Author Archives: Logeswari S

Shell commands

I learnt about shell commands. A Shell is an environment which is used to run our commands and programs. It is an user interface with the operating system. There are many different types of shell. I learnt some commands in bash and C shell. Bash is one of the original shell which developed for UNIX computers. C shell was developed based on model of C programming syntax. To know which shell you are using type echo $0.
I learnt how to define variables both in bash and C shell. Bash is denoted by $. The syntax to define a variable is $a = 5
To print the value of the variable use the command echo $a. In C shell we need to set the environment variable. So the syntax goes like this. setenv a 10. An environmental variable has the name and the value.
To go to the home directory ~/.cshrc and ~/.bashrc for C shell and Bash respectively.

Cutting Bamboo

In Saturday school students had different tasks to do in school. One of them was cutting bamboo tree and making them into pieces for putting banner in many places in Auroville. The banner was for Isai ambalam School. The day before (Friday) students had already cut some of the bamboo tree. We knew the specifications of how many bamboo sticks are needed and what are all the measurements. We need to 12 sticks of 17 feet (5 meters and 10 cm) and 12 sticks of 11 feet (3 meters and 35 cm). Students measured the length using tape and cut them using axe ,saw and knifes. While doing this task the students measurements and conversion of feet to meters.

India map

Students from 6th and 7th graders made India map using red soil, clay, bricks, pebbles, sand, alluvial soil, black soil. They first wanted to make it on the loft. First they drew a three meters height and three meters width box. Each student were given separate parts of the country to draw. By using graph sheets they drew the map of India.

They made the structure of India using clay. Since there was heavy sun on the loft, the clay got cracks. So students decided to make in on the ground. They did the same thing in the ground. Now they gave shelter to it. But still after a few days it had cracks. Then students came up with a solution that since the layer of the clay is so thin, it had cracks. We had some remaining soil left after the work of oven Education By Design (EBD), so students used that red soil and created another layer above the clay. By using bricks and red soil students built the mountains. In order to differentiate between desert, mountains and rivers they used different materials. For the rivers they mixed the cement with water and built many rivers in India. For desert, they put normal sand. In the eastern parts of the country, they put the alluvial soil. Because the rivers take the alluvial soil and leave it in the delta before joining the sea. Tasks were properly divided among students and it took about two weeks for them to complete the map. The final output of the map was looking good with mountains, rivers and other geographical features. By doing this EBD they learnt Geography of India. Their teacher Ragu supported them.



First digit on clock

– Logeshwari

In electronics, initially I displayed my name using Seven Segment Display(SSD). I had already posted that in My First Blog. After that I wanted to learn more on SSD. So I was asked to make a digital clock. I have completed the first digit of the seconds. I used two JK flip flops (HD74LS76A), decoder (SN74LS47), a SSD (Common Anode) and Signal Generator. I first made the connections of JK flip flop on a breadboard. The input is clock signal which is generated from a signal generator of Frequency 1Hz. The combination of the two flip flops acts like a counter. Once the circuit is connected, I tested the output of the flip flop using an ocilloscope. I got the waveforms like this.

Then I took the decoder and connected the outputs to the input pins of the decoder. Decoder (converts the binary information to 2n outputs) is connected to the seven segment display. While doing decoder I was able to recall Karnaugh-Map which is the logic behind it. The output of the decoder is fed to the seven segment display. Once everything is done then it counts from zero to fifteen (f-represented in binary).


Since the one’s digit of the clock counts only upto nine and after that it should reset to zero. For resettting the digit to zero I used NAND gate. Binary representation of nine is 1001. When the Most Significant Bit and the Least Significant Bit are high(1) then it should reset to zero.


I have completed the first step only, but I feel happy that I learnt and understood what I did. I acknowledge Sanjeev, Sundhar and Ranjith for guiding me.

Projects for Raman awards – Isaiambalam

Raman Young Science Innovator Award is a contest for students studying from III to X standards grouped into three. Students from IIIto IV, V to VIII and IX to X. We heard about this contest and started registering for it on 31st January. The registered students got their login credentials through their mail after 31st January. We submitted their projects on the last date on 10th February (extended to 12th February). Eight students submitted their innovation projects from Isai ambalam School. They are Ayush Jena, Suresh and Vasanth Kumar from class VII. Balamurugan, Kaviya, Sabari anandh and Yuvasri from class VI and Sharani from class V.

Ayush Jena (Class VII)
Ayush chose the topic buoyancy. He made an animation using scratch which explains the buoyancy of ships.

Suresh (Class VII)
He made his project on conductors and non-conductors.His main objective of the project is to find if the material is a conductor or non-conductor.He made a circuit and placed in inside a box.If the material is a conductor then the light will glow. If the light doesn’t glow then the material is not a conductor(non-conductor).The materials he used to make this project are wires, bulb, battery, box and iron.

Vasanth Kumar (Class IX)
Vasanth Kumar chose the topic Plant Kingdom. He took banana and he made an animation using scratch.In his animation he explained the benefits of bananas, scientific names and different things about it.

Balamurugan (Class VI)
He chose the topic density. He took a bowl of water and filled water upto 100 ml. Then he put some stones in the bowl until the water level rises to 110 ml. Then he took the stones in the bowl and weighed them with a weighing machine. It was 100 gm, which is equal to the rise in the water level.

Kaviya (Class VI)
Kaviya made her project in convection. She experimented by using coloured ice cubes. She was able to see the colour of the ice cubes get sink in the water. She observed that the speed of the speed of the ice cubes dissolving in water.

Sabari Anandh (Class VI)
Sabari chose the topic Plant Kingdom.He made his project using scratch. He selected neem, squirel, mamgo and described their important characteristics. Then he explained what is the connection between them using scratch.

Yuvasri (Class VI)
Yuvasri chose the topic melting point. She tested the melting point of ice cubes. She understood why the ice cubes melts when heated and what happens when heated.

Sharani (Class V)
Sharani chose the topic density. She took honey, vegetable oil, soup oil, coloured water and syrup. She poured all the liquid one by one glass bottle. Honey settles down because it has density greater than one. Similarly she formed five layers in the bottle.

Raman Award Projects – Udavi School

Raman Young Science Innovator Award is a contest for students studying from III to X standards grouped into three. Students from III to IV, V to VIII and IX to X. We heard about this contest and started registering for it on 31st January. The registered students got their login credentials through their mail after 31st January. We submitted their projects on the last date on 10th February (extended to 12th February). 11 students from Udavi School chose their topics and submitted their Innovation projects. They are Abitha, Amsavalli, Hariharan, Kabilan, Punidhavel, Suriya and Vignesh from IX standard. Baranidharan from VIII and Arvindh, Pranav and Vishal from VII standard. The topics were based on their standards.

Abitha (Class IX)

Abitha chose the topic refraction. She studied about refraction in her academic books, so she thought of making it in practical. She made her project using GeoGebra. GeoGebra is a Dynamic Mathematics Software (DMS) for teaching and learning mathematics. She used two mediums. Both of them are air. The incident ray and the refracted ray has the same angle. The refraction index of the second medium increases then the angle decreases.


2.Amsavalli (class IX)

Amsavalli did a project on reflection. She did her project using GeoGebra.When the incident ray falls on the mirror and the ray gets reflected. This is the reflected ray. She showed the angles of the reflection in an animated form.

3.Hariharan (Class IX)

Hariharan chose the topic frequency. He made his project using Arduino. He used an ultrasonic sensor which will detect the object. He wrote his program in Arduino. When any object is placed in front of the ultra sonic sensor it makes beep sound. When the object is far from the sensor the volume becomes low. Based upon the distance of the object to the sensor, the sound will differ.

4.Kabilan (Class IX)

Kabilan made a microscope using a mobile phone and lens of laser light. He placed the object on the lense and it shows the enlarged image of it in the mobile. He made this microscope, because when he was using a microscope the light hurt him. So he wanted to make a microscope which does’t hurt. He tested the microscope by seeing the microscopic view of leaves and insects.

5.Punidhavel (Class IX)

Punidhavel made a piano using resistors, basar and battery. He made his connections in a breadboard. He used resistors and buzzors to make sound. After completing the project he made the sa re ga ma tune.

6.Suriya (Class IX)

Suriya made a pie chart using GeoGebra about the natural gases in the atmosphere.

7.Vignesh (CLass IX)

Vignesh chose the topic frequency. The materials which Vignesh used are ocilloscope, microphone and  341 tuning fork. He measured the frequency of tuning fork with the help of microphone and oscilloscope. By using this we can also measure the heart beat frequency.

8.Bharanidharan (Class VIII)

He made an inverter using Arduino. The materials he used are Arduino, Breadboard, voltage regulator, resistor(10 k ohm), 9V battery, transformer, wires and laptop. He made a program to blink the Led at 50Hz. Then he dumped the program in the Arduino. He connected it to a CRO and saw the square waveform. Then he connected the remaining circuits on the breadboard. He used the voltage source from which nine volt DC input is fed to the transformer. The output of the transformer is 230 volt AC. After that he connected a 5 Watts bulb to the ouput. Eventually the bulb glowed.

9.Arvindh (Class VII)

He made his project on slow combution explaining the ignition temperature.

10.Pranav (Class VII)

Pranav made a steam engine.He took two wooden pieces and on each edge he made a hole and put a screw. He placed a tin above the wooden pieces and stuck it with glue. He made a hole on top and one side of the tin. He broke the pen into two and inserted each piece in the two holes. Then he kept a motor which was connected to another wooden piece. A Led was also connected to this wooden piece. When fire is lit up, it goes through the tin and it makes the turbine to rotate.

11.Vishal (Class VII)

Vishal made a project on combution. He made a small stove using two tins. First he took the small tin and made holes then the bigger tin and made holes in it. The smaller tin is placed inside the bigger tin. A vessel is placed on the tin. Using small wooden pieces he made fire. He poured water in the vessel, which got heated quickly.

Students made their project with their full involvement and felt happy after submitting their innovation project.

Second workshop on Stewardship for new Emergence

On Monday, 29th January we had the second session of the workshop – stewardsip for new emergence. In this workshop we discussed about four profiles namely wisdom, social personality, and professional From the four profiles the one that I could connect the most was my professional profile. I am now working on a digital clock, I haven’t completed it yet but the insight of being a professional reminded me to try and complete the work that I am doing. Initially I had no idea of where to start and what to do. Now I have learnt about the counters and decoders which is used in the digital clock that I am creating. I was also able to recall the Karnaugh Map which I had studied in my college days.

My first Blog

This is my first blog and I am going to share what I learnt in STEMLand. I learnt the basic connections in a breadboard and about seven segment display. There are two types of seven segment displays, they are Common Anode(CA) and Common Cathode(CC). I figured out the differences I was able to display my name with the use of wires, resistors, battery and breadboard. It was a new experience for me and I learnt a lot..

After displaying the name, I learnt how to turn on off a LED bulb by building an oscillator. Then  connected both the circuits and made my name blink. I was able to find the voltage across a resistor by using a multimeter.


In the Learning Festival held at Indira Gandhi Government Higher Secondary School in Pondicherry, I learnt more about the SSD’s. We We held a session for the students and the goal was to write their names on the SSD’s. It was a good and happy experience working with students. I visited other sessions where different people from various background had come They made handmade soap, art using coconut shell, naturally made tooth powder, clay works and many more.

I learnt how to interact with students in many different ways, for solving problems in maths, I also got the opportunity to interact with Swati: she introduced us the chocolate plate method for solving questions in division which was new and interesting to solve.