Knuckle Mounting Brackets, Raghav Singh

The front knuckle mounts to the upper and lower control arms through brackets, and those brackets are where the whole corner's load path passes into the knuckle. I designed those brackets and ran the structural validation for the corner. To be clear about scope: the knuckle body and the control arms themselves were designed by other members of the team; the mounting brackets and the FEA are mine.

What I designed

The upper and lower control-arm mounting brackets on the knuckle. These are the load-transfer joints between the knuckle and the control arms. The design driver was structural integrity at that interface: we were fighting a weight budget across the car, but we had margin to spend on these specific parts, so I sized them as the most robust sections of the assembly at the bracket-to-control-arm connection, where the corner's load concentrates.

Knuckle assembly, vertical bump, stress at the mounting brackets — FIG 1 · Vertical bump. Peak stress sits at the lower control-arm mounting bracket, 56 MPa, which confirmed the brackets were the right place to add material.

Knuckle assembly, braking, stress at the bearing bore — FIG 2 · Braking. The peak moves off the brackets to the wheel bearing bore, 122 MPa: the load path shifts with the load case.

How I validated the design

I ran the corner under three load cases, not one. Vertical bump, braking, and combined braking-plus-bump. Under vertical bump the peak lands on the lower mounting bracket at 56 MPa, which is exactly why I made the brackets the thickest sections. But under braking the peak migrates to the wheel bearing bore at 122 MPa. The critical feature is not fixed; it moves with the load path, which is why a single load case would have been misleading.
The load path, not just the magnitude, drove the design. The combined braking case applies about half the vertical load of a pure bump yet produces nearly twice the stress, because a longitudinal force acts through a much longer moment arm about the suspension pickups. Designing the brackets meant sizing them for where and how that load actually enters the knuckle.
I confirmed the numbers were real, not mesh artifacts. The knuckle peak sits at a bolted, constrained hole, exactly where a fixed-constraint singularity would show up. I ran a mesh convergence check: refining from 13,484 to 20,672 elements moved the peak by only 1.4% and did not move its location, so the stress is resolved and reportable rather than a numerical artifact.

Analysis conditions
Material	6061-T6 aluminum, yield 275 MPa
Corner load	552 N static, 3g bump = 1,656 N at the wheel bearing bore
Constraints	Bolt connectors at the UCA/LCA joints; bracket faces fixed
Convergence	57.0 to 56.2 MPa across a 53% element increase (−1.4%)
Software	SOLIDWORKS Simulation

Tools & techniques

SOLIDWORKS + Simulation for the bracket modeling and the structural runs.
Bolt connectors at the joints rather than modeling every fastener, which keeps the load transfer realistic without meshing thread detail.
Mesh convergence as a standard check before trusting any peak that lands on a constraint.