ARGOS Autonomous Room Geometry Optical Scanner

OpenVINS mono+IMU VIO → RTABMAP mapping / loop closure across two Raspberry Pis and an amd64 laptop. ROS 2 Humble, CycloneDDS multi-host, Foxglove, chrony time sync. Offline COLMAP on the two Vivotek streams.

Standalone — does not depend on ORB-SLAM3 or orbslam3_docker/. VINS-Fusion has been removed in favor of OpenVINS.

Why this architecture

RTABMAP’s rgbd_odometry expects RGB-D (or is a weak mono VO substitute). For calibrated mono + IMU:

1. OpenVINS estimates visual-inertial odometry from Blackfly images + raw IMU.
2. RTABMAP consumes that external odometry plus lidar (preferred) and/or mono camera_info for mapping and loop closure.
3. OpenVINS does not own LC — RTABMAP does.
4. No Madgwick into OpenVINS — raw sensor_msgs/Imu only.
5. 2× Vivotek are photogrammetry cameras only (COLMAP bags) — not the VIO FE.

Pi B Blackfly+IMU ──► OpenVINS ──/ov_msckf/odomimu──┐  (DDS)
Pi B 2× Vivotek ────► COLMAP bags (offline)         │
Pi A LiDAR ──/scan (local)──────────────────────────┼──► RTABMAP on Pi A (preferred)
                                                    ├──► Foxglove / laptop (subscribe)
                                                    └──► rosbag2 (optional)

CycloneDDS: the laptop subscribes — no Pi “forward” hop. Bandwidth is the real constraint (do not stream three raw cameras live to the laptop).

Hardware topology (3 roles)

Host	Hardware	Sparse paths	Runs
Pi B (VIO)	Blackfly + IMU + 2× Vivotek	shared + pi → pi/vio	OpenVINS on Blackfly+IMU; COLMAP record for Vivoteks
Pi A (lidar)	LiDAR	shared + pi → pi/lidar	/scan + native RTABMAP (preferred)
Laptop	amd64	shared + laptop	Live map showcase; offline COLMAP / CloudCompare

Details: shared/docs/topology.md.
Time sync: shared/docs/time_sync.md (chrony default).

Storage

Host	Disk	Policy
Pi A (lidar / RTABMAP)	256 GB	Staging for maps, RTABMAP DBs, bags — then rsync to laptop
Pi B (VIO)	32 GB	Lean only: short buffers; dump COLMAP / Vivotek recordings to the 256 GB Pi or laptop often
Laptop	—	COLMAP compute + long-term archive of rsynced data

CycloneDDS peers (same ROS_DOMAIN_ID everywhere):

PI_LIDAR_IP=…   # Pi A
PI_VIO_IP=…     # Pi B
LAPTOP_IP=…

Recommended realtime load split

1. Pi B: OpenVINS only (Blackfly+IMU); record/subsample Vivoteks for COLMAP; optional lightweight Foxglove.
2. Pi A: LiDAR driver + native RTABMAP on /ov_msckf/odomimu from Pi B + local /scan — saves VIO CPU and keeps lidar local to the mapper.
3. Laptop: Join domain for Foxglove/RViz (whitelist: odom, map, cloud/scan compressed — not raw 3-camera live).

Alternatives: RTABMAP on VIO Pi (simpler if already set up); RTABMAP live on laptop (max Pi headroom, needs good Wi‑Fi).

Repository layout

argos/
  README.md
  LICENSE
  shared/                 # pull on every machine
    .env.example          # IPs + Blackfly / Vivotek / IMU / lidar / OV odom
    config/               # CycloneDDS, RTABMAP, OpenVINS, Foxglove
    docs/                 # topology + time_sync
    scripts/              # chrony, DDS render, install_openvins.sh
    calib/
  pi/
    README.md
    vio/                  # Pi B — OpenVINS + COLMAP recording
    lidar/                # Pi A — lidar + preferred RTABMAP entrypoint
  laptop/                 # amd64: showcase + offline COLMAP / analysis

Sparse-checkout

Either Pi (then use only vio/ or lidar/):

git sparse-checkout init --cone
git sparse-checkout set argos/README.md argos/LICENSE argos/shared argos/pi

Laptop:

git sparse-checkout init --cone
git sparse-checkout set argos/README.md argos/LICENSE argos/shared argos/laptop

Quick start (preferred order)

1. Env + clocks (all hosts)

cp shared/.env.example pi/vio/.env      # or pi/lidar/.env or laptop/.env
# Edit peer IPs, CHRONY_NTP_SERVER, Blackfly / Vivotek / IMU / lidar topics
sudo ./shared/scripts/setup_chrony.sh   # on both Pis (and laptop if needed)

2. Pi B — OpenVINS (+ optional COLMAP record)

cd pi/vio
./scripts/build.sh && ./scripts/run.sh           # Docker OpenVINS (no RTABMAP in image)
./scripts/record_colmap.sh                       # Vivotek mcap for offline COLMAP
# optional: ./scripts/run.sh recording           # general session bag

3. Pi A — lidar + native RTABMAP (preferred mapper)

cd pi/lidar
./scripts/run.sh                                 # vendor driver → /scan
RTABMAP_USE_LIDAR=true ./scripts/run_rtabmap_host.sh

4. Laptop — live map showcase / offline

cd laptop
./scripts/build.sh
./scripts/run.sh monitor                         # subscribe: odom / map / scan
# Offline: COLMAP on Vivotek bags; CloudCompare align to RTABMAP/lidar cloud
# Foxglove: bag review or ws://<PI_LIDAR_IP|PI_VIO_IP>:8765

Mapping host policy

Preferred: native RTABMAP on Pi A consumes OV odom over DDS + local /scan. Set RTABMAP_USE_LIDAR=true after chrony sync and extrinsics are solid.

Legacy path: pi/vio/scripts/run_rtabmap_host.sh (RTABMAP on VIO Pi). Laptop can map offline from bags with use_sim_time + --clock.

Compose profiles

Location	Service	Profile	Role
pi/vio	openvins	default	OpenVINS + Foxglove
pi/vio	recorder	recording	general rosbag2 mcap
pi/vio	colmap_recorder	colmap	Vivotek (+ optional Blackfly) COLMAP bag
pi/lidar	foxglove	foxglove	optional bridge
laptop	playback / monitor / analysis	matching	UI / reprocess

Frame / topic defaults

Item	Default
Blackfly image	/blackfly/image_raw (CAMERA_IMAGE_TOPIC)
Vivotek L/R	`/vivotek/left
OpenVINS odom	/ov_msckf/odomimu
Odom frame_id	global (OV_ODOM_FRAME_ID)
Lidar scan	/scan
Live clocks	synchronized system time; use_sim_time=false
Bag playback	use_sim_time=true + --clock

Calibration

1. Kalibr cam–IMU on Blackfly + IMU (VIO path).
2. Fill shared/config/openvins/kalibr_*.yaml templates (or drop files in shared/calib/).
3. Publish real CameraInfo for Blackfly (RTABMAP RGB if used).
4. Vivotek intrinsics/extrinsics separately for COLMAP / CloudCompare alignment.

Migration notes (from VINS-Fusion ARGOS)

• Front-end is OpenVINS (ov_msckf / run_subscribe_msckf), not vins_node.
• Pi image no longer builds Ceres-from-source or VINS-Fusion; RTABMAP is not baked into the VIO Pi image (native host install on the mapping Pi).
• Preferred mapper moved to Pi A (lidar); VIO path kept as alternative.
• Env: VINS_* → OV_*; odom default /ov_msckf/odomimu; peers split into PI_LIDAR_IP + PI_VIO_IP.
• Layout split for sparse-checkout: shared/ + pi/{vio,lidar}/ + laptop/.

Offline tools (host laptop)

sudo apt install colmap cloudcompare   # availability varies

See laptop/README.md for COLMAP + CloudCompare workflow.

License

MIT for ARGOS wrappers and configs. OpenVINS is GPLv3 — see LICENSE.