Duro Inertial GPS Driver

Contents

• Overview
• Scope
• Install
• Settings
• Run
• Topics
• Example rosbag
• Further reading

Overview

This is a C++ ROS driver for Swiftnaw Duro Inertial (Piksi Multi Inertial) GPS / GNSS Receivers. The code is based on offical Swiftnav libswiftnav C example and Alex Hajnal's Apollo UTM converter code. Note that orientation data is produced by Duro Inertial but not produced by Piksi Multi or Duro.

Scope

The current version supports only (not tested elsewhere):

• Ubuntu 18.04
• ROS Melodic
• Catkin tools https://catkin-tools.readthedocs.io/
• Only ethernet version (no serial or USB support)

Install

1. step

Install libsbp (Swift binary protocol library) C client library from GitHub: https://github.com/swift-nav/libsbp It is detailed in github, but the main steps are:

sudo apt-get install build-essential pkg-config cmake doxygen check
cd ~; mkdir git; cd git     # eg create a git folder, the folder name can be different
git clone https://github.com/swift-nav/libsbp.git
cd libsbp
git checkout fe7b78992fb87eef5bd6d12b2daf70f4ac90bc39
cd c
git submodule update --init --recursive
mkdir build; cd build
cmake ../
make
sudo make install

This will create some files in /usr/local/include/libsbp/ and in /usr/local/lib.

2. step

Clone the duro_gps_driver package into your Catkin workspace. Navigate to the root of your Catkin workspace. Source your setup.bash file. Build the duro_ros package using Catkin:

catkin build duro_ros
source devel/setup.bash

Settings

Enable MSG ID 544 and 545 in swift console. Once again, orientation data not produced by Piksi Multi or Duro. These orientation messages are not enabled in default configuration. The MSG ID is defined in the headers, e.g. #define SBP_MSG_ORIENT_QUAT 0x0220 which is decimal 544. Also by defult the magnetometer publishes every 50th message. Change 2306/50 to 2306 in swift console (this message in hex is 0x0902).

Run

Make sure that roscore is running. The duro-gps driver can be run using the rosrun command. It is necessary to provide your device's IP address and port number. E.g:

rosrun duro_ros duronode _ip_address:=192.168.1.10 _port:=55555

Alternatively you can use a launch file. E.g:

roslaunch duro_ros duro_example.launch

Topics

duro_ros duronode publishes the following topics and [types]:

Topic	Type
/gps/duro/current_pose	[geometry_msgs/PoseStamped]
/gps/duro/fix	[sensor_msgs/NavSatFix]
/gps/duro/imu	[sensor_msgs/Imu]
/gps/duro/mag	[sensor_msgs/MagneticField]
/gps/duro/odom	[nav_msgs/Odometry]
/gps/duro/rollpitchyaw	[geometry_msgs/Vector3]
/gps/duro/status_flag	[std_msgs/UInt8]
/gps/duro/status_string	[std_msgs/String]

An important topic is /gps/duro/current_pose which is geometry_msgs/PoseStamped type in UTM (https://en.wikipedia.org/wiki/Universal_Transverse_Mercator_coordinate_system) eg:

header: 
  seq: 5545
  stamp: 
    secs: 1580388036
    nsecs: 641742448
  frame_id: 'map'
pose: 
  position: 
    x: 697214.762607
    y: 5285721.97968
    z: 0.0
  orientation: 
    x: 0.00819693645462
    y: 0.00343747669831
    z: 0.692575566471
    w: 0.721290563233

Example rosbag

Download a sample rosbag, and also a small script to plot the data here or alteratively here.

Further reading

• Libswiftav: https://github.com/swift-nav/libswiftnav
• Libsbp documentation: https://swift-nav.github.io/libsbp/c/build/docs/html
• Libsbp 2.8.0: Protocol specification pdf
• ETH python Piksi ROS drivers: https://github.com/ethz-asl/ethz_piksi_ros