Dynamic modeling of high precision servo systems with gear backlash

Yumrukçal, Zafer
Although the mechanical solutions, like spring preloaded hinge mechanism, compensate for backlash in servo drive systems with high precision positioning requirement, these solutions may not be preferred because of their drawbacks like high friction forces/torques and diminished life cycles for mating gears. Besides, the use regular gear meshes could be enforced by any reason, like cost efficiency or simplicity of the solution. On such occasions, to maintain performance requirements like high positioning accuracy, alternative control methods can be used with regular gear meshes. For the purpose of developing a controller, it is important to develop a model for the physical system. This thesis work aims to fulfill the requirement for a dynamic model of a servo system with gear backlash which is to be used as a base for the development of a controller. In the scope of this thesis work, firstly, a literature survey has been conducted to examine the approaches for identifying and modeling a dynamic system with gear backlash. Following the literature survey, a real servo system with gear backlash has been identified and a dynamic model of the system has been developed. Simulation results from the system model compared with the test results obtained from physical system and validity of servo system model with varying backlash limits has been presented.


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Citation Formats
Z. Yumrukçal, “Dynamic modeling of high precision servo systems with gear backlash,” M.S. - Master of Science, Middle East Technical University, 2013.