Study on the pressure comfort of elbow guards for older women based on numerical analysis and experimental methods

Purpose This study aims to provide three biomechanical models that are consistent with the arm forces of elderly women and to design elbow guards that are more suitable for their use. Numerical analysis and experimental methods were used to determine the optimal direction for elbow guard design, focusing on fabric type, arm force distribution and comfort thresholds. Design/methodology/approach This paper explores the design of elbow guards for older women through predictive finite element modeling and a systematic experimental approach. First, contact anthropometry was used to measure the arm dimensions of older women. Cluster analysis was applied to categorize arm sizes, laying the foundation for the subsequent selection of subjects for 3D scanning. Second, a 3D scanner was used to obtain the external contours of a representative subject’s arm. Finite element models of the arm and elbow guard were constructed with the arm flexed at three different angles. These models were used to simulate the pressure exerted by the elbow guard on the arm. Next, objective measurements of garment pressure were taken using a homemade elbow guard. Finally, subjective comfort evaluation was carried out using the human clothing experiment method. Comfortable pressure thresholds were determined by establishing a correlation between subjective comfort levels and objective pressure values. Findings The results showed that the developed model effectively predicted the pressure distribution between the elbow guard and the arm. By comparing the simulated pressure distributions of the four materials, it was determined that polyamide and spandex fabrics were the more appropriate materials for the elbow pad design. Additionally, the study pointed out the need to consider the different bending postures of the arm when analyzing pressure, focusing on the amount of pressure control at the elbow of the arm. When the arm’s bending angle ranges between 90° and 180°, the total pressure should remain between a minimum of 2550.0 Pa and a maximum of 4394.4 Pa. Originality/value The theoretical approach of ellipses was used to construct the arm model. Numerical simulations were performed to analyze the pressure distribution for three different arm bending postures, and the simulation results provided useful insights for designers in selecting the optimal fabric type. This study provides a theoretical reference for designing comfortable compression elbow guards, while also addressing garment comfort by establishing accurate garment comfort thresholds to guide designers in understanding the appropriate compression dosage. Highlights (1) The theory related to ellipses is introduced in the construction of the model, unlike other studies. (2) The laws of fabric material, force area and bending angle on pressure distribution were analyzed. (3) Clothing pressure comfort thresholds were determined for three different postures.