Upscaling ocean observation with standardized modular Open Hardware - The Open Source Building Kit

Ocean observation urgently needs scalable, affordable solutions that increase spatial and temporal coverage, especially in coastal and data-poor regions. The study presents the Open Source Building Kit (OSBK), developed within the SOOP innovation platform, as a modular open-hardware–software framework to simplify deployment, integration, and community uptake of marine sensors. The paper evaluates OSBK against DIN SPEC 3105, the first officially accredited Open Hardware standard in Germany, to assess practical suitability for research and citizen science contexts. A sequential mixed-methods design is applied: (i) a semi-structured expert interview to elicit goals, challenges and perceived gaps in standardization; (ii) a requirements analysis mapping OSBK documentation criteria according to DIN SPEC 3105; and (iii) developer feedback via structured questionnaire aligned with those criteria. Findings indicate that DIN SPEC 3105 broadly matches real-world documentation needs and fosters reproducibility and long-term maintainability, but entry barriers persist: fragmented guidance, ambiguities in required detail, limited coverage of modular systems and uneven linkage between hardware and software artifacts. Proposed are actionable improvements – concise checklists and examples, clearer definitions, accommodation of modular architectures, and stronger hardware–software harmonization. Summarized, standardized Open Hardware can lower costs and expand participation, ultimately strengthening marine observing capacity.