Adding Constraints to Bundle Adjustment

[aseyfi]

Hello,

I would like to add some constraints to Bundle Adjustment process. For example, imagine in the environment there are some landmarks that we know their relative locations (e.g. distance between them, or knowing that a group of landmarks are located on the same plane). Assuming that I am using g2o for graph optimization, how this information can be used to improve BA results? Do I need to define a new g2o edge type?

Thank You, Ahmad

[matlabbe]

Currently, OptimizerG2O::OptimizeBA() is adding:

• g2o::VertexCam for graph nodes (e.g., camera poses),
• g2o::EdgeSBACam for graph links between graph nodes (e.g. odometry links),
• g2o::VertexSBAPointXYZ for 3D keypoints and
• g2o::EdgeProjectP2SC for contraints (in term of pixel position of the reprojection in cameras) between 3D keypoints and graph nodes (all based on the BA code example in g2o library). However, I am not sure how to add known constraints (recognized landmarks at known position or add edge between two landmarks/keypoints). You may try asking this question on g2o github. Maybe there is already a kind of edge to describe a constraint between two 3d keypoints.

cheers, Mathieu