Does anyone have good recommendations with IR sensors?
Are you referring to a beam-break type IR sensor? If so, I’ve had a good experience with these:
Just make sure to power the transmitter side with 5V.
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These worked amazing for us last year. … Until we were in an arena with over heard incandescent light. Then it didn’t work at all.
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It is important to shield them a bit, by either smart placement, or maybe with a cylinder acting as “blinders” to prevent stray light from affecting the receiver end.
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We did. It did nothing. We tried covers, cones, and flaps. But if your venue doesn’t have that, they were amazing.
I dislike these because they take too much setup and can get misaligned. They’re also kind of fragile and need a case… overall I just don’t like them.
If you’re cheap, E18-D80NK from HiLetGo on Amazon is good. It’ll sense game pieces from one side and has an adjustable trip distance. Also easy to mount, though it is bulky. If you want the higher quality stuff, Andymark Q20ND is good, but you need to power it from 12V (such as from a VRM or buck-boost converter). The Q20ND is super reliable though and can last years.
You just have to put the sensor in your CAD, so they’re perfectly aligned from the start.
And there isn’t really any setup, just power the transmitter side with 5V, and connect the receiver side. I connect to a Spark Max, which appears to have built-in pull up resistors, simplifying setup.
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Does anyone have any recommendations for larger range sensors? Taking about 15-21ft. This is to detect if there’s a robot in front of us for the center line auto.
We used a super-cheap (less than $1) boolean IR reflection sensor last year to detect whether we were holding a cube. Something like this.
We also used a slightly more expensive (but still very cheap) analog reflection sensor to help us line up with the feeder station. Something like this.
We also used the first sensor on our gripper prototype this year to stop the Note at the right location.
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It’s not an IR sensor, here’s what I was thinking of buying this year for object sensing for our team:
https://www.digikey.com/short/zq0v004n
In case it doesn’t come up:
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Adafruit KB2040 board with Qwiic connector.
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Adafruit I2C mux
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Adafruit VL53L4CD Time of Flight sensors.
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Qwiic cables to connect everything
The 2040 would communicate with the RIO via Serial over USB. The other option is the Playing With Fusion CAN sensors.
I also bought these to try out because they are so cheap.
Those $1 IR sensors have served us well.
We use these proximity switches. Select the variant (distance range) that you need. Last year they came with straight and right angle headers to solder on. Now headers appear to be an extra you need to buy.
We also use the Sharp IR distance sensors that have been posted on this thread.
I would not use an I2C sensor here. I2C is notoriously broken in the RoboRIO, so you’ll need to use an external controller.
That’s what the Pico and i2c mux is for. Half the idea behind this would be to figure out how to use i2c easily and cheaply in FRC, so that we could potentially use other i2c sensors.
But the plan right now is to use the E18-D80NK and reevaluate based on their performance.
For longer range and detecting a robot I think an ultrasonic distance sensor would work. The Maxbotic one has been in KoP before, so you might have one. AndyMark sells them too.
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Hi, i have a question for a frc robot : do you know if we can connect ir sensors to sparkmax instead of the roborio ?
IR distance sensor (analog) or IR proximity sensor (digital)?
Here’s a breakout board that works. There are a couple of other variations, too.
SparkMax breakout board
Assume using the AdaFruit IR Beam Break sensor mentioned above.
How is the sensor receiver output connected to a SparkMax breakout board?
The 5V, Grnd, and F limit pads?
I don’t remember ever needing pull up resistors on the F or R inputs but you should check to make sure the SparkMax or the breakout board provide them.
Connect to the 5v or 3.3v supply depending on the range of the sensor that you need.
And connect the ground.
Double check all this - my memories are fading.
Thanks - I happened to have a Gadgeteer Breakout board from a million years ago (and no SparkMax breakout board) - the Gadgeteer worked like a charm with the AdaFruit IR beam break sensor.
Way faster trigger than going through the Robrio DIO port.
Less wiring - we are able to get the 5V for both the IR sensor receiver and transmitter side off the Sparkmax.
No need for the pull up resister.