This project is aimed at estimating the attitude of Attitude Heading and Reference System(AHRS). And the project contains three popular attitude estimator algorithms.

• Mahony's algorithm
• Extend Kalman Filter(EKF)
• Error State Kalman Filter(ESKF)

DataSets.py for converting estimator data.
Allan_Analysis for Allan Variance analysis.

[1] Mahony R, Hamel T, Pflimlin J M. Nonlinear complementary filters on the special orthogonal group[J]. IEEE Transactions on automatic control, 2008, 53(5): 1203-1218.
[2] Pixhawk state estimation
[3] Solà, Joan. Quaternion kinematics for the error-state Kalman filter[J]. 2017.
[4] Trawny N, Roumeliotis S I. Indirect Kalman Filter for 3D Attitude Estimation[J]. 2005.

• Eigen3.2.0
• glog

sudo apt-get install libgoogle-glog-dev

• matplotlib-cpp

Simple comparision among three methods. And the params of Mahony filter can be further tuned.