Case Study: FRC 6328's Modular Gusset-and-Tube Methodology

FRC 6328 (Mechanical Advantage) publicly documents its design process, making it a goldmine for an advanced case study. Their public CAD & Design updates and mechanism examples reveal a coherent, repeatable methodology. The quotes below come from 6328's 2022 'CAD & Design Update' build-thread post.

1. Gusset + tube as a design language. 6328 leans heavily on a 'gusset + tube' construction style, having shifted away from sheet-metal construction toward primarily tube-and-gusset since around 2020. The explicit reason, in their words: thanks to the gusset+tube style, 'we should be able to fairly easily adjust portions of the design when something inevitably doesn't work.' 2x1/1x1 aluminum tube joined by laser/waterjet gussets means a geometry change is a new gusset and a re-cut tube — not a redesigned weldment. This is a deliberate bet that the design will change, so make change cheap.

2. Prototype before you finalize. 6328 validates mechanisms with physical prototypes before committing the production CAD ('we had good success with this in our prototype testing'). The detailed model captures a proven mechanism, so it is not wasted on a concept that fails on the field. This inverts the naive 'CAD everything, then build' flow — the risky functional questions are answered first.

3. Mass budget drives decisions. They use Onshape mass properties throughout and design to a target — in 2022 the robot ran ~94.7 lb (without battery/bumpers) with Onshape predicting ~110 lb total, leaving headroom reserved for a climber. Every lightening and material choice is made against that running budget, not retrofitted at the end. This is the discipline that makes FEA-driven lightening actionable: you lighten because you have a number to hit.

4. Iterate explicitly. Their updates describe 'many small (and not so small) iterations which were made before actually manufacturing a first revision' — formal review cycles, not one-and-done. Concrete component choices show up in their writeups (e.g., MAXPlanetary gearboxes on the climber). Their mechanism examples — such as the 2023 A-frame arm pivot with a custom MAXSpline gearbox and dead-axle clamping — are published so other teams can study the exact geometry.

Repeatable practices to steal:

• Default to gusset+tube so geometry changes are cheap re-cuts.
• Prototype the risky functional mechanism before detailed CAD.
• Carry a live mass budget in Onshape and design every part against it.
• Treat the first manufactured revision as the result of multiple reviewed iterations, not the first idea.
• Document and version mechanisms so the team (and future teams) can learn from them.

Adopting even two or three of these moves a program from 'design and hope' toward the evidence-driven, change-tolerant process that separates consistently competitive teams.