Engineering Projects
Designing a rear upright
for a Formula Student car
An eight-month topology-optimisation study that produced a wheel-upright 10.4% lighter and with more than twice the structural headroom of the part it replaced on Queen Mary's 2024 electric Formula Student car.
vs. QMFS 2024 EV
headroom gained
mass per corner
simulated load cases
The brief
The upright is the single structural transition between a wheel and the suspension. Cornering, braking and traction loads flow through it from the tyre contact patch into the chassis; anything else it does is incidental. Yielding, excess deflection or fracture means lost wheel alignment, lost suspension geometry, and — by extension — a compromised car.
Queen Mary's 2024 EV car carried an upright that worked, but conservatively: 0.67 kg per corner. When re-analysed under a combined cornering & braking case it had never originally been simulated against, its minimum factor of safety slipped below 2.0. The brief, then: lighter, and safer, at the same time.
The approach
Every design decision was driven by analysis. Suspension hard-points — caster, camber, toe, wishbone pickups, caliper interfaces — were drawn from the literature (Milliken & Milliken, Goodman, Saurabh et al.) and then frozen in CAD so the topology optimiser couldn't move them. A solid block of Al 7075-T6 was sized to encompass that frozen geometry, then handed to TOSCA inside Abaqus CAE for 15 design cycles against six load cases:
- LC.01Pure cornering
- LC.02Pure acceleration
- LC.03Pure bump (3.5 g)
- LC.04Pure braking
- LC.05Cornering + acceleration
- LC.06Cornering + braking
The output of design cycle 15 was exported as a VRML mesh, re-imported into SolidWorks and used as a sculptor's reference to redraw the part by hand. Each redraw was sent back through the same FEA pipeline — seven hand iterations in total before a version cleared the FoS ≥ 2.0 threshold while still undercutting the 2024 part on mass.
The result
Iteration 7 is the design that ships. 0.60 kg, FoSmin 2.14, machinable on 3-axis CNC in Al 7075-T6. Against the 2024 part it saves 70 g of unsprung mass per corner — 280 g across the car — while leaving an extra 7% of stress headroom for next season's higher cornering speeds.
The route to Iteration 8 is already mapped: fillet the depth-wise edges (5-axis CNC required), shift the lower design region's mass closer to the caliper interface, and constrain TOSCA with an early-stop on FoS ≤ 2.0 so the optimiser can run further before any hand-redraw begins.