Electronics projects are always in high demand. Students work on them to improve their skills, whereas hobbyists like the fun in meddling with technology. For professionals, it’s a different ball game altogether. Mini projects form a middle ground for all segments of electronics engineers looking to build. We compiled a list of interesting and practical mini project ideas for you to work on. Let’s look.
GPS on ATmega
Smart phones and GPS are nothing new for a techie. It not only gives information about location but also information like time, date, height and speed. It is so useful that most smartphones are embedded with it. However, for some of you out there, this mini project idea might be something to get your hands on. Based on ATmega 16A, this uses a GPS receiver.
This mini project is available at: ATmega16A Based GPS Receiver
PC based GPS
If working with ATmega gets too much for you, we have an alternative as well. This next project designs a system that connects a GPS module to a PC com port, which enables you to use GPS on a PC. A catch, you are going to have to be careful while handling the devices, as the pins of the com port might be too sensitive for rough usage.
This mini project is available at: PC-Based GPS Receiver
Low Power Inverter
Here is a simple low power inverter that converts 12V DC into 230-250V AC. It can be used to power very light loads like window chargers and night lamps, or simply give shock to keep the intruders away. The circuit is built around just two ICs, namely, IC CD4047 and IC ULN2004.
This project is available at: Low power inverter
LPG leakage detector
The circuit for an LPG leakage detector is readily available in the market, but it is extremely expensive and usually based on a microcontroller (MCU). This next mini project is for a low-cost circuit for an LPG detector that you can build easily. The next time there is a leakage, you can easily be on top of things.
This mini project is available at: Low-Cost LPG Leakage Detector
Geyser timer circuit
This geyser timer circuit sounds an alarm after the set timing of 22 minutes when the water is heated up. The circuit comprises a timer IC 555 wired as an astable multivibrator with adjustable time period of 15 seconds.
This project is available at: Geyser timer
Automatic Off Timer For CD Players
This automatic off timer starts functioning when you switch off your bedroom light and will turn your CD player ‘off’ after a predetermined time. In the presence of ambient light, or when you switch on light of the room in the morning, the CD player will again start playing. Unlike the usual timers, you don’t have to set this timer before sleeping.
This project is available at: Automatic off timer for CD players
Doorbell cum visitor indicator
This doorbell cum visitor indicator circuit can give identification of the visitor to your home in your absence. When you’re home, you can use it simply as a normal doorbell. The circuit comprises a monostable built around timer IC 555, relay driver transistor BC548, inverter section built around IC 7404, latching section built around IC 555 and LED display driver transistor BC548.
The project is available at: Doorbell cum visitor counter
An absolute necessity of every electronics lab is a workbench power supply. The power supply should be regulated and protected against short circuit. Most power-supply protection circuits use a low-value, high-wattage resistor connected in series with the load for current sensing. The voltage drop across the sensor resistor is weighed to activate the protection circuit. The given electronic fuse circuit is based on a poly-fuse application, which is a re-settable fuse by itself.
This project is available at: Electronic Fuse
Sonar water level meter
We all know a major part of the earth’s surface is filled with water. The water statistics for you house is on similar terms. You fill up your water tank everyday again to refill it every day. This project helps you in designing a water level meter to check up on the amount of water in the tank. Earlier systems used metal which got rusted over time. Whereas this next system is contactless resulting in no such problems.
This mini project is available at: Sonar Water-Level Meter
This next mini project is an ultra-sensitive fire sensor that activates an alarm when it detects fire. Thermistor based fire alarms work well when the thermistor is in close vicinity. In this circuit, a sensitive PIN diode is used as a fire sensor for a longer-range fire detection. This project can be set up as a safety precaution in your own house after its completion.
This mini project is available at: PIN Diode Based Fire Sensor
Thermostat for fridge
A thermostat is a standard equipment for sensing temperature of a system and maintaining it at a pre-defined point. It is a regular feature in air-conditioners, room heaters and refrigerators. Although some commercially-available refrigerators have inbuilt thermostats, the given mini projects idea is easy to build and automatically turns on or turns off the appliance at pre-set temperatures.
This mini project is available at: Electronic Thermostat for Fridge
LED Based Emergency Lamp
White LEDs are replacing the conventional incandescent and fluorescent bulbs due to their high power efficiency and low operating voltage. These can be utilised optimally for emergency lamp and vehicle turning indication. Here are white LED based emergency lamp & turning indicator circuits for the purpose.
The project is available at: LED based emergency lamp
Audio controlled running lights
This mains operated audio controlled running light can be used in discotheques. The lamps glow in running sequence as per the sound of music. Of the ten AC lamps, only one lamp permanently glows if there is no sound. When music is played, light starts ‘running’ through the lamps.
This project is available at: Audio controlled running lights
This melody generator can generate various English and Hindi tunes as also instrumental effects. Various modes of melodies can be selected through DIP switches. Other advantages are high volume and volume control. There are 16 tunes stored in WR630173 including mera joota hai japani, mera naam chin chin chu, hare rama hare krishna, raghupati raghav raja ram and ramaiya vasta vaiya.
This project is available at: Melody generator
Festivals are always happening with us. If it’s not festivals, there is some family function. We have year-round family functions to keep us busy. How about in your next one, you handle the lighting system and show off some of those electronics skills? With this next project, you can nicely put some of those skills to use and be a core electronics engineer. All you need is an Arduino and few external components.
This mini project is available at: Fancy Lights Controller
Miniature strobe light
The circuit of a battery operated portable miniature strobe light, which can be constructed using readily available inexpensive components, is described here. An ordinary neon lamp is used here in place of the conventional Xenon tube. The whole gadget can thus be easily accommodated in a small cabinet, such as a mains adapter cover, with a suitable reflector for neon lamp to give a proper look.
This project is available at: Miniature strobe light
Dynamic display using LED strip
This next project designs a dynamic display that seems like an interesting prospective project. It describes a microcontroller-based dynamic display system using LED strips. Surface-mount device (SMD) LEDs are becoming popular because of their low power consumption and high brightness. Who knows when this might come in handy.
This mini project is available at: Dynamic Display Using LED Strip
This shooting game circuit is very simple, inexpensive and easy to construct. The game offers hours of fun and excitement. Just trigger an infrared electronic gun and there goes one invisible bullet hitting the bull’s eye, if timed properly. The target screen consists of a number of LEDs moving rapidly in a circular fashion. All the LEDs are red except one—the real target located in centre of the screen which is green. When a shot is fired by triggering the gun, all LEDs go off except one. If it happens to be the target (green LED) then you have made a hit which is indicated by lighting up of another green LED accompanied by a pleasing musical tone.
This project is available at: Shooting game
Presented here is a numeric display digital dice circuit. Timer IC 555 wired as an astable multivibrator produces pulses at about 48 kHz rate. These pulses are fed to pin 14 of the decade counter IC 7490. The oscillator is activated by depression of switch S1.
This project is available at: Digital dice
RF controlled robot
In this next mini project, we have a simple Arduino-board based robot that can be driven remotely using an RF remote control. This robot can be built very quickly in a small budget. The RF remote control provides the advantage of a good controlling range (up to 100 metres with proper antennae) besides being omnidirectional.
This mini project is available at: RF Controlled Robot
Experimenting with the fundamentals of electrical and electronics is always interesting. This next mini project demonstrates Faraday’s law of electromagnetic induction and gives musical output. The law talks about electromagnetic induction and production of electromotive force (EMF) across a conductor when it is exposed to a varying magnetic field.
This mini project is available at: Faraday’s Guitar
Sixth Sense media player
Sixth sense or gestural interface program is a popular term especially in robotics and wearable computers. This next mini project describes a hand-gesture-controlled media player. In such a media player, the user moves the hand in front of the camera. This project explains how to control the media player using a hand glove. It requires Windows Media Player, LabVIEW, Arduino and an accelerometer.
This mini project is available at: Sixth-Sense Media Player
We start the list off with a personal favourite. It describes a line-follower robot without microcontroller, making this suitable for non-electronics engineers as well. This robot follows a colour with the help of sensors. It is a simple project, which can be taken up as a classroom assignment. It lays the foundation for building your own behaviour-based (simulated) robot.
This mini project is available at: Simple Line-Following Robot
Hand video game
Playing space invaders on old black and white phones is a fond memory in many of our minds. How about bringing some of those back. This next project is a throwback to the time when we enjoyed. Let’s get to designing the once popular game using electronics. The fun part, after you are done designing, you get to play.
This mini project is available at: Hand Video Game
Fastest finger first
This one would be the one for students to design and implement in college competitions. This fastest finger project assigns a number to all the buzzers displaying the number of the team to press the buzzer first on a 7-segment display. Built around PIC micro controller this is just something we would all love in competitions as well.
This mini project is available at: Fastest finger first
Automatic switch-off battery charger
Presented here is an automatic switch-off battery charger based on a 555 timer IC. This smart charger automatically switches off when your rechargeable batteries reach the full charge. The circuit comprises a bistable multivibrator wired around timer IC 555. The bistable output is fed to an ammeter (via diode D1) and potmeter VR1 before it goes to three Ni-Cd batteries that are to be charged.
This project is available at: Automatic switch-off battery charger
Power bank for smartphones
With the increase in our dependence on technology, we also require suitable power options as well. This next project designs a power bank used for charging smartphones. The circuit uses two integrated modules and a lithium-ion battery. The first module is a lithium-ion battery charger and the second is a DC-DC boost converter module.
This mini project is available at: Power Bank for Smartphones
12V Battery absorb and float charger
Most battery chargers stop charging the battery when it attains its maximum charging voltage set by the circuit. This mini project guides on a charger that charges the battery at the absorption voltage. The charger changes the output voltage to float voltage on achieving maximum charging voltage. Hence maintaining the battery at that voltage. I surely know some people that could use this project, how about you?
This mini project is available at: 12V Battery Absorb and Float Charger
This pulse generator circuit is very useful while checking/operating counters, stepping relays, etc. It avoids the procedure of setting a switch for the required number of pulses. By pressing appropriate switches S1 to S9, one can get 1 to 9 negative going clock pulses, respectively.
This project is available at: Pulse generator
Solid-state relays provide the advantages of almost infinite switching, bounce-free operation, immunity to electromagnetic interference (EMI), higher operating speeds, low-voltage control, small package size and multifunction integration. Here we describe a DC operated solid-state relay that uses readily available components. It operates off a 3V DC battery or TTL compatible PWM input.
This project is available at: Solid-state relay
Food ordering system
Next we have a restaurant menu ordering system. Whenever you go to a restaurant, you have difficulty with interacting the wait staff. Language is just one of the barriers. The menu items and types of confusing names keep adding to it. How about if, the next time you go to a restaurant, there is an electronic menu? I know that excites you. You can build one and pitch it to a nearby restaurant owner as well.
This mini project is available at: Restaurant Menu Ordering System
Sequential timer for DC motor control
Most industrial processes require rotation of the motors in forward and reverse directions for desired periods. One good example is the automated bottle filling plant. The stop time of the motor is calibrated based on the time required to fill the bottle and the time before arrival of the next bottle. This mini project takes you through a similar journey in designing one by your very self.
This mini project is available at: Sequential Timer for DC Motor Control
Anti car jacking system
Consider this, a criminal stops your car by force and you are left with no option but to surrender the car. The criminal drives away your car but about 60 seconds later, the engine stops running on its own and won’t restart. Unable to use the dead vehicle, the perpetrator must abandon it. All this because you are an engineer and could design a carjacking system and were able to save your vehicle.
This mini project is available at: Anti-Carjack System
RF based multiple device control
This next project describes how to control electrical and electronic gadgets from a remote location using radio frequency (RF) transmission. An RF interface has a longer range making it suitable for usage. Sounds like a dream for lazy people, who won’t have to get up to switch off the lights at night. Possibly, you could install this system in your own house if you’d like.
This mini project is available at: RF-Based Multiple Device Control
Smart battery protector
The life expectancy of a battery dramatically reduces when it is discharged below the minimum recommended battery voltage. You must disconnect the load before discharging is complete. Otherwise, it can damage the battery or shorten its life. This disconnect function requires a battery voltage monitor with considerable hysteresis to prevent chattering in the disconnect switch. Chattering occurs as the battery voltage drops below threshold and then bounces back on load removal. This simple circuit outperforms the usual battery protectors. It uses shunt regulator IC TL431 for its simplicity and marvelous functioning.
This project is available at: Smart battery protector
How To Make A Business Card Flashlight
Here we make a business card useful by turing it into a business card flashlight, that people really do not want to throw away and use it as a piece of advertising. Essence of this project is that anyone can make it at home without any soldering, PCB and so on, as it requires none of these.
This project is available at: How To Make A Business Card Flashlight
Multimeter Test Leads from Scratch
If you are an electronics hobbyist and need to measure low currents and low voltages, you can buy any inexpensive multimeter. However, test leads of such meters are fragile. That’s what led me to make my own multimeter test leads from readily available material. These test leads cost you almost nothing as the required material, except wires, must be already available with most of you. Note that these test leads work fine for low voltages only.
This project is available at: Multimeter Test Leads from Scratch
USB MP3 Player
In this article you will find instructions to assemble and use the USB MP3 module supplied by Shenzhen Vire Silicon & Technology Co. Ltd, China. The module comes with a remote control also for users’ convenience.
This project is available at: USB MP3 Player
We compiled this list of mini project ideas for you. We always welcome new and interesting mini projects through [email protected]