Goddard — Core Functions

Mission

Help elderly people live independently and safely at home. This is the non-negotiable priority above every other design goal. Hardware choices, voice, form factor, skill prioritization, safety rules — all of it flows from this mission. When two designs are otherwise equal, pick the one that a 75-year-old living alone would trust more.

Reflex loop

Goddard runs two loops simultaneously:

10 Hz main loop — proprioception, battery and thermal monitoring, safety flag evaluation, intent queue drain, and firing of owned_by: goddard skills (movement, power, sensing). This is the heartbeat of the robot. At each tick it checks: is anything wrong? is there an intent to act on? do the safety flags permit acting?

100 Hz balance sub-loop — dedicated to leg control. Faster than the main loop because stability can’t wait. The sub-loop feeds into the main loop’s state but runs on its own cadence.

Target hardware: Raspberry Pi 5 or Jetson Orin Nano class SBC. These numbers are achievable on real hardware today. 10 Hz main and 100 Hz balance sub-loop are both well within reach. We’re not speculating about future silicon — we’re designing to what exists.

Safety monitor

The safety monitor lives in core and runs on every reflex tick. It has three powers:

  1. Pre-call precondition check. Before any skill fires, the safety monitor evaluates the skill’s preconditions: block. If a condition fails, the call is refused and Goddard reports why. No exceptions.

  2. Mid-call interrupt. While a skill is running, the safety monitor watches for flag changes. If a flag trips (obstacle appears, thermal limit exceeded, voice command received), the monitor aborts the running skill and transitions to the safe state.

  3. Hard stop. Emergency halt: Goddard drops to safe pose immediately. Triggered by a fall-detection event, a panic button, or an unrecoverable safety flag. Motion stops before anything else.

Elderly-care rules (non-negotiable):

  • No fast motion near humans. Speed caps when any person is within range.
  • Thermal limits enforced. No surface accessible to touch may exceed safe skin-contact temperature.
  • Voice-interruptible always. Any spoken command can halt or redirect Goddard mid-action. The person is always in control.
  • Obstacle-aware for walkers and canes. Goddard’s path planning must account for mobility aids — not just the person, but their equipment.
  • Never expose hot surfaces within human reach. The 3D printer nozzle cools before any proximate motion. No open flame. No exposed heating elements.

Skill registry

At boot, Goddard file-scans data/robots/organs/ and builds the registry from every YAML manifest it finds. The registry is the planner’s menu of callable skills.

Hot-reload is a v2 feature. We’re not implementing it now. But the schema is designed to tolerate it: every manifest has a stable id and will eventually carry a version field. Adding hot-reload later doesn’t require changing the schema, just adding a file-watcher.

The registry is just a directory of YAML manifests. No database. No service. A file-scan at boot, loaded into memory. Simple enough to reason about, robust enough to ship.

The skill-directory priority tiers (see docs/goddard/SKILL-DIRECTORY.md) give the planner an ordering hint — embedded skills first, stored tools last — but the registry itself doesn’t enforce tiers. That’s the planner’s job.

Owned-by boundaries

Every manifest declares owned_by: goddard or owned_by: jarvis.

  • goddard (reflex) owns: movement, power, sensing. These run on the 10 Hz main loop and 100 Hz balance sub-loop. The reflex loop fires them directly without planner mediation.

  • jarvis (planner) owns: manipulation, fabrication, communication, gadgets, sequence_reading. These are intent-driven and mediated through the planner’s intent queue.

“Jarvis” is a subsystem name, not a separate persona. Internally, there is no “Jarvis” character — it’s a label for the planner subsystem of Goddard. One robot, one voice. The distinction is purely architectural: which loop fires the skill.

Aesthetic

90s translucent plastic. iMac G3, Gameboy Color, Tamagotchi. Colorful, see-through, approachable, friendly to anyone who grew up before all tech went matte-black. Nothing about Goddard looks tactical, military, or intimidating.

This is not incidental. The chassis aesthetic is part of the elderly-care mission. A robot that looks like a weapon — or a spider, or a spy device — has failed before it enters the room. Goddard should look like something a person would be glad to see when they wake up alone.