Mathematical Model and Simulation for Improving Brake, Bump and Roll Steers in Light Commercial Vehicle (LCV)

Abstract

Due to recent infrastructural developments and emerging competitive automotive market in India, there is seen a huge shift in customer demand and vehicle drivability pattern for small commercial vehicles. Various factors contributing to driver’s fatigue include driver negligence, inappropriate driving habits and vehicle inherent design error due to which a driver is forced to make frequent steering wheel corrections so as to make the vehicle run in a straight line. Thus, optimization of steering, suspension and front axle geometry becomes important for improving the overall vehicle drivability and reducing the driver fatigue. Mentioned herewith are the major kinematic characteristics in a vehicle which plays vital role for ensuring vehicle improved drivability – Brake steer, Bump steer, Roll steer and Ackerman Geometry. As on today, the above analysis for deriving optimized linkages hard points for steering, suspension and front axle system are done in customized Multi body dynamics software’s like ADAMS/Trucksim. Although the derived hard points in such MBD software’s are precise yet there are several drawbacks in such approach like increase in overall project time plan, mainly due to the vehicle packaging issues for the proposed hard points and also these software customized license and AMC are quite high which increases the overall operating cost of a project. In this paper, an approach has been developed so as to derive these linkages hard points through mathematical calculation and kinematic simulation model in product design Catia platform itself. This helps the designer to derive the optimized hard points of linkages for “n” number of design iterations at the concept stage itself. Thus, this design methodology saves not only on the project design cost but also it reduces the overall product design lifecycle and gives the respective designer to choose the optimum hard point based upon the vehicle packaging feasibility Brake steer, Bump steer, Roll steer, Catia 2D layout, Camber, TCD, Ackermann error.