## 3 Research Approach  
The research in this study has been based on an in-depth qualitative study using action research spanning five manufacturing companies, which all have both discrete and continuous parts in their production processes, located in Sweden. It would have been possible to use other iterative, agile or spiral models having iterated refinement of the research results. However, action research was deemed as a good fit due to its flexibility and the possibility to use various data collection and analytic methods. The companies involved in the study were from the vehicle parts, vehicle, pre-fabricated building and laminate floor industries. The names of the companies, except Gestamp HardTech AB, which is a producer of press-hardened vehicle parts, are kept confidential as agreed. All of the companies have R&D capabilities within Sweden, which was a requirement to participate in the study. The research targeted in this paper is the third cycle's first and second phases, i.e., diagnosing and planning action, of an action research [30] effort where the researchers have had the roles of external experts and consultants and internal experts. The total research effort, in order to reach \"full\" ZDM,is foreseen to be 5 cycles. This research was conducted as part of the first (out of three) steps in the Swedish Innovation Agency VINNOVA's program for challenge-driven innovation. Further, each cycle includes 4 phases as outlined below. Prior to this third cycle, two cycles of action research have been conducted at Gestamp HardTech AB (cf. [7, 8]). A literature review, concerning finding new ideas, approaches and research since the second cycle ended, was part of the first phase, and its result was used as input to the diagnosis. Action research has been defined as \"a participatory, democratic process concerned with developing practical knowing in the pursuit of worthwhile human purposes, grounded in a participatory worldview which we believe is emerging at this historical moment. It seeks to bring together action and reflection, theory and practice, in participation with others, in the pursuit of practical solutions to issues of pressing concern to people, and more generally the flourishing of individual persons and their communities\" [30]. The characteristics of action research are:  
1. that action researchers act in the studied situations, and
2. that action research involves two goals. The goals pertain to solving the problem (the role of the consultant) and making a contribution to knowledge (the role of the researcher); further, that action research requires interaction and cooperation between researchers and the client personnel and, finally, that action research can include all types of data gathering methods [31]. In accordance with [32], the action research approach encompasses 4 phases: diagnosing, planning action, taking action and evaluating the action in relation to a certain context and specific purpose. The third cycle's first and second phases were completed with an iterative and reflective case management methodology. The data pertaining to the first phase, i.e., mainly technical, methodological and organizational needs for change, were collected during a workshop or site visit [33] at each of the companies (commonly involving 3-8 key respondents from the R&D, production and maintenance departments at each workshop) and a following semi-structured open-ended interview ([34, 35]) with key respondents (e.g., R&D managers, development managers, IT and automation engineers, and senior researchers or development engineers) at each company. The workshops, site visits and interviews were conducted during 2019. The respondents were well aware of and knowledgeable regarding production systems and equipment, predictive maintenance, quality control, sensors and input-output measurements. Semi-structured interviews with open-ended questions ([34, 35]) were used after the workshops and site visits to collect data.