inertial_sense

A ROS wrapper for the InertialSense uINS2 GPS-INS sensor

NOTICE:

To use this node, you will likely need to update firmware on your uINS release page

On the release page, there is a Windows graphical utility you can use to update the firmware, or you can use the CLTool, packaged in the SDK to update in linux. I used the following commands to update the firmware to 1.6.2 after downloading the SDK and firmware (change file paths as necesary)

cd InertialSenseSDK-1.6.2/
cd CLTool/
mkdir build
cd build/
cmake ..
make -j4 -l4
./bin/cltool -c=/dev/ttyUSB0 -baud=921600 -b=/home/superjax/Downloads/IS_uINS-3_v1.6.6.0_b2781_2018-06-29_175015.hex 
./bin/cltool -c=/dev/ttyUSB0 -baud=921600 -msgINS2

Installation

This is a ROS package, with the InertialSenseSDK as a submodule, so just create a catkin workspace, clone this into the src folder, pull down the submodule and build

mkdir -p catkin_ws/src
cd catkin_ws/src
catkin_init_workspace
git clone https://inertialsense/inertial_sense
cd inertial_sense
git submodule update --init --recursive
cd ../..
catkin_make

Running the Node

rosrun inertial_sense inertial_sense_node

Make sure that you are a member of the dailout group, or you won't have access to the serial port.

For changing parameter values and topic remapping from the command line using rosrun refer to the Remapping Arguments page. For setting vector parameters, use the following syntax:

rosparam set /inertial_sense_node/GPS_ref_lla "[40.25, -111.67, 1556.59]"
rosrun inertial_sense inertial_sense_node

For setting parameters and topic remappings from a launch file, refer to the Roslaunch for Larger Projects page, or the sample launch/test.launch file in this repository.

Time Stamps

If GPS is available, all header timestamps are calculated with respect to the GPS clock but are translated into UNIX time to be consistent with the other topics in a ROS network. If GPS is unvailable, then a constant offset between uINS time and system time is estimated during operation and is applied to IMU and INS message timestamps as they arrive. There is often a small drift in these timestamps (on the order of a microsecond per second), due to variance in measurement streams and difference between uINS and system clocks, however this is more accurate than stamping the measurements with ROS time as they arrive.

In an ideal setting, there should be no jump in timestamps when GPS is first acquired, because the timestamps should be identical, however, due to inaccuracies in system time, there will likely be a small jump in message timestamps after the first GPS fix.

Topics

Topics are enabled and disabled using parameters. By default, only the ins/ topic is published to save processor time in serializing unecessary messages.

ins/(nav_msgs/Odometry)
- full 12-DOF measurements from onboard estimator (pose portion is from inertial to body, twist portion is in body frame)
imu/(sensor_msgs/Imu)
- Raw Imu measurements from IMU1 (NED frame)
gps/(inertial_sense/GPS)
- unfiltered GPS measurements from onboard GPS unit
gps/info(inertial_sense/GPSInfo)
- sattelite information and carrier noise ratio array for each sattelite
mag (sensor_msgs/MagneticField)
- Raw magnetic field measurement from magnetometer 1
baro (sensor_msgs/FluidPressure)
- Raw barometer measurements in kPa
preint_imu (inertial_sense/DThetaVel)
- preintegrated coning and sculling integrals of IMU measurements

Parameters

~port (string, default: "/dev/ttyUSB0")
- Serial port to connect to
~baud (int, default: 3000000)
- baudrate of serial communication
~frame_id (string, default "body")
- frame id of all measurements

Topic Configuration

~navigation_dt_ms (int, default: 10)
- milliseconds between internal navigation filter updates (min=2ms/500Hz). This is also determines the rate at which the topics are published.
~stream_INS (bool, default: true)
- Flag to stream navigation solution or not
~stream_IMU (bool, default: true)
- Flag to stream IMU measurements or not
~stream_baro (bool, default: 0)
- Flag to stream baro or not
~stream_mag (bool, default: false)
- Flag to stream magnetometer or not
~stream_preint_IMU (bool, default: false)
- Flag to stream preintegrated IMU or not
~stream_GPS(bool, default: false)
- Flag to stream GPS
~stream_GPS_info(bool, default: false)
- Flag to stream GPS info messages

Sensor Configuration

~INS_rpy (vector(3), default: {0, 0, 0})
- The roll, pitch, yaw rotation from the INS frame to the output frame
~INS_xyz (vector(3), default: {0, 0, 0})
- The NED translation vector between the INS frame and the output frame (wrt output frame)
~GPS_ant_xyz (vector(3), default: {0, 0, 0})
- The NED translation vector between the INS frame and the GPS antenna (wrt INS frame)
~GPS_ref_lla (vector(3), default: {0, 0, 0})
- The Reference longitude, latitude and altitude for NED calculation in degrees, degrees and meters
~inclination (float, default: 1.14878541071)
- The inclination of earth's magnetic field (radians)
~declination (float, default: 0.20007290992)
- The declination of earth's magnetic field (radians)
~dynamic_model (int, default: 8)
- Dynamic model used in internal filter of uINS.
  - 0 = portable
  - 2 = stationary
  - 3 = pedestrian
  - 4 = automotive
  - 5 = sea
  - 6 = airborne 1G
  - 7 = airborne 2G
  - 8 = airborne 4G
  - 9 = wrist

ASCII Output Configuration

~ser1_baud_rate (int, default: 115200)
- baud rate for serial1 port used for external NMEA messaging (located on H6-5) serial port hardware connections
~NMEA_rate (int, default: 0)
- Rate to publish NMEA messages
~NMEA_configuration (int, default: 0)
- bitmask to enable NMEA messages (bitwise OR to enable multiple message streams).
  - GPGGA = 0x01
  - GPGLL = 0x02
  - GPGSA = 0x04
  - GPRMC = 0x08
~NMEA_ports (int, default: 0)
- bitmask to enable NMEA message on serial ports (bitwise OR to enable both ports)
  - Ser0 (USB/H4-4) = 0x01
  - Ser1 (H6-5) = 0x02

Services

single_axis_mag_cal (std_srvs/Trigger)
- Put INS into single axis magnetometer calibration mode. This is typically used if the uINS is rigidly mounted to a heavy vehicle that will not undergo large roll or pitch motions, such as a car. After this call, the uINS must perform a single orbit around one axis (i.g. drive in a circle) to calibrate the magnetometer more info
multi_axis_mag_cal (std_srvs/Trigger)
- Put INS into multi axis magnetometer calibration mode. This is typically used if the uINS is not mounted to a vehicle, or a lightweight vehicle such as a drone. Simply rotate the uINS around all axes until the light on the uINS turns blue more info

dallinbriggs/inertial_sense