# Mahony's AHRS update method

### Description

Mahony's algorithm for AHRS update method.

### Usage

1 2 | ```
MahonyAHRSupdate(gxi, gyi, gzi, axi, ayi, azi, mxi, myi, mzi, sampleFreqi,
twoKpi, twoKii, integralFBxi, integralFByi, integralFBzi, q0i, q1i, q2i, halfex)
``` |

### Arguments

`gxi` |
Gyroscope x axis measurement in radians/s. |

`gyi` |
Gyroscope y axis measurement in radians/s. |

`gzi` |
Gyroscope z axis measurement in radians/s. |

`axi` |
Accelerometer x axis measurement in any calibrated units. |

`ayi` |
Accelerometer y axis measurement in any calibrated units. |

`azi` |
Accelerometer z axis measurement in any calibrated units. |

`mxi` |
Magnetometer x axis measurement in any calibrated units. |

`myi` |
Magnetometer y axis measurement in any calibrated units. |

`mzi` |
Magnetometer z axis measurement in any calibrated units. |

`sampleFreqi` |
Sample frequency. |

`twoKpi` |
Kp constant passed as a parameter |

`twoKii` |
Ki constant passed as a parameter |

`integralFBxi` |
Integral FB[0] |

`integralFByi` |
Integral FB[1] |

`integralFBzi` |
Integral FB[2] |

`q0i` |
Quaternion[0] |

`q1i` |
Quaternion[1] |

`q2i` |
Quaternion[2] |

`halfex` |
Half |

### Value

output quaternion describing the Earth relative to the sensor.

### Author(s)

Jose Gama

### References

S. O. H. Madgwick, An efficient orientation filter for inertial and inertial/magnetic sensor arrays, Technical report, University of. Bristol University, UK, 2010.

R. Mahony, T. Hamel, and J.-M. Pflimlin. Nonlinear complementary filters on the special orthogonal group. Automatic Control, IEEE Transactions on, 53(5):1203 –1218, june 2008.