Presentation of a Mathematical Model for Preparing Vehicles’ Gearbox Ratio on the base of Functional Condition of Vehicle on Road

Efficiency and durability of automobiles gearbox in different functioning conditions, have special importance in automotive industry. This condition depends on some factors such as power, entrance torque, different combinations of torque and output RPM. In addition to mentioned conditions, also it depends on different conditions of road. So in this study, a codified system for evaluating the performance of automobiles gearbox has been provided. To codify this system, all conditions such as road condition, automobile type, engine power and other cases were considered. Dynamics of automobile action, its equations and exerted forces on automobile were studied. In terms of performance view, to choose more efficient gearbox, at first effective performance indices that play important role in selecting a suitable power transmission system were introduced and modeled then mathematical model was codified, the output of this model is the ratio of automobile gearbox gears. Finally an algorithm for optimizing gained gears ratio is offered.

Keywords:

gearbox , gear ratio , fatigue life