[동력전달계부문] 승용차용 자동변속기의 HILS

Recently, most passenger cars that are equipped with automatic transmission prevail in domestic market because of convenient and comfortable driveability though there are some demerits in cost and fuel consumption compared to manual transmission. The major interests of car manufacturers in development of automatic transmission are durability and shift quality. However, a large number of researehes for improving shift quality that are based on dynamic characteristics of shifting mechanism are not adopted in the developing process so far because it is quite difficult to predict the shifting performance from the dynamics simulation. One of the important reasons for the difference between simulation results and experiments arises from the automatic transmission hydraulic system that consists of many valves with high order and shows a lot different dynamics to temperature variation. In this work, Hardware-In-The-Loop simulation system for automatic transmission is developed for improving the accuracy of simulated result by interfacing the real-time simulation model with the real hydraulic system. The real-time simulation for automatic transmission model excluding hydraulic system is executed with TIs TMS320C31 DSP and the additional 16bit micro-controller system is designed for acquiring the simulation data and auxiliary interfacing. We verify the proper operation and correctness of shifting result by comparing the off-line simulation result with that of HILS. We are planned to implement the whole HILS which includes transmission dynamometer driven by electric motor and test the performance of HILS in the near future.