EXiO-A Brain-Controlled Lower Limb Exoskeleton for Rhesus Macaques.

Area of Science:

• Neuroscience
• Robotics
• Biomedical Engineering

Background:

• Brain-machine interfaces (BMIs) offer significant potential for rehabilitation and prosthetic applications.
• Developing effective BMIs requires sophisticated control systems and mechanical devices.
• Previous research has explored various BMI applications, but lower-limb exoskeleton control remains a challenge.

Purpose of the Study:

• To present a proof-of-concept for a locomotor brain-machine interface (BMI) using a lower-limb exoskeleton controlled by intracortical activity.
• To describe the mechanical design, innovative features, and initial experimental results of the exoskeleton.
• To lay the groundwork for future advancements in BMI-controlled devices for primates and humans.

Main Methods:

• An awake behaving rhesus macaque controlled a bipedal exoskeleton via intracortical brain activity.
• The exoskeleton featured high output torque, backdrivable actuation, size adjustability, and a safe user-robot interface.
• A novel rope transmission was implemented and the exoskeleton underwent mechanical assessment for transparency, efficiency, stiffness, and tracking performance.

Main Results:

• The exoskeleton successfully moved the macaque's legs based on decoded brain signals while the animal remained physically passive.
• Mechanical assessment provided quantifiable data on the exoskeleton's performance characteristics.
• The device demonstrated capability under both brain control and automated actuation, meeting application demands.

Conclusions:

• The developed lower-limb exoskeleton controlled by a brain-machine interface is a viable proof-of-concept.
• The exoskeleton's design and performance meet the demanding requirements for primate-controlled locomotion.
• This work advances the development of BMI-controlled assistive devices for primates, paving the way for human applications.