Fig. 1. An example image with a few support lines in order to discuss usefulness of parallel lines in our life.
Fig. 2. Various pallet images with two or three edge lines that are useful for estimating orientation of each pallet.
Fig. 3. Perspective projection in a XYZ-camera coor-dinate system onto a xy-image coordinate sys-tem.
Fig. 4. Core idea of estimating three-dimensional di-rection of parallel lines. Cross product of two normal vectors for the upper plane and the low-er plane indicates their 3D direction.
Fig. 5. Diagram to show an estimation method of three-dimensional parallel line direction based on four selected points.
Fig. 6. An approach to determination of pallet orientation in [6]. (a) relation diagram between the (yellow) front plane of a pallet and its back-projection onto a virtual plane with various orientation, (b) a case of aligning the virtual plane parallel to the front plane of pallet.
Fig. 7. Sample images of pallet with various orientation and distance to test usefulness of the proposed method.
Table 1. Experimental results for four pallets with various distance and orientation
Table 2. Execution times for measuring orientation and location of pallets
References
- G. Garibotto, S. Masciangelo, M. Ilic, and P. Bassino, "ROBOLIFT: A Vision Guided Autonomous Fork-lift for Pallet Handling," Proceedings of IEEE/RSJ International Conference on Intelligent Robots and Systems, pp. 656-663, 1996.
- J. Pages, X. Armangue, J. Salvi, J. Freixenet, and J. Marti, "A Computer Vision System for Autonomous Forklift Vehicles in Industrial Environments," Proceedings of 9th Mediterranean Conference on Control and Automation, pp. 1-6, 2001.
- D. Lecking, O. Wulf, and B. Wagner, "Variable Pallet Pick-Up for Automatic Guided Vehicles in Industrial Environments," Proceedings of IEEE Conference on Emerging Technologies and Factory Automation, pp. 1169-1174, 2006.
- M. Seelinger and J.D. Yoder, "Automatic Visual Guidance of a Forklift Engaging a Pallet," Robotics and Autonomous Systems, Vol. 54, Issue 12, pp. 1026-1038, 2006. https://doi.org/10.1016/j.robot.2005.10.009
- S. Byun and M. Kim, "Real-Time Positioning and Orienting of Pallets Based on Monocular Vision," Proceedings of IEEE International Conference on Tools with Artificial Intelligence (ICTAI), pp. 505-508, 2008.
- S. Byun and M. Kim, "Pallet Measurement Method for Automatic Pallet Engaging in Real-Time," Journal of Korea Multimedia Society, Vol. 14, No. 2, pp. 171-181, 2011. https://doi.org/10.9717/kmms.2011.14.2.171
- M.R. Walter, S. Karaman, E. Frazzoli, and S. Teller, "Closed-Loop Pallet Engagement in an Unstructured Environment," Proceedings of IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), pp. 5119-5126, 2010.
- D. Haanpaa, G. Beach, and C.J. Cohen, "Machine Vision Algorithms for Robust Pallet Engagement and Stacking," Proceedings of IEEE Applied Imagery Pattern Recognition Workshop (AIPR), pp. 1-8, 2016.
- J. Xiao, H. Lu, L. Zhang, and J. Zhang, "Pallet Recognition and Localization Using an RGB-D Camera," International Journal of Advanced Robotic Systems, Vol. 14, Issue 6, 2017.
- L. Baglivo, N. Biasi, F. Biral, N. Bellomo, E. Bertolazzi, M.D. Lio, et al., "Autonomous Pallet Localization and Picking for Industrial Forklifts: A Robust Range and Look Method," Measurement Science and Technology, Vol. 22, No. 8, 2011.
- R. Jain, R. Kasturi, and B.G. Schunck, Machine Vision, McGraw-Hill, New York, 1995.
- Z. Zhang, A Flexible New Technique for Camera Calibration, Technical Report MSR-TR-98-71, 1998.
- R. Hartley and A. Zisserman, Multiview Geometry in Computer Vision, Cambridge University Press, Cambridge, 2003.
- Flat Pallets for Through Transit (KS T 1372), http://standard.go.kr/KSCI/standardIntro/getStandardSearchView.do (accessed Sep., 13, 2018).
- A.J. Davison, I.D. Reid, N.D. Molton, and O. Stasse, “MonoSLAM: Real-Time Single Camera SLAM,” IEEE Transactions on Pattern Analysis and Machine Intelligence, Vol. 29, No. 6, pp. 1052-1067, 2007. https://doi.org/10.1109/TPAMI.2007.1049
- W. Hu, T. Tan, L. Wang, and S. Maybank, “A Survey on Visual Surveillance of Object Motion and Behaviors,” IEEE Transaction on System, Man and Cybernetics, Part C: Applications and Reviews, Vol. 34, No. 3, pp. 334-352, 2004. https://doi.org/10.1109/TSMCC.2004.829274