Recently, the essence of the value of artefacts has been recaptured from value-in-exchange to value-in-use. Because such value is subjectively evaluated based on the perceived function of users, the designers should improve their value through the circular design process, in which designers repeatedly reflect on and redefine artifact functions by referring to the information related to users' received functions. However, previous functional modelling methods have not addressed the comprehensive structure of functions that clarifies the relationship between provided functions and received functions. This gap causes the difficulty to capture the consistency between these functions, thus, the designers struggle to practice reflection and redefinition of artifact functions logically. Based on aforementioned background, this research clarifies the comprehensive structure that enables understanding of the relationship between provided functions and received functions. Then, this research develops a method to identify the incompatibility between provided and received functions by modelling the comprehensive structure of these functions in a formal procedure. The proposed method was applied to a design case of water quality improvement equipment, and this result demonstrated that the proposed method can describe the process by which designers reflect and redefine their provided functions with their users' received functions.
The simultaneous and integrated design of a series of products has become extremely important under the diversification of customer demands due to the maturity of society. The complicatedness and associated difficulties of their design activities are caused not only by the diversity of products but also by the entire shape of the supply chain. When viewing such a situation through a chain of parts, intermediate products, and final products, the lineup design problem of intermediate products must be another focus toward enhancing the integrative product performance. The lineup design problem is characterized by the simultaneous design of the ranges where respective products cover and the contents of those products. This paper proposes a two-phase method for the lineup design problems. The method consists of designing a framework and optimizing contents under the framework. The latter phase is formulated as a nested mini-max optimization problem. An effective and efficient optimization scheme is constructed by employing monotonicity analysis. Finally, an application to universal motors is demonstrated for ascertaining the validity and promises of the proposed design method.
There is a close relationship between the vibration generated by cutting and the dynamics of the machining system. The dynamics of the machining system often have anisotropy depending on the machine tool structure and the machining setup. Therefore, the anisotropy of the machining system dynamics to suppress the vibration during cutting is investigated in this study. In this paper, fiber reinforced plastics (FRPs) which is an anisotropic material is focused on, and the effectiveness of a method of changing the dynamics of the mechanical structure only in a specific direction using a unidirectional CFRP plate is experimentally investigated. The investigation results are verified by FEM analysis, and the FEM modeling method of the proposed method is presented. Cutting experiments are conducted to verify the validity of the proposed method.