Embedded·Jan 1, 2022

Automatic Street Light

Light-dependent street-light controller that turns lighting on at dusk and off at dawn.

Overview

This project automates street or outdoor lighting using ambient-light sensing. The circuit measures surrounding light through an LDR and switches the lamp or LED output when the level crosses a threshold. It is a simple, practical energy-saving control system for outdoor lighting.

Specifications

RoleCircuit designer and prototype builder

SensorsLDR light sensor

ModulesRelay / transistor switchLED or lamp load

ProtocolsAnalog thresholdGPIO

Tech tagsLDRAutomatic LightingRelayEnergy SavingEmbedded

Architecture

Ambient light sensor feeds a threshold circuit/controller. The output switch turns lighting on in darkness and off in daylight.

Project photos

Videos

Implementation details

Firmware

Firmware or analog threshold logic reads the LDR level and switches the output with hysteresis to avoid flicker around the transition point.

Power

Low-voltage control section switches the lamp/load through a driver or relay stage.

Components / BOM

LDR, Comparator or microcontroller, Relay/transistor switch, LED/lamp load

Engineering challenges

Preventing flicker during dawn/dusk transition is the main practical concern.

Solutions

Used threshold control and simple delay/hysteresis behavior to stabilize switching.

Results & metrics

Demonstrates automatic lighting control from ambient brightness.

Future improvements

Add solar charging, motion-based dimming, waterproof enclosure, and remote monitoring.