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The WingtraOne VTOL UAV integrated with the Septentrio AsteRx GNSS receiver overcomes challenges in floodplain surveying in Illinois, USA, with RTK centimeter-level positioning, providing high-precision data support for solar power plant site selection.
Project Challenges：High-precision floodplain surveying under GNSS interference and severe weather conditions
The floodplain at the confluence of the Mississippi River and Ohio River in Illinois, USA, is a planned site for a large energy company’s solar power plant. This area is prone to surface flooding during the rainy season, coinciding with strong winds in the river delta. Severe weather combined with potential GNSS interference poses dual challenges to survey operations.
BFW Engineering & Testing, hired for the project, needed to obtain accurate elevation data and digital terrain models within a limited operational window. High-precision data was required to mitigate flood risks to future power plant facilities, ensure operational efficiency and on-site personnel safety, and support the precise layout of solar panels and related equipment. Such stringent requirements for accuracy and reliability far exceeded the capabilities of conventional survey equipment.
Solution：WingtraOne UAV integrated with Septentrio technology
BFW Engineering & Testing selected the WingtraOne Vertical Take-Off and Landing (VTOL) UAV powered by Septentrio as its core technology to build a high-efficiency survey solution:
Core Hardware Integration:
WingtraOne UAV equipped with the Septentrio AsteRx multi-frequency GNSS receiver and Sony QX1 imaging system ensures data acquisition accuracy from the source.
Harsh Environment Adaptability:
The UAV’s autonomous take-off and landing capability reduces on-site personnel exposure. Operations can continue even when the survey window is shortened by weather conditions.
Dual-Mode Data Assurance:
Real-time RTK (Real-Time Kinematic) positioning + PPK (Post-Processing Kinematic) mode maintains data accuracy even without signal connectivity.
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Key Enabling Technologies: Enhanced Core Strengths of Septentrio
RTK Centimeter-Level Positioning
The AsteRx receiver natively supports RTK technology, delivering centimeter-level geotagging and precise photo time synchronization for reliable survey data. It also enables PPK post-processing when real-time connection is unavailable, maintaining consistent centimeter-level accuracy to support high-precision mapping and solar farm site selection.
AIM+ Interference Mitigation
Exclusive AIM+ interference mitigation technology actively defends against radio frequency interference in complex electromagnetic environments. It ensures stable, continuous GNSS signal reception even in challenging areas, eliminating signal loss or positioning errors caused by external interference during critical survey missions.
Deep UAV Compatibility & Reliability
The receiver is fully optimized for WingtraOne VTOL UAVs, supporting fully autonomous flight, vertical takeoff and landing, and long-endurance missions. It enhances flight stability and data acquisition reliability under harsh conditions such as strong winds and flooding, improving operational safety while securing high-quality survey results.
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Project Outcomes：Precision Surveying Enabled by Septentrio Technology
After several days of survey operations, BFW achieved remarkable results in complex environments using this solution:
Compliant GNSS Data Accuracy:
Image data processed via Pix4D software delivered elevation information and digital terrain models with an average accuracy of 4.5 cm, fully meeting the precision requirements for solar power plant site planning.
Effective Flood Risk Mitigation:
High-precision GNSS survey data allowed the energy company to optimize the layout of solar panels and supporting infrastructure, preventing potential flood damage costs from the design stage.
Efficient and Safe Operations:
Autonomous UAV operations greatly reduced safety risks from high winds and rainy conditions. The survey was completed efficiently even within a shortened weather window. Jacob Cash, Mobile Mapping Manager at BFW, highly commended the solution for its reliability and safety.
Summary：Septentrio: The Core Enabler of Professional Surveying
Septentrio is more than a hardware provider. Through core technologies including the AsteRx GNSS receiver and AIM+ interference mitigation, Septentrio acts as the “performance engine” of WingtraOne UAVs — helping integrators overcome survey bottlenecks in harsh floodplain environments while delivering reliable technical support for engineering projects such as energy site selection. This reinforces Septentrio’s mission to empower integrators to create value.
Why is this solution adaptable to harsh floodplain environments?
The key lies in the AIM+ interference mitigation technology of the Septentrio AsteRx receiver and the UAV’s autonomous flight capability, which counteract both RF interference and strong winds simultaneously. The RTK/PPK dual mode further guarantees GNSS data accuracy, ensuring reliable operations in complex environments.
How does survey data accuracy meet solar power plant site selection requirements?
Leveraging the centimeter-level RTK positioning of the AsteRx GNSS receiver and processing with professional Pix4D software, the final terrain data achieves 4.5 cm accuracy. This precisely identifies flood-prone zones and provides a reliable data foundation for power plant facility layout.
What are the core advantages of the WingtraOne UAV integrated with the Septentrio AsteRx GNSS receiver compared with ordinary surveying equipment?
Its core advantages lie in both centimeter-level positioning accuracy and adaptability to complex environments. Relying on RTK technology for accurate data collection and AIM+ anti-jamming technology to resist radio frequency interference, combined with the autonomous take-off and landing capability of the UAV, it can operate efficiently in harsh conditions such as rainy seasons in floodplains and strong winds while ensuring personnel safety, addressing the pain points that ordinary equipment can hardly adapt to.
How exactly do the high-precision data output by this surveying solution support the site selection of solar power plants?
The solution outputs elevation information and digital terrain models with an average accuracy of 4.5 cm. Based on these data, energy companies can accurately identify flood-prone areas in floodplains, optimize the layout of solar panels and supporting devices, avoid the risk of flood damage to power plant facilities from the source, and meet the requirements for precise panel layout, providing reliable data support for site selection and planning.
