This paper introduces a virtual laboratory to design prosthetic socket, which integrates a 3D CAD module, named Socket Modelling Assistant (SMA), specifically developed to create the socket digital model, and a CAE system to analyze the stumpsocket interaction. Software tool, named Virtual Socket Lab (VSL), is part of a knowledge-based framework to design lower limb prosthesis centered on digital models of the patient or of his/her anatomical districts. The focus of this paper is on the definition of an automatic simulation procedure to study the stump-socket interaction and validate socket design. We first introduce the new design framework and main features of VSL. Then, we present a state of art on FE models adopted for residual lower-limb and prosthetic socket during last two decades highlighting key issues. Finally, the identified procedure and the integration strategy within SMA are described as well as preliminary results of the experimentation.

The contact pressure at the socket-residual limb interface is the most important parameter to evaluate comfort of leg prosthesis. Experimental works analyzed this parameter for typical postures and during walking of an amputee; but experimental tests require a real prototype of the socket equipped with transducers. To optimize socket design, this work presents a virtual approach based on a digital avatar of the patient wearing lower limb prosthesis. Our approach considers the integration of two different types of simulation: the first one concerns the multi-body gait analysis, the second one the pressure evaluation at the socket-residual limb interface with FE analyses. The paper describes the model used, the simulation tools adopted and their integration. Finally the case study related to patient walking on flat floor is described

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This paper refers to the integration of simulations tools to assess the design of prosthetic devices. We address issues arising when the prosthesis needs to be virtually tested, i.e., the gait of the virtual patient wearing the prosthesis. Therefore, we integrate two different simulation tools: the first one to study the interaction between socket and residual limb during the gait and the second one to analyze the patient’s gait deviations. Combining these numerical analyses, it is possible to investigate the causes of gait deviations and suggest remedies, both related to the prosthesis setup and the socket modeling. To prove the validity of the approach, we implemented a Finite Element Analysis model to analysis the stump-socket contact and we assembled a low cost Motion Capture system to acquire and elaborate patient gait. Preliminary results and remarks conclude the paper.

This paper presents an automatic simulation procedure to study the stump-socket interaction that has been embedded within a software platform specifically developed to design lower limb prosthesis. In particular, it investigates and compares the results obtained by means of FE tools with the experimental data acquired with pressure transducers. A transfemoral (amputation above knee) male amputee has been considered as case study. Numerical simulations have been carried out considering different techniques to acquire the residuum geometry and different socket models. In details, two residuum geometric models were reconstructed starting from MRI images and from 3D scanning to investigate how acquisition techniques influence the final results. Two socket geometric models were taken into account. The first was the patient’s real socket, acquired by 3D scanning; the second one has been modeled using a dedicated CAD system, named Socket Modeling Assistant. The patient’s real socket has been also used to perform the experimental pressure measurements. The experimental data have been acquired by means of the Tekscan F-socket system. Results reached so far allowed identifying main criticalities and future developments to improve the accuracy of the numerical results and make available a full-automated simulation procedure