I modeled the following templates in ADAMS/Car Template Builder:
- Front solid drive axle
- Read solid drive axle
- Front pitman steering
- Front antiroll bar
- Rear antiroll bar
- Body
- Extra load on the body
- Tire and wheel
The subsystems and whole vehicle model were created by the above templates in ADAMS/Car Standard Interface. The following methods were utilized to correlate and validate the model:
- Comparing the Parallel Wheel Travel results with K&C test for front and rear suspension subsystems
- Comparing the steering wheel rotation results with the real test reports
- Employing COG test and defining the locations in whole vehicle model for handling test maneuvers.
- Employing vehicle moment of inertia in whole vehicle model for handling test maneuvers.
The following simulations were performed to evaluate the axle performance:
- Parallel wheel travel to check bump steer, camber steer etc.
- Opposite wheel travel to check the minimum torsional stiffness, roll steer etc.
- Steering simulation to check parking effort and the minimum power for steering box.
- Constant Radius Cornering test to evaluate the understeering characteristics.
- Lane change transient maneuver to evaluate the transient characteristics of lateral dynamic.
- Steering with release test to check steering return-ability
- Simulations concerning turn radius
To determine the fatigue life of the steering subsystems, I employed some useful simulations and test procedures including turn fully right, turn fully left and figure of 8.
The following specification of the vehicle model were improved and optimized:
- Bump steer was decreased to smallest value
- Camber was nearly unchanged during bump
- Better operation in roll resulted in better understeering
- Caster alteration was increase to compensate the return-ability of the steering.
- Scrub radius, Caster arm and many more suspension characteristics were improved.
To optimize the dynamic performance of front and rear axle, I successfully accomplished different DOE studies using ADAMS/Insight by defining some adequate objectives in the suspension simulation.