Packages and projects that might be useful
ROS-integrated state estimator for mobile robots. Uses a buffered observation architecture to exactly support out-of-order or delayed information. Also uses a manifold Kalman filter to track SE2 and SE3 poses with a separate linear Kalman filter to track a settable number of higher derivatives (velocity, acceleration, etc.).
A binary angle measurement implementation. Use the python generator script to configure your desired bit widths, resolution etc.