Periodic and chaotic dynamics of motor-driven gear-pair systems with backlash

Dynamics of gear-pair systems driven by motors and presenting speed-depende nt moment resistance is investigated. First, a suitable mechanical model is developed, taking into account the gear mesh backlash and static transmiss ion error as well as the essential nonlinearities due to the bearing cleara nce and contact characteristics. In comparison with earlier related studies , the new element of the present work is that the model developed determine s the system response by simply specifying the external loads, rather than by assuming an a priori value for the constant mean angular velocity of the gear shafts. In fact, models employed in earlier research studies are show n to be obtained as special cases of the present model. The study is comple ted by numerical results. First, classical response diagrams are presented, illustrating the effect of the most important parameters on the system res ponse. Finally, direct integration of the equations of motion is also perfo rmed, demonstrating the existence of quasi-periodic and chaotic long time r esponse for selected combinations of the system parameters. (C) 2001 Elsevi er Science Ltd. All rights reserved.