The evolution of prosthetic limbs continues to develop, with novel manufacturing techniques being evaluated, including additive manufacturing. Additive manufacturing (AM), or 3D-printing, holds promise for enabling personalized and tailored medical device options. The requirements for personalized medicine, coupled with the limitations of small-batch manufacturing, have made the technique viable for exploration. In this manuscript, an approach is presented for incorporating additive manufacturing for prostheses, both as a final part and in applications as an intermediate manufacturing step. As a result, through the use of these methods a multi-gesture capable electromyographic prosthesis was designed and manufactured, currently being evaluated in clinical trials for pediatric patients. This paper explored the results of this unique method of applying additive manufacturing techniques, and assessed how the blend of different manufacturing techniques improved performance and reduced device weight. Creating unique and aesthetic cosmetic coverings for the device was achieved through using additive manufacturing as an intermediate manufacturing component and, then, applying thermoforming. Cosmesis components saw a 33% reduction in weight from this change in manufacturing. The approach is explored to blend multiple manufacturing techniques to create cosmesis components and structural components for the prosthesis. The techniques serve the design intent to reduce reported challenges with upper limb prosthesis devices and to encourage device retention. Recommendations for manufacturing strategies are discussed, including the limitations.

Adapting grasp-specialized biomechanical structures into current research with 3D-printed prostheses may improve robotic dexterity in grasping a wider variety of objects. Claw variations across various bird species lend biomechanical advantages for grasping motions related to perching, climbing, and hunting. Designs inspired by bird claws provide improvements beyond a human-inspired structure for specific grasping applications to offer a solution for mitigating a cause of the high rejection rate for upper-limb prostheses. This research focuses on the design and manufacturing of two robotic test devices with different toe arrangements. The first, anisodactyl (three toes at the front, one at the back), is commonly found in birds of prey such as falcons and hawks. The second, zygodactyl (two toes at the front, two at the back), is commonly found in climbing birds such as woodpeckers and parrots. The evaluation methods for these models included a qualitative variable-object grasp assessment. The results highlighted design features that suggest an improved grasp: a small and central palm, curved distal digit components, and a symmetrical digit arrangement. A quantitative grip force test demonstrated that the single digit, the anisodactyl claw, and the zygodactyl claw designs support loads up to 64.3 N, 86.1 N, and 74.1 N, respectively. These loads exceed the minimum mechanical load capabilities for prosthetic devices. The developed designs offer insights into how biomimicry can be harnessed to optimize the grasping functionality of upper-limb prostheses.