This paper presents a multidegrees-of-freedom non-linear multibody dynamic model of a vehicle, comprising front and rear suspensions, steering system, road wheels, tyres and vehicle inertia. The model incorporates all sources of compliance, stiffness and damping, all with non-linear characteristics. The vehicle model is created in ADAMS (automatic dynamic analysis of mechanical systems) formulation. The model is used for the purpose of vehicle handling analysis. Simulation runs, in-line with vehicle manoeuvres specified under ISO and British Standards, have been undertaken and reported in the paper.

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This article presents transient handling analysis with a full-vehicle non-linear multi-body dynamic model, having 102 degrees of freedom. A transient cornering manoeuvre, with a constant steer angle and velocity has been undertaken. The effects of aerodynamic lift and drag forces have been included in the simulation tests. The vehicle handling characteristics with and without aerodynamic forces have been compared and various observations made. The aerodynamic forces have been predicted by a k-1 model solution of the Navier-Stokes equations for turbulent flow. The numerical predictions for the evaluation of aerodynamic lift coefficient agrees well with the scaled-down air tunnel experimental work, using hot-wire anemometry.

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This paper presents a detailed theoretical and experimental investigation for ride comfort evaluation at different vehicle speeds. For the purpose of ride comfort evaluation, a quarter car model with two degrees of freedom has been developed. For realistic investigation, the equivalent characteristics of suspension stiffness and the shock absorber characteristics are calculated and incorporated to simulation. Using available quarter car test rig for single independent front suspension, that embodies sprung mass, unsprung mass, suspension system and tire. An excitation of sinusoidal road profiles with constant amplitude is imposed via eccentric wheel that represents the road profiles. The experimental results of sprung mass and unsprung mass accelerations due to road excitation are measured, recorded and processed. A validation of the theoretical results with experimental results has been carried out at different speeds. Good agreement has been obtained when using the equivalent suspension stiffness and damping coefficient as input parameters to quarter car model representing the independent front suspension.

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