Abstract: A real-time estimation algorithm of lateral speed for center of the vehicle mass, which is called composite method, and used for vehicle stability control (VSC) system, is introduced. The algorithm makes full use of advantages of direct integration method of the lateral speed modeling estimation method. Based on the composite estimation model, the equations of continuity state are dispersed, and the calculation of feedback matrix for closed loop observer and coefficient matrix of discrete model are presented. The test results show that the composite method draws the advantages of both the direct integration method(the insensitivity) and lateral speed modeling estimation method(non-accumulated errors). The composite method can successfully avoid disadvantages of both the direct integration method and the modeling estimation method, and show the better performance.

Key words: Closed loop state observer, Lateral speed for center of the vehicle mass, Real-time estimation algorithm, Vehicle stability control