Influence of tire inflation pressure on vehicle dynamics and handling performance

Tire inflation pressure affects both tire longitudinal andlateral stiffness and thus may impose a considerable influence onvehicle dynamics and handling performance. This paper presentsa comprehensive study revealing the effects of tire pressurevariations and their distribution among four tires on vehicledynamics and handling performance. An extended MagicFormula tire model and a modified UniTire model involving tireinflation pressure are employed to describe the tire longitudinaland lateral forces, respectively. Two groups of vehiclemaneuvers are simulated in CarSim: a single lane changemaneuver with braking and a double lane change maneuver, toexhibit the effects of tire inflation pressure. Various tire pressurevariations including all four tires at same and different pressuresare examined. A vehicle dynamics, lateral motion stability index,and driver steering workload are utilized to quantify theinfluence of tire pressure variations and distributions. Analyseson the simulation results indicate that: 1) a front tire pressurereduction induces vehicle understeering tendency and a largersteering angle; 2) a rear tire pressure reduction causesoversteering characteristics and a sacrifice on vehicle stabilitywith a larger vehicle sideslip angle; 3) all-tire inflation pressuredecrease will increase driver's steering workload; and 4) lowerrear-tire inflation pressure can promote the combinedperformance of vehicle path-tracking and driver's steeringworkload.