In the previous project, we discussed how to wake ESP32 using EXT0. ESP32 supports five power modes: active, modem sleep, light sleep, deep sleep, and hibernation. For battery-powered or Internet-of-Things (IoT) applications, deep sleep mode is particularly useful. In this mode, the ESP32 powers down most components, including the CPU, flash memory, Wi-Fi, Bluetooth, and…
How to design a distance meter using ESP32
The Internet of Things (IoT) has transformed how we interact with one another and our environment. As devices become smarter and more connected, do-it-yourself (DIY) projects have become increasingly popular. One such project involves developing a distance meter using the ESP32, a versatile microcontroller with built-in Wi-FI, Bluetooth connectivity, and diverse capabilities. This project highlights…
How to create an RFID-based locker system using Arduino
Need somewhere to secure a few items? No problem! In this project, we’ll design an RFID-based locker system that offers a reliable and convenient solution for securing objects using radio frequency identification (RFID) technology. Working operation: The RFID locker system The RFID reader scans a unique tag, and if it matches a pre-registered one, the…
How to design an Arduino-based traffic light system
Traffic light systems are important signaling devices that regulate the flow of vehicles and pedestrians at intersections, crosswalks, and other critical areas. These systems use three primary lights — red, yellow (amber), and green — to manage traffic effectively and ensure safety. In this project, we’ll create a traffic light system for a four-way intersection…
How to capture images using ESP32-CAM and an SD card
The ESP32-CAM is a widely used development board for embedded vision applications. It combines the ESP32 microcontroller with an OV2620 camera module, and the ESP32 itself comes with built-in Wi-Fi and Bluetooth capabilities. Previously, we created a video streaming server using the ESP32-CAM to troubleshoot potential operational issues with the module. In this project, we’ll…
How to design an Arduino-based meditation device
Meditation is a practice that involves focusing the mind and cultivating awareness, often to achieve a state of mindfulness, mental clarity, inner peace, or spiritual connection. It’s used across cultures and traditions to reduce stress, improve emotional well-being, and enhance self-awareness — making it a valuable tool for mental and physical health. There are several…
Arduino-based token display board controller
You must have noticed token display boards at many places like food stores, hospitals, banks, various takeaways, etc. Token display systems are used to display token numbers. As these display boards show numeric information, these are easily designed using 7-segment LEDs. The commercial models use large 7-segment LEDs to display token numbers. It is even…
How to build a smart system using Arduino that alerts drivers of fatigue
Road safety is a critical concern, with driver fatigue and distractions among the leading causes of accidents. In this project, we’ll devise a smart system using Arduino UNO and a blink-eye sensor to monitor driver alertness. If the driver shows signs of drowsiness, the system takes proactive measures to prevent a potential accident. This includes…
How to make a smart dustbin using Arduino?
Smart technology refers to devices and systems that use advanced computing, connectivity, and data analytics to enhance functionality and efficiency. Devices such as smartphones, watches, and appliances connect to the Internet and one another via the Internet of Things (IoT), allowing for real-time data exchange and remote control. One innovative application of this technology is…
How ESP32 boards can communicate without a router or the Internet
ESP-NOW is a connectionless communication protocol developed by Espressif for wireless data communication between ESP boards. It allows ESP boards like ESP8266, ESP32, ESP32-C, and ESP32-S to communicate directly without a router or Internet connectivity. This enables a private wireless network among ESP devices, eliminating the need for a router, gateway, or Internet access for…
How to use a wireless joystick to remotely control two servo motors
A dc servo motor provides precise motion control, enabling accurate positioning and speed regulation in various applications. It consists of a rotary or linear actuator, which allows for such precise control of angular or linear position, velocity, and acceleration. It’s used in several sectors, including: Robotics Industrial automation Angular load positioning Avionics Automobiles A few…
How to set-up and build a project using Arduino IoT Cloud
Arduino IoT Cloud, also known as simply Arduino Cloud is a popular Internet-of-Things (IoT) platform for creating, deploying, and managing IoT projects. The platform was launched in 2019 as a Beta version similar to other platforms, such as Blynk. Since then, Arduino Cloud has undergone several upgrades, adding unique features. It’s best known for its…
How to set-up and use the Heltec LoRa 32 board
Heltec Lora-32 is a high-quality Wi-Fi LoRa (long-range) development board that competes with the Lilygo TTGO T-LoRa32, RAKwireless WisNode LoRaWAN RAK811, and STMicroelectronics Nucleo boards. What differentiates Heltec LoRa-32 is that it’s more than a LoRa-only device, offering Bluetooth and Wi-Fi capabilities. This allows Heltec to easily integrate into existing network infrastructure in an Internet-of-Things…
How to build an alcohol detector with the MQ3 gas sensor
Depending on the country, as many as 25 to 35% of motor vehicle accidents happen because of drunk driving every year. When drivers consume alcohol, they not only put themselves at risk but others on the road. Fortunately, such accidents are preventable with a combination of education, personal responsibility, and community efforts. There are also…
How to design pick-and-place robot using Arduino
In this project, we’ll design an omnidirectional, moving pick-and-place robot. First, let’s cover how the robot is built. The robot’s build As shown in Figure 1, the robot consists of two sections: An omnidirectional moving platform A robotic arm The omnidirectional platform The robot is built using one circular wooden plate, three dc gear motors,…
How to use the TCS230/TCS3200 color-recognition sensor with Arduino
Color detection is the process of identifying and distinguishing colors within an image, video, scene, or object. Many embedded and robotic applications require this feature, as it’s useful for sorting, selection, test strip reading, path determination, and more. Two standard sensors used for color detection include TCS230 or TCS3200. TCS3200 recognizes various colors based on…
How to play MP3 files on Arduino using the DFPlayer Mini or the MP3-TF-16P
Including an audio option with an electronic or Internet-of-Things (IoT) project is often an ideal addition. However, microcontrollers cannot process MP3 files, which is the most common audio file format. Fortunately, there is a solution. It is possible to play MP3 audio files on Arduino using dedicated MP3 decoders like the DFPlayer Mini or MP3-TF-16P.…
How to design an OTP-based door lock
Today, mobile-based authentication to verify a person’s identity is common. Online service providers often use it for access to services, approval of transactions, or to change a user’s credentials. Imagine using a similar mobile-based authentication to enter your home, office, or any private space. It’s possible. In this project, we’ll design a mobile-based access system…
How to make an IoT-based analog clock using ESP32
In this project, we’ll design an analog display clock using ESP32. The clock is an Internet-of-Things (IoT) device that retrieves the local time from a Network Time Protocol (NPT) server and displays the time (as well as the date) like an analog clock. The display used to build this IoT clock is SSD1306. However,…
How to design an app-controlled irrigation system
In this project, we’ll design a mobile app-controlled watering system that drip irrigates a home garden or small farm. This system is developed on an ESP8266 microcontroller, which controls the water pump through a 3V relay or an electronic valve. The user can switch the water’s motor/electronic valve ON or OFF and even set a…