4축 유압 시뮬레이터의 노면형상 구현에 관한 연구

Abstract

In the recent years, as the product liability(PL) act is enforced worldwide, manufacturers must be totally responsible for any defects in the quality of their products. It is important to evaluate the durability and the vibration against this circumstance. The better test for products is to experiment in the actual conditions. However, costs expenses and efforts for the experiment are needed to react the defects of product . This problems can be settled by simulator which supplies the realistic environments. It is especially useful in the test of the products which relate to the safety of human such as vehicles. In this thesis, the 4 axes hydraulic simulator which is generally used in the automobile and the machine industry is designed and manufactured. Also, the driving algorithm and the program are developed to realize the displacement of road profile, and then the performance of the tracking response is measured. The contents are as follows : (1) driving algorithm for driving the hydraulic actuators simultaneously, (2) measurement algorithm for transforming road profile into the displacement and (3) realization algorithm for actualizing road profile by using the hydraulic simulator. Each contents are correlated and details are as follows. First, to ensure the reliability of the hydraulic actuator, the vehicle is excited up to the range of the maximum frequency using the sine wave. The 4 axes hydraulic actuator is developed, and then the correlations between the displacement and servo controller on each axis are examined. The hydraulic actuator is compensated. Second, the measurement algorithm which can obtain the displacement signal is developed to realize the road profile using the 4 axes hydraulic simulator, and the acceptable displacement signal of the road profile in the hydraulic simulator is obtained by the accelerometers. There is the difference between the response signals on the driving file and the expected signals in general vehicles because of the nonlinearity of the suspension, the tire, and etc. Third, the algorithm and program are applied to the 4 axes hydraulic simulator in order to reduce this errors by the repetitive improvement method. Analyzing and ensuring the input and output data through algorithm and program based on PC and window in real time is economically efficient and convenient to use. Moreover, the algorithm in the frequency domain which consists of many DSPs(Digital Signal Processing) is enable to solve the problems which can't solve in the time domain.