Comparative Finite Element Analysis of Structural Materials for the development of a Mechanically Adjustable and Ergonomic Seating System

System performance, longevity, and user safety are all greatly impacted by the structural material selection made when designing systems for ergonomic applications. Using a mechanically realistic seating mechanism as a standard case study, this work offers a simulation-driven comparative assessment of engineering materials used in ergonomic structural systems, where comfort, safety, and long-term mechanical reliability are essential. The main objective of this project is to assess the mechanical behaviour of particular engineering materials under practical loading scenarios.Four potential structural materials-cast iron, stainless steel, mild steel, and aluminium alloy were modeled in ANSYS Workbench and put through a consistent human loading process. The meshing, boundary conditions and geometry were applied uniformly throughout all simulations. Von Mises stress, total deformation, elastic strain, and stress intensity are the main mechanical outcomes that were assessed. In order to determine how dependable materials are to cyclic load under long-term use, fatigue life analysis was also carried out, but only for materials having available S-N curves.Simulation results showed that mild steel provides the best mix of stiffness, yield performance and fatigue endurance, whereas aluminium gives a notable weight advantage at the cost of decreased structural stability. In contrast to cast iron, which fared badly in both its deformation and stress requirements, stainless steel demonstrated a moderate level of mechanical integrity, although its cost and fatigue are notable drawbacks. The most ergonomic application was ultimately chosen and ranked after taking availability and cost research into account.This study offers a solid framework for choosing structural materials in the development of ergonomic products that is based on mechanics. For engineers and designers looking to combine affordability, durability, and strength in human-centered design systems, it provides evidence-based advice.