## Documentation |

Implement three-axis gyroscope

The Three-Axis Gyroscope block implements a gyroscope on each of the three axes. The measured body angular rates $$({\overline{\omega}}_{meas})$$ include the body angular rates $$({\overline{\omega}}_{b})$$, errors, and optionally discretizations and nonlinearizations of the signals.

$${\overline{\omega}}_{meas}={\overline{\omega}}_{b}\times {\overline{\omega}}_{SFCC}+{\overline{\omega}}_{bias}+Gs\times {\overline{\omega}}_{gsens}+noise$$

where $${\overline{\omega}}_{SFCC}$$ is a 3-by-3 matrix of scaling
factors on the diagonal and misalignment terms in the nondiagonal, $${\overline{\omega}}_{bias}$$ are the biases, (*Gs*)
are the Gs on the gyroscope, and $${\overline{\omega}}_{gsens}$$ are
the g-sensitive biases.

Optionally discretizations can be applied to the block inputs and dynamics along with nonlinearizations of the measured body angular rates via a Saturation block.

**Second order dynamics**Select to apply second-order dynamics to gyroscope readings.

**Natural frequency (rad/sec)**The natural frequency of the gyroscope. The units of natural frequency are radians per second.

**Damping ratio**The damping ratio of the gyroscope. A dimensionless parameter.

**Scale factors and cross-coupling**The 3-by-3 matrix used to skew the gyroscope from body axes and to scale angular rates along body axes.

**Measurement bias**The three-element vector containing long-term biases along the gyroscope axes. The units are in radians per second.

**G-sensitive bias**The three-element vector contains the maximum change in rates due to linear acceleration. The units are in radians per second per g-unit.

**Update rate (sec)**Specify the update rate of the gyroscope. An update rate of 0 will create a continuous gyroscope. If noise is selected and the update rate is 0, then the noise will be updated at the rate of 0.1. The units of update rate are seconds.

**Noise on**Select to apply white noise to gyroscope readings.

**Noise seeds**The scalar seeds for the Gaussian noise generator for each axis of the gyroscope.

**Noise power**The height of the PSD of the white noise for each axis of the gyroscope.

**Lower and upper output limits**The six-element vector containing three minimum values and three maximum values of angular rates in each of the gyroscope axes. The units are in radians per second.

Input | Dimension Type | Description |
---|---|---|

First | Three-element vector | Contains the angular rates in body-fixed axes, in radians per second. |

Second | Three-element vector | Contains the accelerations in body-fixed axes, in Gs. |

Output | Dimension Type | Description |
---|---|---|

First | Three-element vector | Contains the measured angular rates from the gyroscope, in radians per second. |

Anisoelastic bias and anisoinertial bias effects are not accounted for in this block. Additionally, this block is not intended to model the internal dynamics of different forms of the instrument.

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