Ground Station

Python interface (DJIInterface)

GroundStation/Python/lyrebird_groundstation/dji_client.py provides a high-level class wrapping all HTTP commands and the TCP telemetry socket in a thread-safe background receiver.

import time
from lyrebird_groundstation.dji_client import DJIInterface, discover_drone

# Auto-discovery via UDP broadcast (port 30000) if no IP provided
dji = DJIInterface("", discover_callback=discover_drone)

# Start background telemetry thread (TCP socket, port 8081)
dji.startTelemetryStream()

# Read latest telemetry (thread-safe, returns copy of last JSON snapshot)
print(dji.getBatteryLevel())          # int: 0–100
print(dji.getLocation())              # {'latitude': ..., 'longitude': ..., 'altitude': ...}
print(dji.getHeading())               # float: compass degrees
print(dji.getAttitude())              # {'pitch': ..., 'roll': ..., 'yaw': ...}
print(dji.getGimbalAttitude())        # {'pitch': ..., 'roll': ..., 'yaw': ...}
print(dji.getSatelliteCount())        # int
print(dji.getFlightMode())            # str: 'GPS', 'ATTI', 'VIRTUAL_STICK', 'GO_HOME', ...
print(dji.isManualOverrideActive())   # bool
print(dji.getRemainingFlightTime())   # int: seconds
print(dji.getDistanceToHome())        # float: metres
print(dji.getZoomRatio())             # float

# Commands
dji.requestSendTakeOff()
dji.requestSendLand()
dji.requestSendRTH()                  # Aborts mission first, then RTH
dji.requestSendEnableVirtualStick()
dji.requestAbortMission()             # Abort + disable Virtual Stick
dji.requestAbortDJINativeMission()    # Abort DJI native mission only

# Navigation
# Nose-forward: drone turns to face the leg, flies forward, then rotates to yaw on arrival.
dji.requestSendGoToWaypointNoseForward(49.306254, 4.593728, 20.0, yaw=90, speed=5.0)
# Hold-heading: nose stays on yaw for the whole flight (drone crabs sideways), tighter tolerance.
dji.requestSendGoToWaypointHoldHeading(49.306254, 4.593728, 20.0, yaw=90, speed=5.0)
dji.requestSendNavigateTrajectoryDJINative(
    [(49.306, 4.593, 20), (49.307, 4.594, 25), (49.308, 4.595, 20)], speed=10.0)
dji.requestSendGotoYaw(45.0)
dji.requestSendGotoAltitude(30.0)

# Camera / gimbal
dji.requestSendGimbalPitch(-30.0)
dji.requestSendGimbalYaw(45.0)
dji.requestSendGimbalRelPitch(-5.0)     # relative to the current angle
dji.requestSendGimbalRelYaw(10.0)
dji.requestSendZoomRatio(4.0)
dji.requestCameraStartRecording()
dji.requestCameraStopRecording()

# Thermal / payload
dji.requestCapture()                     # capture descriptor for the thermal lens
dji.requestCaptureTemperature()          # thermal max temperature
dji.requestLRFMeasure()                  # distance + geo-referenced target + laser state
dji.getLRFTarget()                       # last locked target from telemetry
dji.requestDrop()                        # release payload (airframes with a drop port)

# Media
files = dji.listMedia()                  # [{"name", "index", "size", "type"}, ...]
dji.downloadByName(files[0]["name"], out_dir="./media")

# Sequence-tracked commands — avoids acting on a stale reach flag
seq = dji.requestSendGoToWaypointNoseForward(49.306254, 4.593728, 20.0, yaw=90, speed=5.0)
while not dji.isWaypointReached(seq):
    time.sleep(0.1)

# Preflight
dji.isReadyToTakeoff()
dji.getTakeoffBlockReason()

# Manual override
dji.requestDeactivateManualOverride()

# RTH altitude
dji.requestSetRTHAltitude(50.0)

# Virtual stick (raw AVS, values saturated to ±0.3 by DJIInterface)
dji.requestSendStick(leftX=0, leftY=0.2, rightX=0.1, rightY=0)

dji.stopTelemetryStream()

The two-computer safety wrapper lives in lyrebird_groundstation.safety — see HTTP API.

GroundStation video dashboard

The video-test stack runs MediaMTX plus a browser dashboard for multi-drone video testing and stream diagnostics. It discovers phones, connects to telemetry on port 8081, displays stream health, and consumes video through WHEP.

Default services:

Service	Default URL / Port
Browser dashboard	http://localhost:8090
MediaMTX WebRTC / WHIP / WHEP	http://localhost:8889
MediaMTX API	http://localhost:9997
MediaMTX RTSP	rtsp://localhost:8554
ICE UDP	:8189

Useful restart command:

docker compose -f GroundStation/video_test/compose.yaml down
docker compose -f GroundStation/video_test/compose.yaml up -d
docker compose -f GroundStation/video_test/compose.yaml ps

Runtime diagnostics are written under GroundStation/video_test/logs/. Those logs are intentionally ignored by git.

Settings can be viewed and changed for each drone from the Settings tab: it reads and writes DJI flight limits (RTH altitude, max height/distance), RC pairing and stick mode, and app/video settings over HTTP, and shows read-only rows for the drone name, the detected aircraft model, and the control profile (speed/PID/gimbal profile) automatically selected for it — so you can confirm the right profile is active without opening the app on the phone.

Tab	What it shows
Video	Live WHIP/WHEP tiles per drone with quick FPS/loss/telemetry stats
Health	Correlated phone/sender/MediaMTX/browser diagnostics, worst symptom first
Video Charts	Decoded FPS, bitrate, packet loss, and jitter over time
Telemetry	Full nested live state tree per drone
Telemetry Charts	Battery, satellites, altitude, and Wi-Fi RSSI over time
Settings	View and change DJI/app settings per drone over HTTP
HTTP	The full /send/ catalogue, each entry marked if it also has a MAVLink form
MAVLink	What the aircraft reports and accepts as a MAVLink 2 vehicle, with an HTTP cross-check
ROS	Per-drone ROS topic liveness and rates from ros-monitor