Abstract:

The quasi-zero-stiffness is obtained by connecting in parallel elements with positive and negative stiffness, in which the negative stiffness is obtained by a pair of linear springs placed horizontally. An appropriate second suspension system is designed by combining the quasi-zero-stiffness with the U type side frame of the tramcar. The stiffness characteristics and transfer rate of the second suspension system are gained respectively by static and dynamic analysis. A low-floor tramcar model with three cars is established by SIMPACK, which was co-simulated with MATLAB/SIMULINK. The results shows that compared with the equivalent linear suspension, the quasi-zero-stiffness suspension is of extent isolation frequency and better vibration isolation characteristics especially in the low frequency range. The low-floor tramcar with second quasi-zero-stiffness suspension is of lower vibration in car body, better running stability and ride comfort.

Key words: co-simulation, quasi-zero-stiffness, rail quality, Transfer rate, low-floor tramcar