View source for Shriya Rathi

== Prelude ==
=== About me ===
Hi, I am Shriya, currently learning Industrial Design from Srishti Institute of Art, Design and Technology. I aspire to be a Product Designer and so I feel it is important to have learnt some basic information about electronics and technology. This thought of coming out from the comfort zone and learning science pulled me towards this course. Coming from a commerce background, I did not have good knowledge of physics. I knew I was entering the class with a blank mind hoping to learn how things work in the world of technology.

=== Introduction to basics ===
As the day started, we got introduced to the arduino software (works with C++ language) which can communicate with the arduino electronic plate and can interact with the things attached to it. To my understanding, the digital side is for the output and analog side is for the input. 

==== Sensors ====
I looked closely to the basic things that can be attached to arduino, processed and had an outcome. We, in groups, touched our hands on LED (light emitting device), jumper wires, buzzer,LDR (Light Dependent Resistor), bread board and played around by putting one leg on ground, one on the digital side, changing the values and getting different results. Learnt the functions of a bread board which is used for prototyping connections, potentio meter with three legs and soldering the connections. Sitting in a helped us share each other’s knowledge and mistakes.

==== Series Connection ====
The current in a series circuit goes through every component in the circuit. Therefore, all of the components in a series connection carry the same current. There is only one path in a series circuit in which the current can flow. The total resistance of resistors in series is equal to the sum of their individual resistances. If we have to increase the resistance in a circuit, use series connection. For example, in a fairy light, the connection is a series connection. If one LED out of the many in the row looses its connection, all the other lights stops working.

==== Parallel Connection ====
The current in each connected  branch line is different. The total current is the sum of the currents through the individual components. In parallel connection, the heads of the resistors are connected together and the tails are connected together. This decreases the total resistance of the circuit. For example, if 3 bulbs are connected together in a parallel connection and stops working due to loose connection, the other two bulbs will still work as the current flowing in each branch line is different.

==== Capacitors ====
A capacitor is a device use to store electric charge like a small rechargeable battery. The effect of a capacitor is known as capacitance. 

== Field visit ==
=== Puttenahalli Lake, Yelahanka ===
==== Purpose of Visit ====
First visit to Puttenahalli Lake was scheduled on 7th march to collect lake water and rain water. A kit was prepared of the things we will need for the collection of water and documentation like closed containers, tissues, brush, labels, clean water, dropper, threads etc. We collected 8 different samples of water from different layers using ladle, threads, stone for weight so that the container touch the deeper layers of lake water and manually pouring it. The purpose of collecting lake water was to study its components and find diatoms in it.

==== Reflection ====
We had to do quite a few attempts to get the desired water. While gathering the water and soil samples, we realized we have forgotten some useful things in the kit. I noticed a pre-planing to the trip was required which we had done in class as to what kind of sample we want, sample from the shade, sample where water meets sunlight, rain water sample and different layers of water sample. It was a nice environment with birds and dogs accompanying and a good learning on how to collect samples for lab tests. 

== Projects ==
=== Touch me not monster ===
==== Brief ====
Touch me not monster is child's play which crawls when touched at a particular point repeatedly.
This piece was built using 
#arduino uno
#2 servo motors 
#IR sensor

The two servo motors are attached together in a way that both the rotating fan are opposite each other connecting it to and arduino uno and an IR sensor.

==== Reflection ====
Being at a learner’s stage, I was trying to understand how 2 or more than 2 sensors and motors are connected together with respect to its coding. Learnt how to solder and worked on covering the wire structure. To hide the technical part, we connected the monster’s legs to the rotating fan of the servo motor and made the body using some colourful thick threads.

=== ECG Meter ===
==== Instructions on how to use an ECG sensor ====
ECG Meter is a device used to monitor the continuous heart activity of a patient in relative to their cardiac rhythm. 
'''Hardware required'''
#Arduino Mega
#ECG sensor board
#ECG Electrodes - 3 pieces
#ECG Electrode Connector -3.5 mm
#Power supply
#Connecting Wires

'''Connection of ECG sensor with Arduino'''-
The ECG sensor comes with 9 pins. 6 pins for input connections and 5 pins to connect Electrodes. The input connections are as follows-
   
   Board Label	Pin Function         Arduino Connection 
   GND	        Ground	             GND
   3.3v	        3.3v Power Supply    3.3v
   OUTPUT	Output Signal	     A0
   LO-	        Leads-off Detect -   11
   LO+	        Leads-off Detect +   10
   SDN	        Shutdown	     Not used
   
We already have an external cable connecting all the three parts of electrodes so we directly plug it in.  

'''Coding'''-
Select the arduino mega board, follow the coding and upload. Change the values according to the requirement.
image

[[File:ECG Arduino Coding.jpeg|700px]]

Attach the 3 Electrodes to the body. Click on serial monitor to get the readings.

==== Reflection ====
To join the circuit of an ECG sensor was easier than I thought. We looked up online for the reference of the connection and the code. In no time we could figure the circuit and it was working. We user tested the electrodes on the hand wrist to get the readings. The part we got stuck was to understand the reading of the ECG meter. The online manual said we needed to download different processing software to see the heart rate graphs.

=== Turbidity Meter ===
==== What is Turbidity Meter and how to build it ====
Turbidity is the cloudiness or haziness of a fluid caused by large numbers of individual particles that are generally invisible to the naked eye. Turbidity meter is used to measure the water clarity, the amount of suspended sediment in water which blocks light.

'''Hardware Required'''
#Arduino Uno
#Light source- LED (Light Emiting Diode)
#LDR sensor(Light Dependent Resistor)
#Resistor
#Connecting wire
#Switch button

'''Connecting LED'''- Bigger leg to 13 and smaller one to the ground.

'''Connecting LDR'''- Make a third leg of the LDR using a resistor. Connect the first leg to the power of 5v, centre to A0 and last to the ground. 

The meter works when LED and LDR face exactly each other with a gap in between for the sample to be placed. It gives the reading on the basis of the amount of light that travels between the water sample and reaches to LDR. More the light, more clear the water and vice versa. Attach a switch to the LED for the device to turn on and off. 

'''Coding'''

[[File:Code.PNG|700px]]

'''Sample'''

6 samples were used to test the turbidity meter.
 
sample 1- 100% milk

sample 2- 10% of sample 1 and 90% water

sample 3- 10% of sample 2 and 90% water

sample 4- 10% of sample 3 and 90% water

sample 5- 10% of sample 4 and 90% water

sample 6- 100% water

[[File:Sample1.jpg|150px]] [[File:Sample2.jpg|150px]] [[File:Sample3.jpg|150px]] [[File:Sample4.jpg|150px]] [[File:Sample5.jpg|150px]] [[File:Sample6.jpg|150px]]

'''Graph'''
Graph from the readings of 6 samples

[[File:ChartGo.png]]

==== Reflection ====
Initially, the reading range was in between 0 to 8 which did not make a major difference in two samples. Then, we altered the connections of the LDR and we could see the readings in hundreds. Another decision we had to make was to which color LED to use. we chose to use red because it travels in a straight path with less deviation. Soldering was a bit difficult and fun as it was my first attempt to make a complete soldered circuit. To cover the connections, we used a neat and nice looking cosmetic box, made holes for the test tube samples to go in and switch to come out. Due to these holes, there wasn't 100% darkness inside the box so I had to cut the holes with precision again. But later after measuring the samples, I understood that difference between the reading without the sample and with the sample gives the accurate measure. Overall, I started the understanding of sensors from scratch and now I have a little bit of confidence in me that i can work with it and understand what is going wrong and where.