Astronauts may soon be moving more naturally on the Moon and Mars thanks to a soft robotic exosuit developed by researchers at the University of Bristol. The wearable trousers, designed to be worn under a spacesuit, aim to reduce lower-limb fatigue while supporting everyday mobility tasks in reduced gravity environments.
“It feels very strange,” said Bristol researcher Emanuele Pulvirenti while demonstrating the exosuit to Reuters. “It’s like having an added layer of muscles. So your own muscles are not working as hard… it almost feels like someone is giving you a little push to move just a little bit easier.”
Dual Functionality for Mobility and Muscle Maintenance
The team is developing two versions of the exosuit: an assistive variant to help astronauts move in pressurised suits, and a resistive version that adds load to maintain muscle mass. The ultimate goal is to integrate both functions into a single, garment-like exosuit. Pulvirenti noted that the technology could also have applications on Earth, including rehabilitation systems that either assist movement or provide resistance to preserve muscle strength.
The exosuit uses inflatable artificial muscles combining an outer nylon layer with an inner thermoplastic layer for airtight inflation. Key structural elements, such as the waistband and knee straps, are reinforced with Kevlar for durability.
Field Trials Show Promising Results
In October 2025, the exosuit was tested at the University of Adelaide’s Exterres CRATER facility, a simulated lunar environment. Integrated into a spacesuit, it was evaluated during walking, climbing, and carrying loads on loose terrain. Pulvirenti said both subjective feedback and scientific data—including measurements of muscle activation and joint kinematics—confirmed the suit’s effectiveness.
Addressing the Challenges of Reduced Gravity
Pressurised suits can restrict natural leg motion, increasing fatigue during planetary surface operations. Combined with reduced gravity, astronauts’ muscles can weaken rapidly, requiring time-consuming daily exercise to maintain fitness. The soft robotic exosuit is designed to provide dynamic loading throughout the day, complementing traditional exercise regimes and helping crews maintain “Earth-ready” muscle strength during long-duration missions.
