View Full Version : pic: Carmen week1 team 842
falconmaster
11-01-2009, 03:11
[cdm-description=photo]32317[/cdm-description]
GarrettF2395
11-01-2009, 03:18
Wow, I am really impressed by your design!:D
So this is basically an ackerman steering chassis?
How do you plan on implementing the differential?
How many hours have you guys worked during week 1? :confused:
GaryVoshol
11-01-2009, 06:52
Oh, oh. Check the bumper rules. You can't attach a legal standard bumper to those angled faces in front.
thehurd03
11-01-2009, 08:07
Oh, oh. Check the bumper rules. You can't attach a legal standard bumper to those angled faces in front.
They don't have to, The rules say you have to cover 75% (I think) of the perimeter of your robot.
Jimmy Cao
11-01-2009, 09:10
They don't have to, The rules say you have to cover 75% (I think) of the perimeter of your robot.
2/3, but they also must cover all corners.
It looks rather impressive. Excellent progress for week 1! Good job.
They don't have to, The rules say you have to cover 75% (I think) of the perimeter of your robot.
I would worry about bumper rule I:
BUMPERS must protect all exterior corners of the BUMPER PERIMETER
in combination with bumper rule A:
BUMPERS must be built in segments, with a minimum length of six inches, and a maximum
length that does not exceed the maximum horizontal dimension of the ROBOT
So if you need to have a bumper on the front (that's the if), it must be 6 inches long and fastened to the hard robot frame, which in the pictured robot's configuration would put it inside the bumper perimeter and thus illegal according to bumper rule L:
The BUMPERS must be fixed to the BUMPER PERIMETER
Hanna2325
11-01-2009, 09:19
Wow, thats really nice :D
Your team needs to look at the update #2 and the bumper rules. Looks good so far. You've accomplished allot for week 1.
Looks good Carl Hayden! You always do produce a robot quickly and it's helped make 842 a formidable competitor at AZ every year. Our robot is still in the wood and duct tape testing stage!
Did you already order receive a second set of Toughboxes or are those just pulled from last year's robot?
MrForbes
11-01-2009, 11:14
I'm beginning to think that if you can figure out what the bumper rules mean, then you should be headed to law school, not engineering school :)
We're playing it safe and planning on having a rather conventional outside shape with bumpers covering most of it....and the front will have 6" bumpers on each side of the harvester, in a straight line.
falconmaster
11-01-2009, 12:11
Looks good Carl Hayden! You always do produce a robot quickly and it's helped make 842 a formidable competitor at AZ every year. Our robot is still in the wood and duct tape testing stage!
Did you already order receive a second set of Toughboxes or are those just pulled from last year's robot?
We ordered them on Mon.and got them Wed.
We are trying to give our programmers all the time we can, to day is our first time off and we feel guilty....
The other ting is we like to get stuff on here at CD to get the critiques so we can make improvements...
falconmaster
11-01-2009, 12:13
I'm beginning to think that if you can figure out what the bumper rules mean, then you should be headed to law school, not engineering school :)
We're playing it safe and planning on having a rather conventional outside shape with bumpers covering most of it....and the front will have 6" bumpers on each side of the harvester, in a straight line.
I am guessing then you are going wide drive....
falconmaster
11-01-2009, 12:15
I would worry about bumper rule I:
in combination with bumper rule A:
So if you need to have a bumper on the front (that's the if), it must be 6 inches long and fastened to the hard robot frame, which in the pictured robot's configuration would put it inside the bumper perimeter and thus illegal according to bumper rule L:
Does the bumper perimeter have to be rectangular? We are planning on running the bumper into our bot six inches.
Just for example... what if you had an L shaped robot?
MrForbes
11-01-2009, 12:22
I am guessing then you are going wide drive....
That's the plan right now.
http://www.chiefdelphi.com/media/photos/32297
shows the chassis design. The wood pieces are cut out and almost ready to assemble.
falconmaster
11-01-2009, 12:22
Wow, I am really impressed by your design!:D
So this is basically an ackerman steering chassis?
How do you plan on implementing the differential?
How many hours have you guys worked during week 1? :confused:
We will use differential steering on the rear wheels in the code, thats the programmers area, we are the builders, so thats all I can explain
MrForbes
11-01-2009, 12:25
How many hours have you guys worked during week 1? :confused:
They seem to be working on it almost all day every day during the week. If you want to check up on them, it's pretty easy....although it's Sunday today.
http://www.ustream.tv/channel/falcon-robotics-team-842
Where's the cRIO?Does the bumper perimeter have to be rectangular?BUMPER PERIMETER – the polygon defined by the outer-most set of exterior vertices on the ROBOT (without the BUMPERS or Trailer Hitch attached) that are within the BUMPER ZONE. To determine the BUMPER PERIMETER, wrap a piece of string around the ROBOT at the level of the BUMPER ZONE - the string describes this polygon. i.e. The bumper perimeter must be a convex polygon.
falconmaster
11-01-2009, 13:16
Where do the cRio and Spikes go? i.e. The bumper perimeter must be a convex polygon.
That is interesting, where does it say that it must be convex?
That would settle the dispute......
Thanks for helping to vet us. We don't want to caught at a regional with a violation.
That is interesting, where does it say that it must be convex?It never explicitly says that it must be convex, but wrapping a string around a concave polygon will result with the string not following the entire perimeter of the polygon. If you wrap a string around this robot in the bumper zone, it will form a convex rectangle.
falconmaster
11-01-2009, 13:47
definition per rules
To determine the BUMPER PERIMETER, wrap a piece of string around the ROBOT at the level of the BUMPER ZONE - the string describes this polygon.
We would have our string cross the opening of our bot. It does not say it has to make contact with the bumper zone everywhere. That is an assumption. Our polygon would be a rectangle, never the less we will cover the angles in from the corner with 6 inches of bumper. We think we are ok......I hope
We would have our string cross the opening of our bot. It does not say it has to make contact with the bumper zone everywhere. That is an assumption. Our polygon would be a rectangle, never the less we will cover the angles in from the corner with 6 inches of bumper. We think we are ok......I hopeWould the bumpers be straight (parallel with back of bot) or angled (parallel with angled front sides of bot)?
AdamHeard
11-01-2009, 13:52
definition per rules
To determine the BUMPER PERIMETER, wrap a piece of string around the ROBOT at the level of the BUMPER ZONE - the string describes this polygon.
We would have our string cross the opening of our bot. It does not say it has to make contact with the bumper zone everywhere. That is an assumption. Our polygon would be a rectangle, never the less we will cover the angles in from the corner with 6 inches of bumper. We think we are ok......I hope
I believe the intent is that bumpers must be on the bumper perimeter. You're taking a risky move, and should probably Q&A it.
GaryVoshol
11-01-2009, 14:04
I believe the intent is that bumpers must be on the bumper perimeter. You're taking a risky move, and should probably Q&A it.
It's not just the intent, it's the rule:
L. The BUMPERS must be fixed to the BUMPER PERIMETER.
What needs to be answered in Q&A is if every side of your robot must have bumpers in order to satisfy the requirement that corners are protected.
MrForbes
11-01-2009, 14:05
What needs to be answered in Q&A is if every side of your robot must have bumpers in order to satisfy the requirement that corners are protected.
That's the one that I haven't figured out for sure yet...and we're going to assume the answer is "yes". Which really limits the effectiveness of end loading narrow robots like Carmen, unfortunately.
It's not just the intent, it's the rule:
What needs to be answered in Q&A is if every side of your robot must have bumpers in order to satisfy the requirement that corners are protected.
Another team member pointed this out to me today: the first thing to contact a flat vertical obstacle (aka the wall) must be your bumper. If you have one side completely uncovered, then the first thing to hit that vertical obstacle will be metal.
falconmaster
11-01-2009, 16:19
Would the bumpers be straight (parallel with back of bot) or angled (parallel with angled front sides of bot)?
angled
Mike8519
11-01-2009, 22:50
Angled "bumpers" would not pass inspection because technically they are not bumpers at all since they do not lie on the bumper perimeter according to the current set of definitions and both sides of the corner must be protected.
MrForbes
11-01-2009, 22:57
Ahhh...here's that statement that seemed to me to be missing from the rules.
"2. As indicated in Rule <R08-I>, all exterior corners of the BUMPER PERIMETER must be protected by BUMPERS. Both "sides" of the corner must be protected."
from http://forums.usfirst.org/showthread.php?t=11159
falconmaster
11-01-2009, 23:56
Ahhh...here's that statement that seemed to me to be missing from the rules.
"2. As indicated in Rule <R08-I>, all exterior corners of the BUMPER PERIMETER must be protected by BUMPERS. Both "sides" of the corner must be protected."
from http://forums.usfirst.org/showthread.php?t=11159
Ok Well according to Jim we are possible ok since we will have the bumpers over the corners and the first part to touch a wall will be the bumpers. Let keep or fingers crossed!
MrForbes
12-01-2009, 00:21
The problem is the bumpers need to be on the bumper perimeter, which is the edge around the robot, and recessed parts of the frame are not the perimeter. So it looks to me like it's not legal. You'd have to put back the straight pieces across the front, but make them each 6" long, and cover them with 6" long bumpers. This will give a pretty small opening in the middle.
What a bummer, how vague the rules are this year on bumpers...they could have just come out and said what they wanted in the first place.
redbarron
12-01-2009, 02:32
I still do not understand why this is not legal.......... If they were to put the bumpers at an angle across those pieces as long as the bumper pieces were at least six inches long, and the corner was not exposed, why isn't this legal?
Mike8519
12-01-2009, 06:40
I still do not understand why this is not legal.......... If they were to put the bumpers at an angle across those pieces as long as the bumper pieces were at least six inches long, and the corner was not exposed, why isn't this legal?
Because angled bumpers are not bumpers at all. If they are not on the bumper perimeter they are superfluous padded chassis sections. If you take a piece of string around the outside of the robot (definition of bumper perimeter) the bumpers must be attached to the chassis where the string is.
BUMPER PERIMETER – the polygon defined by the outer-most set of exterior vertices on the ROBOT
(without the BUMPERS or Trailer Hitch attached) that are within the BUMPER ZONE. To determine
the BUMPER PERIMETER, wrap a piece of string around the ROBOT at the level of the BUMPER
ZONE - the string describes this polygon. The BUMPER PERIMETER may extend up to, but cannot
exceed, the maximum ROBOT volume constraints defined in Rule <R11>.
L. The BUMPERS must be fixed to the BUMPER PERIMETER.
Because angled bumpers are not bumpers at all.
This is not necessarily true
Mike8519
12-01-2009, 07:20
This is not necessarily true
What I should say is that bumpers on a concave angled portion of the robot are not bumpers. Robots with angled front edges.
Bumpers like http://www.chiefdelphi.com/media/photos/30834 are legal types since the bumper perimeter is along those edges
GaryVoshol
12-01-2009, 07:22
What I should say is that bumpers on a concave angled portion of the robot are not bumpers. They are bumpers, but they are not BUMPERS. They don't qualify under the <R08> rules, and would not be exempt from weight/size in <R11>.
Because angled bumpers are not bumpers at all.This is not necessarily true
It's important to keep in mind the difference between bumpers and BUMPERS. Some bumpers are not BUMPERS. Bumpers that are angled such that if extended infinitely would pass through the robot chassis are not BUMPERS, because they are not affixed to the BUMPER PERIMETER. As such, nothing attached to the angled pieces on Carmen's front can ever be considered a BUMPER, so even though the corners of the frame could be protected on both sides by pool noodles and fabric, they won't be protected by BUMPERS, and thus run afoul of <R08-I>.
I wonder if Inspectors would let this design through due to the potential to damage the field.
With the cantilevered front end, if the robot is struck and the front end dips, the metals will be in direct contact with the flooring, potentially gouging it or catching a seam ...
Maybe consider placing plastic carpet skids on the under side ...
XXShadowXX
12-01-2009, 08:15
what are you using pneumatics for?
Jared Russell
12-01-2009, 10:44
I have a vested interest in finding out whether this chassis design is legal. It would seem that the bumper rules require (1) that exterior corners are protected by BUMPERS on both sides and all trailer contact is bumper to bumper, and (2) that bumpers can only be attached to the BUMPER PERIMETER.
Unless I'm missing something, both of those conditions cannot simultaneously be met for the front of this robot (Which may or may not be the GDC's intention. Considering that this picture was posted in the Q&A and all that the GDC said was that exterior corners must be protected, it seems like this particular contradiction hasn't occurred to them.)
MrForbes
12-01-2009, 10:46
I think it has occurred to them, but they don't answer questions directly, they let you figure out the implications for yourself.
Paul Copioli
12-01-2009, 11:04
Fredi,
The robot looks great so far. If you are intending to place 6" of bumper on the internal, angled side then I think you are meeting the intent of the rule. However, the rule as written as a few wierd nuances that may get you in trouble.
Here is what I suggest:
1. Write another Q & A showing the exact picture of your robot with bumpers on all sides you intend to place them.
2. In the Q & A clarify theat the bumpers are all made per the BUMPER rules (plywood, etc.)
3. Specifically ask if the BUMPERS on the angled internal sides are considered BUMPERS or not. Ask if they will be considered in the robot weight or BUMPER weight.
What troubles me is that the bumpers on the internal sides are not really legal BUMPERS becasue they are not mounted to the BUMPER Perimeter. My question is how can you cover all corners with legal BUMPERS if one side of the corner is not part of the BUMPER PERIMIETER?
Good luck with getting clarification. WE decided to go traditional wide body becasue we do not have the patience to deal with non-answers from the GDC on such a mundane subject such as bumpers.
Paul
Ian Curtis
12-01-2009, 11:18
What troubles me is that the bumpers on the internal sides are not really legal BUMPERS becasue they are not mounted to the BUMPER Perimeter. My question is how can you cover all corners with legal BUMPERS if one side of the corner is not part of the BUMPER PERIMIETER?
See GaryVoshol's post below, my interpretation is incorrect
Paul,
My interpretation has always been that an "exterior corner" is one with both both edges (aka sides of the corner) on the BUMPER PERIMETER. This interpretation would be consistent with the images and text in Update #2. I'm working on getting our password to post in the Q&A.
Does this interpretation seem reasonable to anyone else?
GaryVoshol
12-01-2009, 11:24
My interpretation has always been that an "exterior corner" is one with both both edges (aka sides of the corner) on the BUMPER PERIMETER. This interpretation would be consistent with the images and text in Update #2. I'm working on getting our password to post in the Q&A.
Does this interpretation seem reasonable to anyone else?While your interpretation sounds entirely reasonable, it can't be. That's not how BUMPER PERIMETER is defined:BUMPER PERIMETER – the polygon defined by the outer-most set of exterior vertices on the ROBOT (without the BUMPERS or Trailer Hitch attached) that are within the BUMPER ZONE. To determine the BUMPER PERIMETER, wrap a piece of string around the ROBOT at the level of the BUMPER ZONE - the string describes this polygon. The BUMPER PERIMETER may extend up to, but cannot exceed, the maximum ROBOT volume constraints defined in Rule <R11>.Carmen's front corners with the acute frame angles are outermost vertices, and so by definition are on the BUMPER PERIMETER.
An entirely reasonable interpretation, in my estimation, would be to allow 842 to mount non-standard bumpers on the angled pieces such that with the standard BUMPERS on the side the corners are fully protected. The angled pieces would have to count in the robot size and weight. Whether that reasonable (IMO) interpretation will pass, well I guess it's up to them to gamble or not.
And the GDC is fond of saying, "We do not comment on particular robot designs. Here's the rule."
384 huband44
12-01-2009, 11:27
Very awesome looking
Great design work
Chris Fultz
12-01-2009, 11:50
From the rules, it is difficult to tell if this is legal or not.
Either way, though, have you considered this -
If you add the bumpers to these angled sections, you effectively make the hole in your chassis about 6" narrower - each bumper is 2-1/2 - 3" thick, and they would extend into this opening area.
Depending on how wide the opening is now (hard to tell from the picture) it might become very tight for a 9" game piece.
You might actually have a larger opening by having the front of the robot "flat" with 6" bumpers on each side, giving you a 16" wide opening.
I don't know how this fits in with you ball pick-up ideas, but something else to consider.
Ian Curtis
12-01-2009, 12:00
While your interpretation sounds entirely reasonable, it can't be. That's not how BUMPER PERIMETER is defined:Carmen's front corners with the acute frame angles are outermost vertices, and so by definition are on the BUMPER PERIMETER.
An entirely reasonable interpretation, in my estimation, would be to allow 842 to mount non-standard bumpers on the angled pieces such that with the standard BUMPERS on the side the corners are fully protected. The angled pieces would have to count in the robot size and weight. Whether that reasonable (IMO) interpretation will pass, well I guess it's up to them to gamble or not.
And the GDC is fond of saying, "We do not comment on particular robot designs. Here's the rule."
<R08> mentions outermost exterior vertices. The term exterior is never defined, and I always defined it in my head as " both 'sides' of the corner are on the BUMPER PERIMETER."
However, reading the rules and looking at Carl Hayden's robot, I see where my definition falls apart. If their bumpers on the front corner are not exterior vertices, then they have no BUMPER PERIMETER. Yup, I was wrong. :o
JHSmentor
12-01-2009, 12:22
[cdm-description=photo]32317[/cdm-description]
Alright - I didn't pour over all the posts to see if this was asked:
How much does this robot weigh? we have a very similar design but I am really concerned about building it to be robust without weighing a ton.
I think section 8 of update #2 makes it pretty clear that you cannot have bumpers that angles in and have them be considered legal. Notice the square opening in the illustations. If you could angle the bumpers inward on the corners, then the trailer could go in further.
falconmaster
14-01-2009, 10:55
Alright - I didn't pour over all the posts to see if this was asked:
How much does this robot weigh? we have a very similar design but I am really concerned about building it to be robust without weighing a ton.
45 pounds
They don't have to, The rules say you have to cover 75% (I think) of the perimeter of your robot.
but i heard that bumpers have to cover corners.
GaryVoshol
15-01-2009, 20:05
Good news or bad news?
http://forums.usfirst.org/showthread.php?p=24097#post24097
Confirms that both sides of all corners must be protected by BUMPERS.
Doesn't explain how a BUMPER could be legally attached inside the BUMPER PERIMETER.
1708xMr.Roboto
15-01-2009, 20:24
Very Nice Chassis, Although I think It's not legal.. Bumpers must me atleast 6"
Final answer: http://forums.usfirst.org/showthread.php?t=11170
Paul Copioli
16-01-2009, 01:19
Translation: Carmen as shown in the first post is not legal and has no hope of being legal without relocating the angled sides. That stinks.
This is kinda off topic but how did you direct connect your toughbox to your wheel??
and does it have bearings in it?
This is kinda off topic but how did you direct connect your toughbox to your wheel??
and does it have bearings in it?
One way of directly connecting a toughbox to a wheel is a 1/2" keyed hub (see link) for the 1/2" output shaft of the toughbox.
http://andymark.biz/am-0077.html
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