Simulation of the shift force for a manual transmission

Abstract

A shift force simulator for manual transmission is developed to estimate the shift force that is transmitted to the driver's hand. In order to develop the simulator, dynamic models of the external linkage, internal linkage, synchronizer and drivetrain are obtained. The synchronizing motion is modelled as seven steps depending on the relative displacement of the sleeve to the ring spring, outer ring chamfer and gear chamfer. The chamfer-to-chamfer contact mechanism is modelled as a linear spring. In addition, a driver model is proposed to simulate the driver's shift lever operation. Based on the dynamic model of each element, a shift force simulator is developed. The simulator calculates the sleeve displacement, cone torque, index torque, sleeve force, shift force and the speed of the input and output shaft. It is found that the shift force by the simulator shows a good correlation with the test results, and it is expected that the shift force simulator developed in this study can be used as a useful design tool to evaluate the shift feeling in the initial design stage.