Control Theory And Test On TC And AMT System Of Off-road Vehicle

After considering the passive and flexible features that the Off-road vehicle has, and the high transfer efficient and easy making and low cost that Automated Mechanical Transmission (AMT) has, and the adapting to out-load and lowing vibration and enlarging out-torque the Torque Converter (TC) has widely, the TC work with AMT is adapted in the NJ2046 Off-road vehicle. In order to improve the general performance of the Off-road vehicle equipped with TC+AMT and combing the detail requirements of the state key project—"Study of Torque Converter and Automated Mechanical Transmission of Off-road vehicle", the hydraulic transmission is used in low shifts (1 ,2 shift) and the high efficient lock-up control are applied in high shifts (3,4,5 shift) for the high fuel economic and spread the work field in the better road. Some new ideas and useful technical methods are put forward and parts of them also are applied in the NJ2046 Off-road vehicle during the research of the automatic transmission.1．Firstly the research procedure of the automobile automatic transmission development is analyzed comprehensively, especially the important performance of the TC+AMT automatic transmission, which realize the functions of the Off-road, and passive and flexible and so on during military moving and fighting that the Off-road vehicle must have, is emphasized. The features and structures and types of the TC+AMT with lock-up and slip of the Off-road vehicle are introduced, the hydraulic control system and method to realize the comprehensive control and the applied control theory and technique in different fields are put forward too, meanwhile the destination and significance are introduced, the main research works that consider Off-road vehicle feature is determined.2．The start and shift procedure of the Off-road vehicle with AMT are analyzed in theory, especially the main factors including engine output characteristics and throttle changing gradient and clutch connecting speed, which effect automobile starting and shifting quality, are described in detail. In order to improve shift quality, the control schedule that takes the driving comfortable as the key performance and the shock degree as the restrain factor is established. Meanwhile in order to test and verify the effect of all parameters efficiency and reasonability to the driving comfort, the tests have been done according to the compiled software to sample data and control system, when the NJ2046 sample Off-road vehicle are in empty load or full load that the vehicle moves in the deferent road conditions and in deferent throttle opening gradient starting and in deferent clutch connecting speed, the tested results are analyzed, taking the dynamic three parameter(throttle, vehicle speed, accelerator gradient) as the control theory, the shift procedure control schedule that meets driving comfort is established. The test verified that the designed control schedule of start and shift is correct.3．According to the engine character and hydraulic torque converter original character and the reasonable match principle, the engine working with torque converter together dot is been found. On the basis of the power train dynamics model, the work together input character between TC and engine is defined, the best shift dot is fixed under the principle of meet the dynamic attraction in low shifts (including 1,2) and economics in high shift (including 3,4,5), the shift schedule of the TC works with AMT and the comprehensive shift schedule of TC with lock-up work with AMT are formulated, those schedules are compared with the shift schedule of the AMT too. Because the TC adopt the outside resistance and the rotate changing, it can low the shock degree and absorb the vibration of the shift procedure and improve driving convince. Meanwhile it can absorb the engine shock and vibration that the road condition changes during the Off-road vehicle moves normally. It also reduce driver fatigue and improve shift quality and prolong the lifetime of the vehicle parts, so the smooth pe...