Anti-Roll Bar System Design

CAD, FEA, and Hand Calculations

Designed the rear anti-roll bar (ARB) system to meet specific roll stiffness targets while maintaining adjustability for track tuning.

Design Features

  • Adjustable Geometry: Implemented a 3-lever arm configuration. This allows the team to mechanically adjust the motion ratio and tune the car’s handling balance.
  • Materials: Selected AISI 4130 steel for the main torsion bar (5/8” OD, 0.028” wall) and welded blades to maximize fatigue life.
  • Mounting: Designed custom 6061-T6 aluminum housings with Delrin bushings to minimize friction and wear during operation.

Validation

I validated the design using both analytical methods and Finite Element Analysis (FEA).

  • Hand Calculations: Modeled torsion and bending moments using a spreadsheet calculator. Calculated a Safety Factor (FOS) of 1.34 based on the material yield strength.
  • FEA Simulation: Performed a Static Structural analysis in Ansys. The simulation verified the hand calculations with a comparable minimum FOS of 1.58.
Left: Analytical model calculating shear, bending moment, and FOS. Right: Ansys Static Structural analysis confirming the safety factor.