Rules Question
 

Posted by Patrick Dingle at 2/1/2001 9:14 AM EST


Other on team #639, Red B^2, from Ithaca High School and Cornell University.



I couldn't seem to get the answer from FIRST, so I figured I'd ask and see if anyone knows here...

Is it allowed to use bolts in a way such that they act as a shaft? An example of this would be at joints and such.

Thanks
Patrick
T639 Red B^2

Re: Rules Question
 

Posted by Josh Vetter at 2/1/2001 10:01 AM EST


Student on team #548, Robostangs, from Northville High School and BOSCH.


In Reply to: Rules Question
Posted by Patrick Dingle on 2/1/2001 9:14 AM EST:



I don't see why not. The additional hardware list has fasteners on it, and a bolt would be a fastener. It does't say what you can and can't use them for.
Josh

: I couldn't seem to get the answer from FIRST, so I figured I'd ask and see if anyone knows here...

: Is it allowed to use bolts in a way such that they act as a shaft? An example of this would be at joints and such.

: Thanks
: Patrick
: T639 Red B^2

Re: Rules Question
 

Posted by ChrisH at 2/1/2001 10:15 AM EST


Engineer on team #330, Beach 'Bots, from Hope Chapel Academy and NASA JPL, J & F Machine, Raytheon, et al.


In Reply to: Rules Question
Posted by Patrick Dingle on 2/1/2001 9:14 AM EST:



: I couldn't seem to get the answer from FIRST, so I figured I'd ask and see if anyone knows here...

: Is it allowed to use bolts in a way such that they act as a shaft? An example of this would be at joints and such.

: Thanks
: Patrick
: T639 Red B^2

The traditional definition of a fastener has been "anything that holds two or more parts in fixed relation to each other". So if the parts don't rotate or slide in relation to each other it doesn't matter what holds them together. If they do whatever holds them together needs to be from a "legal" source.

Of course this is enforced by the judges and sometimes things slip through, so your mileage may vary. But following this rule is a pretty safe bet.

my $0.02

Chris Husmann, PE
Team 330 the Beach'Bots

bolts = shafts (imho)
 

Posted by Matt Berube at 2/1/2001 11:11 AM EST


Engineer on team #49, Delphi Knights, from Buena Vista High School and Delphi Automotive.


In Reply to: Rules Question
Posted by Patrick Dingle on 2/1/2001 9:14 AM EST:



I think that we have used those fancy ground shaft shoulder bolts as shafts on each robot we have made over the past 4 years. We have never had a judge look twice at them. I believe that this is well within the spirit of the "fastener rule". My opinion is that FIRST does not want us to use the bolts as ballast, or melt them down for raw material, or machine them into something exotic. Also, alot of the bolts you may want to use are available in the small parts book.

Matt B.
T49
"that OTHER Delphi team"

a matter of opinion
 

Posted by Ken Leung at 2/1/2001 12:43 PM EST


Student on team #192, Gunn Robotics Team, from Henry M. Gunn Senior High School.


In Reply to: Rules Question
Posted by Patrick Dingle on 2/1/2001 9:14 AM EST:



We all know we can always use raw material to make our own shaft, and it's not hard using steel rod and attach it with a head, and use a die to thread the end. So the issue is if FIRST will allow teams with lesser resource just use bolts as a quick solution to making joints. Personally I don't think they care that much, because it is not a big issue that really matters. And in a sense it kind of levels the field out there.

Usually, judges are not going to take too close of a look into what the robot is made out of, and they trust the teams and their gracious professionalism to keep them in order.

So for now, I suggest you use bolts as joints, and later replace them with steel rods if they are not going to allow bolts to be used such a way. You don't want such a small problem delay your production.

Re: Rules Question - Play it safe
 

Posted by Raul at 2/1/2001 1:06 PM EST


Engineer on team #111, Wildstang, from Rolling Meadows & Wheeling HS and Motorola.


In Reply to: Rules Question
Posted by Patrick Dingle on 2/1/2001 9:14 AM EST:



Patrick,

Regardless of what anyone says on this forum, I suggest that you play it safe and buy a shoulder bolt from Small Parts. They have many good size bolts for under $2. If later, you get a beneficial ruling, you can deduct the $2 from your official SP list.

Here is what (I think) I know:

There have been a lot of questions about this in past years and the interpretation was usualy that it could be used as a link pin but not as a shaft.

If my failing memory serves me (and I'm asking for help from some of the other veterans), the quote was something like: " if the object being held by the bolt rotates more than 360 degrees then it is not considered a fastener and therefore must come from Small Parts." ISo a wheel on a bolt would make the bolt a shaft, not a fastener. If on the other hand it holds something like a 4-bar linkage that does not make a complete rotation, then it is still considered a fastener.

Raul



: I couldn't seem to get the answer from FIRST, so I figured I'd ask and see if anyone knows here...

: Is it allowed to use bolts in a way such that they act as a shaft? An example of this would be at joints and such.

: Thanks
: Patrick
: T639 Red B^2

Re: Rules Question - Play it safe
 

Posted by Jim Meyer at 2/1/2001 2:02 PM EST


Engineer on team #67, HOT Team, from Huron Valley Schools and GM Milford Proving Ground.


In Reply to: Re: Rules Question - Play it safe
Posted by Raul on 2/1/2001 1:06 PM EST:



To add to what Raul said I also vaguely remember Dean saying something like "If this so-called bolt is holding two pieces of your frame together and happens to have a wheel on the end of it, well...." Implying that this was legal.

Anyone else remember anything like this?

Maybe I was just dreaming.

Last year we did not use a bolt exclusively as a fastener. We usually slipped a piece of SPI purchased Oil-Lite (sp?) over a bolt and then bolted the Oil-Lite to the aluminum. We were tempted to use shoulder bolts but not having any SPI ones on hand pushed us toward other faster alternatives.

Jim

OFFICIAL response regarding use of bolts
 

Posted by Patrick Dingle at 2/1/2001 9:40 PM EST


Other on team #639, Red B^2, from Ithaca High School and Cornell University.


In Reply to: Rules Question
Posted by Patrick Dingle on 2/1/2001 9:14 AM EST:



Thanks for all your opinions on the matter. I finally got feedback from FIRST, and here it is:

-------------------------
Patrick

Bolts used as shafts are not considered to be fasteners, and therefore
would not qualify under Additional Hardware. Any bolts used in this
fashion would have to from Small Parts Inc.

CJ
------------------

Patrick

I don't see the logic
 

Posted by Gary Bonner at 2/2/2001 12:53 PM EST


Other on team #433, Firebirds, from Mount Saint Joseph Academy and SCT Corp., FMC Corp..


In Reply to: OFFICIAL response regarding use of bolts
Posted by Patrick Dingle on 2/1/2001 9:40 PM EST:



This baffles me. Last year, the additional hardware list specifically limited the use of fasteners to joining only. FIRST then eliminated that restriction in a Team Update (changed to the exact wording used this year), and in the Q&A gave very liberal interpretation to the use of materials that had no restrictions. (For example, you could melt and re-extrude aluminum and exceed the 2X3 inch limit.) This year, fasteners have no restrictions on the additional hardware list. Now, with less than 3 weeks to go, we get and interpretation that you can’t use them to fasten your wheels to you robot. What other hidden restrictions are there? Are we supposed to ask for a clarification for every circumstance that isn’t specifically and clearly covered in the rules? And then wait a week for the answer?

the logic has not changed
 

Posted by Ken Patton at 2/4/2001 12:40 PM EST


Engineer on team #65, The Huskie Brigade, from Pontiac Northern High School and GM Powertrain.


In Reply to: I don't see the logic
Posted by Gary Bonner on 2/2/2001 12:53 PM EST:



Gary, the logic that FIRST is using has not changed, in my opinion. You are not *fastening* your wheels to the robot if you allowing them to rotate about the bolt. What FIRST is saying is that you have a axle, not a fastener, through the center of your wheel. And axles are not on the AHL.

This is what they have always said, in one form or another. IMHO

Ken

Re: the logic has not changed
 

Posted by Gary Bonner at 2/5/2001 12:29 PM EST


Other on team #433, Firebirds, from Mount Saint Joseph Academy and SCT Corp., FMC Corp..


In Reply to: the logic has not changed
Posted by Ken Patton on 2/4/2001 12:40 PM EST:



Last year was my first year, so I have no experience before that, but I’d have to say that FIRST has changed their views on the use of fasteners.

From the 2000 Additional Hardware List:
Fasteners, Washers, Nuts, Adhesives - Any amount - Joining ONLY

From 2000 Team Update #7:
CORRECTIONS AND UPDATES TO THE MANUAL
The following parts have been modified in the Additional Hardware List as follows:
Fasteners, Washers, Nuts, Adhesives - Any size, Any amount

From 2000 Team Update 9:
Q222. What is the limitation on the usage of Velcro? Does it fall under the category of Fasteners, Washers, Nuts, and Adhesives in the Additional Hardware List?
A222. Velcro is a fastener. Fasteners are listed on the Additional Hardware List and the use is no longer limited to "Joining ONLY" as of Team Update #7.

I can understand that “fastening” the wheels to the robot may not be the best example, but, there are plenty of other applications, such as a pivot points or linkages, where a fastener may not be just fastening. Are these also not legal uses? Where do you draw the line? It seems to me that it should be either no movement at he joint, or no restrictions on use of fasteners. Anywhere else is arbitrary. What purpose would the rule serve? It certainly is not leveling the playing field. A ten cent bolt available at any hardware store vs. purchasing something from Small Parts that has to be modified. SP doesn’t even sell common steel screws or bolts.

definitions
 

Posted by Ken Patton at 2/5/2001 10:20 PM EST


Engineer on team #65, The Huskie Brigade, from Pontiac Northern High School and GM Powertrain.


In Reply to: Re: the logic has not changed
Posted by Gary Bonner on 2/5/2001 12:29 PM EST:



Gary-

I was surprised to see year 2000 Q222 and A222. Has FIRST said anything like that for THIS year? My understanding has always been the following:

Fastener: holds two structures together so that they do not move relative to each other; usage is not limited

Axle: allows rotation greater than 360 degrees (like the wheel axle); must be made from SPI matls, AHL matls, or bought from SPI

Pin in Link: allows rotation less than 360 degrees; usage is not limited

Any twisting of the definition of "fastener" to allow relative motion makes the fastener not a fastener anymore, imho.

Ken

Update 6 answers this...
 

Posted by Nate Smith at 2/7/2001 12:39 PM EST


Other on team #66, GM Powertrain/Willow Run HS, from Eastern Michigan University and GM Powertrain.


In Reply to: definitions
Posted by Ken Patton on 2/5/2001 10:20 PM EST:



Q166: Are bolts used to attach the wheelchair wheels to the robot (allowing them to rotate) considered "fasteners" (allowed) or "shafts" (not allowed)?
A166: Bolts are considered fasteners no matter how they are used. This is a change in interpretation from previous years.

Re: Update 6 answers this...
 

Posted by Alan Partington at 2/10/2001 2:27 PM EST


Student from Crescent School.


In Reply to: Update 6 answers this...
Posted by Nate Smith on 2/7/2001 12:39 PM EST:



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