System temperature

Hi all
Just a general question
What are the usual temperatures for the control system to run at? I don’t want to melt a brand new robots control system. Our new testbed robot will have one enclosed deck in it,that will be the control system deck. The second wil be exposed to the air, so no need for active coolant systems.

Do I even need active coolant? Fans are all we have, considering we will be mounting some form of compressor to the robot inside the control deck.

In our experience, the compressor is going to be the main source of heat issues while testing. It’s rare for a compressor to overheat over the course of a ~2 minute match, however when testing it can become a big issue if it starts melting things. Our team keeps lots of compressed air cans in stock because if you hold the canister upside down and spray the compressor it’ll have an extreme cooling effect.

If your “control system deck” is an enclosure that contains both the compressor and the roboRIO, you’ll definitely want a fan to provide active cooling.

If I was building it, I’d have a small 40mm fan on the compressor heat sink, and a larger 80 or 120mm fan on the enclosure. Make sure your exit has the same area as the opening for the fan.

You can’t go wrong by having some active cooling present.

The roborio spec says local ambient temperature limit is 40C (104F); that’s pretty standard for electronics.

A small fan to provide some nominal air exchange should be fine. “Enclosed” can mean a lot of things, you’ll want some vent holes for cross flow so that you’re actually moving all the air with no dead spaces.

Depends whether you overclock ir

The compressor can get VERY hot.

I would personally not mount the compressor inside an enclosure if at all possible.

I wouldn’t have an issue with the rest of the electronics, but I would introduce a small cooling fan to circulate air inside, especially near the motor controllers.

After some consideration we decided to go with 1 120 mm fan blowing back to front across the control board, and to mount the compressor externally. We also chose to utilize the talon Sr fan mounts ( yes those two screw holes are for mounting a fan, even though you shouldn’t need one for the sr ) and mounted some small fans on those. The dam thing sounds like a jet engine taking off when it’s on, but the amount of airflow is perfect. We also mounted a mesh grate over the 120 mm seeing as it’s blowing from the outside in. Might get some debris flying out of the robot. Also mainly because i don’t want to get my knuckles scraped off ( I hate those victor 888s for this specific reason )

The only question I have is what happens if we do overheat the compressor? This testbed tends to be on for long periods of time and in operation.

The tubing directly connected to the compressor output will eventually deform and pop out of the fitting. If you have the old Thomas compressor, it’d probably be a better fit for this as it’s rated for a higher duty cycle.

“Pop” isn’t the right word, it’s more like “bang”. It sounded like a .22 going off when this happened during Ultimate Ascent practice.

Make sure your compressor is not enclosed. We tested the temperature of a compressor after 2 hours of drive practice (roughly 15-20% duty cycle), and the compressor had reached about 200 degrees. Motor controllers, depending on which type you use, can get pretty warm under heavy loads(i.e. drivetrain motors during defense). Otherwise, nothing else will get particularly warm, but always play it safe.

The only question I have is what happens if we do overheat the compressor? This testbed tends to be on for long periods of time and in operation.

The compressor we did this test on, although it still works, is louder and does not fill the pneumatic system as quickly. Although it won’t necessarily cause a catastrophic failure, it can cause permanent damage to the compressor.

We’ve seen this happen on a few of the 90C’s we have, if you smell burning it’s probably a good idea to stop :slight_smile:

The robots are shooting at us! Gahh
Wonder how much noise a tank makes when it " spontaneously depressurizes"

Our current robot has this same setup where the compressor is on the bottom level of the robot with lexan on top and bottom of the robot. The only difference is that this one has a fan blowing directly onto the compressor.