A comprehensive review of transient gear-shifting control for automotive transmissions

This article adopts a structured narrative review approach to provide a comprehensive analysis of control-oriented transient gear shifting in automotive transmissions. Transient gear-shift control remains a core challenge in improving the performance of modern automotive powertrain systems. This article first reviews different transmission types, transmission modeling methods, and analyses of the shifting mechanism. Subsequently, by integrating shift process modeling with control methods, the study reorganizes the current transmission shift control into two major categories, namely model-based and model-free control methods. In addition, the study provides a quantitative comparison of different shift-process modeling methods and shift control performances, followed by a discussion of their robustness and engineering applicability. Finally, the major challenges faced by transient shift control are summarized, and the key directions and future trends of transient shift control are identified. The findings of this study provide a comprehensive overview of the current research on transient shift control and can serve as a useful reference for transmission shift calibration and control strategy design.