The Unwritten Rules

These aren't in any game manual or textbook. They're the things every experienced FRC member knows, usually because someone on their team learned them the hard way. Most of them are obvious in hindsight. Almost none of them are obvious the first time.

On Design

Keep it simple. Every part you add is a part that can break, a part that adds weight, and a part that takes time to design and build. The simplest mechanism that does the job is almost always the right one. Complexity is not a sign of good engineering. It is usually a sign that something wasn't thought through all the way.

• Steal from the best, invent the rest. There is almost no mechanical problem in FRC that a top team hasn't already solved. Watch robot reveals. Study Open Alliance build threads. Copy what works. Save your creativity for the things that are genuinely new.

• Inside the frame perimeter: bulletproof. Outside: flexible. Anything that extends past your frame perimeter will get hit. Design those parts to survive impact or to fail gracefully without taking the rest of the robot with them. Polycarb and compliant materials outside the perimeter absorb hits that would crack aluminum. Rigid and robust inside, forgiving outside.

• If it's not constrained, it will move. Every degree of freedom you don't intentionally lock down is a degree of freedom the robot will find during a match. Check every joint, every shaft, every plate. If something can rotate, slide, or flex when it shouldn't, it eventually will.

• Design for the worst driver, not the best one. The robot should be hard to break even when driven aggressively, under stress, or inaccurately. Your driver is running on adrenaline at competition and will make mistakes. If the robot requires gentle handling to survive, it will not survive.

• Your robot will get hit harder than you think. A 115 lb robot at full swerve speed has a lot of momentum. Design for impact. If something looks like it'll survive in the shop, it might not survive being rammed on the field.

On Fasteners and Failure

Loctite everything that vibrates. But never near polycarb or plastic threads. Blue Loctite on any bolt that isn't using a nylock nut. If a bolt can vibrate loose, it will. However, Loctite will craze and crack polycarbonate on contact. Never apply it near plastic parts, and never use it in a plastic-threaded hole.

• Never cantilever. Always support shafts, mechanisms, and heavy components from both sides. A single support point doesn't hold something in place, it creates a pivot point. The only time a cantilevered shaft is acceptable is when it's intentionally dead-axle and loaded appropriately.

Why most FRC failures are bending failures

When a mechanism arm extends, every bit of weight at the end creates a moment (a rotational force) at the base. The longer the arm and the heavier the load, the larger that moment, and the larger the stress on the support structure.

A bolt in tension holding a plate flat is in a favorable load case. A bolt being pried away from a surface by a cantilevered load is in a much worse one. This is why well-designed mechanisms keep pivots close to loads, use triangulated structure, and avoid long unsupported spans.

On Belts, Chain, and Hardware

Belts over chain by default. Lighter, quieter, no lubrication, no stretch over time. Use chain only when the torque load genuinely requires it (pivot arms, climbers). Most mechanisms that could be either should be belt.

Steel sprockets only. Aluminum sprockets strip teeth under real chain loads. This is not theoretical. The team sheared aluminum sprocket teeth in 2023 under pivot arm load. Steel sprockets on every chain run, no exceptions.

On Competition

• Spare everything critical. If a part can break and would take you out of a match, bring a spare. Pre-cut, pre-drilled, and ready to install. A spare that needs to be modified in the pit is barely better than no spare.

• Test on carpet. The robot behaves differently on carpet than on tile or concrete. Traction, turning radius, intake behavior, and swerve tuning all change. If you can, practice on the same type of carpet used at competition before your first event.

• Label everything. Wires, subsystem modules, spare parts bins. At competition you are tired, stressed, and working fast. Labels save time and prevent the kind of mistake that costs you a match.

Deburr every edge. Sharp aluminum edges cut wires, cut fingers, and can fail inspection. Every machined or cut part gets deburred before it goes on the robot. This is not optional.

• Duct tape and zip ties are temporary. They will absolutely save you at competition in an emergency. Use them freely for quick fixes. Replace them with proper fastening when you're back in the shop. A robot that ships to competition covered in zip ties and tape is a robot that wasn't finished.