This paper study the design and realization of a bionic leg for transfemoral amputation and is a contribution in the development of bionic legs especially in a world where the number of amputees is increasing for several reasons, accidents or illness. The bionic leg presented in this work ensures or approaches as closely as possible the role of the amputated leg of a handicapped person. It guarantees the safety and stability of the user, the comfort as much as possible of the action of walking. It has an aesthetic appearance that approaches as much as possible to the appearance of a natural leg. It is designed under the constraints of guaranteeing the availability of all spare parts for prior maintenance, guaranteeing the adaptability of the leg to angular morphological defects at the legs and ankles of a person, guaranteeing the adaptability of the leg to the rest of the body essentially for the length of the natural leg and being of acceptable purchase cost of possession, of use and maintenance. The design process for this project began first of all with field study with amputees and specialists who treat amputees of this type in order to get precious ideas, especially on the medical side of the reaction of the amputee's body to this types of components. In parallel with these visits, a detailed bibliographic study on the analysis of the human walking cycle and existing prosthesis technologies. Following this study, a functional and technical analysis of a system capable of providing or best approaching walking function of an amputee was developed. This analysis led to a technological choice that meets certain criteria imposed in relation with the amputee and his environment. The chosen solution is then dimensioned and drawn up in a detailed graphic file and is after that constructed.

Keywords: transefemoral amputation, bionic leg, design, biomecanics