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Estimating the Driving State of Oncoming Vehicles From a Moving Platform Using Stereo Vision IEEE Intelligent Transportation Systems 2009. Alexander Barth and Uwe Franke. M.S. Student, Heejong Hong 07. 14. 2014. Outline. Introduction Related Works Proposed Method Experimental Results
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Estimating the Driving State of Oncoming Vehicles From a Moving Platform Using Stereo VisionIEEE Intelligent Transportation Systems 2009 Alexander Barth and Uwe Franke M.S. Student, Heejong Hong 07. 14. 2014
Outline • Introduction • RelatedWorks • Proposed Method • ExperimentalResults • Conclusion
Introduction • Driver-assistance and safety systems Dynamic Object Detection for DAS Safety System with Dynamic Path Estimation http://www.6d-vision.com/home/bedeutung
Related Works • A model-free object representation based on groups • Fusion active sensors • Track-before-detection • Rediscovering an image region labeled as vehicle D. Beymer , P. McLauchlan , B. Coifman and J. Malik "A real-time computer vision system for measuring traffic parameters", Proc. Comput. Vis. Pattern Recog, pp.495 -501 1997 M. Maehlisch , W. Ritter and K. Dietmayer "De-cluttering with integrated probabilistic data association for multisensormultitarget ACC vehicle tracking", Proc. IEEE Intell. Veh. Symp., pp.178 -183 2007 U. Franke , C. Rabe , H. Badino and S. Gehrig "6D-vision: Fusion of stereo and motion for robust environment perception", Proc. 27th DAGM Symp., pp.216 -223 2005 X. Li , X. Yao , Y. Murphey , R. Karlsen and G. Gerhart "A real-time vehicle detection and tracking system in outdoor traffic scenes", Proc. 17th Int. Conf. Pattern Recog., pp.II:761 -II:764 2004 1. 2. 3.
Object Model • Pose (relative orientation and translation to ego-vehicle) • Motion State (velocity, acceleration, yaw rate) • Shape (rigid 3-D point cloud) Pose Motion State Shape
Object Tracking • Extended Kalman Filter (EKF): Kalman filter for nonlinear model Example) State transition(f) and observation model(h) Discrete-time predict and update equations Jacobian of system & measurement model Wikipedia : http://en.wikipedia.org/wiki/Extended_Kalman_filter
Object Tracking 1. State Vector of an object instance Reference point in ego-coordinates Rotation point in object-coordinates The object origin is ideally defined on the center rear axis
Object Tracking 2. Dynamic(System) Model Predicted state vector Time-discrete system Equation Transformation of an object point Translation matrix Ris 3x3 rotation matrix around the height axis N. Kaempchen , K. Weiss , M. Schaefer and K. Dietmayer "IMM object tracking for high dynamic driving maneuvers", Proc. IEEE Intell. Veh. Symp., pp.825 -830 2004
Object Tracking 3. Measurement Model Objects feature points on image coordinates using feature tracker (KLT) Feature point tracking using KLT The measurement nonlinear eq. : perspective camera model Jacobian of measurement model
Kalman Filter Initialization • Image Based Initialization • Radar-Based Initialization(detect oncoming vehicle up to 200m) The centroid of the 3-D positions : The mean velocity vector : Initial Yaw : The lateral and longitudinal positions of the radar target : , Absolute radar velocity of the object : Initial Yaw :
Point Model Update t • Maximum-likelihood estimation • Simple average filter Object’s Shape Expectation = 3x3 covariance matrix of Expected object’s shape
Simulation Results • Synthetic Sequence
Real World Results • Country Road Curve I
Real World Results • Country Road Curve II
Real World Results • Oncoming Traffic at Intersections
Real World Results • Leading Vehicles & Partial Occlusions
Real World Results • Challenges and Limits
Joint Histogram Based Cost Aggregation for Stereo Matching - TPAMI 2013 Conclusion
Joint Histogram Based Cost Aggregation for Stereo Matching - TPAMI 2013 Conclusion • Contribution • New method for the image-based real-time tracking (25Hz, 640x480) • Results of experiments with synthetic data & real-world • Two different object detection method (image & radar) • Feature-based object point model does not require a priori knowledge about the object’s shape • Weakness • No specific system block diagram • User defined rotation point • Shape depends on outlier removing algorithm (ex : max distance parameter) • Shape is very sensitive about outlier of point cloud(because of yaw)