  We synthesize monolithic topologies of constant output (CoFM) and input
(CiFM) force mechanisms. During synthesis, we capture all possible aspects of
member deformation including finite displacements, buckling, interaction
between members, their interaction with external surfaces, and importantly,
interaction of the mechanism with flexible workpieces to capture force transfer
in true sense. Features of constant force characteristics, e.g., magnitude(s)
of the desired force(s), range of input displacement over which slope of the
force displacement curve is near zero, and distance between workpiece and the
mechanism are controlled individually via novel objectives proposed herein. Two
of the constant output and constant input force mechanisms each, are
synthesized using stochastic optimization ensuring ready manufacturability. We
observe that presence of external surfaces may not be required for singlepiece
mechanisms to attain constant force characteristics. However, interesting
solutions are possible if mutual contact is permitted. We also note that
desired force characteristics may not remain the same with alteration in the
workpieces shape and (or) material properties. We finally fabricate and test
the synthesized mechanisms and find that the desired constant force
characteristics are by and large retained.
