Design & Analysis of Automotive Suspension Components
An automotive first tier supplier required design optimisation of two suspension control arms. FEA was used to maximise the stiffness of the component while minimising weight under loading conditions generated by a previous dynamic analysis.
1. Sports Car Upper Control Arm
Analysis & Design
- Stresses had to be kept below yield
- Longitudinal stiffness was maximised
- Weight was minimised
- Load Input provided by kinematics program
- 5 separate designs were analysed
- Von Mises Stress in MPa
Inertia relief used in conjunction with stress analysis
- Force and moment data was supplied for each end of the arm
- Model must be constrained
- Problem – How do we restrain the arm while ensuring the correct loads are applied to the model?
- One end of arm connected to ground with six degree of freedom spring element
- Inertia relief applied – Translational and rotational accelerations were calculated which result in zero moment and force reaction at base of spring element
Automotive suspension component analysis
2. Off-Road Vehicle Upper Control Arm
Analysis & Design
- Wishbone suspension for off road vehicle
- Three design iterations were performed
- Stress analysis identified the critical area
Design optimisation of an off-road automotive suspension component using FEA
Stiffness Assessment
- Longitudinal and lateral stiffness calculated
- Stiffness of bushes included as spring elements
- Arm loaded in longitudinal direction and displacement at central ball joint measured (Dx).
- Stiffness of arm and bushes determined.
- Youngs modulus of arm increased so arm is effectively rigid. Load applied and displacement measured (Dx rigid).
- Stiffness of bushes determined.
- Stiffness of arm determined
- Process repeated for lateral stiffness
Off-road control arm stiffness analysis
March 2002
