Centers of Action, Symmetry, and Reciprocity
Centers of Action are virtual points on a body that describe the center of a physical parameter. This encompasses center of mass, the center of stiffness, the center of gravity and more. All the centers of action should be taken into consideration when designing the overall system.
Symmetry is a design tool that can be used to minimize errors as well as a potentially detrimental problem like with symmetrical expansion of an object causing misalignment.
The concept of reciprocity comes from Maxwell's Principle of an equal and opposite response force. From a design thinking perspective, reciprocity is considering reversals and critical thinking outside the typically expected solution.
For our project, we build a double parallelogram flexure that minimizes parasitic errors that would be seen in a single 4 bar flexure
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