抄録
The usual way of shock absorber description in the framework of multibody system dynamics is the usage of force-velocity characteristics that allow to describe the damper force with respect to the relative velocity of damper compression and extension. The disadvantage of this approach to the damper description consists in the lack of force dependency on changing velocity conditions because the characteristic is usually measured for the given harmonic kinematic excitation. The method presented in this paper is characterized by extended measurement based on a hydraulic actuator, which can be used for a wider set of excitation signals. Moreover the relative motion acceleration is evaluated as the second independent variable and thus the obtained damper force can be viewed as a function of two variables (velocity and acceleration) -- it is so called global damper characteristic. Particular damper characteristic measurements are described in the paper together with data processing and possible model identification. Then the characteristics are used in a quarter car model in order to develop the methodology of the global characteristics modelling implementation and force calculation. The quarter car model is created using the real data and parameters of the SKODA 21 Tr trolleybus. The introduced shock absorber modelling methodology brings a more accurate damper description mainly for the simulations with changing loading conditions in the form of varying excitation or changing vehicle speed.
