Stability analysis and development of gear shift patterns for an eight speed automatic transmission vehicle

Abstract

The increasing stringency of exhaust emission regulations, as well as the rising index of carbon dioxide emissions from the road transport, has driven auto manufacturers and designers to develop solutions for even more efficient vehicles, with well-designed vehicle transmission and gear shift patterns among the alternative approaches used. The current article proposes a design method for developing an appropriate gear ratio set and gear shift patterns for an eight-speed automatic transmission. The BMW M4 Eight speed transmission model was developed using the MATLAB/Simulink platform, and the results were validated using experiment data. The effectiveness of the previously chosen gear ratio set and gear shift patterns was then assessed using a eight-speed transmission model based on the validated six speed transmission model. Based on a mathematical simulation approach, this article presents a novel microscopic model to illustrate the traffic phenomenon. The stability of the proposed model is investigated using the perturbation technique in order to analyze it and determine its stability conditions. The mathematical experimental tests were carried out, and the results reveal that the proposed model is valid. Patterns for sport mode, eco mode, and an accomplished by two modes were analyzed and the results.