WiFi Controlled 4WD Robot Car using NodeMCU | KitKraft DIY Robotics Project
Introduction Imagine controlling a powerful 4WD robot from any room in your house using just a web browser. In this project, we are building a WiFi-controlled 4WD Robot using NodeMCU (ESP8266). By connecting the robot to your home WiFi router, it hosts a local web page that acts as a remote control. Whether you're a student building an engineering project or a hobbyist exploring IoT, this "Station Mode" web server setup is a stable and professional way to dive into wireless robotics.
Why Build a WiFi Controlled 4WD Robot? Unlike Bluetooth robots that have a very limited range, this robot connects to your home WiFi network. This allows you to control the robot from a smartphone, tablet, or PC without installing any apps. As long as you are connected to the same router, you can simply type the robot's IP address into your browser and start driving!
Components Required
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NodeMCU (ESP8266): The WiFi-enabled microcontroller.
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L298N Motor Driver: To drive the 4 high-torque DC motors.
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4WD Robot Chassis Kit: Includes the base, 4 motors, and 4 wheels.
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2x 18650 Li-ion Batteries: Provides 7.4V of power for the motors and board.
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Jumper Wires & Power Switch: For connecting the logic and power circuits.
How It Works This robot operates as a Local Web Server on your home network:
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WiFi Connection: The NodeMCU connects to your home WiFi router using your SSID and Password.
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Hosting the Interface: Once connected, the NodeMCU hosts a simple HTML webpage.
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Web Control: When you enter the robot's IP address (e.g.,
192.168.1.15) into your phone's browser, the control page appears with buttons for Forward, Reverse, Left, Right, and Stop. -
Action: Clicking a button sends an HTTP request to the NodeMCU, which then signals the L298N Motor Driver to move the wheels.
Step-by-Step Instructions
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Chassis Assembly: Secure the four DC motors to the 4WD chassis and attach the wheels. For a detailed visual guide on how to put the mechanical parts together, check out this video: 🔗 Watch: 4WD Robot Chassis Assembly Guide
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NodeMCU to L298N Wiring: Using your specific code configuration, connect the pins as follows:
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D2 (GPIO 4): ENA (Speed Right)
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D3 (GPIO 0): IN1 (Direction Right)
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D4 (GPIO 2): IN2 (Direction Right)
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D6 (GPIO 12): IN3 (Direction Left)
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D7 (GPIO 13): IN4 (Direction Left)
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D8 (GPIO 15): ENB (Speed Left)
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Power Management: Connect your 18650 battery pack to the L298N's 12V input. Important: Ensure the GND (Ground) of the NodeMCU and the L298N are connected together to complete the circuit.
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Coding the Web Server: Open the Arduino IDE, enter your WiFi credentials (SSID and Password) into the sketch, and upload it to the NodeMCU.
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Find Your Robot’s IP: Open the Serial Monitor (115200 baud) after uploading. Once the robot connects to your WiFi, it will display an IP Address. Enter this IP into your smartphone browser to see the control panel.
💡 Pro-Tip: Speed Control By using the ENA and ENB pins (D2 and D8), you can use analogWrite() in your code to control the speed of the motors. This prevents the robot from "jumping" and allows for much smoother turns!
Code > Arduino You can find the full source code for the Web Server interface on our GitHub repository: 🔗 Download Code: Click Here
Video Tutorial Check out the assembly and a live driving test through a smartphone browser: 🔗 How to Build a NodeMCU WiFi Robot (Local Web Server)
Shop the Components Everything you need for this project—from the 4WD chassis to the NodeMCU board—is available at Kitkraft.in. We offer high-quality kits designed to help students and makers bring their ideas to life.
Conclusion The WiFi-controlled 4WD robot is a perfect introduction to the world of the Internet of Things (IoT). By using a local web server, you've created a platform that can be easily expanded—you could add an ultrasonic sensor for obstacle avoidance or even an ESP32-CAM for FPV driving!
Did you enjoy this project? Share your build with us by tagging #KitkraftIndia on social media!