VOXL2 microdds agent namespace

[Darshit Desai]

Hi @Moderator I am wondering if I can change the namespace as mentioned in the PX4-ROS2 docs here https://docs.px4.io/main/en/ros/ros2_comm.html#customizing-the-topic-namespace . I have 5 starlings in a swarm and I fear that at some point all of them might be subscribing or publishing to the same topic

[Moderator]

@Darshit-Desai it doesn't seem voxl-mpa-to-ros2 supports that today. Have you thought about modifying the code to add that feature?

[Darshit Desai]

@Moderator Actually this is related to MicroUXRCE Agent for streaming PX4 FMU uORB topics as ROS2 topics, there is a way to rename the namespace for that but in MODAL AI I am not sure. MPATOROS2 is perfectly fine, I can just change the namespace using this command and that is not the issue here: ros2 run voxl_mpa_to_ros2 voxl_mpa_to_ros2_node --ros-args -r __ns:=/drone3. I am talking about when there is no mpatoros2 node running and the Microdds agent streams the PX4 uorb topics as shown below:

[Darshit Desai]

@Moderator THe only way to change microdds namespace is through QGC I tried that and it worked, but the issue is I need to manually type it up on each bootup of the FMU. As shown below:

Microdds service stopped and started with a namespace

Topics remapped on VOXL2

So I thought I could change the voxl-px4.conf to include this as a qshell command but that also didn't work as shown below

voxl-px4.conf file v1

voxl-px4.conf file v2

Both versions resulted in the Error in the restart/power cycle of systemd service

[Eric Katzfey]

@Darshit-Desai Rather than modifying voxl-px4.conf to use EXTRA_STEPS, can you try directly modifying /usr/bin/voxl-px4-start and adding that command?

[Darshit Desai]

Hi @Eric-Katzfey that worked, now I actually want to export a variable which states the namespace of the relevant drone and the voxl-px4-start file picks up that variable and assigns the namespace but I am facing some errors because of that, could you have a look

Here's my bashrc file

#!/bin/bash
# ModalAI default bashrc file

#VERSION 1.2

# If not running interactively, don't do anything
case $- in
    *i*) ;;
      *) return;;
esac

# don't put duplicate lines or lines starting with space in the history.
# See bash(1) for more options
HISTCONTROL=ignoreboth

# append to the history file, don't overwrite it
shopt -s histappend

# for setting history length see HISTSIZE and HISTFILESIZE in bash(1)
HISTSIZE=1000
HISTFILESIZE=2000

# check the window size after each command and, if necessary,
# update the values of LINES and COLUMNS.
shopt -s checkwinsize

# ubuntu ssh sets TERM to xterm-256color which screws with ROS
# change it to linux spec
export TERM=linux

if [ -d /home/root/.profile.d/ ]; then
  for i in /home/root/.profile.d/* ; do
    if [ -d $i ]; then
        for j in $i/* ; do
            if [ -f $j ]; then
                . $j
            fi
        done
    else
        . $i
    fi
  done
fi

# Put user-specific tweaks here or in a file in ~/.profile.d/
export PX4_NAMESPACE="uav_1"

Here's my voxl-px4-start file

#!/bin/sh
# PX4 commands need the 'px4-' prefix in bash.
# (px4-alias.sh is expected to be in the PATH)
. px4-alias.sh

echo -e "\n*************************"
echo "GPS: $GPS"
echo "RC: $RC"
echo "ESC: $ESC"
echo "POWER MANAGER: $POWER_MANAGER"
echo "DISTANCE SENSOR: $DISTANCE_SENSOR"
echo "OSD: $OSD"
echo "EXTRA STEPS:"
for i in "${EXTRA_STEPS[@]}"
do
	echo -e "\t$i"
done
echo -e "*************************\n"

# In order to just exit after starting the uorb / muorb modules define
# the environment variable MINIMAL_PX4. (e.g. export MINIMAL_PX4=1)
# This is useful for testing / debug where you may want to start drivers
# and modules manually from the px4 command shell
if [ ! -z $MINIMAL_PX4 ]; then
    /bin/echo "Running minimal script"
    exit 0
fi

# Figure out what platform we are running on.
PLATFORM=`/usr/bin/voxl-platform 2> /dev/null`
RETURNCODE=$?
if [ $RETURNCODE -ne 0 ]; then
    # If we couldn't get the platform from the voxl-platform utility then check
    # /etc/version to see if there is an M0052 substring in the version string. If so,
    # then we assume that we are on M0052.
    VERSIONSTRING=$(</etc/version)
    M0052SUBSTRING="M0052"
    if [[ "$VERSIONSTRING" == *"$M0052SUBSTRING"* ]]; then
        PLATFORM="M0052"
    fi
fi

# We can only run on M0052, M0054, or M0104 so exit with error if that is not the case
if [ $PLATFORM = "M0052" ]; then
    /bin/echo "Running on M0052"
elif [ $PLATFORM = "M0054" ]; then
    /bin/echo "Running on M0054"
elif [ $PLATFORM = "M0104" ]; then
    /bin/echo "Running on M0104"
else
    /bin/echo "Error, cannot determine platform!"
    exit 0
fi

# Sleep a little here. A lot happens when the uorb and muorb start
# and we need to make sure that it all completes successfully to avoid
# any possible race conditions.
/bin/sleep 1

param select /data/px4/param/parameters

# Load in all of the parameters that have been saved in the file
param load

# Start logging and use timestamps for log files when possible.
# Add the "-e" option to start logging immediately. Default is
# to log only when armed. Caution must be used with the "-e" option
# because if power is removed without stopping the logger gracefully then
# the log file may be corrupted.
logger start -t

# IMU (accelerometer / gyroscope)
if [ "$PLATFORM" == "M0104" ]; then
    /bin/echo "Starting IMU driver with rotation 12"
    qshell icm42688p start -s -R 12
else
    /bin/echo "Starting IMU driver with no rotation"
    qshell icm42688p start -s
fi

# Start Invensense ICP 101xx barometer built on to VOXL 2
qshell icp101xx start -I -b 5

# Auto detect the magnetometer. If one or both of these devices
# are not connected it will fail but not cause any harm.
/bin/echo "Looking for qmc5883l magnetometer"
qshell qmc5883l start -R 10 -X -b 1
/bin/echo "Looking for ist8310 magnetometer"
qshell ist8310 start -R 10 -X -b 1

# GPS and magnetometer
if [ "$GPS" != "NONE" ]; then
	# On M0052 the GPS driver runs on the apps processor
	if [ $PLATFORM = "M0052" ]; then
	    gps start -d /dev/ttyHS2
	# On M0054 and M0104 the GPS driver runs on SLPI DSP
	else
	    qshell gps start
	fi
fi

# Auto detect an ncp5623c i2c RGB LED. If one isn't connected this will
# fail but not cause any harm. 
/bin/echo "Looking for ncp5623c RGB LED"
qshell rgbled_ncp5623c start -X -b 1 -f 400 -a 56

# We do not change the value of SYS_AUTOCONFIG but if it does not
# show up as used then it is not reported to QGC and we get a
# missing parameter error.
param touch SYS_AUTOCONFIG

# ESC driver
if [ "$ESC" == "VOXL_ESC" ]; then
    /bin/echo "Starting VOXL ESC driver"
	qshell voxl_esc start
elif [ "$ESC" == "VOXL2_IO_PWM_ESC" ]; then
	if [ "$RC" == "M0065_SBUS" ]; then
		/bin/echo "Starting VOXL IO for PWM ESC with SBUS RC"
		qshell voxl2_io start
	else
		/bin/echo "Starting VOXL IO for PWM ESC without SBUS RC"
		qshell voxl2_io start -e
	fi
else
	/bin/echo "No ESC type specified, not starting an ESC driver"
fi


# RC driver
if [ "$RC" == "FAKE_RC_INPUT" ]; then
    /bin/echo "Starting fake RC driver"
    qshell rc_controller start
elif [ "$RC" == "CRSF_RAW" ]; then
    /bin/echo "Starting CRSF RC driver"
    qshell crsf_rc start -d 7
elif [ "$RC" == "CRSF_MAV" ]; then
    /bin/echo "Starting TBS crossfire RC - MAV Mode"
    qshell mavlink_rc_in start -m -p 7 -b 115200
elif [ "$RC" == "SPEKTRUM" ]; then
    /bin/echo "Starting Spektrum RC"
	# On M0052 the RC driver runs on the apps processor
	if [ $PLATFORM = "M0052" ]; then
        rc_input start -d /dev/ttyHS1
	# On M0054 and M0104 the RC driver runs on SLPI DSP
	else
        qshell spektrum_rc start
	fi
elif [ "$RC" == "GHST" ]; then
    /bin/echo "Starting GHST RC driver"
    qshell ghst_rc start -d 7
elif [ "$RC" == "M0065_SBUS" ]; then
	if [ $PLATFORM = "M0052" ]; then
		apps_sbus start
	elif [ "$ESC" != "VOXL2_IO_PWM_ESC" ]; then
    	/bin/echo "Attempting to start M0065 SBUS RC driver for original M0065 FW"
    	qshell dsp_sbus start
		retVal=$?
		if [ $retVal -ne 0 ]; then
	    	/bin/echo "Starting M0065 SBUS RC driver for original M0065 FW failed"
	    	/bin/echo "Attempting to start M0065 SBUS RC driver for new M0065 FW"
			qshell voxl2_io start -d -p 7
		fi
	else
    	/bin/echo "M0065 SBUS RC driver already started with PWM ESC start"
	fi
fi

if [ "$DISTANCE_SENSOR" == "LIGHTWARE_SF000" ]; then
	# Make sure to set the parameter SENS_EN_SF0X to 8 for sf000/b sensor
	qshell lightware_laser_serial start -d 7
fi

if [ "$POWER_MANAGER" == "VOXLPM" ]; then
	# APM power monitor
	qshell voxlpm start -X -b 2
fi

# Optional distance sensor on spare i2c
# qshell vl53l0x start -X -b 4
# qshell vl53l1x start -X -b 4

# Start all of the processing modules on DSP
qshell sensors start
qshell ekf2 start
qshell mc_pos_control start
qshell mc_att_control start
qshell mc_rate_control start
qshell mc_hover_thrust_estimator start
qshell mc_autotune_attitude_control start
qshell land_detector start multicopter
qshell manual_control start
qshell control_allocator start
qshell load_mon start

# Only start the rc_update module if an actual RC driver
# is publishing input_rc topics. Otherwise for external RC
# over Mavlink this isn't needed.
if [ "$RC" != "EXTERNAL" ]; then
	qshell rc_update start
fi

qshell commander start

# This is needed for altitude and position hold modes
qshell flight_mode_manager start

# Start all of the processing modules on the applications processor
dataman start
navigator start
load_mon start

# This bridge allows raw data packets to be sent over UART to the ESC
modal_io_bridge start

# Start microdds_client for ros2 offboard messages from agent over localhost
microdds_client start -t udp -h 127.0.0.1 -p 8888 -n $PX4_NAMESPACE

# On M0052 there is only one IMU. So, PX4 needs to
# publish IMU samples externally for VIO to use.
if [ $PLATFORM = "M0052" ]; then
	imu_server start
fi

# start the onboard fast link to connect to voxl-mavlink-server
mavlink start -x -u 14556 -o 14557 -r 100000 -n lo -m onboard

# slow down some of the fastest streams
mavlink stream -u 14556 -s HIGHRES_IMU -r 10
mavlink stream -u 14556 -s ATTITUDE -r 10
mavlink stream -u 14556 -s ATTITUDE_QUATERNION -r 10
mavlink stream -u 14556 -s GLOBAL_POSITION_INT -r 30
mavlink stream -u 14556 -s SCALED_PRESSURE -r 10

# start the slow normal mode for voxl-mavlink-server to forward to GCS
mavlink start -x -u 14558 -o 14559 -r 100000 -n lo

mavlink boot_complete

# Optional MSP OSD driver for DJI goggles
# This is only supported on M0054 (with M0125 accessory board)
if [ "$OSD" == "ENABLE" ]; then
    /bin/echo "Starting OSD driver"
    msp_osd start -d /dev/ttyHS1
fi

# Start optional EXTRA_STEPS
for i in "${EXTRA_STEPS[@]}"
do
	$i
done

The errors that I get:

[Eric Katzfey]

@Darshit-Desai Seems like some bash scripting issues. Perhaps echo $PX4_NAMESPACE before the microdds_client start line to see what is in that variable.

[Darshit Desai]

@Eric-Katzfey I know this is a question for the px4 forum, but can you guys help me figure out how to run the https://github.com/PX4/px4_ros_com/blob/main/src/examples/offboard/offboard_control_srv.cpp service server here. I changed the namespace for my microdds client as you know and I am not sure if that service server is running or not, I can't find the server when I do ros2 service list or ros2 service find