1. SLAM论文
1.1 SOFT-SLAM:Computationally efficient stereo visual simultaneous localization and mapping for autonomous unmanned aerial vehicles(KITTI 双目第一名)
1.2 [CVPR2018]CodeSLAM-Learning a Compact, Optimisable Representation for Dense Visual SLAM
1.2.1 Contributions:
l The derivation of a compact and optimisable representation of dense geometry by conditioning a depth auto encoder on intensity images (深度编码来表达稠密几何结构)
l The implementation of the first real-time targeted
monocular system that achieves such a tight joint optimisation of motion and dense geometry.
1.2.2 depth auto encoder result:
1.2.3 Illustration of the SfM system
1.2.4 总结
在后端优化的时候,将光度差和重投影误差一起优化,数据关联使用文中的共视depth auto encoder
1.3 [CVPR2018]ICE-BA: Incremental, Consistent and Efficient Bundle Adjustment for Visual-Inertial SLAM
1.3.1 Contributions:
l a new sliding window based solver that leverages the incremental nature of SLAM measurements to achieve more than 10x efficiency compared to the state-of-the-arts
l a new relative marginalization algorithm that resolves the conflicts between sliding window marginalization bias and global loop closure constraints
1.3.2 Optimization framework
1.3.3 Relative Marginalization
1.3.4 总结
本篇文章在local BA的过程中,选定新的reference keyframe,后面的相机位姿将相对于该帧做优化,这和HoloLens里面选定锚点位置有相似之处。
1.4 [CVPR2018] Learning to Find Good Correspondences
1.4.1 Contributions
l being keypoint-based, it generalizes better than image-based dense methods to unseen scenes, which we demonstrate with a single model that outperforms current methods on drastically different indoors and outdoors datasets
l it requires only weak supervision through essential matrices for training
l it can work effectively with very little training data
1.4.2 Result
1.4.3 Network
1.4.4 总结
提取局部特征点之后,匹配完扔给神经网络,它能够划分出inlier和outlier,这是一个分类器。
1.5 [CVPR2017]CNN-SLAM: Real-time dense monocular SLAM with learned depth prediction
1.5.1 Contributions
l we illustrate the proposed frameworkfor 3D reconstruction, where CNN-predicted dense depth maps are fused together with depth measurements obtained from direct monocular SLAM
l we show how CNN-predicted semantic segmentation can also be coherently fused with the global reconstruction model
1.5.2 overview
1.5.3 总结
使用CNN估计单幅视图的深度,并进行语义上的分割,后端优化还是传统的SLAM优化方法。
1.6 [CVPR2017]NID-SLAM: Robust Monocular SLAM using Normalised Information Distance
1.6.1 Contributions
l Robust direct tracking using NID
We present a real-time approach for minimising the NID between a candidate image and a key-frame depth map to recover the sim(3) camera pose. In contrast to previous methods we explicitly incorporate depth uncertainty into the NID score
l Multi-resolution tracking using histogram pyramids
We present a novel histogram-pyramid approach for robust coarse-to-fine tracking using NID which increases robustness and the basin of convergence while reducing computation time at smaller scales
l Direct depth map refinement using NID
We present a per-pixel key-frame depth map refinement approach using NID, which allows for map maintenance and depth updates over successive traversals despite appearance changes over time
1.6.2 Pipeline
1.6.3 NIC
1.6.4 总结
整个NID-SLAM属于直接法的一种,在跟踪的过程中,设计了上述的NID方法,利用联合熵来表达相似性,来代替传统直接法中跟踪部分。实验结果表明,NID-SLAM比ORB-SLAM和LSD的更加鲁棒,姿态估计效果不相上下。
1.7 [TIP2016] Efficient Non-Consecutive Feature Tracking for Structure-from-Motion
1.7.1 Contributions
l Two-Pass Matching for Consecutive Tracking
l Non-Consecutive Track Matching
1.7.2 Feature matching
1.7.3 Matching matrix
1.7.4 总结
l 在匹配阶段,进行两次匹配,第一次通过sift匹配获得少量的较好的匹配结果,然后通过RANSAC 算法生成多个单应矩阵,然后通过单应变换将在同一个平面上的点筛选出来,通过光流做进一步筛选,相当于将提取出来的特征点进行了多个平面归类。
通过连续帧匹配得到的跟踪,对跟踪结果进行评估,生成matching matrix,它表明了非连续帧之间的相关性,对相关性高的帧进行匹配,增加约束。