A Spring Boot REST API and web-based visualization platform for querying and exploring the OPEVA Electrified Automotive (E-Auto) ontology via SPARQL. The platform integrates experimental results from across the OPEVA demonstrations into a shared knowledge graph, enabling semantic interoperability and KPI-driven data exploration.
This project is part of the OPEVA (OPtimization of Electric Vehicle Autonomy) European project, funded within the Key Digital Technologies Joint Undertaking (KDT JU) from the European Union's Horizon Europe Programme.
The OPEVA E-Auto ontology is publicly accessible at: https://cloud.erarge.com.tr/ontologies/eauto
The ontology is grounded in W3C SOSA/SSN for sensor observations and QUDT for units of measurement. A separate routing ontology for Demo 5 is integrated at https://cloud.erarge.com.tr/ontologies/opeva_demo5.
The platform provides dedicated pages for eight OPEVA demonstrations:
| Demo | Topic |
|---|---|
| Demo 1 | HiL Battery Balancing |
| Demo 2 | Battery Pack with Smart BMS |
| Demo 3 | Improved Sensors / EIS Monitoring |
| Demo 4 | Digital Twin for EV Performance |
| Demo 5 | Energy-Efficient Route Planning |
| Demo 6 & 8 | Inductive Charging Integration |
| Demo 7 | Functional Safety — Anomaly Detection |
| Demo 9 | Flexible Charging Scheduler |
| Demo 10 | AI-Powered Digital Twin for Real-Time Collision Prediction |
Each demo page executes live SPARQL queries against the knowledge graph, displays KPI summaries and interactive charts, and allows downloading the result dataset as CSV or JSON.
- Spring Boot 3.3.0 / Java 20
- Apache Jena — RDF and SPARQL processing
- Virtuoso Triplestore — RDF storage and SPARQL engine
- Chart.js — data visualisation
- Leaflet — geographic route maps (Demo 5)
POST /sparql
Content-Type: text/plain
Executes a raw SPARQL SELECT query against the triple store. The following prefixes are injected automatically:
PREFIX eauto: <https://cloud.erarge.com.tr/ontologies/eauto#>
PREFIX sosa: <http://www.w3.org/ns/sosa/>
PREFIX ssn: <http://www.w3.org/ns/ssn/>
PREFIX qudt: <http://qudt.org/1.1/schema/qudt#>
PREFIX rdf: <http://www.w3.org/1999/02/22-rdf-syntax-ns#>
PREFIX xsd: <http://www.w3.org/2001/XMLSchema#>Returns a JSON array where each object represents a result row with SPARQL variable names as keys.
Each demonstration exposes one or more endpoints under /api/demo{N}/... returning structured JSON with KPI summaries and data series ready for charting.
- Java 20+
- Maven 3.6+
- Access to a Virtuoso instance loaded with the OPEVA graphs
Copy the example properties file and fill in your Virtuoso connection details:
cp src/main/resources/application.properties.example src/main/resources/application.propertiesmvn spring-boot:runThe application starts on http://localhost:8080 by default. The home page provides an interactive hotspot diagram linking to all demonstration pages.