Exploring the Feasibility of Advanced Manufacturing for Mass Customization of Insoles in the Context of ESG

With the growing demand from the diabetic population and the advancement of lower limb biomechanics, the need for customized insoles for diabetic foot care and lower limb biomechanics correction is rapidly increasing. This has led to a digital transformation in the insole manufacturing process to achieve mass customization. This includes subtractive manufacturing and additive manufacturing. However, the environmental and social impacts of these processes have not been thoroughly assessed. Therefore, this study aims to analyze the ESG (Environmental, Social, and Governance) performance of existing digital processes compared to TP (traditional processes) and identify factors conducive to achieving both mass customization and sustainability. The results indicate that while NC (Numerical Control process) and 3DP (3D printing processes) benefit from digitization by reducing processing time (NC: 69%, 3DP: 38% of the labor hour needed for TP as 100%) and increasing the reliability of process, but NC is limited by energy consumption (TP: 0.39, NC: 0.9, 3DP: 0.32kWh) and manual grinding techniques. In the other hand, traditional process generates the most waste (Waste Weight Percentage: TP: 94.36%, CNC: 87.15%, 3DP) and requires the most processing space. The FFF (fused filament fabrication) type 3DP drastically shortens labor hour and technical barriers, providing an opportunity to change the service model of customized insoles from at least two visits to potentially just one. This makes the 3DP has the best chance to achieve the need of mass customization and the goal of ESG during the digital transformation. Not only the ESG goals but also the metamaterial ability to bring a better function to the insoles. In the future, by the introducing smart material into 4D printing, which can adapt to variable factors and change their structural characteristics, has the potential to enable a single pair of insoles to meet various usage scenarios. Moreover, the concept of 4D printing combined with sensors can elevate the application of insoles from medical usage for preventing or treating illness to daily usage forpredicting illness. This is a goal worth researching further to elevate worldwide healthiness.