IRT GNSS Pre-Processing

This is the official package of irt_gnss_preprocessing. The package provide a ros wrapper and sevral interfaces of popular GNSS receivers to GNSS pre-processing algorithms and modules.

The package is designed with the concept of pluginlib. The interface to each receiver is implemented as a plugin so that it can be configured in the configuration file.

The details of processing logics and algorithms will be updated later.

Currently, only ROS2 is supported, the ROS1 version is in development.

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Dependencies:

1. ros2
2. irt_nav_common
3. GTSAM (dependency will be removed in next push)
4. Eigen3
5. novatel_oem7_msgs
6. ublox_msgs
7. ublox_serialization

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Suported GNSS Receivers:

1. NovAtel OEM7 (e.g., pwrpak7 or span)
2. Ublox F9P (still in progress)

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How to start

ros2 launch irt_gnss_preprocessing gnss_preprocessor.launch.py 

Papers using this package

[1] Haoming Zhang, Chih-Chun Chen, Heike Vallery and Timothy D. Barfoot, GNSS/Multi-Sensor Fusion Using Continuous-Time Factor Graph Optimization for Robust Localization, submitted to IEEE T-TRO, arxiv, DOI: 10.48550/arXiv.2309.11134

[2] Haoming Zhang, Zhanxin Wang and Heike Vallery, Learning-based NLOS Detection and Uncertainty Prediction of GNSS Observations with Transformer-Enhanced LSTM Network, accepted for the IEEE ITSC2023, arxiv, DOI: 10.48550/arXiv.2309.00480

[3] Haoming Zhang, Xiao Xia, Maximilian Nitsch and Dirk Abel, Continuous-Time Factor Graph Optimization for Trajectory Smoothness of GNSS/INS Navigation in Temporarily GNSS-Denied Environments, IEEE Robotics and Automation Letters (RAL), DOI: [10.1109/LRA.2022.3189824](https://doi.org/10.1109/LRA.2022.3189824

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ToDos:

1. generate wiki for GNSS algorithms
2. generate wiki for parameters in the config file
3. test ublox interface