Ding Dong, The Offboard Compressor is Dead

That’s right, the offboard compressor is dead. No longer are offboard compressor systems legal for FRC.

Section 10.9 - Pneumatic System no longer contains a rule detailing the use of an offboard compressor (Section 8.9, R91 in the Power Up manual), nor does it contain a rule permitting offboard compressors (Section 8.9, R86 in the Power Up manual).

Furthermore, all references to an offboard system have been removed: See below the blue box for R86 compared to the blue box for the same rule (R85) in Power Up.

Note also that the robot weight limit has increased to 125lb from 120lb in 2018, and that the weight of an FRC compressor is approximately 3lb with its associated fittings and supporting components. The weight allowance seems to have been borrowed from bumpers.


I don’t read this change to the blue box the same way you do. It makes no mention of whether or not an offboard compressor is legal.

There is no explicit mention of offboard compressors in the rules this year, so it does seem like a potential area for Q&A.


Please refer to 2019 R85 which states that a compressor is required for any pneumatic system.

Without the provisions of 2018 R86 permitting an offboard compressor, disconnecting a compressor after charging removes a compressor from the circuit, in violation of 2019 R85.

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Any idea as to why? Is it because it was harder to regulate what teams had at their pits to fill up with air?

I suspect that it’s in the interest of keeping things moving during competition. We had an offboard last year and several times delays before matches meant they had to let us recharge our system; putting things even further behind.

— a few times we weren’t allowed to recharge and we lost too much pressure waiting. Even if it were allowed I’d try to find weight elsewhere from now on.

I think it just added a level of complexity and confusion to the rules that just didn’t need to be there. The pneumatic rules are already complex enough, we don’t need an extga wrinkle add in.

This change wouldn’t necessarily change that.

G2. ROBOTS must be removed from the FIELD by hand (i.e. no enabling, power, etc.). ROBOTS
will not be re-enabled after the conclusion of the MATCH, nor will teams be permitted to tether to
the ROBOT except in special circumstances (e.g. during TIMEOUTS, after Opening Ceremonies,
before an immediate MATCH replay, etc.) and with the express permission from the FTA or a

Granted, your compressor would be on-board instead of off-board, but in those special circumstances, you would still be able to tether to it to recharge your system, which accounts for the majority of the time in that scenario anyways.

How is this updated rule more complex or confusing?

I was replying to the question of why this rule was added, not that this rule has made it more complex.

Got it - I didn’t follow the reply. New CD problems

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I should have quoted a small piece of it to make it more obvious what I was replying to.

Q10 has confirmed this.

Pneumatic Compressor

According to R86, “compressed air on the ROBOT must be provided by its one onboard compressor only.” Does this mean that teams cannot recharge their air tank via an off-board compressor? Are teams required to have an onboard compressor to use pneumatics this year?
asked a day ago by FRC 1569


Correct. No compressor located off the ROBOT may be connected to the ROBOT’s pneumatic system.

Also note that per Team Update 02, the one compressor is now considered a “motor or actuator” under R34, which implies that (as we already suspected from previous years’ rules) that it must be controlled through the control system, and in particular either the PCM or a relay module. An additional minor update from 2018 to note is that if you would fain eschew the incredibly simple PCM solution, it is now legal to control the compressor through one of the new legal automation direct relays, not just the spike.