Advisor: Tao Zhang

EENG-491-w02

Advisor: Tao Zhang

Member: Haotian Kong, Rui Xue, And Ji Dai

May 13, 2013
Table of Contents

1. 
   Introduction ………………………………………………… 3-4
   
   1. 
      Background ………………………………………………... 3
      
   2. 
      Motivation ………………………………………………………...… 3
      
   3. 
      Objective ……………………………………………………………… 3
      
2. 
   Design Approach ………………………………………….…. 4-5
   
3. 
   Key factors on the research ………………………….…………...5-9
   
   1. 
      Influence of alcohol on human ……………………..………….....5-6
      
   2. 
      Alcohol Concentration change in weight…………………………..6-8
      
   3. 
      The time after one drank ……………….………………….…….8
      
   4. 
      Law of different countries ………………………….…………………..9
      
4. 
   Hardware ……………………………………………………...…9-14
   
   1. 
      MQ3-sensor ………..………………………….…………………….....9-11
      
   2. 
      Arduino Mega …………………………………………………….12-13
      
   3. 
      BlueSmirf Silver Module ………………………….…………………13-14
      
5. 
   Software……………………………….…………..……………15-18
   

5.2 Android Programming ……………………………..……………….…..16-18

6. 
   Project Demonstration …………………………………………..19-20
   
7. 
   Future Plan ………………………………………………...20-22
   
8. 
   Cost …………………………………………………………22
   
9. 
   Summary …………………………………………………....22
   
10. 
    References and Attachments ………………………………….…23-29
    

1. 
   INTRODUCTION
   
   1. 
      Background
      

2. 
   Motivation
   

3. 
   Objective
   

1. 
   Sensor Part--used to detect the concentration of alcohol in the air and send the concentration in the form of voltage signals to the following part.
   
2. 
   Processing Part—used to receive the voltage signals and process the signal to analog signals that can be standard for the concentration of alcohol.
   
3. 
   Display Part—used to get the processed signal and show the data to users in the form of diagrams.
   

The system should be safe, sensitive, accurate, convenient and cheap. This kind of system can be fixed on every car to ensure the driver’s driving safety and can protect the passengers’ walking safety.

2. 
   DESIGN APPROACH
   

Figure 1.flow chart of Alcohol detecting system

1. 
   MQ-3 alcohol sensor: This sensor can detect the value of the alcohol concentration in the air and transform this value to voltage signals. The sensor should be powered and the pin on the sensor which is used to send out the voltage signals should be connected with the analog-in pin on the Arduino board. 
   
2. 
   Arduino board: We chooses the Arduino Mega ADK as the developing board for it has more pins and has more advanced chip with more flash memory which can reach almost all of our requirements in the research period. With the help of Arduino board, we can transform the uncountable voltage signals to countable analog signals which range from 0 to 1023. The operating voltage is 5V. So the real voltage of the input voltage is:  (Output analog value/1024)*5V.  After the Arduino board has completed the data processing part, it would send the signals to the cellphone with the help of Bluetooth module. 
   
3. 
   Bluetooth module: Bluetooth module can help the system reach wireless connection. This means we needn't take pains to try to connect the cellphone with Arduino board by cockamamie wires. This design can let the system become more humanized.
   
4. 
   Android phone: Smart phone is a wide platform for developers to design applications. We have designed an application that can let the value of alcohol concentration showed in visual diagrams instead of analog signals. And because the cellphone is a good medium that can contact with others by messages or the Internet, the statistics can be shared easily.
   

3. KEY FACTORS ON THE RESEARCH

—Blood Alcohol Concentration

3.1 Influence of alcohol on human

Alcohol will influence human’s behavior. One drinks more, one would be dizzier. Terrible traffic would occur because of drunk driving. From the chart blows, we can see the influence of alcohol on human behavior in details.

0.02 — 0.03 BAC: No loss of coordination, slight euphoria and loss of shyness. Depressant effects are not apparent. Mildly relaxed and maybe a little lightheaded.

In sum, alcohol will negatively affect your behavior. The more you drink, you will be more easy to be wild.

3.2 Alcohol Concentration change in weight

There are far variables involved to accurately estimate or predict a person’s BAC simply based on gender. The data is so important for us to build a accurate project design.

Figure 17.Concentration of alcohol vs. consume number and weight-men

Figure 18.Concentration of alcohol vs. consume number and weight-women

The drink chart displayed above provides a rough estimate of a person's blood alcohol level (BAC). it is based on the number of drinks consumed and the person's weight. The red number in men chart shows you cannot drive in such a concentration. The purple number in women chart means you have out of control and driving skills have been significantly affected. The bigger you are, the more difficult you will get drunk. Our design is open to all people, so we consider the weight into account.

3.3 The time after one drank

As the following figure19, it’s also an important factor for calculating the concentration of alcohol in one’s body. From the chart above we find the relationship versus the weight and the consumed number. One will get lower concentration of alcohol as time passes, which will affect the measurement of our system. Based on the chart, we calculate the relationship between the concentrations of alcohol and the time after you drank.

Figure 19. Hours to zero BAC for men and women

3.4 Law of different countries

Figure 20. Different standard among different countries

1. 
   MQ3-sensor
   

In this sensor, there’s a little white tube in the middle of sensor. Basically, this tube is a heating system that is made of aluminum oxide and tin dioxide and inside of it there are heater coils, which practically produce the heat. And you can also find 6 pins. 2 pins that I called Pin H are connected to the heater coils and the other ones are connected to the tube.

The core system is the cube. As you can see in this cross-sectional view, basically, it is an Alumina tube cover by SnO2, which is tin dioxide. And between them there is an Aurum electrode, the black one. And also you can see how the wires are connected. Basically, the alumina tube and the coils are the heating system, the yellow, brown parts and the coils in the figure2

Figure 2. Inside the sensor

The MQ-3 is an alcohol gas sensor that is available for about $5 from sparkfun. It’s easy to use and has sparked the imagination of anyone who has dreamed of building their own Breathalyzer device for measuring the amount of alcohol in the human body. We got five MQ-3 sensors a couple of months ago and have spent a lot of time trying to figure out how to do this. After lots of “data gathering”, we found that this task is not as easy as it sounds.

4.1.2 Circuit of sensor connection of MQ3

As shown in Figure3, The other part of the circuit is essentially a variable resistor inside the sensor. The resistance across an A pins and a B pin varies depending on how much alcohol is in the air in the sensor. The more alcohol, the lower the resistance is. We measure alcohol in the breath by measuring this resistance. Instead of measuring the resistance directly, we measure the voltage level at the point between the sensor and a load resistor.

First, we use 5v. And as you can see one of H pins goes to the power and the other one is connected to the ground. And the pin A is connected between the power and the pin H and the pin B is goes to the microcontroller. Also between the ground and the Arduino, you need the resistor. Before you connect the resistor if you use the pot, you can tune the resistor for getting more accurate values. In the datasheet they say you can used 100k om to 470k om. So we use 220k om in our circuit.

It will react that depending on the environment, it gives us little bit of different values. But in our experiment, it gives me 200 as the lowest value and 700 as the highest value. And when it detects the alcohol in the air, actually it is pretty sensitive, the value gets higher very quickly but you have to wait for about 10 seconds to reset it. So that means getting values is fast. And the sensitivity of this sensor is affected by time span. When I used three different sensors, the range of value was a little smaller than the new one's. But it doesn’t affect the whole experiment.

4.1.3 Reaction Theory of MQ3

SnO2 ceramics will become the semi - conductor, so there are more movable electrons, which means that it is ready to make more current flow.

Then, when the alcohol molecules in the air meet the electrode that is between alumina and tin dioxide, ethanol burns into acetic acid then more current is produced. So the more alcohol molecules there are, the more current we will get. Because of this current change, we get the different values from the sensor.

4.1.4 Detail of Sensor Connection

As the figure 4 shown, We put the H (left) connect the 5.0V and H (right) to the ground (GND). We can choose either A or B as one of the analogin pin to connect the Arduino board. And use another one, B or A, just opposite to the former one, we can only use 4 of 6 pins in the project.

4.2 Arduino Board

4.2.1 Introduction of Arduino mega

Arduino Mega2560 microcontroller board is an easy-to-use development board based on the Atmel ATmega2560 MCU. The ATmega2560 has 256 KB of flash memory for storing code (of which 8 KB is used for the bootloader), 8 KB of SRAM, and 4 KB of EEPROM. The Arduino Mega2560 microcontroller board has 54 digital input/output pins (of which 14 can be used as PWM outputs), 16 analog inputs, 4 UARTs (hardware serial ports), a 16 MHz crystal oscillator, a USB connection, a power jack, an ICSP header, and a reset button. The Arduino Mega2560 contains everything needed to support the MCU. Simply connect it to a computer with a USB cable or power it with a AC-to-DC adapter or battery to get started. This Arduino development board is compatible with most shields designed for the Arduino Duemilanove or Diecimila. The Arduino Mega2560 differs from all preceding boards in that it does not use the FTDI USB-to-serial driver chip. Instead, it features the Atmega8U2 programmed as a USB-to-serial converter. The Arduino MCU board includes a number of facilities for communicating with a computer, another Arduino, or other MCUs.

4.2.2 Sampling rate in the Design

Delay() is a key function to arrange the frequency of reading in the while loop.

Once the loop starts, the analogRead() function will sample the data from sensor and by delay(100) function, delay 100ms, then next sample data comes in.

In our project, we use the analogread() in the arduino, the Arduino board contains a 16 channel (8 channels on the Mini and Nano, 16 on the Mega), 10-bit analog to digital converter. It will map input voltages between 0 and 5 volts into integer values between 0 and 1023. It gives us readings of: 5 volts / 1024 units or, .0049 volts (4.9 mV) per unit. The input range and resolution can be changed using analogReference().

It takes about 100 microseconds (0.0001 s) to read an analog input, so the maximum reading rate is about 10,000 times a second. It returns int (0 to 1023).

4.3 Bluetooth Silver Module

Here’s the Connection the bluesmirf silver Bluetooth, as shown in the figure 6. There’re 6 pins in the Bluetooth Silver Module, we use the middle of them, the sequence is VCC, GND, TX and RX, TX and RX means the transmit port and receive port which should be connect to the receive port and transmit port in the arduino board.

As the following figure 7 and figure 8, BlueSmirf Bluetooth Module should have 115200 baud rate which should modify before we use it. When the BlueSmirf Bluetooth Module paired with your device, the green light is on. The picture Figure 7, shows the baud rate in the arduino code, the figure 8, shows the reading board in the computer.

5.1 setting of environment

5.1.1 Arduino software

It is the most complicated part of this experiment. We get the detailed tutorial from http://arduino.cc/en/main/software. There’re four kinds of operating system for you to choose. Basically, the software helps us input the code into the arduino board, which shows the corresponding alcohol reading result of MQ3 (sensor).

As shown in figure 9, after placing the folder into the libraries folder, we should be able to access all the amarino files through the arduino programming environment and then open the code in arduino board.

Figure 9: SensorGraph code in Arduino

5.1.2 Installing Amarino

We download the following applications on your mobile phone

1. 
    Amarino – Android Application- to be installed on phone.
   
2. 
   Amarino Plug-in Bundle- to be installed on phone.
   
3. 
   Amarino Library- To be kept in Java Project
   

It is the most complicated part of this experiment. The basic idea is to Install the Eclipse first (follow the system requirements), then install the android SDK, then install ADT plugin for Eclipse IDE. Codes still need to be changed to realize the function and is shown in the end of the manual.

5.2.1 Structure of Android programming

Android programming based on the Java SE platform, we design the project as seven parts, Alarm, Amarino, AmarinoIntent, Country, GraphView, SensorGraph and StartingPart.

Figure 11. The brief structure in Android programming

The Country.java and StartingPart.java, we set these activities to let the user choose the country they have to fit the different criteria the application has. As you can see in the following picture:

When you want to arrange the sequences of your activities (it’s the name of android interface), it should be set in the AndroidManifest.xml, that’s the different between Java and Android.

And In order to let the country.java become the first, we should press the following code, let the inside the first activity we want to show to the user.

Then the GraphView.java and SensorGraph.java shows the actual diagram can show to the user,

Then open the apk file and install the application “alcohol detection” into smart phone. We use the Samsung S1 GT-I9100 android version is 4.2.2, processor is ARmv7 Processor rev 1(v71).

1. 
   In the code part, in order to make the activity act like a window, not extend the whole screen, we can set the androidManifest.xml as /theme.Dialog.
   

2. 
   When we use the application in virtual smart phone, it may show us the error process, as shown in the figure 16.
   
3. 
   We should check the androidManifest.xml to make sure that each activity has settled already.
   
4. 
   Layout is a very important part in android design, the label and arrangement of buttons and texts are all depend on these file, when we set the function in activity, we should set the corresponding part in Layout, and then, it will yield the ID in the “R.class” in Gen fold. And during the programming, R.class will disappear automatically, then we found if you have unlogical code in layout.xml, it can be done.
   

6. PROJECT DEMONSTRATION

From the demonstration we can see that our alcohol detecting system has the following advantages:

1. 
   The materials are cheap and are easy to acquire. The cost of this system is one of the important factors we are considering. Because if we want to popularize this system, we should make it as cheap as possible so that every driver can afford of this useful system.
   
2. 
   It doesn’t some large measuring instruments which mean it can be made small enough and can be put into production without any challenging technological problems.
   
3. 
   We used the Bluetooth module. It can realize the wireless communication. It is a significant design because we can use the smart phone to receive the signals and do further designs.
   
4. 
   Smart phone is a wide platform for us to design more humanized applications to fulfill user’s requirements. In our system, we have transformed the abstract analog signals to visual diagrams. And the smart phone will send alarm to users when the alcohol concentration reaches a certain value.
   
5. 
   We can also share the value of alcohol concentration from the drivers to their relatives, friends or the police. Because the data can be showed on cellphones, we can send the date by the Internet or message.
   

7. FUTURE PLAN

These are what we have done up to now. In the future, we will:

1. 
   Try to reduce the cost of the system when it can be made as a product.
   

2. 
   Make it small enough and more convenient to use.
   

1. 
   The first option is that we can set it on the keychain, the system is as small as a key and the driver can blow it directly. So the drivers won’t take pains to refit the car.
   
2. 
   Another option is that we can put a cable near the driver’s seat and the cable is connected with the ignition of the car. This means the alcohol detection system can be another key to the car. The driver should blow to the system before he/she start the car. If the value of the alcohol concentration is above a certain value, the system will stop the car starting. So a drunk driver won’t be able to start the car which will prevent the behavior of drunk driving. It is not only safe to the driver, but can ensure the passengers won’t be hit because of the driver’s drunk driving.
   

Figure 22. Connect with car ignition

3. 
   We can also design it as a plug-in unit. It can be plugged with a cellphone or on the console of the car. This design can ensure a tiny size of the system. And the system can be used as an USB stick that means the data can be stored in it and we can plug it with relevant terminal to do more calculations.
   

Figure 23. Plug the iphone

4. 
   Fixing the alcohol detection system on the driver’s seat is also a wise choice. Because the sensor near the seat can detect the driver’s breathe alcohol concentration easily and the driver won’t take pains to blow to any system intentionally.
   

Figure 24. Fix on the back

Whether the system is accurate and sensitive can affect whether the users are satisfied with it. Our system should tell the drivers the real alcohol concentration and whether they can control their driving skill after they have drunk some wines. Our system shouldn’t bring trouble to the users. Such as the system sends alarm continually and can’t be stopped.

7.4 Raise its popularity by advertisements so that it can be used on every car.

It is no doubt that if a product is wanted to be popularized, it should be advertised well. Our system is focus on detecting the driver’s alcohol concentration which can be used on everyday life. So we should tell drivers how dangerous the drunk driving will be and how to avoid this by fixing a tiny, cheap and accurate system. We are always thinking about how to construct a safe driving environment to drivers.

8. COST

Figure 25. Total cost for project

In this project, the most important thing is that the sensor can detect all the conditions when driver has drunk already no matter how much they did. Secondly, connecting to the car ignition is a proper way to force driver do so every time they want to drive. Thirdly, user can get the data on their android phone in time when they do breathing test every time.

We predict that alcohol detecting system can use in all cars to serve for the people who need.

10. REFERENCES AND ATTACHMENT

1. "Sensor Report - MQ3 Gas sensor", April 27, 2008

2. 
   "The Jacket That Tells You You’re Drunk", October 13th, 2011
   

3. Blood/Breath Alcohol Concentration (BAC) calculator

4. "Arduino Breathalyzer: Calibrating the MQ-3 AlcoholSensor"

http://nootropicdesign.com/projectlab/2010/09/17/arduino-breathalyzer/

5. "Building an Breathalyzer with MQ-3 and Arduino", Mar 7, 2010

Manual of Alcohol Detecting System

It’s a kind of system that detect the alcohol concentration in the cars to prevent the behavior of drunk driving.

1. 
   android smart phone (samsung galaxy S1)
   
2. 
   OSX operating system
   
3. 
   Arduino mega
   
4. 
   Eclipse IDE for Java EE Developers
   
5. 
   Android SDK
   
6. 
   Amarino Tookit
   
7. 
   Bluetooth Medium- Bluesmirf Silver
   

We separate it as three parts: Laptop part, hardware part, software part

Connect the Arduino borar and MQ3 in the following way:

H (left)–5.0V

H (right)-GND

A (one of both A) — 5.0V

B — GND

It is the most complicated part of this experiment.

You can get a detailed tutorial from http://arduino.cc/en/main/software

There’re four kinds of operating system for you to choose

Basically, the software helps us input the code into the arduino board, which shows the corresponding alcohol reading result of MQ3 (sensor)

Step 3 : Downloading Meet Arduino Library (Laptop part)

Download the MeetAndroid Library and place it into the libraries Folder Arduino.

After placing the folder into the libraries folder, you should be able to access all the amarino files through the arduino programming environment.

Or import the code (sensorgraph) that lists below

Connect the bluesmirf silver Bluetooth adapter in the following way:

Tx–1 to Rx–0

VCC — 5.0V

GND — GND

TX — RX (digital pin 0 of arduino)

RX — TX (digital pin 1 of arduino)

• 
  * very very important: Your BlueSmirf Bluetooth Module should have 115200 baud rate. When the BlueSmirf Bluetooth Module paired with your device, the green light is on.
  

Go to http://www.amarino-toolkit.net/ and download the following applications on your mobile phone

a. Amarino – Android Application- to be installed on phone.

b. Amarino Plug-in Bundle- to be installed on phone.

c. Amarino Library- To be kept in Java Project
Step 6 : Test the communication between Blue smirf module and Arduino (laptop part)

Seek the open source at http://www.amarino-toolkit.net/index.php/getting-started.html

Note: set the Serial Monitor Baud rate to 115200. Code lists in the below:



Step 7 : Set up Eclipse (software part)

It is the most complicated part of this experiment.

You can get a detailed tutorial from http://developer.android.com/sdk/eclipse-adt.html#installing

The basic idea is to Install the Eclipse first(follow the system requirements), then install the android SDK, then install ADT plugin for Eclipse IDE.

There is an open source of Sensor Graph, down load from http://code.google.com/p/amarino/downloads/detail?name=SensorGraph_02.zip&can=2&q=

Codes still need to be changed to realize the function and is shown in the end of the manual.

Step 9 : Set up the application on the phone (software part)

NOTE: you must have ADT-Plugin installed.

Go to http://developer.android.com/sdk/eclipse-adt.html

*make sure you have your “AmarinoLibrary_v0_55.jar ” file is included. Download it

Your phone should already be connected via usb to your computer, In your phone settings , and install from unknown sources checked.

In Samsang S1, it was in settings>applications>USB debugging.
 Next, find alcohol detecting.apk that imports to your phone.

This will install the Alcohol detection app to your phone and run it.