About the Open-Source Leg Project

In the United States alone, hundreds of thousands of leg amputees have a reduced quality of life due to persistent mobility limitations. In an effort to alleviate the challenges that amputees face, much time, effort, and money has gone into researching prosthetic leg hardware and control system design. However, advancement in the field of prosthetic leg control strategies has been stunted by lack of a uniform hardware system. Currently, prior to entering control strategy research, a group must design and manufacture its own hardware, which may take many years and hundreds of thousands of dollars. Even once a leg is manufactured and a control system has been implemented, though, the comparison of control systems across the field is confounded by the use of different prosthetic hardware. Thus the entire control systems research field is fragmented across different hardware designs.

With the goal of unifying the research field of prosthetic leg controls, an open source robotic prosthetic leg (OSL) was proposed by the Neurobionics Lab at UM. This OSL is a robust and relatively inexpensive system that can be easily manufactured, assembled, and controlled. Through this website, researchers have access to downloadable hardware and software files so that they can enter the research field without having to design the leg themselves. Ultimately, having a ubiquitous leg will help facilitate comparison between control strategies, potentially streamlining the field towards highly functional robotic prosthetic legs.

Thus, the three main goals of the project are as follows:

  1. Identify an electromechanical design for a low cost, high performance, open-source robotic knee and ankle system.
  2. Understand how separate prosthesis control strategies can be combined to benefit amputee gait.
  3. Evaluate the benefit of resulting controllers in amputee experiments; thereby validating the proposed open-source system as a general tool for research on prosthesis control.

The project has leveraged the expertise and facilities of Lead PI Rouse at the University of Michigan — Ann Arbor, PI Gregg at the University of Texas at Dallas, and PI Geyer at Carnegie Mellon University.