What sensors are used to detect the hot LED lights on the FRC field?

[Ramtech59]

My team and I are trying to use sensors on our robot to help us in autonomous, but we were wondering which sensor could be used to detect the hot LED lights on the field and where we could buy them.

[cglrcng]

Look in your kit of parts received on kickoff day for the grey section of light reflective tape, hook up the camera properly so you can see the image on your drivers station screen, and attach a light source near the lens of the camera, then aim it directly at the reflective tape (there are different sections of that type of tape on each alliance wall including the hot side flip boxes), look at the image on your screen (the tape will reflect back the light based on the color of the light source you actually aim at it). Then read up on programming a bunch.

Good Luck!

[DonRotolo]

Originally Posted by Ramtech59

My team and I are trying to use sensors on our robot to help us in autonomous, but we were wondering which sensor could be used to detect the hot LED lights on the field and where we could buy them.

We are using the Axis camera to detect the yellow LEDs surrounding the high goal during autonomous.

[Ramtech59]

thanks for the replies, me and my team appreciate the help given to us.

[tr6scott]

Originally Posted by DonRotolo

We are using the Axis camera to detect the yellow LEDs surrounding the high goal during autonomous.

Don,

I was thinking of doing this too, did you buy the lights the field uses, or did you have access to a field that did? Once the bot is in the bag, we are working on hot goal detection, anything you can share?

[Lightfoot26]

We are using a photoelectric IR sensor. We will dead reckon before the match, it acts as a digital input and sends true when it sees the retro reflective tape. False if otherwise, process of elimination... If False then 1 goal is hot, if true, the other is hot. Simple elegant solution... If we don't have to use vision... we find every way not to. although some years we can't get around it... (i.e. 2012).

[Bpk9p4]

How are you using the photoelectric sensor to detect if the goal is hot or not? Also how can you tell if you are detecting the vertical strip vs the actual hot goal?

[Bruceb]

Yes, remember there is an always "hot" reflective vertical strip adjacent to the variable horizontal one.

[NotInControl]

Originally Posted by Lightfoot26

We are using a photoelectric IR sensor. We will dead reckon before the match, it acts as a digital input and sends true when it sees the retro reflective tape. False if otherwise, process of elimination... If False then 1 goal is hot, if true, the other is hot. Simple elegant solution... If we don't have to use vision... we find every way not to. although some years we can't get around it... (i.e. 2012).

I am interested in this as well.

What sensor are you using? The hot goal is determined by a vertical and horizontal rectagle being present.

Based on section 2.2.4 of the game manual "Before the MATCH starts and throughout TELEOP, both dynamic VISION TARGETS are positioned such that the the reflective material faces the FIELD."


So before a match, both left and right sides are "Hot". When Autonomous starts, one side has their horizontal bar rotated away, so that indicates it is notHot, and the other side is.

How can you determine the presents of both horizontal and vertical targets exisit with an IR sensor? I believe the IR sensor will at least always see the Vertical Bar and return true, no?

-Kevin

[Caleb Sykes]

Originally Posted by Ramtech59

My team and I are trying to use sensors on our robot to help us in autonomous, but we were wondering which sensor could be used to detect the hot LED lights on the field and where we could buy them.

sensor we are using: human eyeballs...
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By using a Kinect on the driver's side during AUTO.

Now the question is, how many posts there will be before someone tells me that this is illegal. My guess: 4

[DjScribbles]

Originally Posted by tr6scott

Don,

I was thinking of doing this too, did you buy the lights the field uses, or did you have access to a field that did? Once the bot is in the bag, we are working on hot goal detection, anything you can share?

I'm also quite curious about this. It had crossed my mind, but I didn't get any further than that with the idea.

Are the individual LEDs close enough together and bright enough that they don't simply appear as individual spots of light without making the filtering stage too permissive?

[NotInControl]

Originally Posted by inkling16

sensor we are using: human eyeballs...
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.
.
.
.
By using a Kinect on the driver's side during AUTO.

Now the question is, how many posts there will be before someone tells me that this is illegal. My guess: 4

I believe what you are attemping to do IS perfectly legal.

[brennonbrimhall]

Originally Posted by NotInControl

I believe what you are attemping to do IS perfectly legal.

Confirmed in Q&A #55.

[DonRotolo]

Originally Posted by tr6scott

I was thinking of doing this too, did you buy the lights the field uses, or did you have access to a field that did?

No, we got LEDS from SuperBrightLEDs.com, they were a lot less expensive. Also see my PM to you Scott.

Originally Posted by DjScribbles

Are the individual LEDs close enough together and bright enough that they don't simply appear as individual spots of light without making the filtering stage too permissive?

They're 2 or 3 inches apart, but the camera sees them as a 'blob' and not pinpoints of yellow. I don't have the details, but they tell me that the filter is relatively permissive because it's not expected to tell us anything more than "Yep the LEDs are on". We're not using the LEDs for aiming or anything like that, just "Is it hot?"

[Joe Ross]

Originally Posted by DonRotolo

No, we got LEDS from SuperBrightLEDs.com, they were a lot less expensive. Also see my PM to you Scott.
They're 2 or 3 inches apart, but the camera sees them as a 'blob' and not pinpoints of yellow. I don't have the details, but they tell me that the filter is relatively permissive because it's not expected to tell us anything more than "Yep the LEDs are on". We're not using the LEDs for aiming or anything like that, just "Is it hot?"

They should be sure to test with these images: http://firstforge.wpi.edu/sf/go/proj..._vision_images