Aiming at estimating the road surface condition with improvement of the accuracy in spatial, this paper proposes a new method to classify road surface condition by considering identification interval based on vehicle system responses. First, the response signals in different vehicle speeds are decomposed by using both Wavelet Transform (WT) and Empirical Mode Decomposition (EMD) techniques. Then characteristics of the signals in both the time and decomposed frequency domain are subsequently extracted. An Improved Distance Evaluation Technique (IDET) is used to select superior features from the characteristics. Finally, a Support Vector Machine (SVM) classifier is applied to determine the road classification. The influences of identification intervals in spatial accuracy are discussed, and an adaptive classification interval was proposed to improve accuracy. The algorithm is validated by using both simulation and experimental results.

Abstract. Upper-equipment mounting system is playing more and more important role in the field of transportation vibration isolation. This study summarizes configuration categories, development and research status of the mounting system. Research direction future need of the mounting system is also proposed.

Applying the multi-dynamic theory, a dynamic model of the upper-equipment mounting system of some vehicle is established. An optimization model for the upper-equipment mounting system is constructed, in which the driver's vertical acceleration RMS value and upper equipment vertical acceleration, pitch angle acceleration and roll angle acceleration of the RMS value are selected as objective function, and the mounted stiffness and damping as design variables of optimization.