Beam Bending and Spring Stresses

To illustrate how traditional materials such as metals limit the design process, consider a spring. The manufacturing process in metals limits the options available in producing a variety of shapes in this material. As a result, steel springs are produced in basically only three shapes the torsion bar, the helical coil, and the flat-shaped leaf spring. By comparison, TPs and TSs can be easily fabricated into 

As an example plastic replaced a metal pump in a PVC plastic bag containing blood. The plastic spring hand-operating pump did not contaminate the blood. 

A zigzag configuration may be seen as a number of separate beams each with one end fixed. The top beam is loaded (F) either along its entire length or at a fixed point. This load gives rise to deflection y at its free end and moment Mat the fixed end. The second beam is then loaded by moment M (upward) and load F(the effective portion of load F, as determined by the various angles) at its free end. This moment results in deflection yi at the free end and moment Mi at the fixed end (that is, the free end of the next beam). The 

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