Source: https://guthlabs.ai/docs/instruments/plate-motion-rate-distance-projector/implementation/

instrument implementation / implementation-contract

# Plate Motion Rate & Distance Projector implementation

A source-bound implementation contract for Plate Motion Rate & Distance Projector; deployment and executable qualification remain separate.

Status: **VERIFIED_CLEAN**Lifecycle: **implementation-contract**

## Binding contract

This record describes what an executable surface must bind and validate. It does not claim that a public calculator, package, or production route is deployed.

**Record owner**: Guth Instruments

**Lifecycle**: verified-clean

**Evidence ID**: t7-096

**Effect**: Computation or source lookup only

## Input and validation requirements

The inverse time operation is undefined for zero rate and must reject distance=100 cm with rate=0 cm/yr. A second hazard is the unclarified treatment of negative custom rates, which can produce either signed displacement or an invalid input depending on the UI convention.

## Required corrections

No binding erratum is attached to this unique-name record. Implementers must still preserve the declared units, domain, and failure behavior.

## Inspectable interface fixture

The sample below is evidence for interface and validation tests, not a production implementation.

````
{
  "inputs": {
    "operation": "distance",
    "rate": 1,
    "rate_unit": "cm/yr",
    "time": 365.25,
    "time_unit": "Julian years",
    "plate": "custom"
  },
  "expected_outputs": {
    "distance_cm": 365.25,
    "distance_m": 3.6525,
    "distance_km": 0.0036525
  },
  "reference_data": {
    "custom_rate_cm_per_year": 1,
    "source_convention": "User-specified custom rate; 1 cm/yr is a realistic slow plate-motion magnitude",
    "julian_year_days": 365.25,
    "julian_year_source_convention": "IAU standard Julian year, exact convention",
    "centimeters_per_meter": 100,
    "kilometers_to_centimeters": 100000,
    "length_conversion_source_convention": "SI decimal-prefix definitions, exact"
  },
  "working": "d = rate × time = 1.0 cm/yr × 365.25 yr = 365.25 cm. Convert to meters: 365.25 cm ÷ 100 cm/m = 3.6525 m. Convert to kilometers: 3.6525 m ÷ 1000 m/km = 0.0036525 km. The 365.25-day Julian-year table entry is exact, although the calculation cancels the year unit directly."
}
````

## Other records

[01**Overview**](<https://guthlabs.ai/docs/instruments/plate-motion-rate-distance-projector/>)[02**Mechanism**](<https://guthlabs.ai/docs/instruments/plate-motion-rate-distance-projector/mechanism/>)[04**Qualification**](<https://guthlabs.ai/docs/instruments/plate-motion-rate-distance-projector/qualification/>)

## Sources and evidence

These pointers bind the page to evidence. They do not grant authority or collapse verification into deployment.

- `VERIFIED_LEDGER.json`

- `evidence-tranche7/tranche7-results.json`