MECH-CTRL

Mechanical Irrigation β€” Multi-Node Majority-Vote Control System

Soil Moisture Sensor Nodes β€” Click to Toggle State
Vote Result
0 / 4 dry votes
Awaiting readings...
threshold
β‰₯2
votes to trigger
Actuator Status
πŸ”§
Solenoid Valve (N.C.)
12V / latching relay
CLOSED
πŸ’§ Β· Β·
Sprinkler Head
pressure-driven scatter
STANDBY
Control Flow
β‘  Soil Resistance Sensing
Porous ceramic probes measure soil conductivity
β‘‘ Analog Comparator Decision
LM393 threshold compare β†’ dry/wet digital signal
β‘’ Mechanical Vote Adder
Relay series/parallel β†’ majority-vote logic
β‘£ Valve Trigger
Latching relay opens valve β†’ water pressure drives sprinkler
β‘€ Auto Shutoff on Recovery
Majority nodes wet β†’ vote flips β†’ valve closes

Vote Threshold

Dry nodes required to trigger 2 / 4
Current: spray activates when β‰₯2 nodes dry

Truth Table (4 nodes)

S1S2S3S4DrySpray

Sensor Circuit Schematic

// Single-node moisture detection VCC(3.3V) β”‚ [10kΞ©] ← pull-up resistor β”‚ β”œβ”€β”€β†’ LM393(+) comparator +in β”‚ [soil probes] ← porous ceramic electrodes β”‚ dry β‰ˆ 300kΞ© GND wet β‰ˆ 5kΞ© // Threshold setting (βˆ’in) VCC─[R1]─[R2]─GND β”œβ†’ LM393(-) // Adjust R1/R2 ratio to // set the moisture trigger point output: HIGH=dry / LOW=wet

Vote Logic Implementation

// Relay majority vote (threshold=2) // Option A: relay series counter S1─[RLY1]─┐ S2─[RLY2]─┼─→ current adder S3─[RLY3]── ↓ S4─[RLY4]β”€β”˜ [threshold relay] ↓ valve trigger signal // Option B: pure mechanical lever sum 4 float weights stack up β†’ exceed spring preload force β†’ trigger valve open

Simulation Controls