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The shifting process always activates some changes of noise quality for its transient characteristics, especially for non-powered-shift transmissions, with which the power from engine is intermitted during the shifting period, such as Manual Transmission (MT) and Automated Manual Transmission (AMT). This type of noise change should have a very close relationship with the status of engine directly. But the essential reasons and how to estimate the noise have not been explored before. Therefore there is no clear understanding upon it and no formal methods yet described in the literature. The present study focuses on the phenomenon and makes effort to build reasonable research methods based on vehicles equipped with AMT. Furthermore, the metrics for assessing the noise has been developed with several different experiments and Support Vector Machines (SVMs) technique.

The general way to generate shifting schedule for a new developed vehicle is taking manual calibration way and doing test on the real vehicle that means a time-costing duty. Shift schedule auto-generation has been taken by more and more manufactures for its high efficiency. For auto-generation way, two groups of data set are important. The first is engine steady test data; and the other is drivability constraints defined by customers. Some useful results have been achieved in the field of passenger cars. But for off-road vehicle, there are some special requirements needed to consider, such as vehicle mass, 4WD function and etc. Four-wheel drive vehicles ask for more attraction for improving their performance considering their working in various driving environment. Automatic Transmission has been widely equipped in demanding off-road vehicles responding to the complex driving requirements for its advantage of easy operating.

The paper details an analytical redundancy fault diagnosis method of automated mechanical transmission (AMT) control system. The basic principle of AMT is depicted. After concisely introducing the models of engine, gear box and clutch, which are used to provide redundant information, the diagnostic logic is illustrated in detail. The information redundancy in the local models of the powertrain and the structure logic relations among the assemblages is used to detect and diagnose the faults of the sensors, the actuators and the unit assemblages of the AMT system. The fault codes and fault process measures are listed out.

The coordination of engine will influence the starting and shifting quality of AMT. Heretofore, the study on this aspect is mainly limited to the engine torque control. But for the difficulty of installing torque sensor, just open loop control is adopted, so that the effects don't be satisfactory. This paper puts forward the strategy of engine constant speed control in starting and shifting process, based on the view of kinematics and dynamics. The main idea is that the target speed of engine is constituted according to the different throttle opening, and the deviation between the target speed and the actual speed will be limited through clutch control and fuel injection control in starting and shifting process, which not only greatly reduce the work of slipping and prolong the life of the clutch, but also reduce the fuel consumption and the noise, improve the shift quality in starting and shifting process.

To reach the goal of optimal performance match between engine and transmission, the dynamic characteristics of engine should be taken into consideration. In the paper, the dynamic torque and fuel consumption models of engine, described by a multi-layers feed forward neural network, were established. Based on that, the methods used to calculate the optimal dynamic and economical shift schedules with dynamic 3-parameters were put forward. The shift schedule with dynamic 3-parameters based on neural network model is proven to be superior to the shift schedule with only 2-parameters in both dynamic performance and fuel economy by the test.

The paper introduces an on-board fault diagnosis strategy based on analytical redundancy suit for automated mechanical transmission (AMT). Through experiment and theory analysis an identified engine model, a gear box model and a dry clutch model controlled by hydraulic actuators are respectively established. The information redundancy in the local models of the power train and the structure logic relations among the assemblages is used to detect and diagnose the fault in the sensors, the actuators and the unit assemblages of the AMT system. The method has been used in the AMT control system developed for the SVWSANTANA2000.

Starting control takes an important role in the system of Automated Mechanical Transmission (AMT); clutch engagement control is the key of it. For the purpose to improving the starting performance of AMT, this paper develops the relation between clutch engaging speed and starting jerk, the relation between engine rotate speed and the friction work in starting process. According to the relations, a starting control strategy of keeping the engine rotate speed constant is putted forward in this paper. The main idea of the strategy is to keep the engine run at a lower rotating speed and don't make it flameout through controlling clutch engagement distance and clutch engagement speed in starting process. Based on the strategy, the clutch control map figures which individually correspond with throttle opening, engine rotate speed and difference between clutch master and slave plate rotate speed are built.