High-precision Positioning and Real-time Data Processing of UAV-Systems
- 1. High-precision Positioning and Real-time Data Processing of UAV-Systems Matthes Rieke, Theodor Foerster, Jakob Geipel, Torsten Prinz Institute for Geoinformatics – University of Muenster UAV-g 2011 Conference – September 16, 2011 – Zurich, Switzerland http://purl.net/ifgi/copter
- 2. Sensor platforms ● Current available UAV systems use common GPS receivers ● Not addressing use cases where high position accuracy is inevitable ● Creating orthophos using Direct Georeferencing 2 http://purl.net/ifgi/copter
- 3. Approach for improving position accuracy • Micro- or small-sized UAV systems • Improvement using Real Time Kinematic • Prototypical realization using a Microdrones md4-200 • Overview of the used hardware • Conceptual design of data processing software 3 http://purl.net/ifgi/copter
- 4. Teaser of the used hardware 4 http://purl.net/ifgi/copter
- 5. Possible use case • Improve/Enable Direct Georeferencing • Currently limited due to several aspects • Exterior orientation (e.g. low-cost GPS/GNSS, IMU) • Alignment of time of image acquisition and positioning Focus on improving absolute positioning using advanced GNSS techniques + timestamp synchronisation • Stabilize flight trajectory • Decrease the position delta between planned and actual image position 5 http://purl.net/ifgi/copter
- 6. Improving position accuracy on-the-fly REAL TIME KINEMATIC 6 http://purl.net/ifgi/copter
- 7. Real Time Kinematic • Specialized form of Differential GNSS • Ground based Augmentation System • Takes phase observations into account for error estimation • Based on correctional signals from national services 7 http://purl.net/ifgi/copter
- 8. Real Time Kinematic • What do you need? • In general: rather cost-intensive hardware • GNSS receiver + antenna – processing of RTK corrections • Radio modem (e.g. GPRS) to retrieve correction signals • Processing unit for data communication • Payload! 8 http://purl.net/ifgi/copter
- 9. Real Time Kinematics 9 http://purl.net/ifgi/copter
- 10. Benefitting from improved positioning DATA PROCESSING 10 http://purl.net/ifgi/copter
- 11. Software approach ● Software running on groundstation ● Support for different UAV platforms ● Synchronization of multiple data streams to enable real-time measurement capabilities ● Modulized architecture to foster reusability ● Realized using Software Framework 11 http://purl.net/ifgi/copter
- 12. Framework Approach ● Architecture 12 http://purl.net/ifgi/copter
- 13. Framework Approach ● Synchronization of sensor streams ● Why synchronize streams? ● Knowledge of exact position at time of image aquisition ● Currently: interpolation mechanism ● Abstract – easily adjustable for application 13 http://purl.net/ifgi/copter
- 14. Framework Approach ● Basis is description of Plugin Behaviour ● Input/Output phenomena using XML descriptions ● When to determine a position? 14 http://purl.net/ifgi/copter
- 15. Applying in real-world situations RESULTS AND FUTURE WORK 15 http://purl.net/ifgi/copter
- 16. Hardware integration • Currently only DGPS receiver used • Future work involves an RTK-enabled L1/L2 GPS/GLONASS receiver • Problem of moved centroid • Hardware optimization • Implementation of Direct Georeferencing workflow • Move to md4-1000 to gain more payload 16 http://purl.net/ifgi/copter
- 17. Hardware integration 17 http://purl.net/ifgi/copter
- 18. Use case – precision farming Monitoring Precision workflow farming Push-based communication 18 http://purl.net/ifgi/copter
- 19. Source Code available at: 19 http://purl.net/ifgi/copter
- 20. WHAT IS MISSING? 20 http://purl.net/ifgi/copter
- 21. Thank you for your kind attention! Questions? http://purl.net/ifgi/copter Matthes Rieke – m.rieke@uni-muenster.de 21 http://purl.net/ifgi/copter