![Page 1: VDM-based Navigation for Small UAVs · • As old as GPS (>30 years) • On most UAVs today (outdoor) 3. Introduction. Integrated Inertial and Satellite Navigation (INS -GNSS) INS:](https://reader034.vdocument.in/reader034/viewer/2022050223/5f687a7a90e3a7222c249441/html5/thumbnails/1.jpg)
A New Paradigm forIntegrated Navigation of UAVsBased on Vehicle Dynamic Model
Mehran Khaghani & Jan Skaloud
![Page 2: VDM-based Navigation for Small UAVs · • As old as GPS (>30 years) • On most UAVs today (outdoor) 3. Introduction. Integrated Inertial and Satellite Navigation (INS -GNSS) INS:](https://reader034.vdocument.in/reader034/viewer/2022050223/5f687a7a90e3a7222c249441/html5/thumbnails/2.jpg)
2Introduction
NavigationDetermination of Position, Velocity, and Attitude
X
Y
Z
Position
Velocity
Attitude
![Page 3: VDM-based Navigation for Small UAVs · • As old as GPS (>30 years) • On most UAVs today (outdoor) 3. Introduction. Integrated Inertial and Satellite Navigation (INS -GNSS) INS:](https://reader034.vdocument.in/reader034/viewer/2022050223/5f687a7a90e3a7222c249441/html5/thumbnails/3.jpg)
• As old as GPS (>30 years)• On most UAVs today (outdoor)
3Introduction
Integrated Inertial and Satellite Navigation (INS-GNSS)
INS: Inertial Navigation SystemGNSS: Global Navigation Satellite SystemGPS: Global Positioning System (American GNSS)UAV: Unmanned Aerial VehicleIMU: Inertial Measurement UnitPVA: Position, Velocity, AttitudePVT: Position, Velocity, TimeMEMS: Micro-Electro-Mechanical Systems
MEMS Tactical Navigatione e e>
Problem 1: GNSS outagePVA solution will drift over time
Problem 2: IMU failureNothing will work!
IMU
GNSS
Filter
∫ PVA+
( )PVA∆
PVT
,f ω PVA−
![Page 4: VDM-based Navigation for Small UAVs · • As old as GPS (>30 years) • On most UAVs today (outdoor) 3. Introduction. Integrated Inertial and Satellite Navigation (INS -GNSS) INS:](https://reader034.vdocument.in/reader034/viewer/2022050223/5f687a7a90e3a7222c249441/html5/thumbnails/4.jpg)
4Method
Our Proposition
Aerodynamic
Model
Navigation States
Wind velocity
UAV parameters
Control commands
Rigid Body Dynamics
Linear accelerationForcesMoments Rotational acceleration
Vehicle Dynamic Model (VDM)
Using VDM in navigation
![Page 5: VDM-based Navigation for Small UAVs · • As old as GPS (>30 years) • On most UAVs today (outdoor) 3. Introduction. Integrated Inertial and Satellite Navigation (INS -GNSS) INS:](https://reader034.vdocument.in/reader034/viewer/2022050223/5f687a7a90e3a7222c249441/html5/thumbnails/5.jpg)
5Method
From INS-based to VDM-based Navigation
VDM
GNSS
Filter
∫ PVA+
( )PVA∆
PVT
,f ω
,f ω PVA−
IMU
GNSS
Filter
∫ PVA+
( )PVA∆
PVT
,f ω PVA−
• VDM in process model• Physical constraints• No IMU data integration• Sensor setup• Self calibration• Platform dependence• Higher computational cost
(PC: 1.7 to 2.7 times)
• Platform independence• Low computational cost• Sensor (IMU) in process model
• IMU failure• Physical constraints
+−−
U
∫*nX
++ˆ
nX ˆ nX
ˆ wX
ˆ eX
ˆ pX++ˆ
pX
++
ˆwX
++ˆ
eX
IMUIMUZ
*eXIMU error
model (X )e
*pXParameters
model (X )p
*wXWind
model (X )w
+−
*nX
modelIMUZ
modelGNSSZ
Vehicledynamic
model (X )n nXδ
pXδ
wXδ
eXδ
Sensors(GNSS,Baro, ...)
SensorZ
Filter(e.g., EKF)
![Page 6: VDM-based Navigation for Small UAVs · • As old as GPS (>30 years) • On most UAVs today (outdoor) 3. Introduction. Integrated Inertial and Satellite Navigation (INS -GNSS) INS:](https://reader034.vdocument.in/reader034/viewer/2022050223/5f687a7a90e3a7222c249441/html5/thumbnails/6.jpg)
6Method
Some Other Architectures
IMU
VDM
Filter
∫
∫
( , )b bib∆ f ω ( )VA∆
( )VA∆
PVA∫
∫
( , )b bib∆ f ω
PVA
( , )b bib∆ f ω
Bryson 2004
IMU
VDM
Filter
∫
∫
PVA
( )PVA∆
PVA
Koifman 1999
Current research StillINS-based…
Common issues:• No wind• No self calibration• Partial VDM• No significant improvement
in experiments
![Page 7: VDM-based Navigation for Small UAVs · • As old as GPS (>30 years) • On most UAVs today (outdoor) 3. Introduction. Integrated Inertial and Satellite Navigation (INS -GNSS) INS:](https://reader034.vdocument.in/reader034/viewer/2022050223/5f687a7a90e3a7222c249441/html5/thumbnails/7.jpg)
PixHawk PCLOG
IMU
EKFVDM
Matlab Script
Sensors
GPSAir
Speed BaroGecko 4 Nav
via diff. interfaces
USB/WiFi
On line
Off line
TOPOPlane 2
7Method
Experimental Setup
Payload capacity 0.8 kgFlight endurance 45 minutes
Nominal airspeed 15 m/s
Aircraft & Sensors Connections
![Page 8: VDM-based Navigation for Small UAVs · • As old as GPS (>30 years) • On most UAVs today (outdoor) 3. Introduction. Integrated Inertial and Satellite Navigation (INS -GNSS) INS:](https://reader034.vdocument.in/reader034/viewer/2022050223/5f687a7a90e3a7222c249441/html5/thumbnails/8.jpg)
• Waypoints from real flight• 3D wind velocity from real data• Error statistics of real sensors• Flight simulation Sensor data Reference data
• 100 Monte-Carlo runs
8Results
GNSS Outage: Emulation Scenario
MEMS IMUStandalone GNSS
![Page 9: VDM-based Navigation for Small UAVs · • As old as GPS (>30 years) • On most UAVs today (outdoor) 3. Introduction. Integrated Inertial and Satellite Navigation (INS -GNSS) INS:](https://reader034.vdocument.in/reader034/viewer/2022050223/5f687a7a90e3a7222c249441/html5/thumbnails/9.jpg)
9Results
GNSS Outage: Experimental Scenario
VDM parameters calibration:• On a separate flight:• Start with nominal values in
simulations• IMU and cm-level GNSS data fused• Navigation states as observations• VDM parameters estimated
MEMS IMUStandalone GNSS
![Page 10: VDM-based Navigation for Small UAVs · • As old as GPS (>30 years) • On most UAVs today (outdoor) 3. Introduction. Integrated Inertial and Satellite Navigation (INS -GNSS) INS:](https://reader034.vdocument.in/reader034/viewer/2022050223/5f687a7a90e3a7222c249441/html5/thumbnails/10.jpg)
Emulation
GNSS Outage: Emulation vs Experimental Scenario
10Results
Experiment
53 m
2076 m
38 m
681 m
![Page 11: VDM-based Navigation for Small UAVs · • As old as GPS (>30 years) • On most UAVs today (outdoor) 3. Introduction. Integrated Inertial and Satellite Navigation (INS -GNSS) INS:](https://reader034.vdocument.in/reader034/viewer/2022050223/5f687a7a90e3a7222c249441/html5/thumbnails/11.jpg)
11Results
GNSS Outage: Experimental Scenario
![Page 12: VDM-based Navigation for Small UAVs · • As old as GPS (>30 years) • On most UAVs today (outdoor) 3. Introduction. Integrated Inertial and Satellite Navigation (INS -GNSS) INS:](https://reader034.vdocument.in/reader034/viewer/2022050223/5f687a7a90e3a7222c249441/html5/thumbnails/12.jpg)
• Waypoints from real flight• 3D wind velocity from real data• Error statistics of real sensors• Flight simulation Sensor data Reference data
• 100 Monte-Carlo runs
12Results
IMU failure: Emulation Scenario
MEMS IMUStandalone GNSS
![Page 13: VDM-based Navigation for Small UAVs · • As old as GPS (>30 years) • On most UAVs today (outdoor) 3. Introduction. Integrated Inertial and Satellite Navigation (INS -GNSS) INS:](https://reader034.vdocument.in/reader034/viewer/2022050223/5f687a7a90e3a7222c249441/html5/thumbnails/13.jpg)
13Results
IMU failure: Emulation Scenario100 Monte-Carlo runs
![Page 14: VDM-based Navigation for Small UAVs · • As old as GPS (>30 years) • On most UAVs today (outdoor) 3. Introduction. Integrated Inertial and Satellite Navigation (INS -GNSS) INS:](https://reader034.vdocument.in/reader034/viewer/2022050223/5f687a7a90e3a7222c249441/html5/thumbnails/14.jpg)
14Results
IMU failure: Experimental Scenario
VDM parameters calibration:• On a separate flight:• Start with nominal values in
simulations• IMU and cm-level GNSS data fused• Navigation states as observations• VDM parameters estimated
MEMS IMUStandalone GNSS
![Page 15: VDM-based Navigation for Small UAVs · • As old as GPS (>30 years) • On most UAVs today (outdoor) 3. Introduction. Integrated Inertial and Satellite Navigation (INS -GNSS) INS:](https://reader034.vdocument.in/reader034/viewer/2022050223/5f687a7a90e3a7222c249441/html5/thumbnails/15.jpg)
15Results
IMU failure: Experimental Scenario
The main suspect: Residual error in VDM parameters estimationSolution: Absolute attitude reference via photogrammetry (TBD)
![Page 16: VDM-based Navigation for Small UAVs · • As old as GPS (>30 years) • On most UAVs today (outdoor) 3. Introduction. Integrated Inertial and Satellite Navigation (INS -GNSS) INS:](https://reader034.vdocument.in/reader034/viewer/2022050223/5f687a7a90e3a7222c249441/html5/thumbnails/16.jpg)
Realization matters!• Estimation architecture,
VDM/IMU priors & on-linere-fining
• Platform, actuators, IMU + mount + models, time-stamping
GNSS outage, 2.2 kg fixed-wing MAV• Emulation: up to 100x better
without additional sensor • Experiment: 20-40x better
(e.g., @3min: 50 m vs 2 km)
Attitude estimation• Emulation:
<1° for roll & pitch, <2° for yaw• Experiment:
Mean ~5°, Max ~20-40° => Need to improve VDM calibration
Outlook• Attitude reference from
photogrammetry• Redundant IMUs• Direct actuation measurements• Online implementation
16Conclusion
Conclusion & Outlook
Acknowledgements: DDPS – CTI (Innosuisse)
![Page 17: VDM-based Navigation for Small UAVs · • As old as GPS (>30 years) • On most UAVs today (outdoor) 3. Introduction. Integrated Inertial and Satellite Navigation (INS -GNSS) INS:](https://reader034.vdocument.in/reader034/viewer/2022050223/5f687a7a90e3a7222c249441/html5/thumbnails/17.jpg)
17Publications
Selected Publications
Thank you for your attention• Concept / Monte-Carlo simulation
[Navigation, 2016] Autonomous Vehicle Dynamic Model-Based Navigation for Small UAVs
• Enhanced modeling / Experiments[Robotics and Autonomous Systems, 2018] Assessment of VDM-based Autonomous Navigation of a UAV under Operational Conditions
• Mapping[ISPRS Archives, 2016] Application of Vehicle Dynamic Modeling in UAVs for Precise Determination of Exterior Orientation
• Wind effects[ION GNSS+, 2016] Evaluation of Wind Effects on UAV Autonomous Navigation Based on Vehicle Dynamic Model
• Sensitivity Analysis[IEEE Transactions TAES, 2018 (under review)] Global Sensitivity Analysis ofVDM-based Navigation for UAVs