Modelling and ride dynamics of a flexible multi-body model of an urban bus

Abstract

Dynamic response of a large order mechanical model of an urban bus is investigated in this paper. The emphasis is first put on developing a quite complete model, which can be utilized in order to extract sufficiently reliable and accurate information related to its dynamics in a fast way. Since some of the components of the bus undergo large rigid body rotation, in addition to motion resulting from their deformability, a multi-body dynamics framework is adopted. This implies that the resulting equations of motion appear in the form of a strongly non-linear set of differential-algebraic equations, which are difficult to handle even numerically. In fact, the modelling becomes more involved because all the significant non-linearities appearing in the interconnections of the structural components and especially in the front and rear suspension subsystems of the bus are taken into account. In order to alleviate some of these complexities, the number of degrees of freedom of each component, associated with its deformability, is reduced drastically by applying an appropriate coordinate condensation methodology. Finally, this model is employed and numerical results are obtained for motions resulting from typical road excitation. In particular, selected response quantities related to ride comfort are examined for characteristic combinations of the bus suspension stiffness and damping parameters.

Forecasting the durability of public transport bus bodies depending on operating conditions

“…Based on the procedure reported in [11], a mathematical model was built, which describes the transfer of effort from the micro profile of a road to the examined element of the body frame [13]. The model given in [13] takes into consideration, similarly to the model reported in [14], the forces transmitted from the road micro profile but the model from [13] also takes into consideration the corrosion of the bus body frame, which corresponds to actual operating conditions. The corrosion processes of the bus body are described in [15], considering [16], and according to dependences [8], derived from treating the statistics on bus operation in cities with different numbers of inhabitants.…”

Survey of the Application Fields and Modeling Methods of Automotive Vehicle Dynamics Models

“…The purpose of the vertical dynamic models is to investigate the motion, vibrations of the vehicles in the vertical direction [47], [48]. By using these models, the suspension behaviour, comfort of the vehicle can be analysed as well as the design and fatigue analysis of the suspension components can be performed [49].…”

Személygépjárművek dinamikai modellezési eljárásainak áttekintése

“…A vertikális járműmodellek céljá á járművek függőleges irányú mozgásánák vizsgálátá [9], [10]. Ezen modellek segítségével á jármű rűgózási tűlájdonságái, komfortjá elemezhető, méretezhetők á fűtóművének álkátrészei, stb.…”