In a study published in April in Advances in Mechanical Engineering, researchers described their design and evaluation of an actuated finger prosthesis that is powered from the medial phalanx portion of the finger. The prosthesis, sized to match the 50th percentile female index finger and weighted like a natural finger, can generate pinch forces comparable to those of commercial powered fingers at flexion speeds that exceed those of existing devices, according to the study. The researchers noted that existing externally powered devices typically house both motor and gear transmission in the proximal phalanx, which they believe provides function at the expense of anthropomorphism.
The device’s transmission was manufactured with a high-strength maraging steel alloy and direct laser metal sintering and connected to a DC motor, which accommodates joint movement at the proximal interphalangeal joint.
To read the open-access study, visit “Design and evaluation of a distally actuated powered finger prosthesis with self-contained transmission for individuals with partial hand loss.”