Abstract
The VINS-Mono is a monocular visual-inertial 6 DOF state estimator proposed by Aerial Robotics Group of HKUST in 2017. It can be performed on MAVs, smartphones and many other intelligent platforms. Because of the excellent robustness, accuracy and scalability, it has gained extensive attention worldwide. In this manuscript, the main equations including IMU pre-integration, visual-inertial co-initialization and tightly-coupled nonlinear optimization are derived and analyzed.