Recently, rapid urbanization, especially in developing countries, has led to increased carbon emissions owing to the higher utilization rates of construction machinery. In response, the development of carbon emission reduction technologies based on portable emissions measurement systems, along with the adoption of eco-friendly powertrains, such as hybrid and hydrogen engines, has drawn increasing attention. However, to achieve performance comparable to that of conventional diesel engines, the installation of additional equipment, such as large fuel cell stacks and hydrogen fuel tanks, is required. This leads to an increased curb weight, which can reduce energy efficiency. Therefore, in this study, the structural design was optimized to ensure the structural safety of the track frame that connects the upper and lower chassis components of an excavator to compensate for the added weight of an eco-friendly powertrain and achieve vehicle weight reduction. Through topology optimization of the lattice structures of the track frame based on the density method, a configuration was designed that distributes the additional weight of the upper body. Furthermore, a design of experiments method was employed to derive linear regression equations for each performance indicator. Based on these e...