Abstract
Hand tool design should integrate the concept of Inclusive Design to be accessible to most users. However, current Inclusive Design strategies of product development are mostly used in post-design evaluation. The retention of inclusive properties in product when new functions are incorporated is essential. Fine operation-aid screwdrivers are designed according to user requirements to address frequently-encountered problems when using screwdrivers namely-insufficient lighting and difficulty in properly installing screws respectively. TRIZ method is applied, comprised the improving parameters solving the problems and worsening parameters which prevents the original inclusive design factors from being damaged into the contradiction matrix, and obtains a set of innovation principles. Eight experts were consulted for their design ideas and developed two fine operation-aid screwdrivers embracing the concept of Inclusive Design. Furthermore, factors regarding the two major operating problems were added to an existing hand tools Inclusive Design Scale. After correlation analysis, the inclusive fine operation-aid screwdriver evaluation scale was established. In addition, two more screwdrivers were selected with the same functions and high reviews on the market as control samples, and 39 users were recruited using a quota sampling strategy to participate in Inclusive Design evaluations. The results revealed that the fine operation-aid screwdrivers evidently solved the two major operating problems in terms of the five dimensions including functionality, comfort, professionality, safety, and usability in the inclusive fine operation-aid screwdriver evaluation scale, thereby affirming the rationality and reliability of our hand tool development approach.