Instruct: Identify the main and secondary category of Arxiv papers based on the titles and abstracts
Query: Stereo Camera Visual SLAM with Hierarchical Masking and Motion-state
  Classification at Outdoor Construction Sites Containing Large Dynamic Objects   At modern construction sites, utilizing GNSS (Global Navigation Satellite
System) to measure the real-time location and orientation (i.e. pose) of
construction machines and navigate them is very common. However, GNSS is not
always available. Replacing GNSS with on-board cameras and visual simultaneous
localization and mapping (visual SLAM) to navigate the machines is a
cost-effective solution. Nevertheless, at construction sites, multiple
construction machines will usually work together and side-by-side, causing
large dynamic occlusions in the cameras' view. Standard visual SLAM cannot
handle large dynamic occlusions well. In this work, we propose a motion
segmentation method to efficiently extract static parts from crowded dynamic
scenes to enable robust tracking of camera ego-motion. Our method utilizes
semantic information combined with object-level geometric constraints to
quickly detect the static parts of the scene. Then, we perform a two-step
coarse-to-fine ego-motion tracking with reference to the static parts. This
leads to a novel dynamic visual SLAM formation. We test our proposals through a
real implementation based on ORB-SLAM2, and datasets we collected from real
construction sites. The results show that when standard visual SLAM fails, our
method can still retain accurate camera ego-motion tracking in real-time.
Comparing to state-of-the-art dynamic visual SLAM methods, ours shows
outstanding efficiency and competitive result trajectory accuracy.

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The categories of this paper are: physics
22
The categories of this paper are: chao-dyn
8
The categories of this paper are: hep-ex
5
The categories of this paper are: gr-qc
17
The categories of this paper are: q-fin
31
The categories of this paper are: ao-sci
36
The categories of this paper are: cmp-lg
34
The categories of this paper are: chem-ph
9
The categories of this paper are: nlin
18
The categories of this paper are: econ
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The categories of this paper are: hep-ph
12
The categories of this paper are: nucl-th
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The categories of this paper are: supr-con
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The categories of this paper are: nucl-ex
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The categories of this paper are: atom-ph
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The categories of this paper are: alg-geom