# QERRA-v2 Classical — Explainable Ethical Scoring Engine with ROS 2 Bridge (open for feedback)

**URL:** https://discourse.openrobotics.org/t/qerra-v2-classical-explainable-ethical-scoring-engine-with-ros-2-bridge-open-for-feedback/54904
**Category:** ROS General
**Tags:** ros2
**Created:** [May 16, 2026, 8:01am UTC](https://discourse.openrobotics.org/t/qerra-v2-classical-explainable-ethical-scoring-engine-with-ros-2-bridge-open-for-feedback/54904 "2026-05-16T08:01:49Z")
**Posts on this page:** 1
**Page:** 1

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### Author: ![marunigno-ship-it](https://sea2.discourse-cdn.com/flex022/user_avatar/discourse.openrobotics.org/marunigno-ship-it/32/34877_2.png) [@marunigno-ship-it](https://discourse.openrobotics.org/u/marunigno-ship-it)
#### Post date: [May 16, 2026, 8:01am UTC](https://discourse.openrobotics.org/t/qerra-v2-classical-explainable-ethical-scoring-engine-with-ros-2-bridge-open-for-feedback/54904/1 "2026-05-16T08:01:49Z")

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Hi everyone,

I’ve built QERRA-v2 Classical — a 100% classical, fully explainable ethical evaluation engine based on 12 immutable human-centred vectors (SEMEV-12). It returns traceable scores + reasoning with no neural networks.

The repo includes a ready-to-use ROS 2 bridge (ros2\_bridge.py) that runs standalone or as a full node (subscribes to /qerra/situation\_input, publishes score, decision, and full SEMEV-12 result).

Live API + full documentation:

> **[GitHub - marunigno-ship-it/QERRA-v2-classical: 100% Classical Ethical Decision Framework –...](https://github.com/marunigno-ship-it/QERRA-v2-classical)**
>
> 100% Classical Ethical Decision Framework – Extension of QERRA-v2 Hybrid

I would be very grateful for any feedback, especially:

1. Does the topic structure and message types fit typical robotics pipelines?
2. What would make the bridge more useful in real Behaviour Trees?

Happy to adapt based on real use cases.

Thank you!