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-   -   Al's Annual Inspection Thread (http://www.chiefdelphi.com/forums/showthread.php?t=126381)

pfreivald 18-03-2014 16:55

Re: Al's Annual Inspection Thread
 
Quote:

Originally Posted by Bruceb (Post 1360961)
we were at Superior a couple weeks ago and I can tell you that there were NO penalties called for inside the frame perimeter contact. We have a lot of damage on parts that are well inside the frame perimeter so build them strong folks!!!!

Yet at Tech Valley there were many many many!

philso 19-03-2014 00:17

Re: Al's Annual Inspection Thread
 
Quote:

Originally Posted by Al Skierkiewicz (Post 1360949)
philso,
I obviously cannot make an interpretation based on a description, that would be for your inspector to decide and of course for the Q&A to answer if it is something that hasn't been seen in the past. In general, bumpers using an angle to secure the corners has been allowed in the past. This is provided all other bumper rules are in compliance (the 1/4" gap rule and support in the corners for instance). As always, bumper construction is examined for weight, specifically for the maximum, and for any weight that should be correctly attributed to the robot weight.
Please remember that even if you have reversible bumper covers, the removal by one person in fifteen minute guideline still applies. We don't want you to miss a match because we need to accurately weigh your robot for some reason, only to find out it takes 30 minutes to get the bumpers off. I have seen one robot this season already that riveted their bumper system on to the robot frame thinking they would never have to remove them. That became very evident when the bumper fabric got ripped off in their second practice match.

Thanks for your feedback, Al.

At this time, I have no photos to show since I am trying to do my homework in case it is decided to replace our current bumpers with ones that will hold up to the abuse better. We would not want to put the time and effort into building something that has no hope of passing inspection. I would like to use corner brackets that extend at least 6" from the corners to resist the twisting we are getting because the contact with the frame is made in the lower 1 1/2" of the bumper. We will be using our current scheme to install and remove the bumpers. It takes about 2 minutes to swap between the two.

My main concern is that the corner brackets I am proposing would essentially cover the whole inside vertical surface of the bumpers, extending from the bottom to the top (5" high) and all the way around. The bumpers would end up consisting of an 1/8' thick layer of aluminum on the inside, 3/4" plywood, then the pool noodles on the outside. There would not be any gap between the aluminum and the plywood. The cloth covering would be trapped between the aluminum and the plywood. It would be the 1/8" aluminum plate that would contact the frame instead of the plywood. Does this sound like something that would be accepted at inspection?

Thanks.

Phil

Al Skierkiewicz 19-03-2014 08:21

Re: Al's Annual Inspection Thread
 
Phil,
This was asked on the LRI telephone conference last night. It sounds like you are planning a legal implementation, again providing all bumper rules are met. I reminded LRIs that the 1" hard parts restriction still applies, so consider that as well. The 1" extends out from the Frame Perimeter, not the back of the bumper. So if your mod is affected by hardware or other protrusions on the frame, it may not pass inspection.

philso 19-03-2014 13:00

Re: Al's Annual Inspection Thread
 
Thanks again for your help, Al.

I studied the Game Manual, Team Updates and Q&A, several times before working this out and will be watching out for the items in your comments. I had not seen any teams putting sheet metal between the bumper wood and the frame so I wanted to make sure we weren't going to go down the wrong path.

Phil

Al Skierkiewicz 19-03-2014 13:15

Re: Al's Annual Inspection Thread
 
Phil,
Many teams have done this for many years. WildStang is trying the same idea this year.

AllenGregoryIV 19-03-2014 13:25

Re: Al's Annual Inspection Thread
 
Quote:

Originally Posted by philso (Post 1361324)
Thanks again for your help, Al.

I studied the Game Manual, Team Updates and Q&A, several times before working this out and will be watching out for the items in your comments. I had not seen any teams putting sheet metal between the bumper wood and the frame so I wanted to make sure we weren't going to go down the wrong path.

Phil

Here is an in depth look at our bumpers this year. They held up really well.

http://blog.spectrum3847.org/2014/03...d-bumpers.html

DRH2o 23-03-2014 08:54

Re: Al's Annual Inspection Thread
 
The Virginia Regional did a wonderful job with inspections this year. With all the snow this year in areas that are not used to it there were a lot of unfinished robots. They had inspectors that came to you, or you could go to an inspection area. When there were a handful of teams not inspected Friday morning, inspectors took chairs to their pits to be there and answer questions. GREAT JOB Tom and crew -- especially Chuck - my kids called you Santa :)

Al Skierkiewicz 25-03-2014 23:23

Re: Al's Annual Inspection Thread
 
I would like to remind everyone of the rough game that were are playing this year. If you are playing in your first event this weekend or next, do not be surprised if your robot inspector points to items he would like to see fastened to your robot. In particular, the bumpers and the battery. Batteries are receiving as much external damage from hitting items inside the frame as they would from a drop. Bumpers are hit so hard that many mounting systems are failing. Remember that under G20, a robot can be disabled should the bumpers fail during the match. I have had several teams tell me that their bumpers failed in spite of their using the "lift test" described elsewhere.
I also want to remind teams that any changes, no matter how small, you make to your robot must be reinspected. If you add something or take something off, we need to know what the new weight is and we need to inspect the change to be sure structural integrity is good and no other items have been compromised. This reweigh helps get you through final inspection quicker and helps us get through all the teams prior to alliance selection. This is a very serious issue, without the reinspection, you are playing with a un-inspected robot. Many teams are taking off shooters and adding ballast to become a better defensive robot. These changes are often done in haste and therefore without regard to the effect it might have on other robot functions. Let your inspection team be your eyes and ears as they can look at your robot with a little clearer vision and help you get the design you are trying to achieve. We really want you to win. We feel we are part of your team.
There have been two very clear issues with teams this past week. One is the mounting of the plastic tanks on arms and moving appendages of the robot. Not only is this a poor choice for air flow (the tubing length is excessive), it exposes the tanks to hits from other robots. Excessive current causing power to brownout on the robot. This can bring about temporary loss of the radio, full reboot of the radio and/or cRio, fault conditions on Jaguars and shutdown of digital I/O and DSC. Be sure all primary wiring (battery, main breaker and PD input) is tight, both crimp and screw terminals and the hardware. This is a real issue for teams running inefficient drive systems.
Good Luck Everyone.

rrossbach 26-03-2014 00:04

Re: Al's Annual Inspection Thread
 
Quote:

Originally Posted by Al Skierkiewicz (Post 1364913)
There have been two very clear issues with teams this past week. One is the mounting of the plastic tanks on arms and moving appendages of the robot. Not only is this a poor choice for air flow (the tubing length is excessive), it exposes the tanks to hits from other robots.

Al -
Could you elaborate on how LRI's have been advised to handle a robot with an air tank mounted this way at upcoming events?

- Ron
Team #2607 controls mentor

Al Skierkiewicz 26-03-2014 08:09

Re: Al's Annual Inspection Thread
 
Ron,
It is wise to move it down inside the robot away from the possibility of it getting hit. I would like LRIs to try and convince the team of the risk of such mounting. When a team uses air as part of their ball handling or shooting, loosing that air will put them out of business for the remainder of the match. Even something as simple as a hose getting pulled out will have that effect. The plastic tanks may fail if hit hard with a metal arm on another robot or in a collision. It doesn't violate any specific robot rules, it is just bad practice.

nathannfm 26-03-2014 08:11

Re: Al's Annual Inspection Thread
 
Al,

Could you give guidance on a mounting system like this, mainly the part in red: http://screencloud.net/v/8UUP

The green parts are our robot / frame perimeter, everything else is BUMPER. We have used the wing nut/stud method before so I am not worried about that. My main concern is the (red) aluminum 2.5x1 angle that rises above the top of the bumper. Everything remains in the 2-10in bumper zone, but I have never seen an attachment method that went above the bumper itself in recent years. I can't find a rule this would violate and our own LRI, Brian Lucas, says it's fine, but this really seems like it's pushing it. I just wanted to get a second opinion before we start cutting metal.

Thanks.

cgmv123 26-03-2014 09:27

Re: Al's Annual Inspection Thread
 
Quote:

Originally Posted by nathannfm (Post 1364986)
Al,

Could you give guidance on a mounting system like this, mainly the part in red: http://screencloud.net/v/8UUP

The green parts are our robot / frame perimeter, everything else is BUMPER. We have used the wing nut/stud method before so I am not worried about that. My main concern is the (red) aluminum 2.5x1 angle that rises above the top of the bumper. Everything remains in the 2-10in bumper zone, but I have never seen an attachment method that went above the bumper itself in recent years. I can't find a rule this would violate and our own LRI, Brian Lucas, says it's fine, but this really seems like it's pushing it. I just wanted to get a second opinion before we start cutting metal.

Thanks.

I won't attempt to comment on the legality, but I'd be concerned about how the 2.5x1 angle attaches to the wood. That seems like the weak point. Bolts through the wood are a necessity. Screws won't cut it.

Jon Stratis 26-03-2014 09:53

Re: Al's Annual Inspection Thread
 
Quote:

Originally Posted by nathannfm (Post 1364986)
Al,

Could you give guidance on a mounting system like this, mainly the part in red: http://screencloud.net/v/8UUP

The green parts are our robot / frame perimeter, everything else is BUMPER. We have used the wing nut/stud method before so I am not worried about that. My main concern is the (red) aluminum 2.5x1 angle that rises above the top of the bumper. Everything remains in the 2-10in bumper zone, but I have never seen an attachment method that went above the bumper itself in recent years. I can't find a rule this would violate and our own LRI, Brian Lucas, says it's fine, but this really seems like it's pushing it. I just wanted to get a second opinion before we start cutting metal.

Thanks.

So long as the top of the red portion is completely within the bumper zone, I don't see a problem with it passing - it looks like a legal method of attachment (provided all other bumper rules are met, of course - for example, we can't tell from the image how often it's attached, or if there are gaps between the bumper and the frame)). I will caution: This is a very hard hitting game. I could potentially see the bumper rotating into the red piece, causing it to bend. I would recommend having something in place, like vertical supports on the robot between the two frame sections, to prevent the bumper from rotating when hit.

nathannfm 27-03-2014 17:37

Re: Al's Annual Inspection Thread
 
Thanks for the replies, we do comply with all other bumper rules, looks like we will be going ahead with this modification.

Quote:

Originally Posted by cgmv123 (Post 1365018)
Bolts through the wood are a necessity. Screws won't cut it.

I know, we have used hammer in thread in the other end of the wood for many years and they hold up well, the only problem is that when we want to modify their location we need to unwrap it which is a pain.

Bill_B 27-03-2014 18:51

Re: Al's Annual Inspection Thread
 
Looks to me that the bumper is more than 5" tall that way if the red part comes off with the wood backing. Unless your bumpers are already at the 10" height you may want to duplicate the lower angle stock so that the two angle (gray) pieces extend in above the lower green tube and below the upper one. Then slide the wood up a little to give good connection basis for the gray pieces.

Al Skierkiewicz 30-03-2014 20:43

Re: Al's Annual Inspection Thread
 
Nathan,
I would agree with Jon' assessment of the picture you provide and reiterate the violent nature of this game requires the need for secure mounting. However, I have not seen this method used before and it would be best to ask the Q&A for the definitive answer.

Wayne Doenges 18-04-2014 19:18

Re: Al's Annual Inspection Thread
 
Inspection at Championship will be just like at any of your regionals.
If we find something wrong, that was missed at your regional, PLEASE don't tell us that "This robot passed XXXX Regional."
We are all human (though I'm not to sure about Big Al :D ) and we miss things. Please remain calm and we will do everything in our powers to get your robot passed to play Thursday.
No Robot Left Behind.


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