Conference article

The presented work is currently focusing on the dynamic analysis of a worm gear drive mechanical system by multibody contact simulation of a force constraint problem and efficiency analysis. Such systems can be modelled by a Two-Sided Wedge Mechanism (TSWM )as Translational Designed Dynamical Model where worm gearmesh friction contact is exhibited on a plane by two slope active contact lines between conjugated wedge-like rigid inertial bodies via the presence of backlash. This model has been developed to simplify visualization of internal contact conditions and force/reactions distributions resembling a screw-like worm gear mesh. The different dynamical regimes of motion (called as “tractive” and “inversetractive”) are resulted with respect to the type of a Force Transfer Function between reduced dynamic reactions and appropriate force constraints. The transition from one regime to another physically means instantaneous lose and re-establishing contact line due to the backlash which is resulted in discontinuous event at the force contour/flow level. The mathematical problem formulations have been resulted in the residual ODE form with unpredictable discontinuities in the right-hand side within the set of the Force Transfer Functions. An additional Switching function for control and numerical realization of motion in different regimes has been included. The problem has been tested by MATLAB ODE solver with added switching conditions that incorporated into continuous ODE system. The reduced model parameters of a real-life Motor Operated Valve with the worm gearbox are used in the numerical simulation.

Multibody contact systems; internal force contour; friction; force transfer function; switching function and logic; discontinuities

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