Implemented Stereo Visual Odometry and Visual Inertial Odometry pipelines to estimate the pose of a quad-rotor. The system works by taking subsequent image pairs and matching features throughout the test. Once those features are obtained, 3d-points coordinates were retrieved with the depth map of the images and the extrinsic camera calibration matrix. Finally, the trajectory is estimated using 3D-2D Perspective-n-Point (PNP). As an additional step, the VO trajectory was used with the IMU data in an Error-State Extended Kalman Filter to estimate the pose even when most of the VO observations were dropped. Both VO and VIO showed good results estimating the trajectory of the UAV (Implemented in Python/Linux).