Study On Intelligent Control Of The Automated Mechanical Transmission For Automobile Based On Driver-road-vehicle System

The automated mechanical transmission (AMT) is a newly developing automatic transmission technology and catches researcher'attention in many countries. The AMT is more efficient and has a lower cost than traditional automatic transmission (AT). The automated mechanical transmission which has a high performance and low price can be manufactured by manual transmission product line with low equipment investment. It is the automatic transmission which fits the reality of development of automobile industry in China and has broad prospects of manufacture and wide applications. Although a good deal of study has been done on AMT there are still many problems due to the characteristic of AMT and complexity of technology. These problems such as automatic adaptive faculty to complicated and volatile environment and different driving intent during start up and shift, system stability and reliability have been studied in depth both in theory and experiment. A driver-vehicle-road closed loop system is constructed. In this system the performance of vehicle influenced by driver, vehicle conditions and environments. Driver is the main input of vehicle and his behavior immediately affect the running characteristic of vehicle; control strategies are varied with environments. According to these requirements recognition methods for drive intent and road condition are analyzed. Data acquisition and processing technique are also discussed. All of these laid the groundwork for intelligent control of driver-vehicle-road system. The control of clutch during start up is one of the most important and difficult point for AMT control. Many factors such as load, road conditions, weather, wear of vehicle and drive intent all affect the control quality of clutch. And meanwhile the vehicle must meet the requirements of ride performance and clutch wear. How to satisfy the two inconsistent targets is the key point of clutch control. The partial steady engine speed control is put forward aim at the defects of present clutch control. High start up performance is guaranteed by coordinating and controlling the engage speed and displacement of clutch and engine rotary speed. Compensatory control strategies are also designed base on the study of relationship between mechanical wear and vehicle parameters. Main modifying factors of shift quality are found out through analyzing the shift quality criterion and shift process. Control measures are brought forward base on smooth and quick shift. The action of clutch during shift is studied and control strategies for clutch engaging and disengaging are designed. Vehicle running conditions are classified according to all kinds of road conditions, drive intentions and running characters. Shift rules which can satisfy all conditions are designed on the basis of the modification of power shift rules and shift rules for some special conditions are also simulated. the concept of intelligent integrate shift system is set up and gear decision method under complex coupling conditions is put forward. Shift, start up and ride performance will be improved and clutch life will be prolonged if engine speed is well controlled according to control strategy and car dynamics. Electric throttle is used in AMT system. Engine speed can be well controlled during start up and shift by controlling electric throttle opening. Development of AMT system is carried out. Actuator of automatic electric clutch and shift are also developed. This kind of Actuator is simple in construction, low in cost and reliable in working. Its performance achieves the anticipated result. DSP control unit of AMT is developed; test bench of AMT system is built up and test cars of AMT is also developed. Testing under different work conditions has been done both on bench and cars. The results indicate that this AMT and its control system have a good performance. The driver-vehicle-road intelligent control theory is verified in practice.