Gearshift control system development for direct-drive automated manual transmission based on a novel electromagnetic actuator

A novel gearshift system which comprises a 2 degree-of-freedom electromagnetic actuator is introduced to simplify the structure of gearshift system of automated manual transmission (AMT), increase transmission efficiency and improve shift quality. The working principle and characteristics of the actuator are analyzed. The gearshift process is divided into the non-synchronization and the synchronization phase. Extended state observer (ESO) based inverse system method (ISM) and active disturbance rejection controller (ADRC) are designed for the two processes respectively. ISM can eliminate the nonlinearity of the actuator and ESO can estimate and compensate the uncertainties, parameter variations and external disturbances. ADRC is adopted to improve the tracking accuracy of the synchronization process. Comparative simulations and experimental results demonstrate the effectiveness of the proposed control method, and good gearshift performance has been achieved. Combined with the new designed control strategy, the novel gearshift system provides a new solution for AMT applications.