1. Research Centre for Intelligent Transportation, Zhejiang Lab, Hangzhou 311121, China
2. Institute of Intelligent Vehicle, School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China
3. Intelligent Vehicles & Cognitive Robotics, Technische Universiteit Delft, 2600 AA Delft, The Netherlands
4. Faculty of Engineering and Information Science, University of Wollongong, Wollongong 2522, Australia