This content is not included in your SAE MOBILUS subscription, or you are not logged in.
Model Based Control of Synchronizers for Reducing Impacts during Sleeve to Gear Engagement
ISSN: 0148-7191, e-ISSN: 2688-3627
Published April 2, 2019 by SAE International in United States
This content contains downloadable datasetsAnnotation ability available
This paper presents a model based 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 newly developed dog teeth position sensor layout at China Euro Vehicle Technology AB (CEVT), a detailed simulation model for gear engagement and already existing speed sensors in the transmission. The details of dog teeth position sensor and simulation model are also presented in this paper. During gear shifting, noise is generated because of 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 simulation model for gear engagement can simulate these impacts. Based on the simulation model and optimal control theory, an ideal dog teeth position trajectory is formulated that avoids the impact between sleeve and idler gear dog teeth, before the start of torque ramp up. The open loop strategy then controls the synchronization torque in the beginning of speed synchronization in such a way that the dog teeth position during shift follows the ideal dog teeth position trajectory. Since the control strategy is based on optimal control theory, its effect on speed synchronization time is minimal. The control strategy is designed in such a way that it can easily be applied in the existing transmission control software. By applying the control strategy on the simulation model, it is shown that the impacts during gear engagement are reduced.
CitationPiracha, M., 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, https://doi.org/10.4271/2019-01-1303.
Data Sets - Support Documents
|[Unnamed Dataset 1]|
- Chen, H. and Tian, G., “Modeling and Analysis of Engaging Process of Automated Mechanical Transmissions,” Multibody System Dynamics 37:345-369, 2016, doi:10.1007/s11044-015-9490-7.
- Duan, C., “Analytical Study of a Dog Clutch in Automatic Transmission Application,” SAE Int. J. Passeng. Cars - Mech. Sys. 7(3):1155-1162, 2014, doi:10.4271/2014-01-1775.
- Hoshino, H., “Analysis on Synchronization Mechanism of Transmission,” in 1999 Transmission and Driveline Systems Symposium, 1999, SAE.
- 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:10.4271/2017-01-2443.
- Math, K.M.H., and Lund, M., “Drag Torque and Synchronization Modelling in a Dual Clutch Transmission,” Master thesis, 2018, Chalmers University of Technology, Gothenburg, Sweden.
- Penta, A., Gaidhani, R., Kumar Sathiaseelan, S., 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:10.4271/2017-01-1596.
- Piracha, M.Z., Grauers, A., and Hellsing, J., “Improving Gear Shift Quality in a PHEV DCT with Integrated PMSM,” CTI Symposium Automotive Transmissions, HEV and EV Drives, 2017, CTI, Berlin, http://publications.lib.chalmers.se/records/fulltext/254760/local_254760.pdf.
- Tseng, C.-Y. and Chih-Hsien, Y., “Advanced Shifting Control of Synchronizer Mechanisms for Clutchless Automatic Manual Transmission in an Electric Vehicle,” Mechanism and Machine Theory 84:37-56, 2015, doi:10.1016/j.mechmachtheory.2014.10.007.
- 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, doi:10.1016/j.ymssp.2011.07.016.