Hi all, this is Josep from Ardusimple.
I found out this thread thanks to one of our customers and I would like to share the configuration that got my simpleRTK2B+heading - Basic Starter Kit working with Ardurover v4.1.0-dev + Pixhawk 4.
Just to clarify, the heading kit is built with a simpleRTK2B and a simpleRTK2Blite boards (piggyback connection).
We will prepare a step by step tutorial at our site but I would like to get your feedback first to know if you could make it work also.
Important things before start (already mentioned in this thread):
- You need RTK fix, so place both antennas in a good location (outdoors, no trees, no high buildings around)
- Place both antennas 1m away of each other (I will use this distance later, you can change it but should be >30cm and <5m).
Place the antennas in the X axis of your rover (forward direction). You can change this later. - Place both antennas in a plane parallel to your autopilot plane (i.e. if your autopilot is horizontal, place both antennas at the same height above ground)
- Do not connect the GNSS receivers with the autpilot yet, we will configure everything independently and connect everything afterwards
- simpleRTK2B (big board) acts as a rover in the moving base configuration
- simpleRTK2Blite (small board) acts as a base in the moving base configuration
Step 1: load simpleRTK2B configuration
- Connect the simpleRTK2B to your PC via the POWER+GPS microUSB connector
- Run u-center and connect to the receivers
- Go to Tools > Receiver Configuration … > Select configuration file simpleRTK2B_FW113_HeadingKit_Rover_10Hz_Ardurover-00.txt (20.9 KB)
- Click Transfer file -> GNSS
- Go to View > Messages View > UBX > CFG > CFG > Select Save current configuration and click Send button
Step 2: load simpleRTK2Blite configuration
- Make sure the simpleRTK2Blite board is mounted on top of the simpleRTK2B board
- Connect the simpleRTK2Blite to your PC via the POWER+XBEE microUSB connector
- Run u-center and connect to the receivers
- Go to Tools > Receiver Configuration … > Select configuration file
simpleRTK2B_FW113_HeadingKit_MovingBase_10Hz_Ardurover-00.txt (20.9 KB) - Click Transfer file -> GNSS
- Go to View > Messages View > UBX > CFG > CFG > Select Save current configuration and click Send button
Step 3: load Pixhawk 4 configuration file for ArduRover 4.1.0-dev
parameters.param (14.5 KB)
Since the hardware and firmware versions may be different to yours, here is a list of all the parameters modified wrt the default configuration:
COMPASS_ENABLE,0
COMPASS_USE,0
COMPASS_USE2,0
COMPASS_USE3,0
EK3_MAG_CAL,5
EK3_SRC1_YAW,2
GPS_AUTO_CONFIG,0
GPS_AUTO_SWITCH,0
GPS_POS1_X,-1.25 *This value must contain the distance between antennas. Change sign if heading has a 180deg offset.
GPS_PRIMARY,1
GPS_TYPE,0
GPS_TYPE2,18
SERIAL1_BAUD,115
SERIAL1_OPTIONS,0
SERIAL1_PROTOCOL,5
SERIAL2_BAUD,115
SERIAL2_OPTIONS,0
SERIAL2_PROTOCOL,5
SERIAL3_BAUD,115
SERIAL3_OPTIONS,0
SERIAL3_PROTOCOL,-1
SERIAL4_BAUD,115
SERIAL4_OPTIONS,0
SERIAL4_PROTOCOL,5
SERIAL5_BAUD,115
SERIAL5_OPTIONS,0
SERIAL5_PROTOCOL,5
SERIAL6_BAUD,115
SERIAL6_OPTIONS,0
SERIAL6_PROTOCOL,5
SERIAL7_BAUD,115
SERIAL7_OPTIONS,0
SERIAL7_PROTOCOL,5
Step 4: connect the heading kit to the Pixhawk 4
- Use the “Pixhawk” connector on the simpleRTK2B (big board) and connect it to the Telem1 port.
- Power Pixhawk 4 and check heading value
- As an additional check to see if it is working, the heading value of the AHRS should be the same as the one in CTRL+F > MAVlink inspector > GPS2_RAW > yaw
Remember, if fix type is not RTK fix, or antenna distance is not within 20% of the GPS1_POS_X parameter or autopilot attitude does not match antenna ehight difference, the GNSS based yaw will not work properly.