boat_workspace — ROS 2 ASV Platform

This workspace integrates all drivers, sensors, and data-logging packages for the Catabot autonomous surface vehicle (ASV), a catamaran-style robot developed at Dartmouth College.

Tested on: ROS 2 Humble · NVIDIA Jetson AGX Orin

Packages

Package	Description
catabot_bringup	Top-level orchestration — launches all sensors and drivers
inertiallabs-ros2-pkgs	ROS 2 driver for Inertial Labs INS/IMU/AHRS sensors (fork with local modifications)
ouster-ros	Official Ouster LiDAR ROS 2 driver (OS0/OS1/OS2/OSDome)
rosbag2_composable_recorder	Composable rosbag2 recorder for in-process high-throughput recording
zed_mcap_recorder	Custom composable node for ZED camera data recording to MCAP
zed-ros2-wrapper	Official Stereolabs ZED ROS 2 wrapper (v5.2.2)

inertiallabs-ros2-pkgs

Fork of the upstream Inertial Labs ROS 2 driver with local modifications for the Catabot (composable node, low-latency serial, bug fixes — see the package README for details).

Sub-package	Description
inertiallabs_ins	ROS 2 driver for IL INS/IMU-P/AHRS/AHRS-10 sensors (serial, TCP, or UDP)
inertiallabs_msgs	Custom message definitions (InsData, SensorData, GpsData, GnssData, MarineData)
inertiallabs_sdk	Vendored Inertial Labs C/C++ SDK v0.2 (not a ROS package)

ouster-ros

Official Ouster ROS 2 driver (v0.14.0) for OS0/OS1/OS2/OSDome sensors. See the package README for full usage. The ouster-sdk is included as a git submodule.

Sub-package	Description
ouster_ros	Main driver node (live, record, replay, multicast modes)
ouster_sensor_msgs	Custom messages and services (PacketMsg, GetConfig, SetConfig, etc.)

Catabot config: hostname os-122525001750.local, mode 1024x10, timestamp_mode: TIME_FROM_ROS_TIME (see catabot_bringup/param/os_sensor_cloud_image_params.yaml).

rosbag2_composable_recorder

Composable node wrapper around rosbag2_transport::Recorder. Runs inside the same component container as data-producing nodes to eliminate inter-process serialization overhead. See the package README for parameters and usage.

Only needed for ROS 2 Humble/Iron — Jazzy and later include this capability in standard rosbag2.

zed_mcap_recorder

Custom composable node that records ZED camera compressed images and IMU data to MCAP files. Uses an asynchronous producer–consumer queue to decouple ROS callbacks from disk I/O. See the package README for parameters and usage.

zed-ros2-wrapper

Official Stereolabs ZED ROS 2 wrapper (v5.2.2). Requires ZED SDK v5.2 and CUDA. See the package README for full documentation.

Sub-package	Description
zed_components	Core composable components for all ZED camera models
zed_wrapper	Launch entry-point (zed_camera.launch.py), YAML params, URDF/xacro, RViz2 configs
zed_ros2	Meta-package for workspace discovery
zed_debug	Development-only debug-symbol builds and GDB tooling (skip in field builds)

Build

cd ~/boat_ws
colcon build --symlink-install --cmake-args -DCMAKE_BUILD_TYPE=Release --packages-skip zed_debug
source install/setup.bash

--cmake-args -DCMAKE_BUILD_TYPE=Release optimizes the build but does not exclude zed_debug — --packages-skip zed_debug is still required for that.

---

catabot_bringup for ROS 2

---

Package Structure

catabot_bringup/
├── launch/
│   ├── catabot_bringup.launch.py         # entry-point (selects composable vs. standalone)
│   ├── catabot_bringup_common.launch.py  # main bringup logic with all sensor groups
│   ├── container.launch.xml              # component container for composable mode
│   ├── sensor.composite.launch.py        # composable sensor node loader
│   ├── logger.launch.py                  # rosbag2 recorder
│   ├── zed_camera.launch.py              # per-camera ZED launch helper
│   ├── apm.launch                        # mavros / Pixhawk
│   ├── apm_config.yaml                   # mavros parameters
│   ├── apm_pluginlists.yaml              # mavros plugin whitelist
│   ├── node.launch                       # generic node launch helper
│   └── servo.launch                      # servo controller
├── param/
│   ├── catabot_config.yaml               # platform-level parameters
│   ├── os_sensor_cloud_image_params.yaml # Ouster LiDAR configuration
│   ├── recorder_topics.yaml              # topics recorded by logger
│   └── zed/
│       ├── zedx.yaml                     # ZED-X camera parameters
│       └── common_stereo.yaml            # shared stereo parameters
├── script/
│   ├── startup_bringup.sh                # system startup script
│   ├── startup_docker_lstm.sh            # Docker LSTM inference startup
│   ├── startup_docker_moa.sh             # Docker MOA inference startup
│   ├── startup_imagenex.sh               # Imagenex side-scan sonar startup
│   ├── startup_test.sh                   # test startup script
│   ├── test_connection.sh                # network connectivity test
│   ├── test_topics.py                    # ROS topic sanity check
│   ├── servo_controller.py               # servo control utility
│   ├── read_message_python.py            # message inspection utility
│   └── common_include.sh                 # shared shell functions
└── reqs/
    └── 99-catabot.rules                  # udev rules for USB devices

---

Sensors

Sensor	Driver Package	Key Topic(s)
ZED X x4 (blue/green/red/pink)	zed_wrapper	/<color>/zed/left/color/raw/image, /<color>/zed/imu/data
MiniAHRS	inertiallabs_ins	/imu/data, /Inertial_Labs/ins_data, /Inertial_Labs/gnss_data
Ouster OS1 LiDAR	ouster_ros	/ouster/points, /ouster/scan, /ouster/imu
Surface Camera	usb_cam_surface	/image_raw, /image_raw/compressed, /image_raw/compressedDepth
Pixhawk (mavros)	mavros	/mavros/imu/data, /mavros/global_position/global

---

Launch Arguments

Field recording tip: Use use_composable:=true to run all nodes in a single intra-process container, reducing CPU overhead and serialization latency on the high-bandwidth ZED and LiDAR streams. Set zed_record_root_dir and bag_dir to a path on the NVMe SSD (e.g. /mnt/nova_ssd/datalog/) — writing to the eMMC or SD card will bottleneck recording throughput.

ros2 launch catabot_bringup catabot_bringup.launch.py \
    use_composable:=true \
    use_miniAHRS:=true \
    use_lidar:=true \
    use_zed_blue:=true \
    use_zed_green:=true \
    use_zed_red:=true \
    use_zed_pink:=true \
    use_pixhawk:=true \
    use_logging:=true \
    use_surface_camera:=true \
    use_underwater_camera:=false \
    use_sonde:=false \
    use_sonar:=false \
    use_sidescan:=false

Mode

Argument	Default	Description
use_composable	false	Use intra-process composable node container instead of standalone nodes
robot_name	robot_0	ROS namespace for the robot

Device enable flags

Argument	Default	Description
use_miniAHRS	true	Launch InertialLabs INS driver
use_lidar	true	Launch Ouster LiDAR driver
lidar_ouster	true	Use Ouster driver (vs. Velodyne)
use_ZEDX	true	Enable ZED-X camera mode
use_zed_blue/green/red/pink	true	Enable each ZED camera individually
use_pixhawk	true	Launch mavros (Pixhawk autopilot)
use_logging	true	Start rosbag2 recorder
use_surface_camera	true	Launch USB surface camera
use_underwater_camera	false	Launch USB underwater camera
use_sonde	false	Launch YSI water-quality sonde
use_sonar	false	Launch depth sonar
use_sidescan	false	Launch Imagenex side-scan sonar

InertialLabs miniAHRS

Argument	Default	Description
miniahrs_url	serial:/dev/ttyUSB0:921600	Serial URL: serial:<device>:<baudrate>
ins_output_format	149	InertialLabs output data format ID

Ouster LiDAR

Argument	Default	Description
ouster_host	os-122525001750.local	Sensor hostname or IP
udp_dest	""	UDP destination override (empty = auto)
lidar_mode	1024x10	Scan resolution and rate
viz	false	Launch RViz visualizer

ZED cameras

Argument	Default	Description
zed_camera_model	zedx	ZED camera model
zed_sn_blue/green/red/pink	see launch file	Camera serial numbers
zed_publish_tf	false	Publish odom → zed_camera_link TF
zed_publish_map_tf	false	Publish map → odom TF
zed_publish_imu_tf	false	Publish IMU TF
zed_record_root_dir	/home/catabot-5/datalog/rosbag2	Root directory for ZED recordings
zed_record_session	current timestamp	Session subdirectory name

Device paths

Argument	Default	Description
usb_surface	/dev/surface_cam	Surface camera device
usb_underwater	/dev/video0	Underwater camera device
usb_sonde	/dev/ysi_sonde	YSI sonde serial device
usb_sonar	/dev/sonar	Sonar serial device
usb_pixhawk	udp://:14550@	Pixhawk connection URL
pixhawk_baudrate	57600	Pixhawk serial baudrate
usb_cam_node_start_delay	3.0	Startup delay for surface camera (s)
usb_cam_underwater_start_delay	1.0	Startup delay for underwater camera (s)

---

Timestamp Alignment

All sensors use ROS wall clock (node->now()). Measured offsets vs ZED:

Source	Offset	Notes
ZED IMU	0ms (reference)	—
InertialLabs /imu/data	±30ms	GPS time re-anchored to ROS time in driver
Ouster /ouster/imu	+66ms	Timestamped at packet receipt
Ouster /ouster/points	-126ms	Timestamped at scan start

Ouster configured with timestamp_mode: TIME_FROM_ROS_TIME in os_sensor_cloud_image_params.yaml

---

InertialLabs IMU Rate

The driver publishes /imu/data at ~143–150 Hz with ins_output_format: 149. The format 149 bundles GNSS fields whose update rate, around 27 Hz gates serial packet transmission. The internal IMU sensor runs at 200 Hz but packets are only transmitted when the full INS solution is assembled.

---

IMU Driver Notes

inertiallabs-ros2-pkgs applied serveral changes:

• Removed rclcpp::Rate rate(100) polling loop
• Publisher queue sizes increased from 1 to 10
• MultiThreadedExecutor instead of rclcpp::spin
• SCHED_FIFO realtime priority via setcap cap_sys_nice+ep
• Magnetometer indexing changed (Mag[0/1/2] not all Mag[0])
• Gyro unit conversion to rad/s
• SerialPort.cpp: removed isatty() syscall on every read; poll() timeout reduced from 1000ms to 6ms; VMIN=0, VTIME=0 set for low-latency reads

To apply setcap after each build:

sudo setcap cap_sys_nice+ep \
    ~/boat_ws/install/inertiallabs_ins/lib/inertiallabs_ins/il_ins

---

Systemd Autostart

sudo cp reqs/catabot_bringup.service /etc/systemd/system/
sudo systemctl daemon-reload
sudo systemctl enable catabot_bringup.service

The service waits for network and NVMe mount (/mnt/nova_ssd/data) before launching. Add to /etc/systemd/system/catabot_bringup.service under [Service]:

LimitRTPRIO=99
LimitNICE=-20