Table of Contents
About
This project takes inspiration from the muscle’s anatomy in the design and testing of a soft passive ankle orthotic. A low-cost pneumatic actuator worn from the foot to the knee intends to provide dorsi and plantarflexion assistance. Through an air reservoir under the ball of the foot, the system can be passively actuated when stepped on to fill the actuator with air, extending it. Overall, the system was able to provide dorsiflexion assistance and a slight reduction in muscle effort. Verification of the system was done through filtered EMG and goniometer data, as well as force plate response to heel strikes.
For more information and visualization refer to the Final Slideshow.
Keywords
Bioinspiration, Wearable Device, Rapid Prototyping, EMG, Gait Analysis
Abstract
This paper introduces a novel wearable ankle device that provides assistance to a human user while walking. The device has two main components: a pneumatic artificial muscle (PAM) that provides assistive torque in the sagittal plane, and an air reservoir under the foot that, when stepped on, causes the PAM to actuate. Therefore, this device is passive and does not require any air compressor or power source to actuate, and the actuation timing is determined by the placement of the reservoir under the foot. A prototype of this device was modeled, fabricated, and then tested in an experiment that aimed to determine if the device could provide assistance while walking. The preliminary study on one subject demonstrated strong potential for the device, since it was shown that the actuator successfully provided dorsiflexion assistance. There was also an indication of a slight reduction in muscle effort required for dorsiflexion. The results also indicated design changes, such as the reservoir placement and design, for future iterations of this device. Overall, the device demonstrated potential for being a lightweight and low-cost device that could be more accessible than current state-of-the-art robotic devices, but more functional than commonly used ankle foot orthoses.
System Demo Video
Video demonstrating the Active state of a subject wearing and walking with the device.