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Week Eleven : Input Devices


Assignment


In this week, we had to add a sensor to a microcontroller and read that value

We had a brief session on sensors from our instructors


I have decided to use a IR Sensor(Infra-Red Sensor)


An infrared sensor is an electronic instrument which is used to sense certain characteristics of its surroundings by either emitting and/or detecting infrared radiation. Infrared sensors are also capable of measuring the heat being emitted by an object and detecting motion


sensor

DESIGNING


I have used EAGLE for designing PCB

I have downloaded libraries from Atmel and Fab directories. From those libraries I have added the components needed for my PCB

I wanted to make a PCB which is used for the working of both Input and Output devices.So I have decided to modify the "FabKit v.0.3-0.4"

So I chose Microcontroller - Atmega328P-AU, so I can get many ports for both input and output devices


adding

Schematic Representation


I have used Atmega328P-AU, ISP pinheader, FTDI pinheader, Switch, Resonator, Resistor and a Capacitor


schematic

Switching to Board


I have connected the components using "NET" and switched it to board


switching

Manual Arrangement


Before Autorouting, I have manually arranged the components


arrrangement

Setting Design Rules


Before Autorouting, I have set the rules for Clearance and Sizes to 16 mill and 18 mill respectively


rules


rules

AutoRouting


Only half of the components got autorouted, so I have routed the other half manually using "ROUTE"


autoroute

Through Holes


2-3 components are given through holes to get a connection


input

DESIGN


I decided to give a different shape for the border


dimension

Settings on Milling Machine


Individual settings for Traces, Dimension and for Through-Holes


trace

dimension

I had to use gimp inorder to Invert the image and fill colors in the holes


designing

Through-Holes

Milled PCB BOARD


Traces didnt go well


board

Im planning to do another design for modification of Fabkit or a simple design for Input device

RE-ARRANGED CIRCUIT


I have re-arrranged all the components and changed the design rules of sizes to 13-mill


designrules

We have to individually export the "TOP layer with PADS & VIAS", "layer with PADS & VIAS" & "DIMENSION layer of the Board"


top

pads

dimension

We have to Export each files with "2000 resolution" and "Monochromatic"


saving

Pads need to be filled, as the exported files is having hollow pads.We have to fill it, so it mills completely


gimp

FINAL DESIGN


gimp

Settings on Milling Machine


Individual settings for Traces, Dimension and for Through-Holes


trace

dimension

throuh-holes

Milled ISP BOARD


isp

Components Used for my ISP Board


Microcontroller - Atmega328P-AU 
Capacitor - 10 uF 
Resistor - 10 Kilo-Ohm 
Resonator - 20 MHz SMD
FTDI - PinHeader
ISP - 2*3 PinHeader
GPIO - General Purpose Input-Output Pins
Switch

components

SOLDERING


soldering

ISP BOARD


gimp

Checking My ISP BOARD


sudo avrdude -c usbtiny -b 9600 -p m328p

gimp

Programming Using Arduino



   
     int obstaclePin = A0;
     int hasObstacle = LOW;


     void setup() {

     pinMode(obstaclePin, INPUT);
     Serial.begin(9600);
     }
     void loop(){
      hasObstacle = digitalRead(obstaclePin);

     if (hasObstacle == HIGH)
     {
       Serial.println("Path is clear");
      delay(1000);
     }
     else
     {
       Serial.println("Stop, Something Ahead!!");
       delay(1000);
     }
     delay(100);
     }



Setting Board, Processor, Clock, Port, Programmer and Ports



prgram

prgram

Programming Using Arduino


prgram

HEROSHOT


Heroshot

Video












Group Assignment


The sensor is a module or a chip that observes the changes happening in the physical world and sends the feedback to the microcontroller. Microcontroller accepts two types of input - Digital and Analog

Analog sensors sense the external parameters and given output in a range of 0 to 5V. For example, if we are using LDR sensor module. In 9.00am it gives an output of 3v and 11.00am output is 4v and 1.00pm output is 4.5v and in night output is 1v. It shows that analog sensors measure the quantity not only the presence of something


prgram

Digital Sensor produce discrete values (0 and 1). Discrete values often called digital (binary) signals in digital communication. For example, if we are using PIR sensor, It gives output of 3.3v when motion is detected and 0v were no motion detected. Here we used Arduino connected with PIR sensor and run the code and made the plot


prgram