Multi-criteria optimization of a hexapod machine. (English) Zbl 1161.74461

Ambrósio, Jorge A., Advances in computational multibody systems. Revised and enlarged versions of selected communications presented at the ECCOMAS thematic conference in multibody dynamics 2003, Lisbon, Portugal, July 1–4, 2003. Dordrecht: Springer (ISBN 1-4020-3392-3/hbk). Computational Methods in Applied Sciences (Springer) 2, 319-343 (2005).
Summary: Alternative designs of a hexapod machine are proposed and investigated with the aims to reduce flexibility and to eliminate singular kinematic configurations that appear in the workspace for the current design of the machine. The hexapod is modeled as a rigid multibody system. Articular coordinates associated with desired tool trajectories are computed by inverse kinematics. Hence, dynamic forces and torques are not considered and, as there is no closed-loop control realized in the model, the actual rotational and translational position of the tool deviates from the desired position due to machining loads. These deviations serve as objective functions during a multi-criteria optimization in order to determine the best design regarding stiffness/flexibility of the machine. Further, a general approach for evaluating flexibility behavior of the machine in the complete workspace is introduced and the results from the optimization are verified. Besides flexibility, a crucial point for machining tools is the size of the feasible workspace. Therefore, the influence of the design modification on the workspace is also taken into account.
For the entire collection see [Zbl 1085.70003].


74P10 Optimization of other properties in solid mechanics
74K99 Thin bodies, structures
70E60 Robot dynamics and control of rigid bodies