## 5 Towards a Standardized Framework for Digital TPM Implementation
### Performance Evaluation Using Standardized Metrics  
Ultimately, the effectiveness of any TPM 4.0 initiative lies in its ability to demonstrate tangible impact through clearly defined performance metrics. To this end, the standardized framework must incorporate a core set of indicators that align operational outcomes with strategic objectives. Key among these is OEE, a synthetic KPI that captures availability, performance, and quality in a single measure. Complementing this, MTBF and MTTR provide insights into equipment reliability and maintainability. The Digital Adoption Rate, which reflects the percentage of staff actively using digital TPM tools, offers a measure of cultural integration and user engagement. In addition, Alert-to-Intervention Time is essential for evaluating real-time responsiveness and operational agility.  
These metrics should be continuously monitored via digital dashboards and directly connected to broader business goals. Furthermore, integrating feedback loops, especially those powered by machine learning, enables the dynamic refinement of maintenance policies and operational strategies over time. Beyond their evaluative function, these standardized indicators also serve as a communication tool, fostering alignment across departments and improving transparency with external stakeholders.  
Bringing these elements together, the successful implementation of TPM 4.0 requires more than the adoption of advanced technologies, it demands a holistic, structured, and inclusive approach. A robust digital TPM framework must integrate modular technological architectures, a phased deployment methodology, active workforce involvement, and performance monitoring grounded in standardized metrics. By aligning these four dimensions, organizations can ensure not only technical efficiency but also cultural integration, strategic coherence, and long-term adaptability. Ultimately, such a framework positions TPM 4.0 as a catalyst for operational excellence in the digital era, particularly when tailored to the constraints and opportunities of diverse industrial contexts, including SMEs.  
To support this framework, a SysML requirements diagram was developed to formalize and structure the key elements of TPM 4.0 implementation. As demonstrated in the Figure 8 below, the diagram organizes the four main dimensions into hierarchical requirements, highlighting their internal structure and interdependencies. This model enhances clarity and traceability, and provides a foundation for system design and implementation alignment.  
Figure 8: Structured representation of TPM 4.0’s implementation requirements.  
Although the proposed framework brings together the essential components for standardizing digital TPM implementation, certain limitations must be considered to better understand the potential constraints and challenges that may arise in its practical applications. First, industrial requirements vary significantly across sectors, which may affect the direct applicability of the framework without contextual adaptation. What works in the automotive industry, for example, may not be fully suitable for the food or chemical sector due to different regulatory, operational, and technical constraints. Second, human factors and resistance to organizational change remain critical challenges in the adoption of digital practices. Even well-designed technical solutions can face significant barriers if the workforce is not adequately engaged or trained. Third, the limited willingness of some industrial companies to collaborate with academic research poses a barrier to the empirical validation and iterative improvement of the model. Without access to real-world case studies and implementation environments, the framework cannot yet be tested or refined in practice. However, these limitations do not diminish the relevance of the framework, but rather, emphasize the importance of future efforts to tailor and test it through stronger industry-academia partnerships.