Gear change selection and clutch control of an automated manual transmission vehicle

Abstract

The aim of this report is to provide a detailed overview of Automated Manual Transmissions (AMT) from its control point of view. An introduction about AMT is given, stating its main advantages in terms of cost and efficiency compared to other transmission types and justifying the context which makes AMT an interesting system for investigation. It is stated as well its importance for the Ford Focus prototype vehicle, where the project will carry the investigation. This leads to the aim and objectives. Then, previous research about AMT is summarized. Starting with the common problems of AMT, some proposed control strategies follow, which aim to solve the discussed problems. As well, AMTs actuator control strategies are presented. All this analysis led to some recommendations which guide the next steps of the project. Continuing with, the vehicle is introduced with major emphasis on the AMT system. It is explained the present components and new drivers that are designed and built, which provide the functionality needed for the AMT. Next, the controller architecture development process is discussed. Starting from the low-level controllers for each of the AMT actuators, it is explained the strategy used to achieve the control of them. It includes an interesting discussion on how to use the sensors present on the actuators to achieve position control without position feedback. Then, it follows the details on how each actuator is integrated in high-level controllers until achieving the complete control of the AMT successfully. Finally, some conclusions are drawn stating the importance of the feedback sensors for gearbox controllers and the clutch control concerns. Guidance is as well given for further investigation on the AMT system of the prototype vehicle. Keywords: Gearshift, Gearbox Actuators, Gearbox Control, Clutch Control, Shift Shock, Shift Time, Vehicle Start, Simulink, Stateflow, Synchromesh, dSpace.