The success of a product in the market is largely defined by the quality of design decisions made during the early stages of development. The product design requires designers to balance multiple objectives such as functionality, cost, and user satisfaction, while addressing the challenges posed by increasing product variants and customization demands. To tackle these challenges, one approach is to structure a comprehensive model that incorporates design for assembly (DFA) guidelines during the formulation of product architecture in the conceptual phase of development. While numerous strategies have been proposed in the literature, information is often scattered, making it difficult for readers to gain a comprehensive understanding of the topic. This paper systematically reviews the role and impact of DFA in product development, consolidating and presenting the information coherently. The review provides an overview of the methods developed, along with their potential benefits and limitations. A common framework is identified that defines the structure of the models, helping designers integrate assembly consideration into their design processes, thus reducing assembly time, cost, and complexity. The framework describes the operational setting, including the domain and context in which models operate, and offers a classification of possible methods and desired outputs. Additionally, the review identifies the industry in which case studies have been most frequently presented, and the software used to facilitate the process. By connecting with such a framework, future models can be created following a structured approach, and existing models can be classified and upgraded accordingly.

This study examines barriers to integrating design for assembly (DFA) principles into modular product architectures using the modular function deployment (MFD) method–a critical step for enabling cost-efficient mass customisation. Despite the known benefits of DFA, its adoption in early design stages remains limited. Drawing on qualitative insights from a focus group involving industry practitioners and advanced engineering students, as well as a prior systematic literature review, the study identifies key challenges. Results are classified into primary–closely aligned with research gaps–and secondary themes, emerging during practice-based discussions. These findings are synthesised into a conceptual framework structured around technological, economic, regulatory, and organisational (TERO) barriers. The framework provides guidance for integrating DFA earlier in modularisation, supporting more efficient, adaptable, and high-quality designs. It also outlines actionable areas for future research, including early-stage evaluation methods, AI-augmented design practices, and strategies for structuring knowledge repositories and promoting cross-functional collaboration.

This study, conducted with Northvolt, examines battery system recyclability and disassembly dynamics. It introduces indices for material and product recyclability, along with disassembly time assessment. The goal is to create a design tool to streamline the evaluation of battery disassembly, aiding in designing recyclable and serviceable components. These methodologies serve as a blueprint for enhancing battery systems' overall sustainability and circularity design, presenting a base for future product development in alignment with environmental and economic objectives.

Modular product design has become a strategic enabler for companies seeking to balance product variety, operational efficiency, and market responsiveness, making the alignment between modularar chitecture and manufacturing considerations increasingly critical. Modular Function Deployment(MFD) is a widely adopted method for defining modular product architectures, yet it lacks systematic support for assembly considerations during early concept and system-level development. This limitation increases the risk of delayed production ramp-up and lifecycle inefficiencies. This paper proposes a set of enhancements to MFD that integrate Design for Assembly (DFA) logic into architectural synthesis. The extended method introduces structured heuristics, assembly-oriented module drivers, a coded interface taxonomy, and quantitative metrics for assessing assembly feasibility and automation readiness. These additions preserve compatibility with standard MFD workflows while enriching decision-making with traceable, production-informed reasoning. An illustrative case study involving a handheld leaf blower demonstrates the method’s usability and effectiveness. The redesigned architecture shows reduced assembly effort, simplified interfaces, and increased automation potential. By supporting early-stage evaluation of architectural alternatives through an assembly lens, the method enables faster transition to efficient volume production and provides a foundation for continuous improvement throughout the product lifecycle.

Modular product architectures are used to enhance flexibility, reduce production complexity, and support sustainability goals. However, traditional Modular Function Deployment (MFD) method does not fully integrate Design for Assembly (DFA) and Design for Disassembly (DFD) principles, leading to sub-optimal manufacturability and end-of-life strategies. This study introduces an expanded MFD method incorporating assembly and disassembly considerations into early-stage modularisation. A workshop-based evaluation assesses usability and applicability, involving participants using standard and expanded MFD. Results indicate that integrating DFA and DFD enhances assembly efficiency, ease of disassembly, and modular product strategy alignment. However, usability challenges were identified, necessitating refinements for industry application.

Modular product architecture creation methods often fail to fully account for assembly constraints, limiting their practical applicability. This challenge is spread across industry but has greater consequences for small- and medium-sized enterprises (SMEs), where design decisions must align with constrained production capabilities. This study examines how the integration of Design for Assembly (DfA) principles into Modular Function Deployment (MFD) can enhance the development of modular product architectures. Through a retrospective, case-based analysis of the Senseair RDS (refrigerant detection system), the research reconstructs key design and organisational decisions and evaluates how a DfA-expanded MFD method could have influenced them. The analysis combines document review, two participatory workshops, and entry–exit surveys to map decisions, challenges, and barriers.

Results show that early modular reasoning was constrained by resource pressure, compliance demands, and departmental separation, leading to duplicated work and late clarification of interfaces. Application of the proposed method highlighted opportunities for earlier identification of assembly trade-offs, clearer justification of architectural choices, and improved cross-functional communication. Participants found the method conceptually useful but effort-intensive, emphasising the need for lightweight training and adaptation to existing SME routines. Mapping of workshop findings to the Technological-Economic-Regulatory-Organisational (TERO) framework revealed that organisational and economic barriers dominate over purely technical ones. The study concludes that structured approaches such as the DfA-MFD method act most effectively as sense-making tools that formalise existing knowledge, promote assembly-oriented design decisions, and support incremental improvement of modular architectures under industrial constraints.