morrison]

Originally Posted by Roboshant

I was watching this video of team 71 Hammond in 2002 and noticed their marching mechanism. Does anyone know how this actually works, or what 71 used for this.

Originally Posted by IKE

It works pretty similar to the treads of an elliptical exercise machine.

There is a swing link, a tread link, and a rotoray crank that raises, drives forward, lowers, pulls backwards. It is a very clever walker.

There are a handful other "4-bar" style mechanisms that can produce similar motion profiles.

A closeup of the walker feet in action is available via this video:

https://youtu.be/CuFlA3Pt4HQ?t=2175

Go a few minutes before that and you'll see the entire design process, including each of Team Hammond's iterations on the design. Also, a great sneak peek of the 2002 Zone Zeal Kickoff broadcast is available starting here, with bonus footage of Team Hammond's strategic process:

https://youtu.be/CuFlA3Pt4HQ?t=1624

(Yes, that is a VHS player. 2002 is longer ago than it feels, sometimes.)

Bonuses in this video: young Dave Verbrugge, announcer Ron Partridge, Woodie MCing matches, and Team 71's 2002 Chairman's Video (they were a bit different back then).


But most relevant to this thread, the inimitable and incredible Woodie Flowers Award winner, Mr. Bill, once again predicts the future: https://youtu.be/CuFlA3Pt4HQ?t=2014

[Peter Matteson]

Originally Posted by Sperkowsky

Hmm I wonder who's going to start that club.

177 Claims responsibility for Lexan shields in front of driver stations (1996 iirc) and the scoring object is part of the robot when under the robot's control (2001).

There are several others but I don't actively keep the list anymore.

[EricH]

Originally Posted by Taylor

There are several teams in that club. The don't flip robots rule is another (I don't remember the team but I believe they were from FL), as well as the robots can't start on top of each other rule (111). We claim partial responsibility for the cylindrical extrusions beyond frame perimeter rule.

Actually, RI for the no tipping. Sadly, no video exists...

71 has no intentional detatching of robot parts, as well as the no metal on carpet.

469 inspired several combinations of rules this year (their 2010 robot).

1519 clarified the whole meaning of robot...

BUMPERS are required due to wedged-robot interactions in '05--I know team 980 was involved in the probable catalyst. (It was quite funny to call them out during a presentation on this sort of thing, with them sitting there...)

The part about "restricting driver vision" comes from team 60, some years back.

Somebody turn me off, quick!

[Mike Marandola]

Originally Posted by Taylor

as well as the robots can't start on top of each other rule (111).

Is this a rule? 87 started on top of 816 at Seneca. There's no way the refs didn't see it.

https://www.youtube.com/watch?v=LLjc3vKQcXQ

[EricH]

Originally Posted by Mike Marandola

Is this a rule? 87 started on top of 816 at Seneca. There's no way the refs didn't see it.

https://www.youtube.com/watch?v=LLjc3vKQcXQ

They apparently removed that rule for this year. There is no requirement for robots to not be contacting other robots.

[AllenGregoryIV]

Originally Posted by EricH

They apparently removed that rule for this year. There is no requirement for robots to not be contacting other robots.

Or to be touching the carpet. What was the plan in that match? I'm so confused.

Can a team build a very small "robot" (roboRIO, battery, bumpers, etc) and start on a partner, then all of their crossing count as two crossings? I don't think this is reasonable but it might be legal.

[EricH]

Originally Posted by AllenGregoryIV

Or to be touching the carpet. What was the plan in that match? I'm so confused.

Can a team build a very small "robot" (roboRIO, battery, bumpers, etc) and start on a partner, then all of their crossing count as two crossings? I don't think this is reasonable but it might be legal.

Only if the top robot's bumpers actually go between the shields. If they don't go between the shields, no crossing.