position and attitude determination using digital image processing
DESCRIPTION
Position and Attitude Determination using Digital Image Processing. A UROP sponsored research project. Sean VandenAvond. Mentors: Brian Taylor, Dr. Demoz Gebre-Egziabher. Overview. Motivation Introduction Feature Matching Position Determination Google Earth Navigation Simulation - PowerPoint PPT PresentationTRANSCRIPT
![Page 1: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/1.jpg)
Position and Attitude Determination using Digital
Image Processing
Sean VandenAvond
Mentors: Brian Taylor, Dr. Demoz Gebre-Egziabher
A UROP sponsored research project
![Page 2: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/2.jpg)
Overview
• Motivation• Introduction• Feature Matching• Position Determination• Google Earth Navigation Simulation• Future Work
![Page 3: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/3.jpg)
Inertial Measurement Units• Measure linear
accelerations and rotational velocities
• May contain bias error• Error grows over time• $1,000 – $100,000
![Page 4: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/4.jpg)
GPS Update
IMU Readings
IntegrateAttitude andPosition
GPS Update
Error or Noise
• IMU frequency: 50-200 hz• GPS frequency: 1 hz
![Page 5: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/5.jpg)
Problems with GPS• GPS failure can occur in small UAVs
- Interference- Jamming- Spoofing
• University of Texas successfully spoofed an UAV GPS (2012) and an 80 million dollar yacht (2013).
• RQ-170 Sentinel speculated to be spoofed and captured by Iranians (2011)
• Severely limits autonomy and control without backup system.
![Page 6: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/6.jpg)
Motivation• Small UAVs are limited by:
– Price– Weight
• A backup system is required to increase the reliability. This system should be:– Inexpensive– Lightweight– Self-enclosed– Robust and practical
![Page 7: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/7.jpg)
GPS
Images
Position Update
Processing
![Page 8: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/8.jpg)
Proof of ConceptMATLAB
– OpenSURF– Algorithms
Google Earth– KML filesFeature
Matching
Navigation
Algorithms
Simulation
![Page 9: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/9.jpg)
Feature Matching• Feature: unique grouping of pixels in an image.• Given two images the program will output best
estimates on matching features.• Limitations:
- shadows/lighting- lack of unique image data- minimal relative image rotation
These limitations can lead to mismatched feature points between images error in position estimations.
![Page 10: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/10.jpg)
Feature Matching
OpenSURF
![Page 11: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/11.jpg)
Limitations
Shadows and lighting can degrade image matching.
![Page 12: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/12.jpg)
Limitations
No good feature points
![Page 13: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/13.jpg)
Limitations
Pitch = 40º Heading = 40º
![Page 14: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/14.jpg)
Position and Attitude Determination
• PnP problem• Uses known landmark
positions – At least 3 landmarks
• Various PnP algorithms available. – Direct Linear Transform– EPnP– Constrained Least
Square positions.
![Page 15: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/15.jpg)
Depth Ambiguity• Information lost when
converting from 3D scene to 2D image.
• Need to know landmark coordinates in all three dimensions.
• Non unique solution if you don’t have 3rd dimension
• Algorithms breaks down when viewing 2D scene
![Page 16: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/16.jpg)
Limitations
![Page 17: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/17.jpg)
Limitations
![Page 18: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/18.jpg)
Simpler Solution• Let Heading = Pitch = Roll = 0º
![Page 19: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/19.jpg)
Position Determination
Use image matching and FOV calculations to determine new position.
![Page 20: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/20.jpg)
Resulting Position
![Page 21: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/21.jpg)
Attitude Error
• Pitch of 5 degrees: estimated position error of
![Page 22: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/22.jpg)
Simulation• Full guidance and navigation simulation
in Google Earth using MATLAB• Assumptions:
- Heading = Pitch = Roll = 0- Neglecting aircraft dynamics- Fixed velocity- Fixed altitude
![Page 23: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/23.jpg)
Initial image at known lat/lon
Destination
New heading
“AircraftSimulation”
New image
Feature matching
Estimate new lat/lon
Old image
![Page 24: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/24.jpg)
Results
![Page 25: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/25.jpg)
Matched Images
![Page 26: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/26.jpg)
Mismatch Error
![Page 27: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/27.jpg)
Percent Overlap
Image 1 Image 2Overlap
More Overlap:- Better matches- Slower
Tests done with 3000 foot length step overlap of about 25 percent
![Page 28: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/28.jpg)
Summary• Over 100 miles in simulation.• Show promise for using digital image processing for a
backup navigation system.• Benefits
- Lightweight- Inexpensive- Self-enclosed
• Limitations- Needs unique feature points- Computationally expensive
![Page 29: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/29.jpg)
Future Work
• Couple simulation with UAV lab MATLAB script to include errors in sensors.
• Post-processing from UAV lab flight tests• Adapt to allow onboard flight testing
![Page 30: Position and Attitude Determination using Digital Image Processing](https://reader033.vdocuments.mx/reader033/viewer/2022061606/56816625550346895dd97f9a/html5/thumbnails/30.jpg)
Results