Background Point Filtering of Low-Channel Infrastructure-Based LiDAR Data Using a Slice-Based Projection Filtering Algorithm
Abstract
:1. Introduction
- (1)
- A 3-D point cloud is projected into 2-D polar coordinate points, and a slice-based projection filtering algorithm is proposed to reduce the point cloud data processing dimensions and computing time.
- (2)
- The point cloud is classified into four categories in a slice unit: Valuable object points (VOPs), worthless object points (WOPs), abnormal ground points (AGPs), and normal ground points (NGPs). Based on the point cloud classification results, the traffic objects and their surrounding information would be easily identified from an individual frame of point cloud.
- (3)
- A machine learning model based on a backpropagation artificial neural network (BP-ANN) is used to dynamically fit the road gradient or employing the inclination of the LiDAR sensor, as to improve the adaptability of the algorithm in a complex environment.
2. LiDAR Sensor and Points Classification
3. Definitions and Assumptions
3.1. Definition of Slice
3.2. Definition of Abnormal and Normal Ground Points
3.3. Definition of Valuable and Worthless Object Points
4. Slice-Based Projection Filtering Algorithm
4.1. Projection
4.2. Valid Slices Extraction
Algorithm 1 Extracting Valid Slices |
|
4.3. Abnormal and Normal Ground Points Separation
4.3.1. Ground Point Extraction
4.3.2. Separation Method
4.3.3. Separation Results
4.4. Valuable and Worthless Object Points Separation
4.4.1. Key Region Optimization
4.4.2. Valuable Object Points Extraction
5. Experiments and Validation Analysis
5.1. Filtering Results
5.2. Runtime
6. Conclusions and Discussion
- (1)
- Projecting 3 = D point cloud into 2-D polar coordinates can reduce the computation complexity and memory resource in the point cloud loop processing during the background point filtering. The processing time using 2-D polar coordinates is about one quarter of the processing time using the 3-D point cloud directly.
- (2)
- Using the vertical slice unit, which is different from the horizontal slice unit mentioned in the the state-of-the-art literature, can effectively classify the point cloud into VOPs, WOPs, AGPs, and NGPs. It can further remove the worthless points in the background point filtering. The accurate and excluding efficiency is about 5 times that is not based on the vertical slice unit.
- (3)
- In practical applications, road pavement conditions and LiDAR installation statuses need to be considered, such as the road gradient and LiDAR sensor inclination. Therefore, a BP-ANN machine learning model was proposed to fit the inclination angle between the BGP and the projection plane to improve the flexibility of the background point algorithm in a complex environment.
Author Contributions
Funding
Conflicts of Interest
References
- Caltagirone, L.; Bellone, M.; Svensson, L.; Wahde, M. LIDAR–camera fusion for road detection using fully convolutional neural networks. Robot. Auton. Syst. 2019, 111, 125–131. [Google Scholar] [CrossRef] [Green Version]
- Hecht, J. Lidar for self-driving cars. Opt. Photonics News 2018, 29, 26–33. [Google Scholar] [CrossRef]
- Javanmardi, E.; Gu, Y.; Javanmardi, M.; Kamijo, S. Autonomous vehicle self-localization based on abstract map and multi-channel LiDAR in urban area. IATSS Res. 2019, 43, 1–13. [Google Scholar] [CrossRef]
- Wang, H.; Wang, B.; Liu, B.; Meng, X.; Yang, G. Pedestrian recognition and tracking using 3D LiDAR for autonomous vehicle. Robot. Auton. Syst. 2017, 88, 71–78. [Google Scholar] [CrossRef]
- Griggs, T.; Wakabayashi, D. How a self-driving Uber killed a Pedestrian in Arizona. New York Times, 19 March 2018. [Google Scholar]
- Vlasic, B.; Boudette, N.E. Self-Driving Tesla Was Involved in Fatal Crash, US Says. New York Times, 30 June 2016. [Google Scholar]
- Wang, Y.; Lu, G.; Yu, H. Traffic Engineering Considering Cooperative Vehicle Infrastructure System. Strateg. Study Chin. Acad. Eng. 2018, 20, 106–110. [Google Scholar] [CrossRef]
- Redmon, J.; Farhadi, A. YOLO9000: Better, faster, stronger. In Proceedings of the IEEE Conference on Computer Vision and Pattern Recognition, Honolulu, HI, USA, 21–26 July 2017; pp. 7263–7271. [Google Scholar]
- You, X.; Zheng, Y. An accurate and practical calibration method for roadside camera using two vanishing points. Neurocomputing 2016, 204, 222–230. [Google Scholar] [CrossRef]
- Mohamed, Y.S.; Shehata, H.M.; Abdellatif, M.; Awad, T.H. Steel crack depth estimation based on 2D images using artificial neural networks. Alex. Eng. J. 2019, 58, 1167–1174. [Google Scholar] [CrossRef]
- Zhao, J. Exploring the Fundamentals of Using Infrastructure-Based LiDAR Sensors to Develop Connected Intersections. Ph.D. Thesis, Texas Tech University, Lubbock, TX, USA, 2019. [Google Scholar]
- Lee, J.-S.; Jo, J.-H.; Park, T.-H. Segmentation of Vehicles and Roads by a Low-Channel Lidar. IEEE Trans. Intell. Transp. Syst. 2019, 20, 4251–4256. [Google Scholar] [CrossRef]
- Kwon, J.-S.; Kim, D.-S.; Hwang, T.-H.; Park, H.-M. A Development of Effective Object Detection System Using Multi-Device LiDAR Sensor in Vehicle Driving Environment. J. Korea Inst. Electron. Commun. Sci. 2018, 13, 313–320. [Google Scholar]
- Zhao, J.; Xu, H.; Liu, H.; Wu, J.; Zheng, Y.; Wu, D. Detection and tracking of pedestrians and vehicles using roadside LiDAR sensors. Transp. Res. Part C Emerg. Technol. 2019, 100, 68–87. [Google Scholar] [CrossRef]
- Azim, A.; Aycard, O. Detection, classification and tracking of moving objects in a 3D environment. In Proceedings of the 2012 IEEE Intelligent Vehicles Symposium (IV 2012), Alcal de Henares, Madrid, Spain, 3–7 June 2012; pp. 802–807. [Google Scholar]
- Asvadi, A.; Premebida, C.; Peixoto, P.; Nunes, U. 3D Lidar-based static and moving obstacle detection in driving environments: An approach based on voxels and multi-region ground planes. Robot. Auton. Syst. 2016, 83, 299–311. [Google Scholar] [CrossRef]
- Dewan, A.; Caselitz, T.; Tipaldi, G.D.; Burgard, W. Motion-based detection and tracking in 3d lidar scans. In Proceedings of the 2016 IEEE International Conference on Robotics and Automation (ICRA), Stockholm, Sweden, 16–21 May 2016; pp. 4508–4513. [Google Scholar]
- Zhang, Y.; Wang, J.; Wang, X.; Dolan, J.M. Road-segmentation-based curb detection method for self-driving via a 3D-LiDAR sensor. IEEE Trans. Intell. Transp. Syst. 2018, 19, 3981–3991. [Google Scholar] [CrossRef]
- Li, Q.; Chen, L.; Li, M.; Shaw, S.-L.; Nüchter, A.J. A sensor-fusion drivable-region and lane-detection system for autonomous vehicle navigation in challenging road scenarios. IEEE Trans. Veh. Technol. 2013, 63, 540–555. [Google Scholar] [CrossRef]
- Cao, M.; Wang, J.J. Obstacle Detection for Autonomous Driving Vehicles with Multi-LiDAR Sensor Fusion. J. Dyn. Syst. Meas. Control 2020, 142, 021007. [Google Scholar] [CrossRef]
- Wu, J.; Tian, Y.; Xu, H.; Yue, R.; Wang, A.; Song, X. Automatic ground points filtering of roadside LiDAR data using a channel-based filtering algorithm. Opt. Laser Technol. 2019, 115, 374–383. [Google Scholar] [CrossRef]
- Vosselman, G.; Dijkman, S. 3D building model reconstruction from point clouds and ground plans. Int. Arch. Photogramm. Remote Sens. Spat. Inf. Sci. 2001, 34, 37–44. [Google Scholar]
- Konolige, K.; Agrawal, M.; Blas, M.R.; Bolles, R.C.; Gerkey, B.; Sola, J.; Sundaresan, A. Mapping, navigation, and learning for off-road traversal. J. Field Robot. 2009, 26, 88–113. [Google Scholar] [CrossRef] [Green Version]
- Zhang, K.; Whitman, D.; Sensing, R. Comparison of three algorithms for filtering airborne lidar data. Photogramm. Eng. 2005, 71, 313–324. [Google Scholar] [CrossRef] [Green Version]
- Wu, J.; Xu, H.; Sun, Y.; Zheng, J.; Yue, R. Automatic background filtering method for roadside LiDAR data. Transp. Res. Rec. 2018, 2672, 106–114. [Google Scholar] [CrossRef]
- Börcs, A.; Nagy, B.; Benedek, C.J.I.G.; Letters, R.S. Instant object detection in lidar point clouds. IEEE Geosci. Remote Sens. Lett. 2017, 14, 992–996. [Google Scholar] [CrossRef] [Green Version]
- Halterman, R.; Bruch, M. Velodyne HDL-64E lidar for unmanned surface vehicle obstacle detection. In Proceedings of the Unmanned Systems Technology XII, Orlando, FL, USA, 6–9 April 2010; p. 76920D. [Google Scholar]
- Minemura, K.; Liau, H.; Monrroy, A.; Kato, S. LMNet: Real-time Multiclass Object Detection on CPU Using 3D LiDAR. In Proceedings of the 2018 3rd Asia-Pacific Conference on Intelligent Robot Systems (ACIRS), Singapore, 21–23 July 2018; pp. 28–34. [Google Scholar]
- Velodyne. VLP-16 User’s Manual and Programming Guide; Velodyne LiDAR: San Jose, CA, USA, 2016. [Google Scholar]
- Velodyne. VLP-16 User Manual; Velodyne LiDAR: San Jose, CA, USA, 2018. [Google Scholar]
- Hochreiter, S.; Schmidhuber, J. Long short-term memory. Neural Comput. 1997, 9, 1735–1780. [Google Scholar] [CrossRef] [PubMed]
- Hoerl, A.E.; Kennard, R.W.J.T. Ridge regression: Biased estimation for nonorthogonal problems. Technometrics 1970, 12, 55–67. [Google Scholar] [CrossRef]
- Drucker, H.; Burges, C.J.; Kaufman, L.; Smola, A.J.; Vapnik, V. Support vector regression machines. In Proceedings of the 9th International Conference on Advances in Neural Information Processing Systems; MIT Press: Cambridge, MA, USA, 1997; pp. 155–161. [Google Scholar]
- General Administration of Sport of China. National Constitution Monitoring Bulletin. Available online: http://www.sport.gov.cn/index.html (accessed on 20 March 2020).
- Ester, M.; Kriegel, H.-P.; Sander, J.; Xu, X. A density-based algorithm for discovering clusters in large spatial databases with noise. Kdd 1996, 96, 226–231. [Google Scholar]
- MacQueen, J. Some methods for classification and analysis of multivariate observations. In Proceedings of the Fifth Berkeley Symposium on Mathematical Statistics and Probability; University of California: Berkeley, CA, USA, 1967; pp. 281–297. [Google Scholar]
Fitting the Inclination Angle | The Key Region | Total | |
---|---|---|---|
Left Side | Right Side | ||
Without fitting | 1939 | 1453 | 3392 |
With fitting | 3054 | 1422 | 4476 |
Point Cloud | Algorithms | Before Filtering | After Filtering | Filtering Percentage (%) |
---|---|---|---|---|
raw point cloud | RANSAC | 28960 | 24347 | 15.9 |
3-D-DSF | 28960 | 956 | 96.7 | |
SPF | 28960 | 5738 | 80.1 | |
VOPs | RANSAC | 5596 | 4943 | 11.7 |
3-D-DSF | 5596 | 867 | 84.5 | |
SPF | 5596 | 4476 | 20.0 | |
AGPs | RANSAC | 1482 | 1378 | 7.0 |
3-D-DSF | 1482 | 48 | 96.8 | |
SPF | 1482 | 1262 | 14.8 | |
VOPs + AGPs | RANSAC | 24347 | 6321 | 74.0 |
3-D-DSF | 956 | 915 | 4.29 | |
SPF | 5738 | 5738 | 0.00 |
Algorithm | Runtime (ms) | Frame Needed in the Algorithm |
---|---|---|
RANSAC | 198 | single-frame |
3-D-DSF | 113 | multi-frames |
SPF | 51 | single-frame |
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Lin, C.; Liu, H.; Wu, D.; Gong, B. Background Point Filtering of Low-Channel Infrastructure-Based LiDAR Data Using a Slice-Based Projection Filtering Algorithm. Sensors 2020, 20, 3054. https://doi.org/10.3390/s20113054
Lin C, Liu H, Wu D, Gong B. Background Point Filtering of Low-Channel Infrastructure-Based LiDAR Data Using a Slice-Based Projection Filtering Algorithm. Sensors. 2020; 20(11):3054. https://doi.org/10.3390/s20113054
Chicago/Turabian StyleLin, Ciyun, Hui Liu, Dayong Wu, and Bowen Gong. 2020. "Background Point Filtering of Low-Channel Infrastructure-Based LiDAR Data Using a Slice-Based Projection Filtering Algorithm" Sensors 20, no. 11: 3054. https://doi.org/10.3390/s20113054
APA StyleLin, C., Liu, H., Wu, D., & Gong, B. (2020). Background Point Filtering of Low-Channel Infrastructure-Based LiDAR Data Using a Slice-Based Projection Filtering Algorithm. Sensors, 20(11), 3054. https://doi.org/10.3390/s20113054