Application of magneto-rheological dampers for heavy truck suspensions

摘要

This study evaluates the performance of a semiactive magneto-rheological primary suspension on a heavy truck application. A set of controllable magneto-rheological dampers are fabricated and used to test the effectiveness of semiactive suspensions on a heavy truck. An embedded controller is used to determine the damping level according to the skyhook control scheme. Eleven accelerometers are used to measure the acceleration at various points on the truck. The measurement positions include fourmeasurements on the axles of the truck, four measurements on the frame of the truck, and three measures at the B-post.The performance of the truck equipped with the semiactive magneto-rheological suspension is primarily compared to the performance of the truck with the original (stock) passive dampers. Results from operation with the adjustable dampers fixed in boththeir on and off states are also given. The performance of the semiactive and the original passive dampers are compared for two different driving situations. First a test case where the truck is driven over a speed bump at approximately 8-11 Km/h (5-7mph). The second comparison is for a test case where the truck is driven at a constant speed along a stretch of straight and level highway at a constant speed of 100 Km/h (62 mph). Acceleration data for both of test cases is analyzed in both the timedomain, and in tae frequency domain.The data for driving the truck over speed bumps indicate that the magneto-rheological dampers used in this study with the skyhook control policy have a small effect on the vehicle body and wheel dynamics, as compared to the passive stock dampers. Thehighway data shows that magneto-rheological dampers and skyhook control policy are effective in reducing the root mean square (RMS) of the measured acceleration at most measurement points, as compared to the stock dampers.