ESP32 Mesh Network for Halloween Prop Control

This project uses a mesh network of ESP32 microcontrollers communicating via ESP-NOW to coordinate a set of Halloween props. The goal is to create synchronized, responsive effects triggered by motion — perfect for haunted house setups or outdoor displays. 

 System Overview 

 The network consists of one master controller and multiple slave controllers : 

 

 

 Master Node: Acts as the central coordinator. It’s equipped with a motion sensor (such as a PIR sensor) that detects when someone approaches. When motion is detected, the master broadcasts a “trigger” message over ESP-NOW to all slave nodes. 

 

 

 Slave Nodes: Each slave node controls an individual prop (e.g., fog machine, servo motor, LED lighting, sound module, etc.). Upon receiving the master’s trigger message , the slave performs its assigned action — for example, moving a prop, flashing lights, or playing a sound. Once the action is complete, the slave sends a “completed” message back to the master. 

 

 

 Communication Flow 

 

 

 Motion Detection: The master’s PIR sensor detects movement. 

 

 

 Broadcast Trigger: The master sends a “motion detected” message via ESP-NOW to all registered slave devices. 

 

 

 Action Execution: Each slave performs its programmed effect or animation. 

 

 

 Completion Feedback: After finishing, each slave sends a “done” signal to the master. 

 

 

 Reset or Cooldown: Once the master receives all “done” signals (or after a timeout), it resets the system and waits for the next motion event. 

 

 

 Key Features 

 

 

 ESP-NOW protocol allows for low-latency , Wi-Fi-free communication — no router or internet required. 

 

 

 Scalable design — easily add or remove props by pairing additional ESP32s. 

 

 

 Bidirectional communication ensures the master knows when all props have completed their sequences. 

 

 

 Energy-efficient — nodes can sleep between triggers. 

 

 

 Highly customizable — each slave can have its own timing, behavior, or randomized effect. 

 

 

 Example Use Case 

 

 

 Master detects motion → broadcasts “TRIGGER” 

 

 

 Slave 1 (fog machine): starts fog → sends “DONE” after 10 seconds 

 

 

 Slave 2 (LED lights): flashes red and orange → sends “DONE” after 5 seconds 

 

 

 Slave 3 (servo skeleton): waves arm → sends “DONE” after 8 seconds 

 

 

 Once all “DONE” signals are received, the master resets and waits for the next visitor. 

 

 

 List of mac addresses currently in use:  

 master (detects motion): FC:B4:67:55:A5:24 

 sound player: 08:D1:F9:EE:A0:B0