The cphi-Chronos is a self-contained, air-gapped wrist instrument for lunar and tidal prediction. It bridges mechanical engineering and low-power digital computation to serve as a deterministic "Reference-Grade Instrument". No GPS or network required.
| Subsystem | Status |
|---|---|
| Mechanical Core | Specification Defined / Seeking CAD |
| Tide Engine | Functional (C++) |
| Logic Board | Schematic Draft / Seeking PCB Layout |
| Case Design | Conceptual (Dimensions Set) |
A hybrid mechanical-electronic wrist instrument for lunar phase and tidal prediction.
The cphi-Chronos is a fully self-contained system. It operates without GPS, network access, or external services. All calculations are performed locally using deterministic physical and mathematical models.
- Movement: Seiko NH35 automatic movement
- Complication: Custom 135-tooth gear train
- Cycle: Tracks the lunar synodic cycle (29.53059 days)
- Autonomy: Operates without electricity
- MCU: ESP32-C3 (or ATTiny alternative)
- Display: 1.02" SPI E-Ink (GDEW0102I6F)
- RTC: DS3231 (±2 ppm, temperature compensated)
- Power: CR2032 coin cell
- Function: Local tidal prediction and visualization
[ NH35 Movement ] --> [ Gear Train ] --> [ Moon Disc ][ CR2032 ] --> [ MCU ] <--> [ RTC ] --> [ E-Ink Display ]
- Mechanical and electronic systems are fully decoupled
- Timekeeping remains functional without power
- Tidal logic depends only on RTC and stored constants
- Case: Grade 2 Titanium (CNC)
- Crystal: Domed sapphire, AR-coated
- Diameter: 42 mm
- Thickness: 12 mm
- Water Resistance: Target 50 m (requires gasket validation)
- Interface: Mechanical crown + Internal USB-C header
Refresh interval: Every 10 minutes
Current implementation: ~9–12 months on a single CR2032
Target: 18+ months (optimized firmware)
| Component | Active | Sleep |
|---|---|---|
| MCU | ~15 mA | ~10 uA |
| E-Ink | ~20 mA (refresh) | 0 |
| RTC | ~3 uA | ~3 uA |
- Lunar Drift: <1 day per 122 years (135-tooth gearing)
- Tide Model: 5-constituent harmonic analysis (M2, S2, N2, K1, O1)
- Tide Accuracy: ±10–20% depending on location
- Connectivity: None (air-gapped by design)
- /hardware → STEP files, PCB, BOM
- /firmware → Tide engine, display drivers
- /validation → NOAA comparison scripts and power models
- /docs → Architecture, calibration, physics, philosophy