A FRAMEWORK ESTABLISHING THE BOUNDS OF SMALL ANGLE ASSUMPTIONS IN MULTI-MATERIAL ADDITIVELY MANUFACTURED COMPLIANT MECHANISMS

Additively-manufactured multi-material compliant mechanisms are an emergent class of mechanisms; these mechanisms have a higher reliance on material properties to drive deflection when compared to other compliant mechanisms. As a result, material-specific properties such as Young's modulus, strain response, and Poisson's ratio must be analyzed to properly predict the performance of multi-material additively manufactured compliant mechanisms. This paper creates a framework for additive manufacturing users to characterize acceptable force-deflection relationship predictors using strain data associated with a generalized multi-material cantilever beam. This allows designers to have more confidence in the performance of their designs prior to production. When applied, the framework allows the user to identify the applied deflections where Hooke's Law and small angle assumptions are, or are not, appropriate. This process will be useful for multi-material additive manufacturing processes capable of producing multi-material prints: directed energy deposition (metals) and material extrusion (thermoplastics). This process will serve as the basis for encouraging the widespread adoption of additively manufactured multi-material compliant mechanisms.