Current research of automatic transmission(AT)mainly focuses on the improvement of driving performance,and configuration innovation is one of the main research directions.However,finding new configurations of ATs is o...Current research of automatic transmission(AT)mainly focuses on the improvement of driving performance,and configuration innovation is one of the main research directions.However,finding new configurations of ATs is one of the main limitations of configuration innovation.In the present study,epicyclic gear trains(EGTs)are applied to investigate mechanisms of 9-speed ATs.Then four kinematic configurations are proposed for automatic transitions.In order to evaluate the performance of proposed mechanisms,the lever analogy method is applied to conduct kinematic and mechanical analyses.The power flow analysis is conducted,and then transmission efficiencies are calculated based on the torque method.The comparative analysis between the proposed and existing mechanisms is carried out where obtained results show that proposed mechanisms have reasonable performance and can be used in ATs.The prototype of an AT is manufactured and the speed test is conducted,which proves the accuracy of analysis and the feasibility of proposed mechanisms.展开更多
In order to realize the computer aided design of AT shifting element schemes, a mathematical model of shifting element schemes which can be easily identified by computers was built. Taking the transmission ratio seque...In order to realize the computer aided design of AT shifting element schemes, a mathematical model of shifting element schemes which can be easily identified by computers was built. Taking the transmission ratio sequence as an optimization objective and simple shifting logic between adjacent gears through operating only one shifting element as a constraint condition, a fitness function of shifting element schemes was proposed. ZF-8AT shifting element schemes were optimized based on GA work-box of MATLAB, and the feasibility of the optimization algorithm was verified.展开更多
基金Supported by National Natural Science Foundation of China(Grant Nos.51975544,51675495).
文摘Current research of automatic transmission(AT)mainly focuses on the improvement of driving performance,and configuration innovation is one of the main research directions.However,finding new configurations of ATs is one of the main limitations of configuration innovation.In the present study,epicyclic gear trains(EGTs)are applied to investigate mechanisms of 9-speed ATs.Then four kinematic configurations are proposed for automatic transitions.In order to evaluate the performance of proposed mechanisms,the lever analogy method is applied to conduct kinematic and mechanical analyses.The power flow analysis is conducted,and then transmission efficiencies are calculated based on the torque method.The comparative analysis between the proposed and existing mechanisms is carried out where obtained results show that proposed mechanisms have reasonable performance and can be used in ATs.The prototype of an AT is manufactured and the speed test is conducted,which proves the accuracy of analysis and the feasibility of proposed mechanisms.
基金Project(2011BAG09B00)supported by the National Science and Technology Support Program,China
文摘In order to realize the computer aided design of AT shifting element schemes, a mathematical model of shifting element schemes which can be easily identified by computers was built. Taking the transmission ratio sequence as an optimization objective and simple shifting logic between adjacent gears through operating only one shifting element as a constraint condition, a fitness function of shifting element schemes was proposed. ZF-8AT shifting element schemes were optimized based on GA work-box of MATLAB, and the feasibility of the optimization algorithm was verified.
