Error Analysis of a Stewart Platform Based Manipulators
نویسندگان
چکیده
Hexapod characteristic analyzed in this paper is the effect of small errors within its elements (strut lengths, joint placement) which can be caused by manufacturing tolerances or setting up errors or other even unknown sources to end effector. If all error values are known or can be calculated then they can be included in a model which will eliminate their defective effect. In practice there are very few error elements that are known in advance. For all others their values can just be assumed. What can be done now is to find a way to approximate value for maximal end effector displacement. The method we propose is a numerical method which is based on differential equations of close loop vector chains. The method can be used to calculate maximal end effector error for specific position and also for validation of entire hexapod workspace area, as shown in this paper.
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