Portable exosuit makes walking and running easier

Researchers at the Harvard Wyss Institute have created a portable exosuit that can assist with gait-specific hip extension during walking and running. The exosuit is made of textile components and is worn at the waist and thighs. The suit also has a mobile actuation system that is attached to the lower back and controlled by an algorithm.

The special algorithm allows the exosuit to robustly detect the transition from walking to running and vice versa. In testing the exosuit worn by users on treadmill-based indoor tests on average reduced their metabolic coasts of walking by 9.3% and for running by 4%. The researchers say they were excited to see that the exosuit performed well when walking uphill and at different running speeds in overground, outdoor testing.

The team admits that the metabolic reduction their exosuit provides are modest; they note that the study demonstrates that it is possible to have a portable, wearable robot assist for more than just a single activity. The team says that its research paves the way for these systems to become ubiquitous in daily life. Development of the exosuit was part of the former DARPA Warrior Web program and is the result of years of research and optimization.

The team notes that a previous multi-joint exosuit it developed that assisted the hip and ankle during walking and a medical version of the suit to help rehab stroke patients are commercially available. The new exosuit is designed to be simpler and lighter weight compared to its past suits. It uses a cable actuation system to assist the user.

The device weighs in at 5kg total with more than 90% of its weight near the body's center of gravity. The team says that one of the biggest challenges was to get the exosuit to distinguish between walking and running gaits and to change actuation profiles accordingly with the right amount of assistance at the right time. The team is now focused on optimizing all aspects of the technology.