Development and Evaluation of a Powered Artificial Gastrocnemius for Transtibial Amputee Gait

Figure 3

Powered artificial gastrocnemius joint. The assembled joint is shown without proximal and distal attachments (a). A color-coded coronal plane section view of the same mechanism is also shown (b), where parts that connect as a rigid body are shaded with the same color. The housing (blue) attaches to the proximal mount that is affixed to the thigh cuff. The pulley (red) rotates with respect to the housing via the main bearing (teal). The output link (green) is affixed to the distal mount that connects to the socket. This link rotates with respect to the pulley via the inner bearing, with the torsional spring connecting the output link to the pulley. The potentiometer measures the relative rotation of the housing and the output link. Hard stops (not shown) are mounted to the pulley assembly and engage with the housing at the limits of joint rotation.

(a)

(b)