Package Overview

Performs sliding-window graph based visual-intertial odometry (VIO) using a VOSmartProjectionFactorAdder and StandstillFactorAdder. Uses a CombinedNavStateNodeAdder for creating combined nav state nodes (containing a pose, velocity, and IMU bias) at required timestamps using IMU measurements. Optionally adds depth image correspondences as point-to-point between factors.

Background

For more information on the theory behind the GraphVIO and the factors used, please see our paper:

Ryan Soussan, Varsha Kumar, Brian Coltin, and Trey Smith, "Astroloc: An efficient and robust localizer for a free-flying robot", Int. Conf. on Robotics and Automation (ICRA), 2022. Link

Graph Optimization Structure

Factor Adders

DepthOdometryFactorAdder
VoSmartProjectionFactorAdder
StandstillFactorAdder

Graph Factors

Point BetweenFactors (for depth odometry correspondences)
CombinedIMUFactor
RobustSmartProjectionFactor
Standstill Factors (zero velocity prior and identity relative transform between factors)

Node Adders

CombinedNavStateNodeAdder