Project idea: Two IR sensor pairs placed a known distance apart start/stop a microcontroller timer, compute speed using speed formula show it on a 16×2 LCD, trigger a buzzer on overspeed, and wirelessly notify a remote receiver for enforcement.
 
Project description: An AT89S52-based controller reads two IR gates, calculates speed from measured transit time, compares it to a preset limit, displays live speed on a 16×2 LCD, and activates a buzzer and lamp on violations while pushing an event packet over a 433 MHz RF link to a remote station for logging and action. Development uses Keil C51 toolchain in C, aligning with standard 8051 workflows for build and HEX generation.
Components
 
Total list of components (names only):
AT89S52 8051 microcontroller
IR transmitter–receiver sensor pairs (2 units)
16×2 LCD display
433 MHz RF transmitter–receiver pair
5 V piezo buzzer
12 V indicator lamp
12 V 1 A DC adapter
7805 voltage regulator IC
11.0592 MHz crystal with load capacitors
Resistors
Capacitors
General-purpose transistors
Diodes
LEDs
Push buttons
Power/slide switch
IC sockets
Cables and connectors
General-purpose PCB and breadboard
ABS project enclosure
 
Software specifications: Keil uVision C51 compiler; language: C.
Features
 
Key features:
Automatic speed measurement using dual IR gates and microcontroller timing, independent of ambient light with proper IR modules.
Live speed display on 16×2 LCD and local audiovisual alert on overspeed.
Wireless event transmission via 433 MHz RF link up to typical short-range distances for remote logging.
 
Where it fits:
Highways and expressways for overspeed surveillance at fixed stretches.
Campuses, residential societies, and industrial roads for speed calming and logging.
Physical
 
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. 15.1 × 9.0 × 5.3 cm using a compact ABS enclosure of similar class.
 
Shipping dimensions (cm): Approx. 20 × 15 × 10 cm including enclosure, cabling, padding, and accessories.
 
Weight (net): Approx. 0.45 kg, dominated by enclosure mass with electronics inside.
 
Estimate project weight (gross): Approx. 0.65 kg with packaging and padding for shipping safety.
 
Notes: All the products are made by LearnElectronics India and not for re-sale.