opd_version: 0.4.0 product: Plus One category: [agent-device, consumer-electronics, battery-powered, wireless, open-hardware] maker: N+1 Labs maker_endorsed: true synthetic: true revision_examined: Plus One Core, generation one, concept rev B (decision 20; prototype in design, nothing built) units_examined: 0 license: CC-BY-4.0 trust_level: draft layers: [parts, electronics, bom, process, line, risk, sim, variants, device-model (draft)]
Plus One
Prototype in design. Every value is a design target or a design choice. Nothing has been built, measured or simulated against a real build. Don't use these numbers to make decisions about cost or yield.
Summary
An open agent puck, phone-ring size: about 57 mm across and 9.5 mm thick. You hold the plus to talk to your agent; the light ring shows when an agent needs you. An ESP32-S3 module with 16 MB flash and 8 MB PSRAM runs it, with two mics, a speaker behind a capped amp, a haptic motor, a motion sensor and a rechargeable Li-ion cell behind hardware protection.
The base is the interface, and nothing ships attached. A magnet ring makes it stick wherever a phone goes; it works with magnetic phone mounts and chargers. Three twist-lock lugs inside the rim carry the load for clips and lanyards. An alignment key and five pogo pads take a dock or an electronic module. It charges by USB-C, the dock, or a magnetic wireless charger; a phone can't charge it.
Unlocked by design. USB-C and a BOOT button reach the ROM bootloader, which can't be overwritten, so any unit can be reflashed.
Editions
| Edition | What it is | Status |
|---|---|---|
| Plus One | Core, as above | In design |
| Plus One+ | Same board, more parts fitted: light sensor, NFC, debug jumper, clear shell | Coming next |
| Plus One++ | Plus One+ boxed with a set of backs | Coming next |
A wearable generation two, about 40 to 44 mm, comes later with the same firmware and pad pinout. It isn't in this OPD.
The line
Eight stations of final assembly, test and pack. The main board is bought in assembled. S6 now bonds the magnet ring and places the coil and pads before closing the base. S8 (functional test, mark, pack) is the slowest at 56 s against a 60 s takt. The Plus One+ checks would push it to 62 s, so splitting S8 is the recommended variant. All times are target estimates.
What's not known yet
- No unit exists, so nothing is measured. Every claim is
inferredat low confidence. - Thickness. 9.5 mm is the top of the 8 to 9.5 mm target. The 3.5 mm cell and the 3.1 mm module set it; 8 mm needs a thinner cell or the chip on the board instead of a module.
- The magnet ring. Its exact size and polarity haven't been checked against the Wireless Power Consortium spec. Whether to certify for the Qi2 name is open; until then nothing claims it.
- Battery. About 150 mAh in a 28 x 16 x 3.5 mm cell (target). Battery life is not modelled. The EU's replaceable-battery rule from February 2027 against a cell sealed in the core is an open question.
- Costs are not quoted. The BOM has no prices.
- The yield model hasn't been run on Plus One.
- Audio, Wi-Fi range and wireless charging are not modelled.
- The firmware simulator for the ESP32-S3 isn't chosen yet (see
device/model.yaml).
Layers and files
| Layer | Files |
|---|---|
| Everything, machine-readable | opd.yaml |
| Parts and 3D | parts/*.step, parts/*.glb, parts/geometry.json, model/*.glb, sim/scene.usda |
| Electronics | electronics/board.yaml |
| BOM | bom/bom.csv (no prices yet) |
| Process | process/routing.csv |
| Line | line/layout.usda, line/layout.glb, line/sops/S1.md to S8.md, line/test-plan.yaml, line/sampling.yaml, line/control-plan.csv |
| Risk | risk/pfmea.csv |
| Simulation inputs | sim/mc-inputs.yaml (assumptions for the yield model) |
| Device model, draft | device/model.yaml (proposal 0001) |
| Design brief, with the thickness stack-up | docs/design-brief.md |
| Accessories | accessories/README.md, accessories/interface.yaml (the base as an interface), accessories/catalog.yaml, accessories/cad/ (fit gauge, flat back, steel ring), accessories/template/mating_half.py |
Cite, changes and contacts
Cite as: Plus One, OPD 0.4.0, N+1 Labs, Open Product, 2026. Changes: CHANGELOG.md.