Runge-Kutta Methods

The implementation of 4th order Runge-Kutta methods using Python.
NOTE: We focus on how to use rk4 to predict the variation of quaternion with value of gyroscope. If someone is interested in IMU kinetics and how to differentiate quaternion w.r.t. time, please refer to Quaternion kinematics for the error-state Kalman filter in section 5.3 and Indirect Kalman Filter for 3D Attitude Estimation in section 1.5.

Future

All quaternion operation functions will be wrapped as a standard package in quaternion_py_tools.

Reference

1. Runge–Kutta methods - Wiki
2. Indirect Kalman Filter for 3D Attitude Estimation
3. Sola, Joan. "Quaternion kinematics for the error-state Kalman filter." arXiv preprint arXiv:1711.02508 (2017).
4. Quaternion Derivative
5. Ordinary Differential Equations - Python