Shift characteristics analysis and smooth shift for an automatic power transmission
- 322 Downloads
Smooth shift is one of the key issues in automatic power transmission control systems. However, the torque sensors are too expensive to be used in shift controllers on production vehicles. In order to provide a basic strategy for smooth shifting by using RPM sensors only and in order to accomplish the shift within a designated time, this paper studies detailed characteristics of the smooth shift for clutch-to-clutch shift mechanism. A desired trajectory of slip speed is proposed for smooth acceleration shift defined in this paper. Also the clutch torque needed to achieve this trajectory is derived, and it may be used as a open loop shift control law.
Key WordsClutch-to-Clutch Shift Smooth Shift Engaged Clutch Torque Indirect Acceleration Shift Heat Dissipation Dynamic Shift Condition
Unable to display preview. Download preview PDF.
- Cho D., and Hedrick J. K., 1989b, “Sliding Mode Control for Automotive Powertrains with Uncertain Actuator Models,”Proceedings of the 1989 American Control Conference, Pittsburg, PA.Google Scholar
- Jeong H. S., 1993, “A Study on the Shift Control of a Vehicle Power Transmission System,” Ph. D. Thesis, Dept. of Mechanical Design and Production Engineering, Seoul National University.Google Scholar
- Jeong H. S., and Lee K. I., 1994a, “A Study on the Design of an Indirect Shift Transient Torque Controller for an Automatic Power Transmission System,”Journal of Korea Society of Automotive Engineers, Vol. 2.Google Scholar
- Jeong H. S., and Lee K. I., 1994b, “Shift Transient Torque Control of a Vehicle Power Transmission System,”FISITA’94 Congress, pp. 265–271.Google Scholar
- Jeong H. S., and Lee K. I., 1998, “Efficient Simulation Methods for Automatic Transmission Applying Dynamic Torque Constraints,”Journal of Korea Society of Mechanical Engineers, Vol. 22, No. 3, pp. 504–518.Google Scholar
- Jeong H. S., and Lee K. I., 1999, “Friction Coefficient and Torque Estimation and Smooth Shift Control Law for an Automatic Power Transmission,”submitted for International Journal of Korea Society of Automotive Engineers.Google Scholar
- Kotwicki, A. J., 1982, “Dynamic Models for Torque Converter Equipped Vehicles,”SAE Paper No. 82039.Google Scholar