Structure‐based dynamic characteristics of planar linkages including platform‐type robots

摘要

A comparative study of kinematic chains and their inversions at the conceptual stage of design is expected to help the designer in selecting the best possible chain and inversion for the specified task. To accomplish this, the designer should be able to read the characteristics of the chains based on their topology. It is only necessary to associate logically certain characteristics, weaknesses, and strengths of a chain to perform a task with the structure of the chain and then generalize. Based on this belief, work has been reported earlier to assess the ability of a chain to reveal some of the characteristics, such as structural error, performance, static, and kinematic behavior. In this study, an effort was made to model a chain as a system of dynamically equivalent lumped masses, interconnected, and then, through energy considerations, show that the distance between ground link and joint masses can be taken as the criterion to compare the chains from the viewpoint of balancing and their expected dynamic behavior. The concepts developed are applied to planar in-parallel robots, which are gaining in importance. © 1997 John Wiley & Sons, Inc.