Emet

A companion-robot engine that discovers whatever body it finds itself in.

Write a personality once. Run it on a robot with a head, wheels, and glowing eyes, or on a Raspberry Pi with nothing but a speaker. The same personality, the same memories, and a robot that knows the difference and will tell you about it.

Emet (Hebrew אמת, "truth") is the word inscribed on the golem's forehead to bring it to life; erase the first letter and it reads met, "death". The name is a promise: the thing you are talking to is honest about what it is.

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Status: 0.2 (early)

Emet does not yet listen, speak, remember, or move. Nothing here drives a servo.

What it does today is answer one question: given a robot, what would each intent mean on it? That question turns out to be the whole product in miniature.

$ emet explain examples/bodiless.yaml
BINDING TABLE  —  examples/bodiless.yaml   (body: bodiless)
0 capabilities, 31 intents, 0 bound to hardware, 31 to voice

    express.curiosity  voice   inflect   preset=rising filler=['hm?', 'hmm.']

$ emet explain examples/mock-scout.yaml
BINDING TABLE  —  examples/mock-scout.yaml   (body: mock_scout)
5 capabilities, 31 intents, 30 bound to hardware, 1 to voice

    express.curiosity  head    tilt      angle_deg=12 speed=0.4 hold_ms=700

Same personality, same configuration, two bodies. Nobody wrote an if statement.

How it works

A personality emits intents: about thirty things it might want, like express.curiosity or attend.speaker. It never names hardware; that is what makes it portable.

Each intent has a chain: a ladder of ways to perform it, best first.

express.curiosity:
  rungs:
    - actuator: {role: head, axis: pitch}     # tilt your head
      action: tilt
    - actuator: {role: eyes}                  # or squint
      action: expression
    - actuator: {role: ambient, type: light}  # or pulse a light
      action: pulse
    - actuator: {voice: true}                 # or just say "hm?"
      action: inflect

At boot, Emet walks each ladder against the robot it is actually running on and binds the first rung that fits.

Every chain must end in a voice rung, and the validator refuses to load one that does not. Since every Emet robot is required to have a speaker, the last rung can never fail, which turns "no intent can fail for lack of hardware" from a promise someone has to remember into something the software enforces.

Try it

python -m venv .venv
.venv/bin/pip install -e "emet-sdk[dev]" -e "emet-hal[dev]"   # Windows: .venv\Scripts\pip

cd emet-sdk
emet validate examples/mock-scout.yaml --verify-drivers
emet explain  examples/scout-01.yaml --why

--why is the one to remember. When a robot is not doing what you expected, it tells you which rungs were skipped and what was wrong with each:

  ~ express.affection  eyes  expression  hold_ms=1500 preset=soft
      skipped rung 0 {role: head, axis: roll}: 'head' has no 'roll' axis; it has pitch, yaw

Layout

emet-sdk/	Types, schemas, the intent vocabulary, chain resolution. The contract everything agrees on.
emet-hal/	Drivers and locomotion plugins. Where hardware support goes.
emet-engine/	Personality, memory, arbitration. Does not exist yet.

Documentation

• DESIGN.md: the specification. Manifest format, intent vocabulary, memory model, plugin contract, and why each decision went the way it did.
• CONTRIBUTING.md: what is open to contribution, the design rules that are not negotiable, and how to run what CI runs.
• TRADEMARK.md: the code is yours to fork; the name is not.

Licence

Apache 2.0 throughout: SDK, HAL, and engine alike. Fork it, ship it, sell it.

The name is the deliberate exception. A permissive licence means anyone may fork Emet and close their fork, so the mark is the only thing keeping "I run Emet" meaningful. See TRADEMARK.md.