Anyone reaching into a robot to work on it must first make it incapable of moving or shocking them. Lockout/Tagout (LOTO), governed by OSHA 1910.147 (The Control of Hazardous Energy), is the industrial standard. FRC robots have three hazardous energy sources: electrical (the 12V battery, which per WPILib can briefly supply over 180A and arc at over 500A when fully charged), pneumatic (stored air, with the working regulator set to 60 psi or less and the relief valve set to 125 psi per the pneumatics rules), and mechanical (compressed springs, stretched surgical tubing, raised arms, wound climbers).
Build the procedure as six concrete steps:
- Announce and prepare. The person doing the work calls out 'robot down for service.' Power off the Driver Station so no one can enable.
- Isolate electrical energy. Open the 120A main breaker (Cooper Bussmann 18X series, PN CB285120F) AND physically unplug the battery at the Anderson SB-50 connector. Pulling the SB-50 is the true disconnect; the breaker alone is a switch, not isolation.
- Apply lock + tag. Slip a small padlock or a bright zip-tie tag through the disconnected SB-50 housing or over the breaker so it cannot be reconnected without the worker present. Write who locked it and when on the tag. No one but that person removes it.
- Dissipate stored energy. Open the required manual vent plug (FRC rules require an easily accessible manual vent valve that releases all system pressure without tools) until the storage and working pressure gauges read 0 psi. Lower any raised arm, relieve compressed springs, and discharge stretched tubing. Block any element that could fall.
- Verify zero energy. OSHA 1910.147(d)(6) requires verifying de-energization before work. Try to move the mechanism by hand and confirm gauges read zero. Confirm the robot is truly dead before trusting it; never presume.
- Release. Reverse the steps only when the work is done, tools are clear, and people are warned.
Deliverable - a laminated one-pager taped inside your pit and on the cart, titled 'Robot LOTO,' listing those six steps with your robot's specific gauge and breaker locations. Add a line: 'If you did not lock it, do not unlock it.'
This mirrors the OSHA sequence (notify, shut down, isolate, apply locks, dissipate stored energy, verify) scaled to an FRC robot. It directly prevents the most common shop injuries: a finger in a flywheel that someone re-enabled, or an arm slammed by a pneumatic cylinder during 'quick' pit work.
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Key takeaways
- Real isolation means unplugging the SB-50 connector, not just flipping the 120A breaker.
- Always dissipate pneumatic (vent to 0 psi) and mechanical (springs/tubing/raised arms) energy before reaching in.
- Post a six-step LOTO one-pager and enforce 'if you didn't lock it, don't unlock it.'
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- 5 min readHow to Wire an FRC Robot: A Beginner Electrical GuideA beginner-friendly, accurate guide to wiring an FRC robot: battery, 120A breaker, PDH, roboRIO, radio, CAN bus, and the wire-gauge rules that pass inspection./blogread it
- 9 min readFRC Pneumatics: How to Design, Wire, and Program a Pneumatic SystemComplete FRC pneumatics guide: components, the REV Pneumatic Hub vs PCM, single vs double solenoids, safe wiring, WPILib programming, and the 60/120 psi limits./blogread it
- 7 min readHow to Read the FRC Game Manual (Without Getting Lost)The FRC game manual is the season's official rulebook. Here's how to read the FRC manual without getting lost: structure, rule prefixes, scoring, and Team Updates./blogread it
answer sheet
Lesson quiz
All 3 right completes the lesson. Miss one and only that question comes back, anything you already answered correctly stays banked.
0 of 3 answered
01What is the primary purpose of a Lockout/Tagout (LOTO) procedure on an FRC robot?
02What is the true electrical isolation step when applying LOTO to an FRC robot?
03In a correct LOTO procedure, what does the tag record and who may remove the lock?
Answer every question to submit.
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01 / culture-and-roles
02 / ppe-and-shop-safety
03 / battery-pneumatics-electrical
04 / events-and-program
05 / safety-worked-examples-mini-projects
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