3D compliant mechanisms synthesis by a finite element addition procedure

This work presents an element addition strategy for 3D compliant mechanisms design. The proposed procedure is based on an extension of the evolutionary structural optimization (ESO) method, which has been successfully applied to several optimum material distribution problems, but not for 3D compliant mechanisms optimization.Even if most investigations for compliant mechanism design have been oriented for planar systems design, this technology may be useful also for 3D mechanisms design, for instance in making devices for micro- and nanomanipulation, like the popular hexapods mechanisms used for six axis positioning. These 3D structures and mechanisms (rigid or compliant) must be carefully manufactured and assembled from many precision components, and there are still many aspects that must be examined to accomplish the topology optimization and ensure the performance of these precision manipulators. The present paper aims to progress on this line, and will apply an alternative approach derived in this investigation, which improves the solutions obtained by this specific method. The proposed method has been tested in several numerical applications and benchmark examples to illustrate and validate the approach, and satisfactorily applied to the solution of 3D examples.