The Station Motion Model implements a complete station motion model based on IERS Technical Note 32 (IERS Conventions 2003). This model includes the effects of tectonic plate motion, solid Earth tides, ocean tide loading and the pole tide. To use the model, set the following attributes in the Object Properties window for a facility:

Property | Description |
---|---|

PositionType | Select the MeanTide or TideFree option. The TideFree option indicates that the input position of the facility will be interpreted as a Conventional Tide Free position. The MeanTide option indicates that the input position of the facility will be interpreted as a Mean Tide position. The relationship between the Tide Free and Mean Tide positions is given by IERS Technical Note 32 (IERS Conventions 2003), section 7.1.3. |

ModelStationMotion | Select true to enable the station motion model, which allows for the optional accounting of station location variation due to tectonic plate motion, solid Earth tide effects, ocean tide loading effects and the tidal effects due to pole wander. The station motion model follows IERS Technical Note 32 (IERS Conventions 2003), chapter 7. When the station motion model is not enabled, the Mean Tide position (either as input or as computed from an input Tide Free position) is used for the purpose of measurement modeling. |

MotionModel.PlateMotion | Select true to model the effects of tectonic plate motion. This model requires the input of an epoch for the given station location and a constant velocity in terms of cm/year. |

MotionModel.Epoch | Epoch for the input position of facility. Used in the computation of the tectonic plate motion. |

MotionModel.Velocity | Velocity due to tectonic plate motion given in Earth-Centered Earth-Fixed coordinates in units of cm/year. |

MotionModel.OceanTideLoading | Select true to model the effects of ocean tide loading. Model is equivalent to the model specified in IERS Technical Note 32 (IERS Conventions 2003), section 7.1.1. Successful application of the ocean loading model requires that an ocean loading coefficient file be specified. |

MotionModel.OceanTideLoadingFile | Ocean loading coefficient file in HARPOS format. Required for the application of ocean loading. Files of the appropriate format may be generated through the following web site: http://holt.oso.chalmers.se/loading/. Be careful to select the HARPOS format. |

MotionModel.SolidEarthTides | Select true to model the effects of solid Earth tides. Model is as specified in IERS Technical Note 32 (IERS Conventions 2003), section 7.1.2. |

MotionModel.PoleTide | Select true to model the effects of the pole tide. Model is as specified in IERS Technical Note 32 (IERS Conventions 2003), section 7.1.4. |

As exemplified in the accompanying sample of the Ocean Loading file format expected by ODTK, the current implementation assumes one facility per file.

ODTK 6.5