Proposal: URML (substrate-neutral robot intent) cross-citation for YARP — alternate-substrate middleware sibling to URML's ros2-runtime

[idoco2003]

Hi @robotology YARP team,

Proposing a URML v0.1 capability-manifest cross-citation for YARP over robotology/yarp. URML (Universal Robot Language, Apache-2.0) is an open spec for substrate-neutral robot intent.

URML's substrate-neutral claim depends on declaring more than one substrate. URML's existing reference/ros2-runtime/ targets ROS 2; YARP is the sibling middleware that makes URML's substrate-neutrality concrete in the manifest. Medical-research / European-research deployments (including iCub, engaged separately) often use YARP rather than ROS 2; URML's manifest needs to declare these substrates cleanly.

LGPL is the gating fact for adapter shape — URML's Apache-2.0 adapter pattern composes with LGPL middleware at the API boundary without modifying YARP, which is LGPL-compatible posture. Cross-citation framing recommended pending substrate-license-class Spec RFC.

This is proposal-only, posted as part of URML's Move #15 outreach (5 engageable RFCs in this wave).

Full RFC: https://github.com/URML-MARS/URML/blob/main/docs/rfcs/0194-iit-yarp-outreach.md

Questions worth robotology YARP maintainer input on:

1. Alternate-substrate middleware manifest declaration. URML's v0.1 has no substrate.middleware: yarp declaration. Spec RFC queued. Manifest field expectations from the YARP perspective (version, transport class, port naming convention)?
2. LGPL substrate license-class declaration. Should URML's manifest declare LGPL-linkable substrate as a first-class field for downstream operator awareness?
3. YARP↔ROS-2 bridging declaration. Some deployments bridge between YARP and ROS 2; manifest field for declaring bridging topology?
4. Bridge home. Cross-citation only (recommended pending LGPL framing), URML repo (reference/yarp-runtime/), or IIT-maintained robotology/yarp-urml-bridge?
5. Conformance listing. Would IIT consider a README link to URML's compatible-runtimes registry once a working cross-citation ships?
6. Anything else.

Ido Yahalomi (URML maintainer, urml.dev, greenvh@gmail.com)

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AI-assisted prose, maintainer-reviewed before posting (see VIBE.md). Human-only correspondence available on request.