Author: Torben Laue
At Fraunhofer Institute for Wind Energy Systems IWES, we work with a wide range of measurement data from various research areas at our nine sites on a daily basis. It includes data from wind measurements and operating data from wind turbines to measurement series from component tests on hydrogen electrolyzers, nacelles and rotor blades or seismic sea floor measurements. Considering this variety of data, it is crucial to develop strategies for the efficient management and use of this data. Vincent Wilms from Fraunhofer IWES has developed the open-source software platform NEXUS for this purpose and made it available to the public. NEXUS can be connected to decentralized data sources and provides users with a central and standardized access point.
Complexity of institute-wide data management
In larger organizations, each team may develop and implement an individual solution for storing their measurement data. With more and more of these isolated solutions emerging, it is becoming more difficult to maintain an overview, as there is no common listing of the data. Interdisciplinary collaboration would also be more difficult, as each data storage system requires individual access for users. The operating and personnel costs increase with each additional system and activities such as setting up access authorizations and data interfaces would have to be carried out several times. Fraunhofer IWES was able to overcome these hurdles by developing and introducing NEXUS.
The IWES solution: NEXUS
NEXUS (“A connection or series of connections linking two or more things”) is an open-source software platform for data management that is used and being continuously improved at Fraunhofer IWES. It offers a central and authorized access point for decentralized data storages, a web interface with an overview of all data (see Figure 1) and standardized data interfaces. This simplifies the day-to-day work of all scientists and reduces costs for the institute, as only one system needs to be maintained.
Figure 2 shows that the NEXUS web interface can also be used to gain an initial insight into the measurement data. NEXUS also offers a standardized data interface in the form of a REST API. This enables scientists to load and save data directly. The REST API can also be used in common programming languages such as Python and MATLAB.
As shown in Figure 3, the storage location of the respective data is arbitrary, as long as it is accessible to NEXUS via the internal network or the Internet. This has the advantage that teams can continue to choose where their data is stored.
NEXUS supports various import and export formats. An extension must be implemented once for each format, which can then be used by all teams. Data formats such as HDF5, CSV and MATLAB and SQL databases as well as various manufacturer-specific formats are already supported.
Cross-site utilization
As all data can be accessed easily via the same access point, interdisciplinary collaboration is possible. The technical implementation of NEXUS also enables a fast connection through local NEXUS instances. Here, relevant data can be retrieved from the main instance and stored temporarily so that scientists can benefit from a fast transfer rate (see Figure 4).
External access
Access to the NEXUS platform can also be set up individually for external parties. This gives us the opportunity to make measurement data available to our customers and project partners. Stakeholders can gain an initial insight into the measurement data via the web interface, as shown in Figure 2.
As the NEXUS software is open-source, it can also be used by other organizations. The advantage of NEXUS is that existing systems such as database servers do not need to be replaced, but simply connected to Nexus.
Increased efficiency through innovative data management
NEXUS is a very good solution for managing our diverse measurement data and plays a key role at Fraunhofer IWES. This is also reflected in the constantly growing size of the development team involved in the further development of the platform. NEXUS greatly simplifies our work processes, and we are keen to share these benefits with a wider audience – so that other organizations can also use NEXUS to gain an overview of their data.
NEXUS is available for free download here: https://github.com/nexus-main/nexus
For questions, please contact Juliane Burfeind, group manager of Software Development. Fraunhofer IWES offers consulting services for potential applications, supports setting up the software, and helps customize NEXUS to the needs of your company.