An Image-Based Real-Time Georeferencing Scheme for a UAV Based on a New Angular Parametrization
Simultaneous localization and mapping (SLAM) of a monocular projective camera installed on an unmanned aerial vehicle (UAV) is a challenging task in photogrammetry, computer vision, and robotics. This paper presents a novel real-time monocular SLAM solution for UAV applications. It is based on two s...
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| Format: | Article |
| Language: | English |
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MDPI AG
2020-09-01
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| Series: | Remote Sensing |
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| Online Access: | https://www.mdpi.com/2072-4292/12/19/3185 |
| _version_ | 1827705149432266752 |
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| author | Ehsan Khoramshahi Raquel A. Oliveira Niko Koivumäki Eija Honkavaara |
| author_facet | Ehsan Khoramshahi Raquel A. Oliveira Niko Koivumäki Eija Honkavaara |
| author_sort | Ehsan Khoramshahi |
| collection | DOAJ |
| description | Simultaneous localization and mapping (SLAM) of a monocular projective camera installed on an unmanned aerial vehicle (UAV) is a challenging task in photogrammetry, computer vision, and robotics. This paper presents a novel real-time monocular SLAM solution for UAV applications. It is based on two steps: consecutive construction of the UAV path, and adjacent strip connection. Consecutive construction rapidly estimates the UAV path by sequentially connecting incoming images to a network of connected images. A multilevel pyramid matching is proposed for this step that contains a sub-window matching using high-resolution images. The sub-window matching increases the frequency of tie points by propagating locations of matched sub-windows that leads to a list of high-frequency tie points while keeping the execution time relatively low. A sparse bundle block adjustment (BBA) is employed to optimize the initial path by considering nuisance parameters. System calibration parameters with respect to global navigation satellite system (GNSS) and inertial navigation system (INS) are optionally considered in the BBA model for direct georeferencing. Ground control points and checkpoints are optionally included in the model for georeferencing and quality control. Adjacent strip connection is enabled by an overlap analysis to further improve connectivity of local networks. A novel angular parametrization based on spherical rotation coordinate system is presented to address the gimbal lock singularity of BBA. Our results suggest that the proposed scheme is a precise real-time monocular SLAM solution for a UAV. |
| first_indexed | 2024-03-10T15:57:11Z |
| format | Article |
| id | doaj.art-c4f2e281829c456c926b076b68120df7 |
| institution | Directory Open Access Journal |
| issn | 2072-4292 |
| language | English |
| last_indexed | 2024-03-10T15:57:11Z |
| publishDate | 2020-09-01 |
| publisher | MDPI AG |
| record_format | Article |
| series | Remote Sensing |
| spelling | doaj.art-c4f2e281829c456c926b076b68120df72023-11-20T15:34:32ZengMDPI AGRemote Sensing2072-42922020-09-011219318510.3390/rs12193185An Image-Based Real-Time Georeferencing Scheme for a UAV Based on a New Angular ParametrizationEhsan Khoramshahi0Raquel A. Oliveira1Niko Koivumäki2Eija Honkavaara3Department of Remote Sensing and Photogrammetry of the Finnish Geospatial Research Institute FGI, Geodeetinrinne 2, FI-02430 Masala, FinlandDepartment of Remote Sensing and Photogrammetry of the Finnish Geospatial Research Institute FGI, Geodeetinrinne 2, FI-02430 Masala, FinlandDepartment of Remote Sensing and Photogrammetry of the Finnish Geospatial Research Institute FGI, Geodeetinrinne 2, FI-02430 Masala, FinlandDepartment of Remote Sensing and Photogrammetry of the Finnish Geospatial Research Institute FGI, Geodeetinrinne 2, FI-02430 Masala, FinlandSimultaneous localization and mapping (SLAM) of a monocular projective camera installed on an unmanned aerial vehicle (UAV) is a challenging task in photogrammetry, computer vision, and robotics. This paper presents a novel real-time monocular SLAM solution for UAV applications. It is based on two steps: consecutive construction of the UAV path, and adjacent strip connection. Consecutive construction rapidly estimates the UAV path by sequentially connecting incoming images to a network of connected images. A multilevel pyramid matching is proposed for this step that contains a sub-window matching using high-resolution images. The sub-window matching increases the frequency of tie points by propagating locations of matched sub-windows that leads to a list of high-frequency tie points while keeping the execution time relatively low. A sparse bundle block adjustment (BBA) is employed to optimize the initial path by considering nuisance parameters. System calibration parameters with respect to global navigation satellite system (GNSS) and inertial navigation system (INS) are optionally considered in the BBA model for direct georeferencing. Ground control points and checkpoints are optionally included in the model for georeferencing and quality control. Adjacent strip connection is enabled by an overlap analysis to further improve connectivity of local networks. A novel angular parametrization based on spherical rotation coordinate system is presented to address the gimbal lock singularity of BBA. Our results suggest that the proposed scheme is a precise real-time monocular SLAM solution for a UAV.https://www.mdpi.com/2072-4292/12/19/3185photogrammetryreal-time monocular SLAMUAVtrajectory estimationGNSSIMU |
| spellingShingle | Ehsan Khoramshahi Raquel A. Oliveira Niko Koivumäki Eija Honkavaara An Image-Based Real-Time Georeferencing Scheme for a UAV Based on a New Angular Parametrization Remote Sensing photogrammetry real-time monocular SLAM UAV trajectory estimation GNSS IMU |
| title | An Image-Based Real-Time Georeferencing Scheme for a UAV Based on a New Angular Parametrization |
| title_full | An Image-Based Real-Time Georeferencing Scheme for a UAV Based on a New Angular Parametrization |
| title_fullStr | An Image-Based Real-Time Georeferencing Scheme for a UAV Based on a New Angular Parametrization |
| title_full_unstemmed | An Image-Based Real-Time Georeferencing Scheme for a UAV Based on a New Angular Parametrization |
| title_short | An Image-Based Real-Time Georeferencing Scheme for a UAV Based on a New Angular Parametrization |
| title_sort | image based real time georeferencing scheme for a uav based on a new angular parametrization |
| topic | photogrammetry real-time monocular SLAM UAV trajectory estimation GNSS IMU |
| url | https://www.mdpi.com/2072-4292/12/19/3185 |
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