NTRTP Client for ROS

Authors Maintainers: Damon (Email: wxtcon@gmail.com)

Have you ever found that your u-blox receiver just won't cooperate with your RTK dreams when using the ublox_driver?

Fear not, for ntrip_client is here to save the day! This handy tool is designed to bridge the gap between your u-blox receiver and NTRIP required to upload GGA messages, such as Qianxun CORS and China Mobile CORS.

Here's what ntrip_client brings to the table:

GGA Message Generation: Subscribe and parse the /ublox_driver/receiver_pvt topic and craft GGA messages to feed NTRIP casters.
RTCM Stream Relay: Once ntrip_client is up and running, it slurps up RTCM streams and forwards them to your u-blox receiver through a port of your choosing.
No Extra Gadgets Required: Forget about fancy USB-to-TTL modules and other unnecessary accessories. All you need is a computer and a u-blox receiver with a GNSS antenna (like the ublox_f9p), and you're good to go!
Reconnect if the network connection fails, ensuring uninterrupted communication.

1. Prerequisites

1.1 C++ 11 Compiler

This package requires some features of C++11.

1.2 ROS

Make sure your ROS version is above ROS melodic.

1.3 Eigen

The Eigen 3.3.3 is adopted for matrix manipulation.

1.4 gnss_comm

This package requires gnss_comm for ROS message definitions and some utility functions. Follow those instructions to build the gnss_comm package.

1.5 ublox_driver

ublox_driver is used for receiver ublox messages from f9p module and get the PPP soultion. Ntrip_client also need the ros topic from ublox_driver.

2. Build ntrip_client

Clone the repository to your catkin workspace (for example ~/catkin_ws/):

cd ~/catkin_ws/src/
git clone https://github.com/wxtcon/ntrip_client.git

Then build the package with:

cd ~/catkin_ws/
catkin_make
source ~/catkin_ws/devel/setup.bash

3. Run with you F9P module

First you need to configure RTCM-related information, which is located in the ./config/ntrip_config.yaml file.

server_ip:     NTRIP caster IP ,such as 120.253.239.161(China mobile)
server_port:   NTRIP caster TCP Port, such as 8002. In general, different ports correspond to different geodetic coordinate systems, such as 8002 for WGS84
mountpoint:    NTRIP caster mount point, which relates your RTK device.
user:          user name. if you NTRIP caster needn't it, Please ignore this item or use the email name instead(such as RTK2go NTRIP Caster)
passwd:        password. if you NTRIP caster needn't it, Please ignore this item or use "none"(such as RTK2go NTRIP Caster)
transfer_port: TCM tranfer port, If you use ublox_driver, it should default to 3503.
transfer_ip:   RTCM tranfer IP. No modification is usually required if the ublox_driver is running on the same computer as the ntrip_client

Run ntrip_client Make sure your computer has access to the Internet. Then, Use the following command to run ntrip_client.

roslaunch ntrip_client start_ntrip_client.launch

If everything is OK, you should see the following message printed in your ubuntu terminal

[ INFO] [1710616230.433886318]: The TCP service is started, IP address: 127.0.0.1, Port: 3503
[ INFO] [1710616230.433960774]: Start listening the client...

Run ublox_driver Ensure that ublox_driver is configured and rtcm reception is turned on.

Use the following command to run ublox_driver.

roslaunch ublox_driver ublox_driver.launch

ntrip_client will print the following message:

[ INFO] [1710616334.436246253]: Client access!--------

At this point, all communications are established.

Check the RTK solution states. You can print the /ublox_driver/receiver_pvt topic to Check the RTK solution states.

rostopic echo /ublox_driver/receiver_pvt

If the item carr_soln of topic /ublox_driver/receiver_pvt turning to2, which means RTK fixed solution.(0 means not RTK solution, and 1 means RTK float solution)

Now, enjoy it.

4. Notation

Due to the short development time, this is an imperfect program. We look forward to your valuable suggestions by submitting issues and other means.

5. Acknowledgements

In the process of development, we have referred to the excellent works of ublox_driver, gnss_comm, NTRIP_ROS, etc., and we would like to thank them all.

wxtcon/ntrip_ros