knowrob_designator

Work in Progress

This package is under active development and not yet stable. Interfaces, functionality, and structure may change frequently.

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Overview

The knowrob_designator package provides a ROS action interface for logging structured semantic data — called designators — into the KnowRob knowledge base.

A designator is a nested symbolic description (e.g., of actions, goals, objects) expressed as a JSON structure. This structure is parsed into RDF-style triples and submitted to KnowRob using its tell interface.

For a detailed description of the interfaces, see the Action Interface Description

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Package Structure

knowrob_designator/
├── action/
│   └── LogDesignator.action           # Action definition for logging designators
├── CMakeLists.txt                     # Build configuration
├── Dockerfile                         # Container setup (ROS + KnowRob)
├── launch/
│   └── knowrob_designator_service.launch  # Launches KnowRob and the action server
├── package.xml                        # ROS package metadata
├── README.md                          # You are here
├── run_knowrob_designator.sh          # Optional helper script (not required)
├── src/
│   ├── knowrob_designator/            # Library for the action server
│   │   ├── designator_parser.py         # Parses JSON designators into triples
│   │   └── __init__.py                  # Python package initialization
├── scripts/
│   ├── designator_parser.py           # Parses JSON designators into triples (no ROS dependency)
│   ├── knowrob_designator_client.py   # Example client that sends a test designator
│   └── knowrob_designator_service.py  # Action server that logs designators to KnowRob
├── setup.py                           # Python package setup
└── srv/                               # (empty, safe to delete or populate if needed)

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Running the System via Docker

This section describes how to launch the full system in a Dockerized environment.

Start the KnowRob and Designator Action Server

docker run -it --entrypoint bash knowrob_designator:latest
# Inside container:
root@<container_id>:/catkin_ws# roslaunch knowrob_designator knowrob_designator_service.launch

This will:

• Launch KnowRob with predefined settings
• Start the knowrob_designator_service.py action server

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In a second terminal: Run the Designator Client

Open a new terminal and run:

docker exec -it <your_container_name> bash
# Inside container:
root@<container_id>:/catkin_ws# rosrun knowrob_designator knowrob_designator_client.py

This runs a simple client that sends a test designator to the action server. The designator is NOT parsed at the moment and not expected to be valid.

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Dependencies

• ROS (Noetic recommended)
• KnowRob (knowrob/knowrob Docker image)
• knowrob_ros action interface