Pressure simulation and comfort prediction of the interface between the receiving cavity and the residual limb of 3D printed prostheses based on digital twins

Abstract

This study presents an integrated digital twin framework for simulating interface pressure distribution and predicting wearing comfort in 3D-printed prosthetic sockets. The methodology begins with acquiring the residual limb’s geometric data through high-precision 3D scanning, followed by establishing a nonlinear hyperelastic material model to represent the mechanical behavior of soft tissues. The CAD model of the personalized socket is then assembled, and the prosthetic donning process is simulated using finite element analysis to compute stress/strain distributions within the residual limb. To enhance predictive accuracy, experimental validation is conducted using a thin-film pressure sensor array that measures actual interface pressure at key anatomical locations during static loading. These measurements are systematically compared with simulation results for model calibration. Subsequently, regression models are developed to establish quantitative relationships between pressure distribution metrics derived from simulations and subjective comfort scores obtained from clinical evaluations. The research demonstrates a closed-loop “simulation-measurement” approach that integrates digital twin technology into the prosthetic design process. This methodology enables reliable comfort prediction for new socket designs while significantly reducing dependence on physical fitting trials. The validated framework offers substantial potential for improving both the design efficiency of prosthetic sockets and the overall wearing comfort for amputees, representing an important advancement toward digitalized and personalized prosthetic rehabilitation solutions.