The use of layer-by-layer deposition and selective processing promotes geometrical flexibility so a certain extent. In operational mechanisms, two or more components must move with respect to one another: AM can build these components fully assembled. For instance, a five-fingered robotic hand prototype featuring fingers with four degree of freedom was fabricated by Selective Laser Sintering . One of the key parameters for performance is the joint clearance .
Some AM methods also facilitate the ability to embed functional parts such as electric motors, gears, silicon wafers, printed circuit boards, and strip sensors.
Multiple materials can be used concurrently in AM to increase components functionality such as with ultrasonic additive manufacturing or with functionally graded materials (FGM) [6–9] made by direct laser deposition.
Functionally graded rapid prototyping (FGRP) is a novel design approach and technological framework enabling the controlled spatial variation of material properties through continuous gradients in functional components [10-14].
For instance, design can combine structural, environmental, and corporeal performance by adapting elements such as thickness, cell density, stiffness, flexibility, and translucency to load, curvature,…
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