Docks

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A dock is what turns a scouting service into an autonomous network. It is also the point where the regulatory work becomes larger than the engineering work.

Read Regulation before costing anything on this page.

What a dock has to do

FunctionThe hard part
Open and closeA moving lid outdoors for years, in wind, ice and dust
Precision landGNSS alone lands within a metre. A dock needs centimetres
ChargeContact pads need alignment; wireless needs money
ConditionDry and warm the aircraft, or the next dawn flight starts iced
Report weatherThe go decision comes from the dock, not the forecast
Fail safeA dock that cannot close must not launch
ConnectLTE, with enough local autonomy to survive a dropped link

Buy or build

TurnkeyDIY
ExampleDJI Dock 3Enclosure, actuator, charger, marker, compute
SupplierSolectric and DJI Enterprise dealers (EU), Advexure (US)See the parts list below
Cost€15,000 to €40,000 with aircraft€2,000 to €6,000 plus your own aircraft
Time to first flightWeeksMonths
Environmental testingDoneYours
Payload choiceTheir aircraft, their payloadsAnything you can build
Authorisation caseManufacturer documentation supports itYou write the safety case from scratch

Buy the first one. The capability's value is the schedule it keeps, and proving that on somebody else's hardware is far cheaper than discovering your lid mechanism seizes at -5 °C in February. Build docks afterwards, for payloads the turnkey systems do not carry, above all radiometric thermal and calibrated multispectral.

Other turnkey vendors worth quoting: Heisha (airframe-agnostic charging pads and enclosures), and the dock lines from the major enterprise UAS manufacturers.

DIY parts list

ItemChoiceEU sourceUS sourceIndicative
Enclosure, IP66, 800 mm classSteel or GRP cabinetRittal, Fibox via ReicheltDigiKey€300 to €900
Lid actuatorsLinear, IP65, with limit switchesIgusServoCity€150 to €400
Landing padCentring funnel or V-rails, plus contactsfabricatefabricate€100 to €300
Charging contactsSpring-loaded pins, gold platedMouser EUDigiKey€50 to €150
Wireless chargingIf contact alignment defeats youWiBoticWiBotic€2,000 to €4,000
Battery chargerThe aircraft's own, mounted and controlledmanufacturermanufacturer€200 to €500
Precision landing markerPrinted AprilTag plus an IR beaconprint, IR-LOCKIR-LOCK€30 to €200
Dock computerPi 5, or an industrial fanless PCBerryBaseThe Pi Hut€90 to €500
Weather stationWind, rain, temperature, humidityDavis Vantage Pro2, or an anemometer plus SHT45Davis€80 to €1,200
Router, dual SIM failoverTeltonika RUTX11Teltonika resellersSparkFun€200 to €300
Heater and dehumidifierCabinet heater with a hygrostatReicheltDigiKey€60 to €200
Solar and battery, off grid600 W panel, 200 Ah LiFePO4, MPPTVictron via AntratekRobotShop€900 to €2,500
UPS, on gridRide through a brownout mid-cycleReicheltDigiKey€150 to €400
Camera, internal and externalSee the aircraft, see the siteany IP cameraany€80 to €300

Precision landing

The one part that must work every time. Layer it:

  1. RTK approach to about 1 m.
  2. Visual marker from 15 m down: an AprilTag or ArUco pattern read by a downward camera, driving ArduPilot's or PX4's precision landing mode.
  3. IR beacon as the low-light and wet-lens fallback.
  4. Mechanical centring for the last few centimetres: a funnel or V-rails that pull the aircraft into alignment as it settles.

Mechanical centring is what makes contact charging viable. Do not try to land on pads with software alone.

Siting

The single highest-value hour of a deployment.

ConsiderationRule of thumb
CoverageEvery target block within half a battery, one way
PowerGrid beats solar by a wide margin. A yard, pump house or mast base is worth a detour
DataCheck the LTE signal at the exact spot, not at the gate
AirspaceCheck the approach paths, not just the dock position
AccessYou will visit it. Snow, mud, a locked gate
Sky viewClear GNSS horizon, away from buildings and trees
ConsentLandowner agreement in writing, including for the flight paths

One dock covering four blocks beats four docks. Spend the hour on a map with battery ranges drawn on it before you buy anything.

In-house software

ComponentWhat it does
Dock state machineclosed, opening, ready, launched, flying, returning, landing, charging, fault. Every transition logged
Go/no-go gateWind at altitude, precipitation, visibility, light, aircraft battery health, dock health
Mission dispatchWhich route, which payload, which battery, in which window
Fleet schedulerExtends ScheduleCapabilityFlights with weather, daylight and battery constraints
Health telemetryDock cycles, lid current draw, charge cycles, internal humidity
Remote recoveryA supervisor can abort, recall or ground an aircraft at any time

The lid actuator current draw is worth logging from day one: a lid that starts drawing more current is the earliest warning of a mechanism about to fail, and a failed lid on a wet night is an aircraft you replace.

The failure modes to design against

FailureResponse
Lid will not openNo launch. Alert. The aircraft stays safe
Lid will not close after landingAlert loudly. Heater on. A human goes out
Aircraft cannot dockDivert to the next dock in range, else land at a pre-surveyed safe area
Link lost in flightContinue the route and return. Never hold
Battery below reserveReturn now, drop the rest of the route, report the missed flight with its reason
Weather turns mid-flightReturn. Log the wind figure
Dock loses powerDo not launch. Report on the backup link

Every one of those decisions goes into the missed flight report. "Weather cancelled, gust 12.4 m/s at 06:12" is a report a customer trusts. "Flight did not happen" is not.