Mechanical SystemMechanical SystemMechanical System

40 Machined Parts

18 Screws

2 Actuators

2 Batteries

Easy to manufacture,
and repair.

Weighs less than

5.4 Kg

with both knee and ankle joints fitted with a foot attachment.

The Open-Source Leg is a cost-effective solution starting at

$9,000 - $19,000

depending on degrees of freedom and sensing options
when you build it yourself.

The Open-Source Leg's knee and ankle joints are

Mechanically Identical

allowing for easy assembly, repair, and control.

Minimum build height of

451 mm

Measured from the ground to top of the knee pyramid adapter with a flat foot attachment.


Range of motion at the knee joint.



Range of motion at the ankle joint.

Supports Series Elasticity

Both knee and ankle joints can be fitted with custom designed radial springs to provide series elasticity with no added volume.

Learn how to get or make
your own Open-Source Leg!

Read more about how to get started with the Open-Source Leg project by downloading the CAD files, placing an order for the machined parts, and assembling your open-source leg. We have also made detailed video and written tutorials to help you along the way!