An Integrated Chassis Design Procedure Using the PIDO Technology 2008-01-0884

The study presented in this paper proposes an integrated and automated chassis design process, in which the associated design and analysis, including kinematic design and controller calibration, are sequentially performed through three steps. The first step is an automated kinematic design process that optimizes the hardpoints' coordinates and bush properties. First, ADAMS/Car is employed to evaluate the K&C characteristics by varying arrangements of the hardpoints and bush properties. In addition, a bush stiffness curve is approximated and represented by four parameters, allowing a designer to incorporate the curve as the design variables in the optimization process. Second, an optimization process is employed to automate the calibration of the UCC system modeled by Simulink, which is essential in improving the vehicle's dynamic behavior. The kinematic design information extracted from the ADAMS/Car model is fed into a vehicle model constructed by CarSim that can estimate the vehicle's dynamic behavior. Lastly, both the kinematic design and the controller calibration processes are integrated and automated using the PIDO technology. P.I.A.n.O.(Process Integration, Automation, and Optimization), a design framework tool developed based on the PIDO technology, coordinates the data processing from the kinematic design modules to the UCC calibration modules, and controls the sequence of executing the different modules. In this new kinematic design environment, 14 significant performances are identified to characterize the K&C characteristics. A fish-hook test and a double lane change test are performed. In these tests, the UCC system is calibrated so that the vehicle's dynamic behavior (yaw rate, side slip angle, etc) is stabilized.