Evolocity Innovation Build

# Innovation Challenge: Building a Dashboard for Your EV
### EVOLOCITY 2021

.TitleAuthor[Duleepa J Thrimawithana]

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.logo-slide[]
.footer[[Duleepa J Thrimawithana](https://www.linkedin.com/in/duleepajt), Department of Electrical, Computer and Software Engineering (2021)]

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name: SI1

# The University of Auckland

- Highest ranked New Zealand university and 85th in the QS World University Ranking
- Over 5,000 staff members and 40,000 students
- Nine faculties including Medical & Health Sciences, Engineering, Business & Economics and Science

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name: SI2

# Dept. of Electrical, Computer & Software Eng.

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name: SI3

# Dept. of Electrical, Computer & Software Eng.

.left-column[
- One of the 5 departments in the Faculty of Engineering
- Offers 3 undergraduate degree programs
 - Electrical & Electronics, Computer Systems and Software
 - Project based teaching
- 35+ full-time academic staff members and 15+ post-doctoral research fellows
- 150+ postgraduate students and 600+ undergraduate students
- Regular visiting research scholars and research students
- Research groups include Power Electronics, Power Systems, Signal Processing, Robotics, Embedded Systems, Parallel Computing, Telecommunications and Control Systems
]

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name: SI4

# Pioneers in Wireless Power Transfer (WPT)

.center[
<iframe width="784" height="441" src="https://www.youtube-nocookie.com/embed/G1q1HZLQ528?" frameborder="0" allow="accelerometer; autoplay; encrypted-media; gyroscope; picture-in-picture" allowfullscreen></iframe>
]
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# Introduction to Innovation Challenge
### What Should We Build?

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.logo-slide[]
.footer[[Duleepa J Thrimawithana](https://www.linkedin.com/in/duleepajt), Department of Electrical, Computer and Software Engineering (2021)]

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name: S1

# A Dashboard for Your EV

- Provides performance feedback to the driver as well as the design team 
  - Battery status and drive power 
  - Speed, distance and acceleration
  - Temperature, indicators, etc.

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name: S2

# What Can We Measure?

.left-column[
- Battery temperature, voltage and current can be measured 
 - Allow estimating the remaining capacity of the battery, drive power and if battery is operating safely
 - Can use temperature, voltage and current sensors
- Wheel speed and acceleration can be measured 
 - Allow estimating the speed and acceleration of the vehicle
 - Can use a tachometer or feedback from motor
- User inputs can be measured
 - For example pushing brake pedal, turning-on indicators, etc.
- Location of the car can be evaluated
 - Allow navigation, obstacle detection, speed estimation, etc.
 - Can use GPS, LIDAR, cameras, etc.
]

.right-column[
.center[
.zoom175[
<img src="img/VISens.png" class="noborder" alt="V & I Sensor" width="200px"/>
]
.zoom175[
<img src="img/MagneticSpeed.png" class="noborder" alt="V & I Sensor" width="200px"/>
]
.zoom175[
<img src="img/BrakePedal.gif" class="noborder" alt="V & I Sensor" width="200px"/>
]
]
]

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name: S3

# How to Convert Measured Signals to Useful Data?

- A small computer can be used to collect the data from all our sensors and convert them to useful information
 - For example, the computer can read the outputs from the voltage and current sensors and calculate important information like the remaining battery capacity or the drive power
- The output from most sensors are in analog form but the computer can only understand digital numbers
 - Luckily, most micro computers can convert the output from sensors to digital numbers (i.e. 1s and 0s) and process these numbers to obtain useful information
- A circuit is provided to you that has a voltage sensor, current sensor, LCD display and an Arduino Nano micro computer
 - We named this the "EvoSens Board" and the information coming from the sensors on this board is used by the Arduino Nano computer to work out important information about your vehicle 
- The "EvoSens Board" also has the ability to send information wirelessly using Bluetooth 
 - You can also connect other sensors like a tachometer or a brake sensor to the "EvoSens Board" using expansion pins provided

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name: S4
 
# The EvoSens Board

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name: S5

# How Can We Display Measured Signals?

.left-column[
- A [HD44780 type LCD panel](https://www.arduino.cc/en/Tutorial/LiquidCrystalDisplay) can be used to display information to the driver 
- LEDs can be used for indicators
 - For example, brake lights, warning indicators, turning indicators, etc.
- A mobile phone/tablet connected using Bluetooth can also be used as a 'fancy' dashboard
 - Involves developing a mobile app using a tool such as [AppInventor](http://appinventor.mit.edu/explore/)
- An IoT platform can be used to log data and view this data remotely
 - [ThingSpeak](https://thingspeak.com) provides a free service
 - Data can be used to improve the performance of your vehicle
]

.right-column[
.center[
<img src="img/EvoMeter.png" style="border:1px solid black" alt="EvoMeter" width="220px"/>
]
]

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name: S6

# System We Plan to Build

<br>

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name: S7

# System Diagram of the Build

- When engineering a complex system, we divide it into more manageable smaller problems
  - Each smaller problem to solve is shown as a block/box
  - Connected boxes show the complete system we plan to build

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# Building an Electronic Circuit
### Learning to Use a Breadboard

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.logo-slide[]
.footer[[Duleepa J Thrimawithana](https://www.linkedin.com/in/duleepajt), Department of Electrical, Computer and Software Engineering (2021)]

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name: S8

# How Can We Build a Circuit Quickly?

.left-column[
- We need a way to connect electronic components together to build a circuit
 - This is typically done by soldering the components on to a printed circuit board (PCB) 
- If you had to build a simple circuit quickly how will you do this?
 - Getting a PCB made takes time 
- A breadboard can be used to help build a circuit quickly
 - Component legs are inserted into holes in order to make connections with other components
 - Holes are electrically connected with other holes as indicated in the diagram
- Alternatively you can use a Veroboard
]

.right-column[
.center[
.zoom175[
<img src="img/PCB.png" class="noborder" alt="PCB" width="200px"/>
]
.zoom175[
<img src="img/soldering.gif" class="noborder" alt="Soldering" width="200px"/>
]
.zoom175[
<img src="img/Breadboard.png" class="noborder" alt="Breadboard" width="200px"/>
]
]
]

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name: S9

# Building an LED Circuit with On/Off Switch

- Lets assume we want to build a circuit that lets us turn-on and turn-off an LED with a switch
 - When the switch is closed by pressing the knob, 5 V from the battery is applied lighting the LED
- A push-button, an LED and a resistor can be assembled on a breadboard to create this circuit
 - The resistor limits the current through the LED and therefore controls its brightness 
- Lets assemble these components on a breadboard as in the picture and power it using a 9V battery
 - We can also use a circuit diagram to show how components should be connected (on the right)
- How can we make the LED brighter? Is this how a light switch at home works?

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name: S10

# Building a Voltage Sensor Circuit

.left-column[
- Battery voltage is too high to measured by an Arduino computer
 - The voltage sensor steps-down the battery voltage to a value that can be measured by the Arduino computer
- A voltage sensor can be made using two resistors that form a voltage divider
 - Voltage at the mid point of the divider (sensor) is 
\\[\text {Measurement} = \text {Battery Voltage} \times \frac {R\_{VSENS2}} {R\_{VSENS1} + R\_{VSENS2}} \\]
- Lets build a voltage sensor to measure the voltage of a 9V battery
 - Use `$ 10k\Omega $` and `$ 130k\Omega $` resistors to step-down the voltage
 - With a multimeter confirm you get 0.64V at mid point
 - Lets now try using 24V instead of the 9V battery
]

.right-column[
.center[
<img src="img/VoltageDiv2.png" class="noborder" alt="Voltage Divide" width="300px"/>
]
]

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# Programing Fundamentals
### Learning to Use Arduino IDE

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.logo-slide[]
.footer[[Duleepa J Thrimawithana](https://www.linkedin.com/in/duleepajt), Department of Electrical, Computer and Software Engineering (2021)]

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name: S11

# What is a Computer?

.right-column2[
- A computer is an electronic device that can *receive, process, and store data*
- A computer has a processor which can manipulate the data by adding, dividing, subtracting, etc.
- The inputs are recieved from for example, keyboard, mice, mic, etc.
- The data is stored in memory 
]

.left-column2[
.center[
<img src="img/computer_internals.PNG" class="noborder" alt="Diagram of the parts of a computer" width="550px"/>
]
]

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name: S12

# Computers

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# Which Computer Should We Use?

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- A microcontroller is the most suitable computer for your system
 - An _embedded_ computer
 - Low power consumption
 - Sufficient processing power
 - Useful in-built peripherals including an analog to digital conversion (ADC) circuit
 - Cheap and easy to use
- An Arduino Nano is suitable for our project
 - It is a microcontroller (micro-computer)
]

.left-column2[
.center[
<img src="img/MircroArch.png" class="noborder" alt="Micorcontroller" width="600px"/>
]
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name: S14

# How to Make Our Microcontroller Think?

- Use *variables* and *conditionals* to implement *algorithms*
 - A variable is used to store data and has a type like *int* and *char* 
 - Conditionals are used to make decisions using statements like *if* and *else* together with logical operators that are used to compare variables
- Loops are used to repeat a set of instructions
 - *for* and *while* loops are commonly used
- Instructions are written in a low level programming language such as C
 - Program is organized into *functions* for our sanity
 - Use comments to explain what each part of the program does
 - Compilers convert the program to machine code that the microcontroller can understand
- Machine code is loaded to the microcontroller
 - We call this "programming the microcontroller"
 - Using programming hardware

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name: S15

# Arduino Nano and Arduino IDE

.left-column[
- Arduino Nano is the recommended micro-computer for this project
- Arduino Integrated Development Environment (IDE) provides a simplified interface to write your software program 
 - An Arduino program is called a *sketch*
- There are many useful Arduino libraries to simplify programing
 - Easy use of peripherals and shields
 - Many examples and abundant support forums
 - Your software can be written in a C language
- The Arduino Nano micro-computer board we will use has
 - An 8-bit microcontroller (ATMega328P) made by Atmel
 - Many digital and analogue pins + a USB programmer
 - Cheap (~$12)
]

<img src="img/Nano.jpg" style="border:none" alt="Nano Pin Map" width="350px"/>
]
]

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name: S16

# Using Arduino IDE to Program Arduino Nano

.right-column3[
- Connect the Arduino Nano board to the PC using USB cable
- Tell Arduino about the board you use
 - Go to Tools > Board and select "Arduino Nano"
 - Go to Tools > Processor and select "ATMega328P (Old Bootloader)"
 - Go to Tools > Port and select the correct one
- You can use an example program provided in Arduino IDE for testing 
 - Lets open the *Blink* example, from File > Examples > Basics > Blink
 - Compile, and upload (program) to verify it works
]
.left-column3[
.center[
<img src="img/BlinkingLEDEg.png" style="border:none" alt="Blinking Example" height="420px"/>
]
]

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# Learning to Programing
### Writing Simple Programs for an Ardunio

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.logo-slide[]
.footer[[Duleepa J Thrimawithana](https://www.linkedin.com/in/duleepajt), Department of Electrical, Computer and Software Engineering (2021)]

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name: S17

# Turning an LED On and Off with Arduino (P-I)

.left-column[
- We learnt to use a push-button to turn a LED on and off
 - Pushing the button supplied battery voltage through a resistor to an LED turning it on
 - Releasing the button removed the voltage turning the LED off
- Can we use an Arduino microcontroller to automate this process?
 - When a digital pin is set to produce a logic high output it behaves like a turned-on switch and supplies 5V
 - When a digital pin is set to produce a logic low output it behaves like turned-off switch and supplies 0V
- Thus a digital pin can replace the push-button
 - Modify your LED circuit by connecting pin 6 of the Arduino to where the positive (red) wire of the battery was and ground of the Arduino to where the negative (black) wire of battery was 
]

.right-column[
.center[
<img src="img/ledblink.gif" class="noborder" alt="LED Blink Animation" width="220px"/>
<img src="img/LEDBlinkW.png" class="noborder" alt="LED Wiring" width="220px"/>
]
]

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name: S18

# Turning an LED On and Off with Arduino (P-II)

.left-column2[
- Click on File > New to create a new program  
- In your program first 'setup' pin 6 as an output pin 
 - Pin 6 can now produce 5V (logic high) or 0V (logic low) similar to switch turning on or off
- We could also 'setup' a digital pin to read digital inputs
 - We will look at an example later
- To blink LED, flip the digital pin between 5V and 0V every 1s
- 5V is produced by writing a logic high to the digital pin
 - Keep 5V on for 1s by 'delaying' 1s
- 0V is produced by writing a logic low to the digital pin
 - Keep 0V on for 1s by 'delaying' 1s
- Tell program to 'loop' indefinitely through this program
 - Test this in your circuit
]

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.center[
<img src="img/BlinkingExample.png" class="noborder" alt="LED Program" width="400px"/>
]
]

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name: S19

# Communicating with a PC (P-I)

.left-column[
- Microcontrollers communicate with other devices through many methods
 - Examples include USB, HDMI, Serial, CAN, etc.
- *Serial* provides a simple way to send/receive messages
 - Send/receive a stream of logic-highs and lows over a wire 
- Most devices, communicates with the microcontroller using serial
 - Examples include PC/laptop, Bluetooth modules, screens, etc.
- Lets get the Arduino Nano to display your name on the PC screen
 - In your program, first 'setup' *Serial* communication at a speed of 9600 bps
 - In the loop, using *Print* function send your name to the PC every second
- Use Arduino *Serial Monitor* to view message on the PC
]

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.center[
<img src="img/Serial.png" class="noborder" alt="Serial Diagram" width="220px"/>
]
]

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name: S20

# Communicating with a PC (P-II)

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# Starting Work on the Dashboard 
### Measuring Battery Voltage & Current

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.logo-slide[]
.footer[[Duleepa J Thrimawithana](https://www.linkedin.com/in/duleepajt), Department of Electrical, Computer and Software Engineering (2021)]

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name: S22

# Digital and Analog Signals

.left-column[
- Binary signals that correspond to a logic high (true) or logic low (false) are called digital signals
 - A logic high is (usually) 5V and a logic low is 0V
 - Digital signals are read or produced using a digital pin on a microcontroller
 - Need to setup the pin as an 'input' or an 'output' pin
- Continuous signals that change over time are called analog signals
 - A microcontroller reads the analogue voltage signals using specific analog pins, which are connected to an Analogue to Digital Converter (ADC)
- An ADC convert an analog voltage to a digital (integer) number
 - Arduino Nano has a built in ADC
 - Higher ADC resolution improves accuracy
]

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name: S23

# How Does an ADC Work?

.left-column[
- The analogue pins A0 to A7 of the Arduino Nano are connected to Arduino Nano's Analogue to Digital converter (ADC) unit
 - For example, the analogue voltage at pin A0 can be read by the Arduino using the command analogRead(A0)
 - The value this command gives you is an integer number since computers love integers  
 - We need to use mathematics to find out actual voltage
- ADC on the Arduino Nano converts a voltage between 0V & 5V to an integer between 0 & 1023
 - For example, 2.5V applied to A0 will be read by Arduino as 512
- How can we use mathematics to work out the actual voltage?
 - What we get from analogRead(A0) need to divided by 1023 and multiplied by 5
]

.right-column[
.center[
<img src="img/ADCExample.png" class="noborder" alt="ADC Working" width="300px"/>
]
]

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name: S24

# Variables and Logic Statements

.left-column2[
- Variables act as memory to store values, similar to math
- There are different variable types 
 - Integer, character, float, string, unsigned int, etc.
- Crucial to define the correct type of variable
 - Variables 'A' and 'B' that hold an integer number can be defined as *int A* and *int B*
 - 'A' can be assigned a value as `$ \text {A=2*B or A=10} $`
- *if* and *else* statements can be used to make decisions
- Logic operators compare variables
 - Equal (A==B), not equal (A!=B)
 - Greater than `$ \text {(A > B)} $`, Less than  `$ \text {(A < B)} $`
 - AND (A&&B), OR (A||B)
]

.right-column2[
.center[
<img src="img/LogicExample.png" class="noborder" alt="Logic Example" width="450px"/>
]
]

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name: S25

# Measuring the Battery Voltage (P-I)

- Lets use the "EvoSens Board" to measure the voltage of you vehicle battery
 - In your real design this will be the 24V or the 48V vehicle battery
- For now connect the 9V battery across the terminals labelled "Battery" (make sure the polarity is correct)
- The voltage sensor on the "EvoSens Board" steps-down the battery voltage by 10/140
 - This is because `$ R_{sens1} = 130k\Omega $` and `$ R_{sens2} = 10k\Omega $`
- In your program, first 'setup' *Serial* communication at 9600 bps so we can display battery voltage on PC
- Output of the voltage sensor is connected to A0 pin
 - Read the voltage at A0 using *analogRead(A0)*
- *AnalogRead* converts a 0V to 5V signal at A0 to a number between 0 and 1023
 - To get the actual voltage we have to multiply the result by 5 and divide by 1023
 - We also have to multiply this number by 14 to get the actual battery voltage by reversing the step-down introduced by the voltage sensor
- Read and display the battery voltage on PC every 1s

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name: S26

# Measuring the Battery Voltage (P-II)

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name: S26

# Measuring the Battery Current (P-I)

.left-column[
- Battery current needs to be converted to a voltage to be measured by an Arduino 
 - A current sensor integrated circuit (IC) can be used for this
-	In "EvoSens Board", we use an IC called “ACS730” to measures the current flowing from the battery to the motor controller 
 - The output of the ACS730 IC is connected to pin A1
- The output of ACS730 is a voltage proportional to current through
\\[\text {Measurement} = \text {Battery Current} \times 0.04 + 2.5V \\]	
- For example, if the current flowing from battery is 20A then the voltage produced by the ACS730 will be 3.3V (i.e. 2.5 + 0.04 x 20)
- Lets improve our program to measure both the battery current and voltage and display on PC screen

]

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name: S30

# Measuring the Battery Current (P-II)

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# Using the Liquid Crystal Display (LCD)  
### Displaying Messages

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.logo-slide[]
.footer[[Duleepa J Thrimawithana](https://www.linkedin.com/in/duleepajt), Department of Electrical, Computer and Software Engineering (2021)]

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# Liquid Crystal Display (LCD) (P-I)

-	There are many display types we can use to show information about the vehicle
 - A monochrome LCD display is the most common and simple to use
 - We can use more advanced color displays as well (check an example [here](https://create.arduino.cc/projecthub/electropeak/ultimate-beginner-s-guide-to-run-tft-lcd-displays-by-arduino-081006))
-	EvoSens board is designed to accept an HD44780 compatible LCD display 
 - There are many sizes but we are using one with 2 lines, where each line can display 16 characters
-	We are going to use the [LiquidCrystal](https://www.arduino.cc/en/Reference/LiquidCrystal) library provided by Arduino to make things simple
 - You can visit the [home page](https://www.arduino.cc/en/Reference/LiquidCrystal) for the library to check-out many examples
- In our program, first we need to tell which pins of the Arduino are connected to the LCD display using *LiquidCrystal lcd(rs, enable, d4, d5, d6, d7)* function
 - Set this to *LiquidCrystal lcd(4, 5, 6, 7, 11, 12)* to reflect the pins we are using
- Lets improve the program we wrote and display the voltage on the LCD
 - We can use *lcd.setCursor(line,character)* to position our messages
 - We can use *lcd.print(message)* to display a message on the LCD screen (e.g. *lcd.print("Hello")*)

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name: S28

# Liquid Crystal Display (LCD) (P-II)

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# Bluetooth Communication  
### Sending Information to a Phone

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.logo-slide[]
.footer[[Duleepa J Thrimawithana](https://www.linkedin.com/in/duleepajt), Department of Electrical, Computer and Software Engineering (2021)]

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# Bluetooth Communication with Phone (P-I)

-	Bluetooth modules can communicate with the Arduino Nano using serial
-	Since we already use the default serial to communicate with PC we have to use a software serial 
-	Fortunately, we are going to use an existing software called AltSoftSerial to help us
-	Go to Tools > Manage Libraries, find AltSoftSerial and install it so we can use it in our project
-	We can now setup AltSoftSerial communication at 9600 bps to communicate with the Bluetooth module  
 -	Connect the Bluetooth module to header pins labeled “P1” 
- Lets have a counter that counts up every second upto 10 and send this counter value to the phone
 - The phone will receive the counter value every second
 - Display the counter value also on the PC so we can *debug* our code 
-	On your phone, download a *BluetoothLE* app to view the message sent by the Arduino 
 - Once you pair the Bluetooth module with the phone via the BluetoothLE app, the blinking red light will stay on indicating successful pairing

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name: S28

# Bluetooth Communication with Phone (P-II)

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# Temperature Sensors and Tachometers   
### Measuring Temperature and Speed

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.logo-slide[]
.footer[[Duleepa J Thrimawithana](https://www.linkedin.com/in/duleepajt), Department of Electrical, Computer and Software Engineering (2021)]

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name: S35

# Measuring Battery Temperature

.left-column[
- There are many types of temperature sensors
- TMP36 is one of the easiest to use
- It needs a 5V supply and a ground connection
- The voltage at the center pin will change by 0.01V per every degree starting from 0.5V at 0 degrees C
 - For example if the temperature is 25 degree C the TMP36 sensor will show 0.75V (i.e. 0.5 + 0.25V)
- The black plastic case of the TMP36 sensor should be touching the hot surface to be measured 
- We can connect the TMP36 (or any other sensor) to the "EvoSens Board" using the header P2
 - Pins 2 to 3 of this header connects to A6 to A3 of Arduino

]

.right-column[
.center[
<img src="img/tmp36.png" class="noborder" alt="TMP36 Sensor" width="300px"/>
]
]

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name: S35

# Connecting the TMP36 Sensor

- Lets connect the pins 1, 2 and 6 of P2 on the "EvoSens Board" to pins 1, 2 and 3 of the TMP36
 - The voltage at the center pin of TMP36 can be read using *analogRead(A6)* function

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name: S31

# Measuring Vehicle Speed & Acceleration

.left-column[
- Typically we use a tachometer to measure how fast a wheel spins 
 - Rotational speed (`$ \omega_{wheel} $`) and acceleration (`$ \alpha_{wheel} $`) of the wheel is then converted linear speed (`$ v_{cart} $`) and acceleration (`$ a_{cart} $`) since we know the radius (`$ r $`) of the wheel
\\[v\_{cart} \approx  \omega\_{wheel} \times r \quad  \text {&} \quad a\_{cart} \approx \alpha\_{wheel} \times r \\]
- Alternatively a GPS can be used to measure the speed and acceleration 
 - GPS modules that interface with [Arduino are available](https://create.arduino.cc/projecthub/ruchir1674/how-to-interface-gps-module-neo-6m-with-arduino-8f90ad) or a phone with an appropriate app can be used 
- Motor controllers can predict the speed using for example the sensors in the motor 
 - Depends on type of motor and controller you use
]

.right-column[
<br>
<br>
<img src="img/MagneticSpeed.png" class="noborder" alt="V & I Sensor" width="350px"/>
]

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name: S32

# Tachometers

.left-column[
- Commonly tachometers either use magnetism of light to measure the rotational speed of a wheel 
- A tachometers that relies on light to measure the speed of a wheel use a device called a photo interrupter 
- A photo interrupter consist of 
 - Light emitting diode (LED) to generate a light source (a light beam)
 - A light detector like a photo diode or photo transistor 
- Photo interrupters are very cheap 
- A more advanced version of a tachometers are also called shaft/rotary encoder
 - They can also predict the precise location of the wheel 
]

.right-column[
.center[
<img src="img/photoint2.jpg" class="noborder" alt="Sensor" width="130px"/>
.zoom175[
<img src="img/PhotoInt.jpg" class="noborder" alt="Photo Sensor" width="320px"/>
]
]
]

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name: S33

# How to Use a Photo Interrupter (PI)

.center[
<img src="img/SpeedSensor.png" class="noborder" alt="Speed Sensor" width="400px"/>          
<img src="img/PhotoInt.jpg" class="noborder" alt="Speed Sensor" width="400px"/>
]

- LED needs to be powered (e.g. using a 5V supply and a current limiting resistor)
- Light detector may also need a power supply to function (typical a 5V supply) together with a measurement resistor 
- When light from the LED reaches the detector through the slots in the disk attached to wheel the photo interrupter produces a signal

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name: S34

# How to Use a Photo Interrupter (PII)

.center[
<img src="img/SpeedSensor.png" class="noborder" alt="Speed Sensor" width="380px"/>          
<img src="img/PhotoInt.jpg" class="noborder" alt="Speed Sensor" width="380px"/>
]

- When slots are out of alignment, no light reaches the detector 
- Photo interrupter outputs a stream of high and low pulses that can be counted to determine the speed
- Number of pulses depends on the number of slots (`$ N_{slots} $`) in the disk
- The rotational speed is then simply 
\\[ \omega\_{wheel} = 2\pi / (\text{Time Period of a Pulse} \times N_{slots}) \\]

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# Acknowledgements
#### Special thanks to Wai Yeung, Ryan Kurte, Andrew Chen & Hamish O'Neill from the 
#### Electrical, Computer & Software Engineering department at The University of Auckland 
#### for their support in preparing this material.

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# Questions?
### Thank you