Kratos
Resistance training for microgravity
Kratos is a compact pulley machine that gives astronauts real resistance, with a camera that watches every rep and corrects form as they train.
How it worksThe problem
In orbit, the body stops working against anything.
On Earth, every step and every time you stand up loads your bones and muscles. In microgravity that load disappears, and the body starts taking apart what it no longer needs. Without countermeasures, astronauts lose bone density and muscle mass week after week.
Resistance exercise is the main countermeasure, so crews train for hours every day. Current equipment is large and heavy, and nobody is standing next to the astronaut checking that the movement is right.
How it works
Pulleys for load. Vision for form.
Weights are useless when nothing has weight. Kratos replaces them with a pulley system connected to a resistance unit, so the astronaut pulls against a controlled force instead of a mass. A camera tracks the body's joints during every rep and feeds that back into the training.
Load
The resistance unit sets the force on the cable through the pulley.
Move
The astronaut performs the exercise, anchored by a foot restraint.
Track
Computer vision estimates joint positions and angles in real time.
Adjust
The system flags bad form and adapts the load for the next rep.
The loop repeats every rep.
Status
A small team, early on.
Kratos Space is a project by a group of friends in Zürich. We are working out the mechanical design of the pulley system and the vision pipeline for tracking movement in a confined space.
If you work on human spaceflight, exercise physiology, or pose estimation and want to give feedback, we would like to hear from you.
Contact