source code

[guoxiaoyang12]

source code: In the Bacckend the regularity fatctors between point and plane may not be added in the optimizaton in open source code now.is this normal?

[ToniRV]

Hi @guoxiaoyang12 , The regularity factors are only added if you use the RegularBackend (see https://github.mit.edu/SPARK/Kimera-VIO/blob/master/params/Euroc/PipelineParams.yaml) And if you set the backend modality (in https://github.mit.edu/SPARK/Kimera-VIO/blob/master/params/Euroc/BackendParams.yaml) to number 4.

Technically speaking, the RegularBackend can be 4 types of backend:

• Structureless backend (aka the vanilla VioBackend)
• Structureless and projection: it will use two types of factors, structureless, and classic re-projection factors
• Projection only: classic re-projection factor
• Projection and Regularity: uses re-projection factors together with regularity factors {
• Structureless, projection, and regularity factors: it will first use structureless factors to be robust to outliers, then it will detect regularities, and for those landmarks that are expected to be on a regularity, it will transform the structureless factor to multiple projection factors together with a regularity factor with other landmarks. For more info, have a read at our paper: https://arxiv.org/abs/1903.01067

See https://github.mit.edu/SPARK/Kimera-VIO/blob/f0f1dc27c889dd16e5e0975fd290b02806959ad3/src/backend/RegularVioBackEnd.cpp#L234 for the code that switches between backend modalities inside the RegularVioBackend.

[guoxiaoyang12]

Thank you for your reply,ToniRV. As shown in the paper,the Mesher thread first calculate the 2D/3D Mesh depends on the current landmarks,secondly,using histograms to get a statistics about the norm of mesh which can calculate the Wall and floor; In the Mesher.cpp ,the spinOnce function call the updateMesh3D function to get the 3D Mesh and update the mesh3d...etc variables, but the variable planes used as Regularity factors may not be update . In other word ,the function clusterPlanesFromMesh which can extract planes may not be called by spinOnce,so plane variable may not be update; I hope to hear from you as soon as possible