Project idea
Build a compact, low‑cost 2‑wheel differential drive robot that follows a dark or light line using IR reflectance sensing and an 8051 microcontroller decision loop. Sensor states are decoded to steer left/right/forward/stop by toggling L293D H‑bridge inputs, enabling robust tracking on contrasting surfaces.
 
Project description
Two IR sensor modules detect line reflectivity and feed digital signals to the 8051, which computes motion decisions and drives two DC motors through the L293D to keep the robot centered on the path. The build uses a 2WD chassis with BO motors, modular IR sensors, and basic passives on breadboard/PCB, and can be upgraded with ultrasonic sensing for obstacle avoidance without altering the core control loop.
 
Components list
8051 Microcontroller
DC Motor (x2)
Robotic Chassis
Motor Driver IC (L293D)
IR Transmitter Receiver (IR sensor modules, x2)
Resistors
Capacitors
Transistors
Cables and Connectors (jumper wires)
Diodes (1N4007)
PCB and Breadboards
LED
Push Buttons
Switch
IC
IC Sockets (40‑pin)
 
Features
2‑sensor line detection and closed‑loop control with 8051 for reliable tracking on contrasting lines.
Dual H‑bridge motor drive using L293D for bi‑directional DC motor control and simple PWM‑based speed handling.
Modular expandability to add obstacle sensing (e.g., ultrasonic) without changing the basic line‑following algorithm.
 
Applications
Factory and warehouse line‑guided material movement and education demos for autonomous navigation principles.
Robotics workshops, competitions, and academic labs teaching sensors, control logic, and motor driving with 8051.
 
Project Includes:
Fully assembled and tested circuit
Circuit diagram
Source code 
(For DIY KITs - only the components will be provided)
 
Project Types:
DIY KIT(Do IT YourSelf KIT) - We are providing only components in this kit for this project
DIY KIT with Code & Circuit Connections - Along with the components, you will get the Code and the Circuit Connections file to help you build the project easily.
Readymade Breadboard - We are providing fully assembled, tested and ready-made project using plug-n-play jumper wires and breadboard with all the other components, code & circuit diagram.
Readymade Soldered - We are providing fully assembled, tested and ready-made project soldered on a PCB with all the other components, code & circuit diagram.
 
Dimensions (cm)
Approx 25 × 13 × 6 cm based on common 2WD chassis formats used for small line followers.
 
Shipping dimensions (cm)
Approx 30 × 20 × 10 cm boxed to accommodate chassis, motors, electronics, and padding for courier handling in India.
 
Weight
Approx 0.50 kg assembled, dominated by the metal chassis and motors in typical 2WD builds.
 
Estimated project weight
0.50–0.60 kg including wiring, breadboard/PCB, and IR modules in a robust academic kit build.
 
Notes: All the products are made by LearnElectronics India and not for re-sale.