We are developing exoskeletons to assist the body in various ways, and seeking to understand how they affect the body. Some specific projects are below:
Self-Balancing Lower Body Exoskeleton
In collaboration with Prof. Alex Leonessa at VT, we are developing a self-balancing 12 DOF lower body exoskeleton intended for people with spinal cord injuries (SCIs). The design will allow people to walk without using crutches and at higher speeds than current exoskeletons for individuals with SCIs.
Exoskeletons to Assist with Lifting
In collaboration with Lowe’s Innovation Labs and the National Science Foundation, we are developing exoskeletons to help workers lift heavy objects more easily, with less strain on their backs. Our initial prototype is a flexible structure using carbon fiber as leaf spring elements, documented in several papers:
Design and preliminary evaluation of a flexible exoskeleton to assist with lifting - SE Chang, T Pesek, TR Pote, J Hull, J Geissinger, AA Simon, MM Alemi, AT Asbeck, Wearable Technologies e10, 2020. (Link);
A Passive Exoskeleton Reduces Peak and Mean EMG During Symmetric and Asymmetric Lifting - MM Alemi, J Geissinger, AA Simon, SE Chang, AT Asbeck, Journal of Electromyography and Kinesiology, 47, 25-34, 2019. (Link)
Kinematic Effects of a Passive Lift-Assistive Exoskeleton - A Simon, MM Alemi, AT Asbeck, Journal of Biomechanics, 2021. (Link)
Exoskeletons for Arm Gravity Compensation
We have also developed a novel way of providing gravity compensation to a person's arm, or a tool held in the hand. This allows for a tool or box to be held at any position, including in front of the body. Alternatively, it can be used to support a person's arm who has arm weakness. Some examples of our prototypes are shown below. Our work is detailed in the papers "A Novel Method and Exoskeletons for Whole-Arm Gravity Compensation" by Josh Hull*, Ranger Turner*, Athulya Simon, and Alan Asbeck, IEEE Access, 8, 143144-143159, 2020. (*=Equal Contributions) (Link) and "Design and preliminary evaluation of two tool support arm exoskeletons with gravity compensation" by Josh Hull*, Ranger Turner*, and Alan Asbeck, Mechanism and Machine Theory 172, 2022. (*=Equal Contributions).
The left three photos show a version of the exoskeleton able to support a user's arm. It can permit a full range of motion, and can be worn under a loose-fitting shirt or jacket. The right-most photo shows our first prototype of a version designed to support a load in the hand. It is powered, so the force can be engaged or disengaged.
More recently, we have made two new versions that can support up to 20 pounds held in the hand: an unpowered version that uses a gas spring and linkage to provide the support force, and a powered version with a motor that can dynamically adjust the force depending on the load.
Here, the passive version is shown fully supporting 20 pounds in a variety of postures.