Redson Dev · Idea
Smart Parcel Drop-off Notifier with ESP32
Published June 10, 2026
This project is for small businesses or individuals who receive many parcels and need an automated way to know when deliveries arrive without constant checking. Users can build a simple device that detects when a parcel is placed in a designated drop-off box or area and sends an instant notification to their phone or computer. For instance, a small independent crafts studio could use this to get alerts when material deliveries arrive, ensuring timely processing.
What you'll need
- ESP32 development board (e.g., ESP32 NodeMCU dev kit) x1
- HC-SR04 ultrasonic sensor x1
- Breadboard x1
- Jumper wires (male-to-male) x10
- Micro USB cable x1
- 5V USB power adapter x1
- Small project enclosure (optional) x1
Step-by-step
- 01
Set up the ESP32 Development Environment
Install the Arduino IDE if you haven't already. Go to File > Preferences and add the ESP32 board manager URL. Then, open Boards Manager (Tools > Board > Boards Manager), search for 'ESP32', and install the 'ESP32 by Espressif Systems' package. Select your ESP32 board from Tools > Board.
- 02
Wire the Ultrasonic Sensor to ESP32
Connect the HC-SR04 VCC pin to the ESP32's 5V pin, GND to GND. Connect the Trig pin of the sensor to ESP32 GPIO pin 16, and the Echo pin to GPIO pin 17. Use the breadboard for stable connections and to easily connect multiple wires if needed.
- 03
Program the ESP32 for Distance Sensing
Write a sketch in Arduino IDE to read distance data from the HC-SR04 sensor. Use the 'NewPing' library (if available, install via Sketch > Include Library > Manage Libraries) for easier sensor interaction. The code should continuously measure distance and, if it falls below a certain threshold (indicating a parcel), trigger an event.
- 04
Implement Notification Logic
Integrate a notification service. A simple way is to use a webhook service (like IFTTT Webhooks or a custom self-hosted webhook receiver) to send an HTTP POST request from the ESP32 when a package is detected. Configure the webhook to then send an email, a push notification, or update a status on a dashboard.
- 05
Test and Calibrate the System
Upload the code to your ESP32. Power the device and place it within your parcel drop-off area. Place an object (simulating a parcel) in the detection zone and verify that the notification is received. Adjust the distance threshold in your code for optimal detection based on your setup.
Tips
- Enclose the sensor in a small, weather-resistant box if used outdoors to protect it from elements.
- Consider adding a small status LED to the ESP32 to visually confirm when it detects something or is connected to Wi-Fi.
- For power efficiency, implement deep sleep on the ESP32 and wake it up periodically or via an external interrupt if continuous monitoring isn't strictly necessary.