Concerns regarding the green paneling/green shirts

[Petey]

Originally Posted by Mouse

Question: I know the tetras are blue and red, but what would you need to seek them out for? Unless maybe from the automated loading dock (in autonomous mode)... but surely you wouldn't make them look for the blue/red on the vision tetras, because it'd be twice the work, right?

You might be able to put your robot into a tetra-seeking mode on the other side of the field.

Or, you might send it to find automated loading docks and load during autonomous.

Or, it might just latch on to another team's blue or red robot. Forget the tetras.

--Petey

[something]

Originally Posted by Petey

Can anyone with a higher knowledge of the workings of the color-sensitive cameras enumerate upon the possible problems that may arise from confusion between the green panelings of the vision goals and green shirts worn by certain teams?

In short, is it plausible that robots might be distracted by certain shades of t-shirt green and be thrown off course?

--Petey

From the brief look at the software (I didn't have a 12v battery charged so I couldn't test anything :-( ) I believe there is someway to create a dead zone that the camera will ignore. The camera can be connected to the computer and used w/ a java application so that colors can be adjusted and matching patterns can be tested. I'm not sure if the data is downloaded into the carmera or if the configuration must be included in the programming

David

[emusteve]

I noticed that there was a section on colors in the FIRST documents page, but the link was broken when I tried to retreive it.

I have to admit that as soon as I saw those green tetras, I could envision 5 bots converging on a certain team's robot and trying to pick it up. :-)
But I think that distractions on the field are simply something we're going to have to take into account and deal with.

Steve

[jgannon]

Originally Posted by Mouse

Question: I know the tetras are blue and red, but what would you need to seek them out for? Unless maybe from the automated loading dock (in autonomous mode)... but surely you wouldn't make them look for the blue/red on the vision tetras, because it'd be twice the work, right?

You'd look for blue or red to find the panel on the ground in front of the loading stations, so you could go over there during autonomous, I presume.

Originally Posted by RbtGal1351

whoah whoah whoah, do we know what SHADE of green we'll be going for??? we didnt get a sample of green in OUR kit! (and it wasnt on the list either).
sooo will we just test w/ some sort of nylon green? what if its different?!!?!

There's documentation on FIRST's website that tells you how to make the appropriate colors. The link is down at the moment, but I think you may be able to get it in one of the other documents. Here's the link in case it comes back:
http://www2.usfirst.org/2005comp/200...int_Colors.PDF

[TheOtherTaylor]

Wouldn't the opponents wearing green shirts be too far away? The bot in the demonstration didn't pick up the shirt till he was really near the bot. It might not have been on before, but do those things have long range?

[Steve Howland]

I don't think it will really be a problem in most cases:

Assume your robot is programmed to begin looking for green as soon as the match starts. To avoid robots running into one another, the bot looking for the tetra (decided upon by the alliance) would probably be in the "B" position (the one a little forward). It would somehow do a sweep of the field looking for green in a few quick seconds, and once it saw something green it would move towards it. For an ally to be the target, it would have to race out and get in the way of the green-sensing robot before it found either vision tetra. For an opponent to be the target, it would need to race across the field and be noticed by the robot before either tetra was seen, which would be pretty tough and clearly the only reason to do that would be interference, which the judges would notice and then penalize the team.

[scottm87]

The vision system has a few different modes. One mode (that most directly applies to the challenge) returns the location and bounding boxes of blobs of color. In the code, it most likely takes these bounding boxes, sorts them by the similarity to the target color, and plots a path depending on the blob's X position or something. It would not be difficult to A) decrease the range of colors or B) apply another level of filtering to determine the height of the blob off the playing field to filter out humans or robots (tall ones at least).

All I am waiting for is someone to pick up a serial CompactFlash interface that are always in Circuit Cellar, and write the frame captures and show a post-match movie .

[Greg Marra]

Regarding using the camera to find the loading stations and/or goals:

You know exactly where these are. The camera would be less important in locating them then it would be the vision tetras. If this new scripting language works as well as it looks like it does, you can very easily dead reckon to exactly where you want to be, sans camera.

[Josh_VK]

This does seem like a large problem. Our Team 773 The Kingsville Kukes have always been green we use green to promote our local Green Houses. this is a large role in our funding. I don't see First telling us we cant use green on our robot. Also are they specifying a paint that the tetras will be done in. it would be a shame to program for weeks to a specific shade of blue and have it not work at competition.

[Jeffrafa]

why don't you go work with the vision system some before you go needlessly arguing over green robots, green shirts, and other distractions. IF in the process of trying to make it work you find that it is easily thrown off, then come here to ask questions about how to correct this problem in detection.

Its something any of us interested in vision will half to test, but just ranting back and fourth about all the possibilities of false detection without ever trying the system is a huge waste of time.

Personally, my guess is the focal range of the camera won't be entirely too large, probably green robots on the other side of the field won't be a problem, and defenitely a crowd in the background won't matter, but i'm anxious to work with the vision system before i commit to saying this is the case.

But i urge you - go try something with it before you sit here on chiefdelphi and needlessly banter back and fourth over it, without experience with the device you have no way of knowing, but by working with it some you can learn an awful lot.

[Rickertsen2]

I Have done some experimentation with the CMU cam and this may very well be a problem with primitive code implementations such as the one provided by FIRST. In order to set the sensors to work reliably in a broad range of light conditions it is necessary to make the tracked color range somewhat large. I have seen some team T-Shirts that pretty closely match the vision tetra colors. The good news is that there are some simple (well relatively) techniques to prevent this by mounting/aiming the camera properly and having a good understanding of the camera's virtual window settings, noise filter settings and how to use them. I feel that FIRST has already babied everyone enough so i am not goign to hold your hand and write your code for you, but i will help with any questions.

[unapiedra]

Originally Posted by Jay H 237

There is no rule against painting or anodizing your robot green (or any other color for that matter).

[EDIT] What I'm referring to per the rule is there's no rule against having a green bot to start with. You just can't change it's color from match to match.

To what rule are you refering to regarding you can start but cannot change to the green color?

[Kyle]

Originally Posted by unapiedra

To what rule are you refering to regarding you can start but cannot change to the green color?

rule R26 in section 5 page 11 it says " No devices are permitted on the robot that are intended to jam or interfere with the operation of the vision system
( i.e changing robot color to confuse opponent's vision system."

[Mark McLeod]

Originally Posted by Mr MOE

Now we (Team 365) need to change our strategy. We were going to build a tetrahedral-shaped robot named TETRA painted MOE green.

Back to the drawing board...

Now that'll be a sight to see.
Wait until your first regional and five other robots converge on MOE, hoist it up and cap a goal with you.

[JBotAlan]

Originally Posted by Kyle

rule R26 in section 5 page 11 it says " No devices are permitted on the robot that are intended to jam or interfere with the operation of the vision system
( i.e changing robot color to confuse opponent's vision system."

As much as I understand your argument, I think it would just be safer to not use any green paint this year. I would hate to get to inspection and have them tell me that I can't put the 'bot on the field because it's green. Everyone will be trying to get their green 'bots through inspection saying that their team colors include green. It would be good to not be at the mercy of the judges.