Adams Assignments – Problem 5 – Compliance

Brake steer

Brake steer: -0.096deg/m

Suspension toes out under braking.

Traction steer

Traction steer: 0.078deg/m

Suspension toes in under traction force.

Longitudinal wheel center recession under traction

Longitudinal wheel center recession under traction force: 0.493mm/KN

Longitudinal wheel center recession under braking force

Longitudinal wheel center recession under braking force: -0.487mm/KN

Longitudinal wheel center recession under braking and traction forces are different because the braking force is applied at the tire contact patch and the traction force is applied at the wheel center.

Lateral force compliance steer

Lateral force compliance steer: -0.167deg/KN

It's an oversteer effect as suspension toes out when the force is applied.

Lateral force camber compliance

Lateral force camber compliance: -0.40deg/KN

It's an understeer effect as the suspension gains negative camber when force is applied.

Bump steer

Parallel wheel analysis was performed on the rear multi-link suspension to obtain bump steer.

Bump steer: -2.5deg/m

It's an oversteer effect as the suspension toes out on the bump.

2. Tuning

Parallel wheel analysis was performed on the rear multi-link suspension and hardpoints were modified to obtain the target bump steer.

Bump steer (Baseline): -2.5deg/m

Bump steer (Target): 2.6deg/m

It's an understeer effect as the suspension toes in on the bump.

Lateral force camber compliance: 0.42deg/KN

Target lateral force camber compliance is achieved by modifying the trailing link inner hardpoint.