In this paper the effect of leg inertia on hexapod dynamics is investigated. Hexapods under investigation are a new type that is made of sliding legs with constant lengths. A complete dynamic model of sliding-leg hexapods is developed including leg inertia. Based on this dynamic model, the effect of leg inertia on hexapod dynamics is investigated in terms of two parameters. The first parameter is the ratio of the total leg mass to the mass of the moving platform, and the second parameter is the acceleration of the moving platform. Numerical studies reveal that the effect of leg inertia may be negligible at low speeds, but becomes significant at high speeds. Hence, leg inertia must be included for modeling hexapod dynamics for high-speed applications.

Issue Section:
Technical Papers
Keywords:
manipulator dynamics, manipulator kinematics, machine tools
Topics:
Dynamics (Mechanics), Equations of motion, Inertia (Mechanics), Modeling, Machine tools, Dynamic modeling
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Copyright © 2001
 by ASME
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