ntrip_ros

Overview

ntrip_ros is an NTRIP client that imports RTCM streams into a ROS topic for real-time kinematic (RTK) GPS correction.

This package was originally forked from tilk/ntrip_ros and has been improved for better reliability, handling of incomplete reads, and reconnection logic.

Features

• Handles RTCM streams from an NTRIP caster and publishes them to a ROS topic.
• Automatically detects and parses messages, handling cases where CORS correction servers do not include /n/r characters.
• Improved error handling, preventing crashes from IncompleteRead exceptions and maintaining a stable connection.
• Supports GPS GGA messages for sending position data to the NTRIP caster.
• Enhanced reconnection logic to detect zero-length data, close, and reopen the stream automatically.

Installation

Dependencies

This package requires the following:

• ROS Melodic
• mavros_msgs (for RTCM messages)
• sensor_msgs (for GPS data)
• rtcm_msgs (if required, from tilk/rtcm_msgs)

Build Instructions

Clone the repository into your catkin workspace:

cd ~/catkin_ws/src
git clone https://github.com/ikh-innovation/ntrip_ros.git
cd ~/catkin_ws
catkin_make
source devel/setup.bash

Usage

Launching the NTRIP Client

To start the NTRIP client, use:

roslaunch ntrip_ros ntrip_ros.launch

Required Parameters

Set these parameters in the launch file or ROS parameter server:

ntrip_server: "your_ntrip_server.com"
ntrip_user: "your_username"
ntrip_pass: "your_password"
ntrip_stream: "mountpoint"
nmea_gga: "$GPGGA,...."  # Replace with a valid GGA message
timeout: 3  # Timeout in seconds

Generating a $GPGGA Message

If you need to generate a $GPGGA message, visit NMEA Generator, set a point near your location, click "Generate NMEA file," and copy the $GPGGA message into your launch file.

Publishing RTCM Data

RTCM messages will be published on:

rostopic echo /rtcm

Related Projects

• ublox_f9p – A ROS driver for the u-blox F9P GNSS receiver.
• dayjaby/ntrip_ros – An alternative NTRIP client for ROS.