Mo Rastgaar, a Michigan Technological University mechanical engineer, and his team have developed a robotic ankle that "sees" where it is going.
The artificial vision system includes a low-cost camera and a computer-controlled actuator, which adjusts the ankle’s position through a system of cables.
The camera identifies the profile of the ground, while the computer uses leg movement to determine the location of the next footstep. The computer then analyzes the information from the camera and applies the correct angle and stiffness to the ankle. Thus, the ankle could adapt precisely, whether the user is climbing stairs or striding over a pothole.
Rastgaar’s team has also made the actuator’s design lighter and more streamlined. Because the foot is moved by lines similar to bicycle brake cables, the actuator does not have to be mounted on the prosthesis, where the user must to move it with every step. Instead, the device can be carried in a pocket or fanny pack.