Nonlinear dynamic interactions between a cable with no axial preload and its casing - Application to automotive gearshift command systems

摘要

A gearshift command system is composed of a cable encapsulated in a casing. The cable transfers the motion of the gearshift lever to the gearbox selector lever. The work presented focuses on the cable-casing system and its non linear behavior. A first step of the analysis consists in calculating the cable-casing path starting from the boundary conditions given by the positions and slopes at the extremities and the passing points. A non linear co-rotational finite element formulation is used in order to model correctly the large displacements involved. The cable-casing contact problem is solved using the penalty method. Contact points between the cable and the casing are computed. The stiffness matrix computed from the spatially curved cable-casing within the contact points is then the starting point for the second part of the analysis. It concerns the dynamic behavior simulation of the cable-casing under harmonic excitations. The computation uses the Newmark time integration scheme and the dynamic time responses are calculated around static equilibrium positions previously determined. Comparisons between simulation and experiment are presented.