“…Recently, learning-based odometry methods have shown impressive accuracy on datasets compared with conventional methods based on hand-crafted features. It is found that learning-based methods can deal with sparse features and dynamic environments [1], [2], which are usually difficult for conventional methods. To our knowledge, most learning-based methods are on the 2D visual odometry [3], [4], [5], [6], [7], [8], [9] or utilize 2D convolution on the projected information of LiDAR [10], [11], [12], [13], [14].…”