Modelling and simulation of detailed vehicle dynamics for development of innovative powertrains

Abstract

Simulation with a basic representation of longitudinal vehicle dynamics is known to be sufficient for initial powertrain development activities related to efficiency and emissions such as concept application, optimal sizing, analysing the effects of physical and functional changes and also for defining basic control laws. However, when it comes to comprehensive analysis for efficiency improvement, minimizing instantaneous emission peaks or studying the impact of the new concepts on road safety, drivability and performance, the significance of detailed vehicle dynamics cannot be ignored. The work presented in this article defines a longitudinal vehicle dynamic modelling approach considering important characteristics such as the influence of normal load transfer on the varying grip of the front and rear wheels, the effect of wheel slip, and a complete representation of resistances encountered against vehicle motion with the objective of taking the analysis even closer to the actual driving conditions. The behaviour of this combined simulation platform under normal and extreme driving conditions seems to precisely follow the real scenario. This approach is a first step towards future analysis, optimization and controls development for improving transient powertrain aspects such as maximizing regenerative braking under heavy deceleration or optimizing road charging in P4 parallel hybrid architecture by managing wheel slip losses.

Investigation of Different Communication Topologies for Cooperative Adaptive Cruise Control Systems

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A discussion on design fires for high-speed railway train cars

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