Practical Damper Velocity Estimation for Semi-Active Suspension Control

Semi-active suspensions have much better performance than the passive suspensions along with the advantages such as low power consumption and cost. In order to control the semi-active suspension system, such as MR damper, sensory feedback is required. The skyhook control which is the most widely used algorithm admits the velocity of damper and vertical sprung mass. For this, additional attachment, such as a displacement sensor (e.g., an LVDT) or an accelerometer at the sprung mass is required. The present study proposes a method for estimating the damper speed from a pre-existing IMU sensor and a lower damper accelerometer considering the damper orientation in practice. It was validated that the performance of the skyhook-controlled suspension matches with the proposed algorithm.