Interface and Orchestration¶

After the Isaac USD scene is up, datagen does not call OCS2 or Nav2 servers from Python by name. YAML task_queue blocks resolve to registered skills; skills emit StageTarget sequences and send them through ROS2RobotInterface.

APIs below are from robot_action_composer @ feature/dex-grasp-generator and its docs/. YAML skill: values are registered names from that README (not a Python ActionSequence / actions.MoveJ class).

ros2_robot_interface (motion and recording)¶

Repository: fiveages-sim/ros2_robot_interface

Composer’s README: the pure motion / queue path depends on ROS2RobotInterface (ctx.interface), not LeRobot’s ROS2Robot class. Recording still moves the robot through that same interface; the LeRobot plugin is only the episode writer (next page).

Typical install is the lerobot_ros2 script, not a one-off pip on system Python:

cd lerobot_ros2
./init.sh all-motion    # ros2_robot_interface + robot_action_composer

Reference: ros2_robot_interface, Python Interface how-to.

robot_action_composer (task_queue + skills)¶

Branch: feature/dex-grasp-generator

In the lerobot_ros2 monorepo this package is submodules/robot_action_composer. Two layers:

Layer	Job
`motion_generation`	Geometry → `StageTarget` / `ArmTarget` sequences; `execute_stage_sequence` calls `ROS2RobotInterface` (Cartesian, dual-arm, MoveJ, gripper timing).
`task_runtime`	`runner.run_task_queue`: connect → FSM → optional Isaac reset → each YAML block → `get_skill` → execute. Unknown `skill:` names raise `KeyError` with the registered list.

YAML lives under robots/<Robot>/task_configs/**/*.yaml (optional vendor grouping robots/<Vendor>/<Robot>/). Discovery, merge rules, and robot.yaml: TASK_CONFIG_YAML.md, ROBOT_CONFIG.md.

Skill names (examples from the README index; parameters in SKILLS_REFERENCE.md):

Category	Registered `skill:` names
Single arm	`single_arm.pick`, `single_arm.place`, `single_arm.move_to_pose`, `single_arm.move_relative`, `single_arm.move_to_object`, `single_arm.goto_cache_pose`, `single_arm.drawer.pull_open`, `single_arm.drawer.close_push`
Dual arm	`dual_arm.carry`, `dual_arm.parallel_pick`, `dual_arm.handover`, `dual_arm.place`, `dual_arm.bimanual_align`, `dual_arm.goto_cache_pose`
Navigation	`nav.navigate_to_pose`, `nav.navigate_to_object`, `nav.navigate_relative`, `nav.send_nav_goal`, `nav.wait_nav_arrived`
Joint / session / env	`joint.movej_to_config`, `joint.goto_cached_joints`, `robot.cache_ee_pose`, `robot.send_mode_command`, `env.randomize_object_local_xyz`, …

Datagen workspace used in the README is examples/IsaacSim inside lerobot_ros2 (contains robots/). Robot-specific notes, including wheeled-arm FiveAges W2 dual-arm tasks, are next to those trees (e.g. robots/FiveAges_W2/README.md).

Official Nav2, not a custom nav stack¶

Composer does not implement Nav2 servers. nav.* skills wrap ROS2RobotInterface’s Nav2 client API. Scene-level launch is separate from the task YAML.

From docs/ROS2_STACK.md:

Do not put ros2_stack inside task-queue YAML.
Merge: robot.yaml → ros2_stack: then leaf .meta/ros2_stack.yaml.
Motion presets: ocs2-fullbody / ocs2-split-body / ocs2-demo (ocs2_arm_controller launches).
Navigation: navigation.profile default or map_only expands to nav2_profile:=…. Default launch: robot_common_launch / navigation/navigation_isaac_gt.launch.py (file exists on that repo’s main; see robot-descriptions-common).
navigation.required: auto starts Nav2 only when the task_queue contains nav.* skills.

That is the official Nav2 install/launch already used by the robot workspace, not a fiveages-specific planner.

CLIs (after `./init.sh`)¶

Console scripts from composer pyproject.toml: motion-generation, ros2-stack, grasp-generation, check-isaac-pose, check-robot-status.

Run from a directory that contains robots/ (usually examples/IsaacSim):

cd examples/IsaacSim

# Scene-level OCS2 + Nav2 (background logs under .ros2_stack/<robot>/)
ros2-stack --lang zh launch
ros2-stack status
ros2-stack stop

# Task queue (dry motion; optional --ensure-ros2-stack)
motion-generation
motion-generation --robot dobot_cr5 --task-key pick_place --scene default
motion-generation --robot fiveages_w2 --task-key transfer_blade --ensure-ros2-stack

grasp-generation serve … is an optional grasp-setup UI on this branch (GRASP_GENERATION.md); it is not the recording entry and is not ros2-viser.

Isaac entity pose / joint dump helpers (check-isaac-pose, check-robot-status) need the sim and /get_entity_state as documented in the composer README.

Full CLI flag lists: robot_action_composer reference.

Next on the pipeline¶

Recording is an extra on top of this queue: same YAML task_queue, plus LeRobot plugins. Continue at LeRobot record and export.