In this paper, we present the prototype realization of the conceptual design of a fully-passive transfemoral prosthesis. The working principle has been inspired by the power flow in human gait so to achieve an energy efficient device. The main goal of this paper is to validate the concept by implementing in a real prototype. The prototype, in scale 1 : 2 with respect to the average dimensions of an adult human, is based on two storage elements, which are responsible for the energetic coupling between the knee and ankle joints during the swing phase and for the energy storage during the stance phase. The design parameters of the prototype are determined according to the human body and the energetic characteristics of the gait. The construction of the prototype is explained in details together with a test setup that has been built to evaluate the prototype.

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In this paper we present the port-based model of WalkMECH, a fully-passive transfemoral prosthesis prototype that has been designed and realized for normal walking. The model has been implemented in a simulation environment so to analyze the performance of the prosthetic leg in walking experiments and so to enhance the mechanics of the system. The accuracy of the model has been validated by experimental tests with a unilateral amputee participant.

In this study, we present the mechanical design of a prototype of a fully-passive transfemoral prosthesis for normal walking. The conceptual working principle at the basis of the design is inspired by the power flow in human gait, with the main purpose of realizing an energy efficient device. The mechanism is based on three elements, which are responsible of the energetic coupling between the knee and ankle joints. The design parameters of the prototype are determined according to the human body and the natural gait characteristics, in order to mimic the dynamic behavior of a healthy leg. Hereby, we present the construction details of the prototype, which realizes the working principle of the conceptual mechanism.

In this study, we present the implementation of the controller for adapting the energy storage capacity of the WalkMECH according to the different walking speeds and gait characteristics of an amputee. Since the main aim is to keep the design both mechanically and metabolically energyefficient, the actuation system is designed based on the minimal actuation principle. The overall system, called WalkMECHadapt, is evaluated with the experimental test set-up with a healthy subject. Test results show that the system is working sufficiently for adapting the energy storage capacity of the WalkMECHadapt thanks to the simple nature of the controller architecture.