Coupling vibration characteristics of a translating flexible robot manipulator with harmonic driving motions

摘要

Translating robot manipulators (TRMs) especially flexible translating robot manipulators (FTRMs) have been actively used in takeout robots, beam-type substrate transport robots and manufacturing machines and it remains that the end-effector on robot arms should have a good operating accuracy. Due to the coupling effect, such as motor parameters and mechanism inertias, the motions of the driving stage exhibits certain disturbances especially in high speeds. Considering the influence of the motion disturbances, this paper models the motions of the driving stage as harmonic driving motions and in this case the FTRM is similar to a parametrically excited system. The multiple scales method is applied to obtain the stability conditions for the motion disturbances. Based on the established coupling dynamic model, the influences of the motion disturbances on the vibration behaviors and the stability are investigated. Moreover, considering the actual motion characteristics of the driving stage with varied accelerations and velocities, the effect mechanism between the motion characteristics and motion disturbances are subsequently studied. According to this effect mechanism, the influence of the motion disturbances can be suppressed through motion optimizing, which is meaningful for motion optimizations and vibration controls of the FTRM. An ADAMS physical prototype is constructed to verify the dynamic model and theoretical analysis results, and the results have a good agreement.