The History and Future of LEGS

Thanks to modern protective equipment and advanced medical solutions, many service members now survive severe limb injuries that in previous wars would have been lethal. Unfortunately, these injuries can be devastating, requiring amputation, reconstruction, and prosthetics to restore function. Military research and development has taken the lead in addressing these challenges, establishing advanced prosthetic solutions as a top priority to meet the needs of injured service members. One such solution is conceived as a manufacturer-agnostic, interoperable lower extremity gait system (LEGS) to restore ambulatory function. As envisioned, the LEGS system would be adaptively responsive and volitionally controlled by the user and configured to maximize component compatibility through the use of open standards. In this chapter, we summarize the primary concerns and considerations that were addressed as objectives through the LEGS initiative, emphasizing essential design features and componentry, including control, sockets, bus, power, algorithms, and the need for open source and open standards to support meaningful and efficient scientific and technical collaboration. Critical knowledge gaps, capability gaps, component limitations, and nontechnical considerations point to the need for additional research and development. These efforts will require significant funding, commitment, and convergence of scientific and engineering resources. We hope that the knowledge and ideas presented here and throughout this volume will stimulate further progress toward the successful realization of advanced solutions such as LEGS.