Tuesday, August 2, 2016

Preparing your SD card for the Raspberry Pi

Your typical computer is running an operating system, such as Windows, OS X, or Linux. It’s what starts up when you turn your computer on and it provides your applications access to hardware functions of your computer. For instance, if you’re writing a application that accesses the Internet, you can use the operating system’s functions to do so. You don’t need to understand and write code for every single type of Ethernet or WiFi hardware out there. Like any other computer, the Raspberry Pi also uses an operating system and the “stock” OS is a flavor of Linux called Raspbian. Linux is a great match for Raspberry Pi because it’s free and open source. On one hand, it keeps the price of the platform low, and on the other, it makes it more hackable.

The SD card is important because this is where the Raspberry Pi keeps its operating system and is also where you will store your documents and programs.  The Raspberry Pi will not start without a properly formatted SD Card, containing the bootloader and a suitable operating system.This is very different from most computers and it is what many people find the most daunting part of setting up their Raspberry Pi. It is actually very straightforward—just different!
Warning! When you write the Raspberry Pi image to your SD card you will lose all data that was on the card.

The following instructions are for Windows users.Linux and Mac users can find instructions at : www.raspberrypi.org/downloads
1. Download the Raspberry Pi operating system
The recommended OS is called Raspbian. Download it here
2. Unzip the file that you just downloaded
a) Right click on the file and choose “Extract all”.
b) Follow the instructions—you will end up with a file ending in .img .This .img file can only be written to your SD card by special disk imaging software, so…
3. Download the Win32DiskImager software
a) Download win32diskimager-binary.zip (currently version 0.6) from: https://launchpad.net/win32-image-writer/+download
b) Unzip it in the same way you did the Raspbian .zip file
c) You now have a new folder called win32diskimager-binary . You are now ready to write the Raspbian image to your SD card.
4. Writing Raspbian to the SD card
a) Plug your SD card into your PC
b) In the folder you made in step 3(b), run the file named Win32DiskImager.exe
(in Windows Vista, 7 and 8 we recommend that you right-click this file and choose “Run as administrator”). You will see something like this:
c) If the SD card (Device) you are using isn’t found automatically then click on the drop down box and select it
d) In the Image File box, choose the Raspbian .img file that you downloaded
e) Click Write
f) After a few minutes you will have an SD card that you can use in your Raspberry Pi
5. Booting your Raspberry Pi for the first time
a) Follow the Quick start guide on page 1
b) On first boot you will come to the Raspi-config window
c) Change settings such as timezone and locale if you want
d) Finally, select the second choice: expand_rootfs and say ‘yes’ to a reboot
e) The Raspberry Pi will reboot and you will see raspberrypi login:
f) Type: pi
g) You will be asked for your Password
h) Type: raspberry
i) You will then see the prompt: pi@raspberry ~ $
j) Start the desktop by typing: startx
k) You will find yourself in a familiar-but-different desktop environment.
l) Experiment, explore and have fun!

Friday, July 22, 2016

Mind Uploading

Aside from artificial intelligence and robotics, there is a third field that will start showing incredible promise in coming decades. We will begin to integrate computer systems into our brains. Computers will become more and more integrated to our brains until we eventually dispense with the old fashioned goo that is our biological brains and move forward at accelerating rates with our fully artificial brains. We will have, in essence, become the robots. This concept is called Mind Uploading.

Simply speaking, mind uploading is a science fiction concept of copying one's mind into an artificial body or computer. It is a popular term for a putative process by which the mind, including memories, personality, consciousness, etc of a specific individual is transferred from its original biological brain to another operating substrate.
Despite of the tremendous and miraculous achievements of we humans, being in the most of the scientific field and research area, mind uploading is still the scientific challenge for human race. This technology will radically alter society in many ways, as science fiction authors have begun to illustrate. With this rapid development in technology, the day might not be that far away when this science fiction turns into reality. Once it is possible to move a mind from one substrate to another, it is called Substrate Independent Mind (SIM). SIM is a field of research which seeks to understand the brain and the nervous system of a wide range of organisms including humans, in order to facilitate emulation of these organisms in an artificial substrate, for example, a computer professor.

In order for progress to be made in the field of SIM, advancements in many key technologies and research areas are required. Some of them are nanotechnology, biotechnology, brain imaging, neuroscience, artificial intelligence, computational hardware and architectures, cognitive psychology and philosophy.
The technology most commonly associated with mind uploading is Whole Brain Emulation (WBE), emulation as when one type of processor is emulated in software on top of another type of processor. Whole Brain Emulation can be equivalent to neural prosthesis of the whole brain. Neural Prosthesis (NPs) are assistive devices that restore functions lost as a result of neural damage. It can substitute a motor, sensory or cognitive modality that might have been damaged as a result of an injury or a disease.

The terms "whole brain emulation", "mind uploading" and "substrate independent minds" have been used informally in recent years to describe a set of related ideas regarding hypothetical possibilities for transferring or emulating the functioning of a human's brain or "mind" on a synthetic substrate. 
The recent breakout in the research was Synaptic Electronic Circuit that learn and forget like neural processes. Rui Yang, Kazuya Terabe and colleagues at the National Institute for materials Science (NIMS), and the International Center for Materials Nanoarchitectonics (MANA) in Japan and at the California NanoSystems Institute/UCLA have developed "nanoionic" (processes connected with fast ion transport in all-solid-state nanoscale systems) devices capable of a broad range of neuromorphic and electrical functions. Such a device would allow for fabrication of on-demand configurable circuits, along memories, and digital-neural fused networks in a single device architecture.

Synaptic devices that mimic the learning and memory processes in living organisms are attracting interest as an alternative to standard computing elements to help extend performance beyond current physical limits. However, artificial synaptic systems have been hampered by complex fabrication requirements and limitations in the learning and memory functions. The device is based on a platinum-tungsten trioxide (WO3-x) device using oxygen ions migrating in response to voltage sweeps. Accumulation of the oxygen ions at the electrode leads to Schottky-diode like potential and resulting changes in resistance and rectifying characteristics. The stable bipolar switching behavior at the platinum-tungsten trioxide based device is attributed to the formation of a conductive filament and oxygen absorbability of the platinum electrode, they mimic. The researchers noted that the device properties -- volatile and non-volatile states and current fading following positive voltage pulses are similar to neural behavior that is, short and long term memory and forgetting processes. The device was found to possess a wide range of time scales of memorization, resistance switching, and rectification varying from volatile to permanent in a single device.

This technology will radically alter society in many ways, as science fiction authors have begun to illustrate. With this rapid development in technology the day might not be that far away when this science fiction turns into reality. Once it is possible to move a mind from one substrate to another, it is called a Substrate Independent Mind. If such breakthrough occurs repeatedly in field of mind uploading then the day is not far that all the sci-fi like Avatar, Transcedence, etc come into reality. The pros and cons of this research will be however known after the real practice in near future.

Wednesday, July 20, 2016

Forced Perspective

The fascination for some things never fades away. Considering humanity as a whole, the fascination for representation and expression of ourselves though "forced perspective" has been one of many such things. The earliest records of this can be found during the Roman Era when technology was limited. The interior of Roman Emperor Constantine's Aula Palatina palace is one of the examples, built in around 300 A.D. Its mystery is unraveled later in the article. In addition, forced perspective photography in which objects that are far from us are smaller relative to the ones that are closer.

Forced perspective is one of the methods used to create optical illusion. It exists because of an almost a defect to working of human visual system. Human mind has a natural desire to interpret any 2-D drawing or picture as a projection of  a 3-D object in a plane. Our visual perception processes information about objects we see on the basis of light received from them. So, objects that are far from our eyes are smaller relative to the ones that are closer. But when the information given to our eyes is limited by forcing it to process information based on a single perspective, looking at different parts of the object makes us reconsider the 3-D nature of the object, which confuses the mind. Thus, an optical illusion is created by the method of forced perspective. This can be clarified from the example of Penrose triangle shown below.

Fig: A Penrose Triangle

A penrose triangle has its every 3rd side situated at an angle to the plane containing any 2 of its sides. By forcing us to interpret the information about the triangle only from one perspective , it makes us realize the impossibility of such a structure to exist.

There are many interesting applications in both contemporary and modern culture. Architectural accomplishments, ranging from times of Roman era to the present that has been adopting this method to surpass limits of creation to create 'Impossible Architecture'.
Constantine's palace is one of such examples where the length of the palace is magnified by optical illusion, giving an impression of the palace being much longer than it actually is, when seen from the entrance.

In recent times, forced perspective has found applications in Film making, Photography, Videography and more recently typography and gaming.
In Filmmaking, forced perspective techniques have been widely used ranging from low-budget B movies to Mega budget movies like the Lord of the Rings series, Harry Potter series, Inception, etc. A lot of this was used in the Lord of the Rings to make characters like Grandalf, a giant and like Frodo and Bilbo, dwarfs when in reality their height differs only by 5 inches. Similar dwarf-giant technique has been used in Harry Potter. Forced perspective techniques have also been widely used and experimented in photography and videography. In a music video, "The writings on the Wall" by a rock band, OK Go, multiple instances of this technique has been used. This is also widely being adopted as a presentation technique for the unique view/perspective about things.

Tuesday, July 19, 2016

Cognitive Radio

An Approach to Spectrum Management

We are all quite familiar with the enormous capacity of the universe that makes it a massive storehouse of energy from where humans have been continuously extracting assets to somehow build a human friendly world. One of them is finite and increasingly precious resource - the electromagnetic spectrum.
The radio spectrum is an entity of the electromagnetic spectrum corresponding to radio frequencies in the range of around 3 KHz to 300 GHz that help us transmit information through air. Radio spectrum enlarges the definition of natural resources to use air as a medium of communication, so like any other resource, it has a fixed capacity at any given time and the use of it by one limits the use of it by others. The dependence in radio communication in one form or the other has grown dramatically in recent years, and the growth in the number and variety of applications, many of them bandwidth hungry, and the huge expansion in user expectations place ever-increasing demands on radio spectrum.

Fixed and mobile communications, sound and television broadcasting, aviation, railway and maritime transport, defense, medical electronics, emergency services, remote control and monitoring, radio astronomy and space research, as well as many other applications, make use of radio spectrum. Because the radio spectrum offers the instantaneous and direct way of communicating across space, congestion has greatly increased abating its efficiency.
                 Congestion, here called interference results, when spectrum is overtaxed, just as pollution arises in a crowded highway or in a body of water that receives effluents. In order to avoid interference, spectrum holes need to be sensed. The under-utilization of the electromagnetic spectrum leads us to think in terms of spectrum holes, which is a band of frequencies assigned to a primary user, but, at a particular time and specific geographic location, the band is not being utilized by that user. Spectrum utilization can be used significantly by making it possible for a secondary user (who is not being serviced) to access the spectrum hole unoccupied by the primary user at the right location and time.

Cognitive radio, inclusive of software-defined radio, has been proposed as a means to promote the efficient use of spectrum by exploiting the existence of spectrum holes. Cognitive radio is a popular technology as it is based on software to define the wireless sensing techniques which further enhances the spectrum utility rate evidently. Software radio provides an ideal platform for the realization of the cognitive radio. Software radios are emerging as platforms for multiband multimode personal communication systems. Radio etiquette is the set of RF bands, air interfaces, protocols and spatial and temporal patterns that moderate the use of the radio spectrum. Cognitive radio extends the software radio with radio-domain model-based reasoning about such etiquettes. Cognitive radio enhances the flexibility of personal services through a radio knowledge representation language. This language represents the knowledge of radio etiquettes, devices, software modules, propagation, networks, user-needs, and application scenarios in a way that supports automated reasoning about the needs of the user.

The concept of cognitive radio is originated from radio sensing and learning; recognizes and allocates spectrum opportunity; realizes spectrum opportunity, and cognitive radio utilizes the intelligent sensing method to acquire the spectrum usage information and environment parameters, then chooses the most feasible network or the spectrum reconfigurable network architecture.

Cognitive radio is an intelligent wireless communication system that is aware of its surrounding environment (i.e. outside world), and uses the methodology of understanding-by-building to learn from the environment and adapt its internal states to statistical variations in the incoming RF stimuli by making corresponding changes in certain operating parameter (e.g. transmit-power, carrier-frequency, and modulation strategy) in real-time, with two primary objectives in mind:

  • Highly reliable communications whenever and wherever needed.
  • Efficient utilization of the radio spectrum. 

Monday, July 18, 2016

Local Apps To Watch Out For in Nepal

1. eSewa


The first online payment gateway in Nepal provides services like paying utility bills, buying movie tickets, airline tickets and even recharging your phone right from your home. So, whether you are a busy CEO or a lazy couch potato, this app will definitely make your life easier.

Developer: f1 soft


2. Yellow


Ever gone hungry just because you could not find a decent place to eat? Now, with the yellow app, find over 500 great places within Kathmandu to eat and celebrate. Also, find great deals and info about upcoming events. And try really hard not getting overwhelmed by the incredible design.

Designer: Yellow Nepal

3. Kantipur (KMG)


Read Nepal's largest selling English and Nepali dailies and weeklies, watch Kantipur TV, get latest news updates, listen to Kantipur FM, watch model profiles and what not. This app covers the best of Kantipur Media and has even made reading newspaper on paper feel like it's 1995.

Developer: KMG

4. Birthday Forest



Gift someone a tree on their birthday, anniversary or even for no reason at all. An award winning non-profit, you will receive longitudes and latitudes of your tree.
P.S, it's one more thing for you to boast in social media.

Developer: Birthday Forest

5. Nepal Sutra


If you have been following Nepali app history, this app needs less of an introduction. A regular travel app plus a feature called 'find travelling buddies' helps you find fellow like-minded travellers on the go, next time you're travelling, don't forget to take this personal travelling guide with you.

Developer: Candid Services

6. nLocate


Locate everything around you: Whether it be a bank, hospital, ATM, government office, coffee shop, you name it - you can find almost every corner around the metropolis. Of course, you can do that with the google maps but the purpose here is to find more relevant information like phone numbers and local experience. Also watch out for a major performance and UI update.

Developer: Nepways

7. IFA Krishi


This app provides the major crop and animal disease information and its medical solutions. It also lists out the fertilizer requirements in different plants. It also provides best quotations in the market for getting the right value for your reaping. Another feature is its 14-day weather forecast of major cities of Nepal to help the farmers better their farming process.

Developer: Innovation Web Groups

8. Amakomaya


 To what extent can we owe an app? Can it save someone's life? Apparently, now it can. This app increases the outreach of information related to maternal health issues to rural pregnant women. With interactive videos and infographic dos and don'ts you cannot just save a life but save several lives at once.

Developer: Yagiten Pvt. Ltd




Saturday, July 16, 2016

Raspberry Pi

People were skeptical of the Raspberry Pi when it was first announced that a credit-card sized computer for $35 sounded like a fantasy. Which is why, when it started shipping, the Raspberry Pi created a sensation of excitement. The demands for the minicomputer was outperforming what the foundation had expected. So, what is about the Raspberry Pi that tests the patience of a hardware-enthusiast?
One can use this device to watch videos, surf the web, or to hack, learn and make an open source project with the board. The Raspberry Pi is a flexible platform with tremendous support for fun, utility and experimentation. Here are just a few different ways how a Raspberry Pi can be used.

General Purpose Computing
In fact, Raspberry Pi is itself a computer and you can use it as one, make the pi boot into a graphical desktop environment with a web browser, which is lot of what we use computers for these days. In addition, install variety of software like LibreOffice productivity suite for working with documentation and spreadsheets.

Learning to Program

Raspberry Pi is meant as an educational tool to encourage young generation to experiment with the computers. It comes pre-loaded with interpreters and compilers for Python and Scratch (graphical programming language from MIT).
But you are not limited to Python and Scratch, you can write programs for Raspberry Pi in many different programming languages like C, Ruby, Java and Perl.

Project Platform

The Raspberry Pi distinguishes itself from a regular computer not only in its price, size, processor and architecture, but also because it has the ability to integrate with electronic projects.

Media Center

The Raspberry Pi has both HDMI and composite video outputs, it's easy to connect to televisions. It has enough processing power to play full screen video in high definition. To enable a Raspberry Pi as a media center, XBMC (Xbox Media Center) have ported their project to the Raspberry Pi. XBMC can play many different media formats and its interface is designed extremely friendly with large buttons so that it can be easily controlled from the couch.

Raspberry Pi, a microcomputer is based on the ARM processors that uses a family of instruction set architectures based on a Reduced Instruction Set Computing (RISC) developed by a British company, ARM Holdings.
The term RISC abbreviates Reduced Instruction Set Computing. It is focused on a small set of instructions which simplifies the hardware design and improves the processor performance.

Where can you buy it from?

In the context of Nepal, Raspberry Pi can be purchased from Himalayan Solution Industry, Gyaneshwor (Contact: 9841827527).

Despite being a $35 microcomputer, it is a little expensive in Nepal. But, if you have contact with friends and family abroad, then shipping via online shopping stores like Amazon would be sensible and more economical.

Source: Electronics Project Club Magazine (KEC)

Wednesday, July 13, 2016

Wired Spy Bug


 Circuit Diagram:


This spy bug circuit will help you to listen to a conversation without being noticed or simply when you want to spy on a person. The circuit is constructed using a Mic, an Amplifier and a Speaker. The device can be wired or wireless depending on the comfort of your design. The device is built around an OpAmp IC741. It consists of a NPN transistor Q1(2N222) and a PNP transistor Q2(2N2907) connected in Push-Pull configuration.


This circuit can be divided into three sections for better understanding. First part is the Receiver, which is built using an Electric Microphone (Mic) and a Resistor R1. The microphone converts the sound into electrical signal and R1 adjusts the sensitivity of the Mic. The resistor R2 serves as a volume control and capacitor C1 is used to remove the dc component of the signal.

Next comes the pre-amplifier stage which is built using the OpAmp IC741. The IC is wired as an Inverting amplifier and hence the input signal is passed through the inverting terminal of the IC. The positive terminal or the non-inverting terminal is biased using the voltage divider R3 and R4. The resistor R5 is used to provide the negative feedback to the Opamp which in turn controls the gain of the Opamp.

The final stage comes to the amplifier built using the transistors Q1 (2N222) and Q2 (2N2907). These transistors are connected in Push Pull configuration which implies that one of the transistors amplifies the positive half cycle of the input and the other amplifies the negative half cycle. Collectively, we obtain an amplified 180 degree out of phase signal from the amplifier. The signal is then passed through the capacitor C2 to filter out any dc components and then finally to the Speaker.



Nanotechnology refers to the technology which deals at the size of 
nano meters ( about 1-100 nm). Nanotechnology is the study of all
aspects of science and technology in a very precised size, i.e it deals with atoms and molecules of the particles. In Nepal, we mostly get used to the technology at the micro level such as micro controllers, microprocessors and so on. Nanotechnology encompasses the understanding of the fundamental physics, chemistry, biology and technology of nano metric scaled objects.

 Evolution of Nanotechnology:

Every now and then we hear about the famous talk "There's plenty of room at the bottom", entitled by a famous physicist Richard Feynman. This phrase was talked way before the term "Nanotechnology" was used. The development on the field of nanotechnology did not start until 1981, when a tunneling microscope was invented which could even distinguish a single atom.

Interestingly, if a marble is considered to be the size of a nano meter, then one meter would be the size of the whole earth.

So, there's an unprecedented multidisciplinary convergence of scientists dedicated to the study of a world so small, we can't see it, not even with a light microscope.

Importance of Nanotechnology:

Let me ask you a question:

What's so small that you can't see it, but it's smart enough to run your iPad or stop cancer?

- If your answer is a microscopic person who is a doctor with a part time job of being an electronics engineer, then you're not absolutely wrong. But, the answer is "nanotechnology".

In most of the developed countries, Nanotechnology has found a place in consumer products, medical treatment, the food industry and so much more. In fact, it's becoming increasingly harder to keep track of where nanotech isn't. And the truth is that the technology's potential is nowhere near being reached, not even in the highly developed countries. Many of the big breakthroughs are still being worked out in laboratories. And only some of the simplest forms of nanotechnology have really come to the marketplace.

Some of the best examples that nanotechnology exists today are:
  • Molecule Printers
  • Stretchable Gold
  • Artificial Muscles
  • Stain-Repellant Fabric Coating
  • Plastic that bleeds and heals itself
  • Electricity Generating Viruses

Difference Between Microcontroller and Microprocessor

The term microprocessor and microcontroller have always been confused with each other. Both of them have been designed for real time application. They share many common features and at the same time they have significant differences. Both the IC’s i.e., the microprocessor and microcontroller cannot be distinguished by looking at them.  

They are available in different versions starting from 6 pin to as high as 80 to 100 pins or even higher depending on the features.

Difference between microprocessor and microcontroller
Microprocessor is an IC which has only the CPU inside them i.e. only the processing powers such as Intel’s Pentium 1,2,3,4, core 2 duo, i3, i5 etc. These microprocessors don’t have RAM, ROM, and other peripheral on the chip. A system designer has to add them externally to make them functional. Application of microprocessor includes Desktop PC’s, Laptops, notepads etc.

But this is not the case with Microcontrollers. Microcontroller has a CPU, in addition with a fixed amount of RAM, ROM and other peripherals all embedded on a single chip. At times it is also termed as a mini computer or a computer on a single chip. Today different manufacturers produce microcontrollers with a wide range of features available in different versions. Some manufacturers are ATMEL, Microchip, TI, Freescale, Philips, Motorola etc. 

Microcontrollers are designed to perform specific tasks. Specific means applications where the relationship of input and output is defined. Depending on the input, some processing needs to be done and output is delivered. For example, keyboards, mouse, washing machine, digicam, pendrive, remote, microwave, cars, bikes, telephone, mobiles, watches, etc. Since the applications are very specific, they need small resources like RAM, ROM, I/O ports etc and hence can be embedded on a single chip. This in turn reduces the size and the cost.

Microprocessor find applications where tasks are unspecific like developing software, games, websites, photo editing, creating documents etc. In such cases the relationship between input and output is not defined. They need high amount of resources like RAM, ROM, I/O ports etc. 
The clock speed of the Microprocessor is quite high as compared to the microcontroller. Whereas the microcontrollers operate from a few MHz to 30 to 50 MHz, today’s microprocessor operate above 1GHz as they perform complex tasks.

Comparing microcontroller and microprocessor in terms of cost is not justified. Undoubtedly a microcontroller is far cheaper than a microprocessor. However microcontroller cannot be used in place of microprocessor and using a microprocessor is not advised in place of a microcontroller as it makes the application quite costly. Microprocessor cannot be used stand alone. They need other peripherals like RAM, ROM, buffer, I/O ports etc and hence a system designed around a microprocessor is quite costly.

3D Printing

3D Printing

3D Printing, also known as additive manufacturing is an art of turning a 3D design on your computer into a solid object. It's a sort of extension of Computer Aided Design, which has so transformed professions such as engineering and architecture.

You draw the design on a computer screen, and the data then drives a machine which spreads thin layers of plastic or metal powder on top of each other. Each layer is solidified by a sort of laser welder or sinterer; at the end of the process you blow off the unsitered powder and the object you drew on the screen is transformed into complex, intertwined three dimensional reality.

The inception of 3D printing can be traced back to 1976, when the Inkjet printer was invented. In 1984, adaptations and advancements on the inkjet concept morphed the technology from printing with ink to printing with materials when the founder of 3D printing, Charles Hull invented stereolithography, a printing process that enables a tangible 3D object to be created from digital data. The technology is used to create a 3D model from a picture and allows the user to test design before investigating in a larger manufacturing program.

In spite of the fact that 3D printing was invented in the 1980s (really), only recently has it become accessible for anyone besides huge corporations. Since, it has become available for just about anyone to use, it has exploded in popularity. It seems like prices go down, quality goes up, and more materials are available every day. It's a good time to be a maker and better techniques and materials are turning 3D printing into manufacturing operations so called addictive manufacturers, as opened to the cutting and grinding and sawing that has typified engineering up to now.

In theory, it seriously reduces the need for factories, production lines, warehouses, transport around the world from great production hubs. Many things can be printed up for digital instruction in a neighborhood print shop, and carried home under your arms, rather than shipped in a container of loads around the world. This is a very big step. It individualizes industries which until now have been dominated by mass production. In theory, every single product can be different, made to measure, as operators learn how to make things with mixed materials on larger and larger scales.

As a proof of its versatility, in a few decades, 3D printing has already seen the use in the field of architecture, construction (AEC), industrial design, automotive, aerospace, military, engineering, dental and medical industries, biotech (human tissue replacement), fashion, footwear, jewelry, eyewear, education, geographic information systems, food and many other fields.

Flash Based File System

A need of the advancement in storage technology

Gone are the days where we had clicking noises on our desktops, laptops and many more machines. Now is the age of silence yet with incredible performance. Let us talk about the emerging technology of management of files.

Last Friday, I came up with a search on my local drive to find a song and voila, I got it in a certain location. The file system thing has a big history and comes up from the old Unix days. These file systems are actually an abstraction that are made for the ease of the user, but in reality there is nothing called a file. The file in real is actually the abstraction that separates certain sectors or blocks to store a digital content and creates the link on a table where the entries are placed so that it can be shown to us as a file.

We all have heard about FAT and NTFS file systems. These file systems are actually made for the spinning disc based drives. We have had days when we had floppies, zip drives and hard disk drives, where we had spindle that could drive a platter of discs where we used to store data. Since the whole system was based on a revolving disc technology we required a very efficient file system to handle the content on those discs, where we came up with the idea of cylinder, head and sector system. We again managed to convert such CHS system into logical block addressing technique. But that's a tale now. We have landed into a new era of storing digital content. Semiconductor memory chips are now cheaper and less power consuming as we have advanced so much in the fabricating technology. So the days of SSD (Solid State Drives) are on the information highway already. Now for the very efficient throughput of the flash based devices we need a very new file system that can handle these flash blocks efficiently and effectively. Here we propose a block-based file handling system.

A solid-state drive is made up of arrays of flash chips controlled by and addressing technique and a very efficient and fast microcontroller. These flash chips are NAND chips or nor chips depending upon the manufacturing technology. NOR chips do offer random access but doesn't offer random rewrite and erasure. NAND chip offers only sequential access.

Beside these features, there are certain limitations to the flash based memory. These limitations of flash based memory make us to develop and use a block based file system which has a good support for flash based systems which can ensure for long run and less error on the overall system. The limitations are :

i.  Block Erasure
ii. Memory Wear

Source: Electronics Project Club Magazine

Friday, July 8, 2016

Serial Monitoring

Serial Monitoring is done in Arduino (software). So, before you can check whether your sensor is working fine or not, you need to install the arduino software. If you don't have arduino, you can download it from here.

Once you install arduino in your computer, you need to connect the sensor pins to the arduino hardware and the hardware to the computer. The sensor pins give an analog input to the arduino, i.e the output from the sensors are variable as they sense differently in different conditions. For example, if they sense the white color, they may send a small voltage, while on the other hand, if they sense something darker, they may send a comparatively greater voltage depending on the configuration of your sensor.

So, make sure that you connect the sensor pins to the analog pins of arduino (A0 - A5). Since, there are five sensor pins in your sensor board, you can connect them to respective pins A0 - A4. Also, make sure that you give a 5V power supply to your sensor board either by an external battery or through the arduino itself. After you connect all the pins, your sensor board is ready for serial monitoring.

Now, what you need to do is, write a program in arduino to monitor your sensors. If you are familiar with the programming language C, then you will not have difficulties coding in arduino. Both are pretty much the same with slight differences. Here is a screenshot of the code that is going to help you for serial monitoring. I have written down some comments too, so that you understand the code precisely.

Setting Up the modes for the analog pin and Baud Rate for Serial Monitoring

Taking input from the sensors and printing it in the Serial Monitoring Window

If the images are not clear, then you can download them from here.

To summon up the program, basically what we are doing is, we set the analog pins A0 - A4 in INPUT Modes, take the input from the sensors and print them in the serial monitor window of arduino. To open the serial monitor window, press  "Ctrl + Shift + M".

Now, you can see the values given by your respective sensors in the serial monitor window. This is the time when the POT (potentiometer) connected to the sensor board comes to use.
Make sure you have a white paper below all your IR sensors and watch the values in the serial monitor window. Now, try to make all the values to a similar range by rotating the top of each POT in either direction. For example, if the 1st sensor shows 308, then try to adjust the values of all other sensors at around (290 - 320) by rotating the POT for each.

Once you adjust a similar range of values for all the sensors, replace the white paper underneath with a black one and then observe the values again. If the values differ from the previous values by a fine range (about a difference of 400-500), then it confirms that your sensor board is working perfectly fine.
Also, make sure that after you replace the white paper with a black one, the values given by all five sensors are within a range just like the previous time.

NOTE: Here, the range of the values given by the sensors is between 0 to 1023. This is because we are using a microcontroller that is a 10 bit microcontroller. So, the total number of values possible is 2^10 (i.e. 1024).

Thursday, July 7, 2016

Project Loon

In today's generation internet has undoubtedly an enormous impact on our lives, But still there are 5 billion people that is 2-3rd of the worlds population without internet access, because for every one person in the world that can get online, there are two that cant. So Google X has launched a project called project loon, a balloon powered internet for everyone with a mission of providing internet access to the people in the rural and remote areas.
The project uses a network of high altitude balloons flying around the globe on the stratospheric winds at an altitude if 18 km to create an aerial network with up to 4G-LTE speeds. So these balloons floats in the stratosphere twice as high as airplanes and the weather to beam internet access to the ground.

In the stratosphere there are many layers of wind and each layer of wind varies in direction and speed. project loon uses software algorithms to determine where it needs to go,then moves each one into a layer of wind blowing in the right  direction. They are steered via solar power and ensured that they catch the right winds to keep them together and give good internet coverage on the ground. The patterns of the balloon sailing in the wind is shaped so that when one balloon leaves, another balloon is set to take its place. They communicate with a specialized internet antennas on the ground, then each talks to its neighboring balloon and back to the ground station which is connected to local internet service provider.

This creates one large communication network in the sky. The antennas have been designed to receive signals from project loon only to achieve high bandwidth over the long distance involved.

As the balloons floats at high altitude there may arise problems of air pressure, damage from UV radiation and changes in weather conditions. But the balloon envelop is carefully designed to withstand these conditions.
The balloon's envelope is made from polyethylene plastic. Each balloons electronics are powered by an array of solar panels, These solar array is placed at steep angle to effectively capture sunlight so that it can produce power in full sun to keep the electronics running and also store power in the lithium ion batteries so balloon can operate in night.
On 16th June 2013 Google began a pilot experiment in New Zealand where about 30 balloons were launched. Google has tested its balloon powered internet access venture in Piaui, Brazil and in Sri Lanka.  

Schematic For Infrared Sensor Board

Schematics for Infrared Sensor

For making a sensor board using Infrared sensors, you are going to need the following components.

  • Infrared Transmitters and Receivers ( 5 each )
  • LED for an indicator ( 1 pc )
  • 0.4k Resistors ( 10 pcs )
  • 22k Resistors ( 5 pcs )
  • 5k Potentiometers ( 5 pcs )
  • Male headers ( 7 Headers )
  • PCB Matrix Board
After you get your matrix board, you will need to solder the above items in the board by looking at the given schematics. For better efficiency, you can start soldering the components in the following order.

  1. Solder all the 0.4k resistors as shown by connecting a line for the positive terminal of the source.
  2. Connect the respective Infrared Transmitters (IR1 - IR5 ) with the resistors along with a LED at the end ( used as an indicator for the board ) .
  3. Now, connect the negative ends of the IRT ( Infrared Transmitters ) to a line which connects the negative terminal of the battery.
  4. Similarly, connect the negative ends of all the IRR ( Infrared Receivers ) to a single line which connects them to the negative end of the battery.
  5. After that's done, connect the 22k resistors in a 45 degree angle with the positive end of each of the IRRs as shown in the diagram.
  6. Make sure you buy three terminals POT (Potentiometers) that are compatible to your board. Solder the single end of the POT to the 22k resistor and one of the bottom two legs to a single line, which in the end gets connected to the positive terminal of the battery. Solder everything as shown in the figure by examining the circuit carefully.
  7. Finally, you have to do one more thing that is not illustrated in the figure. Bring out wires from the ports that are named as label(1-5) and connect them to 5 male headers at one side of the board. Similarly, connect two headers at the terminal ports of the battery so that it is easier to connect and disconnect the battery at your own will.
After you get finished with your soldering and the connecting stuffs, your circuit board or the sensor board might look like this in the pictures given below.

Artificial Muscles


What is it??

Artificial Muscle is a generic term used for materials or devices that can reversibly contract, expand, or rotate within one component due to an external stimulus (such as voltage, current, pressure or temperature). The three basic actuation responses – contraction, expansion, and rotation – can be combined together within a single component to produce other types of motions (e.g. bending, by contracting one side of the material while expanding the other side).

Why is it important?

1.Artificial muscle technologies have wide potential applications in biomimetic machines, including        robots, industrial actuators and powered exoskeletons.

2. Artificial muscles offer a combination of light weight, low power requirements, resilience and agility for locomotion and manipulation.

3. Future EAP devices will have applications in aerospace, automotive industry, medicine, robotics, articulation mechanisms, entertainment, animation, toys, clothing, haptic and tactile interfaces, noise control, transducers, power generators, and smart structures.


Line Following Robot With Manual Control

Line Following Robot With Manual Control:

Line Following Robot

Components Required:

  • Arduino UNO
  • A Chasis for your BOT ( You can build it yourself )
  • Two DC Motors along with Tires
  • L293D Motor Driver
  • Caster Wheel
  • Infrared Sensors ( Transmitter and Receiver - 5 each )
  • 5K Potentiometers for PCB
  • 9V Battery for Power Supply
  • Bluetooth Module for Wireless Remote Control
  • Analog Joystick or Push Buttons for Wired Remote Control
  • Male and Female Connectors ( 10 each )


Designing the Body:

Before configuring any Hardware or Programming, you should take care of the chasis (body of the robot) that you are going to use. Once you get ready with your chasis, connect the two motors adjacently on two sides of the chasis and wind them with the help of zip ties or whatever you are comfortable with (make sure that the motor is tied tightly enough with the chasis). After that, connect a caster wheel at the front end of the chasis to make a free wheel, so that your bot can move sideways freely with the help of just two motors.

After you get the design of your bot ready, here comes the critical and the most important part. To build a line following robot with manual control, you have to deal with two parts basically: The Automated Part and The Manual Part.

The Automated Part:

To begin the automated part, you must first design the sensor of your robot. You can build the sensor yourself by buying the infrared sensors and the potentiometers or you can easily get a "digital sensor" from the market which will work even better with your project. If you want to learn to build a sensor board yourself with the help of infrared sensors, click here.

Once you get done with your sensor board, you need to check whether it does work with the design of your arena or not. For this, you need to have some knowledge about serial monitoring.

Serial Monitoring helps you to check whether your sensor is working correctly or not. So, after you get done with your sensor board, you move on to the next part, i.e. the manual part.

The Manual Part:

You can control a robot manually with the help of a remote control, which can be wired or wireless. Making the manual part of the robot is not as complicated as the automated part. So, you can handle this with more comfort.


If you want to make a wired remote control for your robot which can be a cheaper option, then you can deal with analog joysticks or the push buttons. Another thing that you can try is a movable potentiometer which can work like a joystick. Once you build your remote with any of the above components, you can connect the wires to the arduino digital pins directly. You need to make sure that you send either a high voltage signal or a low voltage signal to command your bot accordingly.
For example: If you are using 4 push buttons, then each button should send a '1' (HIGH) signal to an arduino digital pin so that you can process the particular signal to perform the operation on your robot.


Making a wireless remote  control for your bot is comparatively easier, but a little expensive. All you need is a bluetooth module and a smartphone. You connect the bluetooth module to an analog pin of the arduino and serial monitor the input from your smartphone to the arduino, whenever you press any button on the app of your smartphone. Then, by analyzing the different values received by the module from your smartphone by pressing different buttons on your phone, you write a program to perform the respective task using the if...else conditions.

How to switch between the Automatic and the Manual part?

Most people get confused when it comes to switching between the automatic and the manual part in their program. Well, it's quite simple with a technique that I generally use. You can also use the Interrupt technique to switch your robot, but I prefer using a separate digital pin to do that.

Assign a separate digital pin and connect a button to the pin if you are using a wired remote. As soon as you give a high signal to the pin, make your program runs the automatic part. You can also use a separate pin for the manual part which is activated when you give a high voltage to that pin. This might get confusing to you, but you will eventually get to the point that I'm trying to explain, once you get done with the programming part that we discussed earlier.

For the wireless remote, it is quite simple. You don't even need to use a different pin for this purpose. Assume a button in your phone application that you want to use to change the robot from being autonomous to a manually controlled one. Check its value using the serial monitor and assign it in your program for doing the exact operation that you want when the button is pressed. Do the exact same with another similar button when you want to switch from manual to the automatic part.

That is it. Well, I must say, it's easier to read a blog about building an automatic robot, but it is a challenging task to build it on your own. You will eventually get tangled with a lot of problems, once you get going with your project. But remember one thing, "Every problem has different solutions to it".

I wish you luck to make your project a success.

Keep sharing. Keep building.

Thank You.

Saturday, July 2, 2016

Electronic Eye

Electronic Eye:

Components Required:

  1. Regulator 7805
  2. Resistors:  R1=100k ohm, R2= 1k ohm, R3=100 ohm, R4=220 ohm, R5=820 ohm
  3. Capacitors: C1=10 micro-farad, C2= 1 micro-farad
  4. Diodes: D1, D3, D4= 1N4007
  5. LED Diode D2
  6. Light dependent resistor LDR
  7. Buzzer
  8. Transistors Q1 and Q2= BC547


An electronic eye is a simple circuit which operates the buzzer when a shadow falls on it.  Initially a 9V battery is connected to the diode D1 which is in forward biased condition. This diode protects the circuit form negative voltages by allowing the current to flow in only one direction. A regulator IC 7805 regulates the voltage to 5V at the output. The two capacitors used before and after the regulators eliminate the ripple voltage so a constant voltage can be produced.

Light dependent resistors have resistance in mega ohms when it is placed in dark producing logic high at the output and low resistance when placed in light i.e. logic low at the output. This output is received by op-amp which compares the two inputs and send output to  the two transistors. The first transistor inverts the input and the second transistor drives the buzzer. The buzzer starts ringing when the logic is high and also the LED starts blinking.

FM Transmitter

FM Transmitter:

Components Required:

  • 9V Battery
  • Resistors: 15k and 1K each.
  • Capacitors: 0.001 uF, 4.7 pF and 10-40 pF each.
  • Inductor Coil
  • Electret Mic for Input Audio
  • Transistor: 2N3904
  • Antenna 15"


FM transimission is done by the principle of audio pre amplification, modulation and then transmission. Here, we amplify the audio input signal taken from the Electret Microphone with the help of the transistor Q1, modulate it according to its frequency with the help of the inductor coil and finally we transmit it through the antenna connected to the inductor coil. This is just a simple model of FM transmitter and it works just up to a certain range (about 100-200 meters).

Note: We should keep in mind that modulating transmission of a certain standard frequency is a breach of the law and it should not be practiced in real life. So, just build it as a learning project in a very small scale.

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Line Following Robot With Manual Control

Line Following Robot With Manual Control: Line Following Robot Components Required: Arduino UNO A Chasis for your BOT ( Yo...