ABSTRACT
Design of circularly symmetric compliant elements is not new. Established markets already exist that provide various springs and elastic couplings that may be readily used for applications where transmission of linear translations or rotations are desired. This chapter draws from the wealth of information already developed for such mechanisms. In many cases it is desired that a flexible coupling be provided between two rigid bodies having rotational symmetry. In fact, for most motor driven shaft assemblies, a flexible coupling is necessary to accommodate the small misalignments inevitable in any assembly. In addition to misalignments, the ends of the shafts may also require some relative motion. Probably the most familiar couplings are the universal (or Hooke) joints and constant velocity couplings used to transmit rotary motion from engines to the driven wheels on automobiles. Although less familiar, there is a not-lesscommon requirement for couplings to connect between many types of machines such as electric motors to gearboxes and, subsequently, gearboxes to machinery.
