摘要：In mechanisms design, one of the more common tasks in kinematic synthesis is
motion generation (rigid-body guidance), where a rigid body is moved through
a specified motion. If the body to be guided is flexible and has an initial
smooth shape, the task of moving it from its initial configuration to a
specified, also smooth, configuration, is referred to as segment-motion
generation. This is the case for compliant four-bar mechanisms, where the
flexible coupler link is the body to be guided, and the (also flexible) input
and follower links are the ones to be synthesized. Previous works on this type
of compliant mechanism neglected the shear stress induced in the links, and
the used technique disjoined the mechanism in order to synthesize a
single-link at a time, that would accomplish the specified task. In
this paper we conceive a more realistic approach, considering all flexible
links as two dimensional beams with shear deformation, and synthesized the
input and follower links simultaneously, as the flexible guided body is moved
through a sequence of discrete prescribed “precision shapes” in addition to
rigid-body motion, in order to achieve its specified task. The synthesis
problem is solved by optimization of the finite element model, and the method
is tested with a numerical example.
