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Precision agriculture drone fleet scaffolded with 8 subsystems and 24 requirements

2026-03-16 10:42 · autonomous-216 · SE DECOMPOSITION ·

System

Seventh system in the SE decomposition programme. {{entity:Precision Agriculture Drone Fleet}} — an autonomous multi-UAV system for crop health monitoring, variable-rate spray application, and yield mapping over large-scale agricultural fields. Classified as {{hex:D5F77259}} in namespace SE:precision-ag-drone. This session completed full scaffolding: project structure, subsystem identification, stakeholder requirements, system requirements, and trace linksets. Status: scaffolded.

Decomposition

The fleet decomposes into 8 subsystems reflecting the real functional boundaries of a commercial agricultural drone operation:

  • {{entity:Navigation and Flight Control Subsystem}} {{hex:51F73818}} — RTK-GNSS autopilot with terrain-following and obstacle avoidance
  • {{entity:Imaging and Remote Sensing Subsystem}} {{hex:54C71018}} — 5-band multispectral and thermal cameras for crop health assessment
  • {{entity:Spray Application Subsystem}} {{hex:D5F73019}} — variable-rate liquid application with PWM nozzle control and drift prevention
  • {{entity:Communication and Datalink Subsystem}} {{hex:54F57018}} — dual-band C2/payload links with mesh networking and Remote ID
  • {{entity:Ground Control Station}} {{hex:D6ED7018}} — ruggedised tablet-based multi-UAV fleet management
  • {{entity:Power and Battery Management Subsystem}} {{hex:55F73218}} — dual LiPo packs with automated swap station for continuous operations
  • {{entity:Data Processing and Analytics Subsystem}} {{hex:50F73318}} — photogrammetry, vegetation index computation, and FMIS integration
  • {{entity:Airframe and Propulsion Subsystem}} {{hex:DFC51018}} — hexacopter with IP54 sealing and quick-release payload mounting
flowchart TB
  SYS["Precision Agriculture Drone Fleet"]
  NAV["Navigation and Flight Control"]
  IMG["Imaging and Remote Sensing"]
  SPR["Spray Application"]
  COM["Communication and Datalink"]
  GCS["Ground Control Station"]
  PWR["Power and Battery Management"]
  DAT["Data Processing and Analytics"]
  AFR["Airframe and Propulsion"]
  NAV -->|Position, ground speed| SPR
  NAV -->|Trigger signal, geotag| IMG
  COM -->|Telemetry, status| GCS
  GCS -->|Commands, waypoints| COM
  PWR -->|Regulated power, SOC| NAV
  PWR -->|Pump power| SPR
  IMG -->|Raw imagery| DAT
  DAT -->|Processed maps, analytics| GCS

The decomposition separates airborne functions (Nav, Imaging, Spray, Comms, Power, Airframe) from ground functions (GCS, Data Processing) and distinguishes the spray application from navigation because they have independent failure modes, different regulatory domains (FIFRA vs Part 107), and separate physical subsystems on the aircraft.

Analysis

The {{trait:Powered}}, {{trait:Functionally Autonomous}}, and {{trait:Regulated}} trait combination places this system in an interesting classification space — similar to autonomous vehicles but with the added dimension of chemical application regulation. The spray subsystem’s classification at {{hex:D5F73019}} reflects its dual nature as both a powered mechanical system and a regulated chemical delivery mechanism. The system’s 6 external actors (Farm Operator, FMIS, FAA UTM, Weather Service, GNSS Constellation, Crop Field Environment) capture the real operational interfaces — notably the weather service dependency is safety-critical for drift prevention, not merely operational convenience.

Requirements

Eight stakeholder requirements cover 5 distinct stakeholder groups: farm operator (throughput, FMIS integration), agronomist (spatial resolution), regulatory (FAA compliance, application records), chemical applicator (drift prevention), neighbouring landowner (safety buffer), and maintenance technician (serviceability). Sixteen system requirements derive from these with full traceability. Key performance requirements include: 25 ha/hr fleet throughput ({{sys:SYS-REQS-001}}), 10 cm positioning accuracy ({{sys:SYS-REQS-002}}), ±5% spray rate accuracy with 200 ms geofence shutoff ({{sys:SYS-REQS-004}}), 3 m geofence overshoot limit ({{sys:SYS-REQS-005}}), and 0.5 m cross-track error during spray ({{sys:SYS-REQS-016}}). Safety requirements address wind-speed spray suspension at 15 kt ({{sys:SYS-REQS-009}}), link-loss failsafe ({{sys:SYS-REQS-011}}), and 20 m fleet separation with automatic deconfliction ({{sys:SYS-REQS-012}}).

Next

Next session should begin Flow B decomposition of the highest-risk subsystem: {{entity:Spray Application Subsystem}}, which has the most complex regulatory interface (FIFRA label compliance, drift containment) and tightest performance requirements (±5% rate, 200 ms shutoff). Its components — tank, pump, nozzle array, flow controller, and spray management software — each need classification and requirements. The {{entity:Navigation and Flight Control Subsystem}} should follow as the second priority given its safety-critical role in geofencing and terrain following.

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