Example 27: Vibration Sensor

Experiment Overview

A vibration sensor (SW-420) outputs a digital signal when vibration is detected, suitable for anti-theft alarms, collision detection, and similar applications. The sensor internally uses a spring-type contact that disconnects and outputs HIGH when vibration occurs.

Hardware Wiring

Board Label	GPIO Pin	Connected Device
VIB	GPIO4	Vibration sensor digital output (DO)

JSON Configuration Example

{
  "peripherals": [
    {
      "id": "vibration_01",
      "name": "Vibration Sensor",
      "type": 18,
      "enabled": false,
      "pins": [4],
      "params": {}
    }
  ]
}

Peripheral Execution Linkage

Scenario: Vibration Alarm (Event Trigger)

Feature: Trigger buzzer alarm for 2 seconds when vibration is detected

Web UI Configuration Steps

Step 1: Ensure Buzzer Peripheral is Configured

• Peripheral ID: buzzer_gpio
• Type: GPIO Output

Step 2: Create Rule

1. Click Peripheral Execution in the left menu
2. Click New Rule button
3. Fill in basic configuration:
   • Rule Name: Vibration Alarm
   • Report Data: ✅ Enabled
   • Enable: ✅ Enabled

Step 3: Configure Trigger (Event Trigger)

1. Click Add Trigger button

2. Fill in trigger configuration:

   Field	Value	Description
   Trigger Type	Select Event Trigger	Respond to interrupt events
   Event Type	100	GPIO interrupt event
   Event Source	vibration_01	Vibration sensor peripheral ID

Step 4: Configure Actions (3 actions required)

Action 1: Buzzer ON

1. Click Add Action button
2. Fill in:
   • Action Type: Select HIGH
   • Target Peripheral: Select buzzer_gpio

Action 2: Delay 2 Seconds

1. Click Add Action button again
2. Fill in:
   • Action Type: Select Delay
   • Action Parameter: 2000

Action 3: Buzzer OFF

1. Click Add Action button a third time

2. Fill in:

   • Action Type: Select LOW
   • Target Peripheral: Select buzzer_gpio

3. Click Save button

Detection Method Comparison

Method	Peripheral Type	Advantage	Disadvantage
Interrupt Trigger	type: 18	Fast response, power-efficient	May trigger multiple times
Polling Detection	type: 11	Simple and reliable	Uses CPU

Notes

1. Sensitivity Adjustment: Some modules include a potentiometer for sensitivity adjustment
2. False Triggers: At high sensitivity, wind and sound can trigger the sensor
3. Interrupt Method Recommended: Use rising edge interrupt (type: 18) to avoid polling overhead
4. Debouncing: A single vibration may produce multiple triggers; set a 1-2 second cooldown period