An axiomatic design model for manufacturing process selection through a holistic assessment of technology capabilities : a case study in additive manufacturing for rehabilitation medical devices

Abstract

Manufacturing considerations made at the Task Clarification design phase directly impact the number of design iterations prior to fabricating an artefact. This is because designing an artefact with the intended manufacturing process in mind, helps prevent the need for design modifications and subsequent rework later in the design process. Meanwhile, a clear mapping of user requirements plays a crucial role in informing the various design decisions and manufacturing considerations made in the design process. This doctoral work focuses on the design of Rehabilitation Medical Devices (RMDs), highlighting the need to consider a number of Functional and Non-Functional Requirements when designing RMDs. Design teams frequently rely on the expertise of design engineers to formulate product requirements, often with limited consultation from the affected users. When exploring viable manufacturing process options aligned with the identified requirements, technical teams are often drawn towards selecting processes based on their own expertise and current industry practices. Consequently, alternative manufacturing technologies which are suitable to fabricate the artefact are often overlooked. The conducted literature review shows that design teams lack enough knowledge to incorporate a holistic set of requirements used to generate Design Parameters and Process Variables to realise Manufacturing Process Selection (MPS). In view of the above, this research seeks to provide design teams with the necessary support at the Task Clarification design phase towards realising MPS based on a comprehensive set of requirements. An Axiomatic Design model for MPS is proposed (AXIDEM), allowing the selection of manufacturing processes by means of a holistic assessment of Technology Capabilities (TCs). As the main contribution to knowledge, AXIDEM enables design teams to incorporate both Functional and Non-Functional Requirements derived from multiple users, facilitating requirements mapping onto relevant TCs to select a suitable technology early in design to fabricate an RMD artefact. The assessment of the AXIDEM solution revealed that design teams are willing to adopt the proposed solution during the Task Clarification phase of the RMD design process. Yet, the findings suggest that further work is necessary to validate the solution before this can be adopted in design practice.