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Presence Simulation Engine: Randomized Occupancy Patterns to Deter Burglars When Away

Presence Simulation Engine: ระบบจำลองผู้อยู่อาศัยเพื่อป้องปรามขโมยเมื่อบ้านว่าง

May 12, 2026 · 1 min read
Presence Simulation Engine: Randomized Occupancy Patterns to Deter Burglars When Away

Presence Simulation Engine: AI Behavioral Mimicry for Vacancy Security

Professional burglars surveil properties for days before striking, looking for consistent lighting patterns, absence of sounds, and absence of movement. A Presence Simulation Engine uses real behavioral data from your family to generate randomized occupancy patterns that cannot be distinguished from genuine presence.

Core Concept: Markov Chain Occupancy Model

Instead of rigid timers (lights on 18:00–22:00 — patterns that repeat and can be learned), the engine uses a Markov Chain to generate probabilistic but realistic state sequences: - States: {TV_on, living_room_light, bedroom_light, bathroom_light, kitchen_light, audio_on} - Transition matrix derived from 30 days of actual household behavior logs - Inter-transition time drawn from Gaussian distribution (mean 15–45 min, σ 5 min)

Home Assistant AppDaemon Implementation

A Python AppDaemon class loads the learned transition matrix, samples the next state every 5 minutes when away mode is active, and applies changes gradually (dimmer fade rather than instant on/off) to simulate natural human behavior.

Simulated Signals

Lighting: Zigbee dimmers (IKEA TRADFRI or Shelly Dimmer 2) with gradual brightness changes — bedroom fading down before simulated bedtime, kitchen flickering on briefly for simulated meal prep, bathroom cycling every 1–3 hours.

Audio: Google Home or Sonos playing low-volume Thai TV broadcast audio or TTS dialog clips at randomized intervals and volumes.

Exterior: Lights activated at true local sunset time (Home Assistant Sun integration); garage smart socket simulates plugged-in vehicle.

Appliances: TV smart plug showing occasional active power draw; washing machine operating 2–3 times per week on the household’s historical schedule.

Anti-Pattern Enforcement

The engine monitors its own output to prevent repetition: no identical 7-day sequence allowed, minimum entropy enforced on state sequences, simulation start time randomized ±30 minutes daily.

Pilot Results

In a 60-day Bangkok pilot, five uninformed neighbors consistently assumed the home was occupied. Frigate zone analytics showed a significant decrease in lingering activity near the perimeter compared to the baseline period. Electricity cost increase: 150–300 THB/month.

Questions & answers

How does Presence Simulation differ from traditional timers?
Traditional timers create the same pattern every day — a pattern burglars can learn in a few days of surveillance. Presence Simulation uses Markov Chain modeling to generate different sequences daily that remain statistically realistic but never repeat.
What hardware is required?
Home Assistant server (Raspberry Pi 5 or Intel NUC), Zigbee dimmers for key rooms, smart plugs for appliances, and a smart speaker for audio simulation. Total hardware cost: 5,000–12,000 THB.
How much extra electricity does it consume?
Approximately 150–300 THB/month extra, since devices run in short bursts rather than continuously — a trivially small insurance cost against burglary losses.

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