This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Feedback Control of Synchronizers for Reducing Impacts during Sleeve to Gear Engagement
ISSN: 0148-7191, e-ISSN: 2688-3627
To be published on April 14, 2020 by SAE International in United States
This content contains downloadable datasetsAnnotation ability available
This paper presents a feedback control strategy aimed to reduce noise and wear during gearshifts in conventional and hybrid Dual Clutch Transmissions (DCT and DCTH) and Automated Manual Transmissions (AMT). The control strategy is based on a new dog teeth position sensor developed by China Euro Vehicle Technology AB and existing speed sensors in the transmission. During gear shifting, noise is generated by impacts between the sleeve teeth and the idler gear dog teeth after speed synchronization. Besides noise, these impacts are also responsible for delaying the completion of shift and contribute to wear in the dog teeth, hence reducing the lifespan of the transmission. The presented control strategy controls speed synchronization such that the impact between sleeve and idler gear dog teeth, before the start of torque ramp up, is avoided. Since drag torque is an important factor in speed synchronization, this paper also contains an algorithm to identify friction torque coefficient in the transmission. The identification method ensures that the controller adapts to varying conditions without the need for offline calibration. The control strategy is developed for standard automatic gear shifting operations but minor adaptations in the algorithm also make it capable of handling gear shifts requested by the driver. The output signal of the control strategy is acceleration request on idler gear during speed synchronization. To make controller easier to implement and minimize shift time, the acceleration request only has two values, either maximum value or zero. The control strategy is designed in such a way that it can easily be integrated in the existing transmission control software. By applying the control strategy on a detailed simulation model, it is shown that the impacts during gear engagement are significantly reduced.
CitationPiracha, M., Grauers, A., and Hellsing, J., "Feedback Control of Synchronizers for Reducing Impacts during Sleeve to Gear Engagement," SAE Technical Paper 2020-01-0960, 2020.
Data Sets - Support Documents
|[Unnamed Dataset 1]|
|[Unnamed Dataset 2]|
|[Unnamed Dataset 3]|
|[Unnamed Dataset 4]|
- Piracha, M.Z., Grauers, A., and Hellsing, J. , “Improving Gear Shift Quality in a PHEV DCT with Integrated PMSM,” in CTI Symposium Automotive Transmissions, HEV and EV Drives, Berlin, 2017.
- Tseng, C.-Y. and Yu, C.-H. , “Advanced Shifting Control of Synchronizer Mechanisms for Clutchless Automatic Manual Transmission in an Electric Vehicle,” Mechanism and Machine Theory 84:37-56, 2015.
- Penta, A., Gaidhani, R., Sathiaseelan, S.K., and Warule, P. , “Improvement in Shift Quality in a Multi Speed Gearbox of an Electric Vehicle through Synchronizer Location Optimization,” SAE Technical Paper 2017-01-1596, 2017, doi:https://doi.org/10.4271/2017-01-1596.
- Lu, Z., Chen, H., Wang, L., and Tian, G. , “The Engaging Process Model of Sleeve and Teeth Ring with a Precise, Continuous and Nonlinear Damping Impact Model in Mechanical Transmissions,” SAE Technical Paper 2017-01-2443, 2017, doi:https://doi.org/10.4271/2017-01-2443.
- Chen, H. and Tian, G. , “Modeling and Analysis of Engaging Process of Automated Mechanical Transmissions,” Multibody System Dynamics 37:345-369, 2016.
- Hoshino, H. , “Analysis on Synchronization Mechanism of Transmission,” in 1999 Transmission and Driveline Systems Symposium, 1999.
- Piracha, M.Z., Grauers, A., Barrientos, E., Budacs, H. et al. , “Model Based Control of Synchronizers for Reducing Impacts during Sleeve to Gear Engagement,” SAE Technical Paper 2019-01-1303, 2019, doi:https://doi.org/10.4271/2019-01-1303.
- Math, K.M.H. and Lund, M. , “Drag Torque and Synchronization Modelling in a Dual Clutch Transmission,” Chalmers University of Technology, Gothenburg, Sweden, 2018.
- Walker, P.D. and Zhang, N. , “Engagement and Control of Synchronizer Mechanisms in Dual Clutch Transmissions,” Journal of Mechanical Systems and Signal Processing 26:320-332, 2012.
- Naidu, D.S. , Optimal Cotrol Problems (Pocatello, Idaho: CRC Press, 2003), 293-314.
- Blessing, U.C., Schuerlein, M., and Meissner, J. , “Method for Adapting the Kiss Point,” U.S. Patent US8577573B2, Nov. 05, 2013.
- Cormen, T.H., Leiserson, C.E., Rivest, R.L., and Stein, C. , Introduction to Algorithms (MIT Press, 2009).
- Duan, C. , “Analytical Study of a Dog Clutch in Automatic Transmission Application,” Internation Journal of Passengar Cars, Mechanical Systems 7(3):1155-1162, 2014.