Investigation of pressure map distribution for the design of an ergonomic cushion through computer-aided engineering

Prolonged occupational sedentary behavior is associated with musculoskeletal disorders and pressure ulcers, consequently diminishing quality of life and productivity. Current ergonomic cushions frequently lack a design foundation grounded in user-specific pressure data. This study developed and validated a methodology for optimizing such cushions, reversing the traditional approach by utilizing pressure mapping analysis as the initial stage. Pressure maps in a sitting position (flat surface, three postures) were characterized for 40 males (age: 25.25 ± 4.00 years; Body Mass Index: 23.83 ± 3.93 kg/m²) using a CONFORMat® software. The average pressure (12.67 ± 4.17 kPa, 12.93 ± 4.31 kPa, and 12.00 ± 3.62 kPa for the three postures, respectively) exhibited no significant variations between postures (Kruskal-Wallis, p > 0.05). These data served as the foundation for the design, which integrated Taguchi method optimization (varying geometry, thickness, and material) and the prediction of mechanical behavior through finite element analysis. The methodology resulted in a cushion design (square, viscoelastic foam) that, validated by simulation and experimental prototypes, demonstrated a more uniform pressure distribution, a reduction in average pressure, an increased contact area, and a preference expressed by the experimental group. The primary contribution lies in the proposal and validation of a methodological workflow that prioritizes pressure map analysis to inform ergonomic design, thereby offering a systematic approach to enhance the effectiveness of cushions and mitigate the adverse effects of sedentary behavior.