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A GpsDriver decodes a position-fix stream from a u-blox, NMEA, RTK, or vendor-custom receiver and exposes it as a series of GpsFix samples. Drivers that support RTK can also accept RTCM correction payloads.

​
The interface

from ados.sdk.drivers.gps import (
    GpsDriver,
    GpsCandidate,
    GpsCapabilities,
    GpsSession,
    GpsFix,
)

class MyGpsDriver(GpsDriver):
    async def discover(self) -> list[GpsCandidate]:
        ...

    async def open(self, candidate, config) -> GpsSession:
        ...

    async def close(self, session) -> None:
        ...

    def capabilities(self, session) -> GpsCapabilities:
        ...

    async def fix_iterator(self, session):
        # async generator yielding GpsFix
        ...

    async def inject_rtcm(self, session, payload: bytes) -> None:
        ...
inject_rtcm is a no-op for non-RTK drivers.

​
Capabilities

GpsCapabilities(
    protocol="ubx",
    constellations=["GPS", "GLONASS", "Galileo", "BeiDou"],
    max_update_hz=10.0,
    supports_rtk=True,
    supports_dual_band=False,
    supports_heading=False,
)

​
Fix samples

GpsFix(
    timestamp_ns=ns,
    latitude_deg=12.97,
    longitude_deg=77.59,
    altitude_msl_m=920.0,
    fix_type=3,
    satellites_used=14,
    hdop=0.9,
    vdop=1.4,
    speed_mps=0.0,
    heading_deg=None,
)
fix_type follows the common convention: 0 no fix, 2 2D, 3 3D, 4 DGPS, 5 RTK float, 6 RTK fixed.

​
Manifest permissions

agent:
  permissions:
    - sensor.gps.register
    - serial.read_write
    - mavlink.gps_inject       # only if the driver forwards RTCM to the FC

​
See also