Acoustic Vehicle Alert Systems [AVAS] for EVs

It moves past the toy phase quickly and gets into how AVAS behaves in real vehicles. The UNECE R138 section, especially the 0–20 km/h speed ramp audio clip comparison, stuck and felt concrete. Enough context to talk with suppliers and sanity-check specs in PRs; you don't need a repo or fancy infra to follow. I wasn't sold on the short psychoacoustics bit and wished there was more on in-vehicle testing, but it's a handy add to the toolkit.

Came in checking how this handles scale beyond a pilot, especially once AVAS has to ship across trims and markets. The UNECE R138 section stuck, particularly the table walking speed bands and the example where the sweep shifts under 20 km/h; that’s something I’ll paste into a PR comment. It's beginner-level and mostly clear, though I wasn't sold on the mic placement advice without more obs data from road tests. Probably reopening this ahead of our next arch review.

The scaling angle grabbed me, since AVAS gets messy once you’re shipping across trims and markets. Chapter 3’s UNECE R138 pass/fail walkthrough—especially the 20 km/h sweep and frequency band checks—stuck because it mirrors what I’ve seen fail late in prod. It ties system arch to infra and obs in a practical way, from sensor inputs to how alerts behave under CI updates in the repo. I wasn’t sold on the psychoacoustics bit, but it nudged how I troubleshoot end‑to‑end when something sounds off.