README

Labclean package

Autonomous lab-cleaning application for the Mirte robot, built on py_trees_ros. The package provides a behaviour tree that coordinates exploration, object detection, arm manipulation, and coverage navigation to clean a lab environment without human intervention.

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Run

Start the full bringup stack (behaviour tree + Nav2 + MoveIt + perception pipeline):

ros2 launch mirte_lc_labclean labclean_bringup.launch.py use_sim_time:=false

Individual nodes can also be run directly:

ros2 run mirte_lc_labclean labclean_tree
ros2 run mirte_lc_labclean labclean_manager
ros2 run mirte_lc_labclean test_node

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Nodes

labclean_tree

The main py_trees_ros behaviour tree. Ticks at 500 ms and drives the full task loop.

Subscribed topics

Topic	Type	Description
/explore/status	explore_lite_msgs/ExploreStatus	Frontier exploration state
/dashboard/cancel	std_msgs/Empty	Cancel button event
/dashboard/start	std_msgs/Empty	Start button event
/io/power/power_watcher	battery msg	Battery state for low-battery detection
/perception/depth/detected_objects	mirte_lc_msgs/DetectedObjectArray	3-D (cloud) detections from depth perception pipeline

Published topics

Topic	Type	Description
/io/leds/leds/set_color (service)	mirte_msgs/SetNeopixel	LED strip colour
/labclean_led_markers	visualization_msgs/Marker	LED colour visualisation in RViz

Action clients

Action server	Type	Used by
/navigate_to_pose	nav2_msgs/NavigateToPose	NavigateToPosition behaviour
/arm_controller/move_to_position	mirte_lc_msgs/MoveToPosition	MoveArm behaviour
/move_to_position	mirte_lc_msgs/MoveToPosition	PickObject behaviour
/labclean_navigator/coverage	mirte_lc_msgs/NavigateCoverage	CoverageTask behaviour

Service clients

Service	Type	Used by
/labclean_navigator/set_state	mirte_lc_msgs/ServeCoverageStatus	SetCoverageStatus behaviour
/perception/planar/get_detected_objects	mirte_lc_msgs/GetDetectedObjects	GetPlanarObjects behaviour

Blackboard variables

Key	Type	Description
cloud_objects_detected	list[DetectedObject]	Latest detections from depth camera
num_cloud_objects_detected	int	Count of depth-camera detections
planar_objects_detected	list[DetectedObject]	Detections from planar perception service
planar_objects_detected_bool	bool	Set to True when planar objects are available
explore_status	str	Latest exploration state string
cancel_button	event	Set when cancel is pressed
start_button	event	Set when start is pressed
battery_low_warning	bool	Set by battery monitor when charge is below 25 %

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Behaviour tree structure

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Behaviours

FlashLedStrip

Sends a colour command to the Neopixel LED strip via the /io/leds/leds/set_color service and publishes a flat Marker cube above the map origin for RViz visualisation. Always returns SUCCESS after one tick.

behaviours.FlashLedStrip(name="Flash Red", colour=[1.0, 0.0, 0.0])

Note: The hardware LED channel mapping is swapped relative to the message field names (r→blue, g→red, b→green). The behaviour compensates for this internally.

SetCoverageStatus

Calls /labclean_navigator/set_state to pause, resume, or stop the coverage navigator. Returns RUNNING until the service responds, then SUCCESS or FAILURE.

behaviours.SetCoverageStatus(name="Pause Coverage", requested_status="pause")
# requested_status: "pause" | "resume" | "stop"

NavigateToPosition

Navigates the robot to a goal pose using Nav2’s BasicNavigator. The target can be a fixed map coordinate or the closest object read from the blackboard.

# Fixed target
behaviours.NavigateToPosition(name="Dock Action", target_position=[0.0, 0.0])

# Closest object from blackboard
behaviours.NavigateToPosition(name="Approach", blackboard_key="cloud_objects_detected")

Returns SUCCESS when the robot is within 0.5 m of the goal, FAILURE if navigation fails or if no progress is made for 15 s, and RUNNING otherwise.

MoveArm

Sends a goal to /move_to_position. Accepts a named pose, a blackboard pose, or an explicit (x, y, z) position.

behaviours.MoveArm(name="Deploy Arm", predefined_pose="standby")
behaviours.MoveArm(name="Place", predefined_pose="place_right")

PickObject

Executes a seven-step pick-and-place sequence against the /move_to_position action server:

Step	Action
approach	Move wrist above closest detected object
open	Open gripper
dive	Lower wrist to object
grip	Close gripper
place	Move to place_left (target) or place_right (non-target)
let_go	Open gripper
standby	Return arm to vigilant pose

The closest object is selected by Euclidean distance from base_link. Returns FAILURE if any step is rejected or if no objects are available.

CoverageTask

Sends a coverage goal with planner_type = SKELETON by default to /labclean_navigator/coverage and monitors the action until completion.

GetPlanarObjects

Calls /perception/planar/get_detected_objects and writes results to the blackboard. Returns FAILURE if no objects are detected (used with Retry to poll up to 5×).

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Useful CLI commands

# Render the behaviour tree structure as a dot graph
py-trees-render -b mirte_lc_labclean.labclean_tree.create_root

# Watch all blackboard variables live
py-trees-blackboard-watcher --list

# Watch a specific blackboard variable
py-trees-blackboard-watcher /battery.percentage

# Open the graphical tree viewer
py-trees-tree-viewer --no-sandbox

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Configuration

File	Purpose
config/labclean.rviz	RViz layout including LED marker, costmaps, and arm displays
config/octomap.yaml	OctoMap parameters for the 3-D obstacle layer

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Dependencies

• py_trees / py_trees_ros

• nav2_simple_commander, nav2_msgs

• mirte_msgs, mirte_lc_msgs

• explore_lite_msgs

• tf2_ros

• visualization_msgs, geometry_msgs, action_msgs