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POSITION DETECTION USING ULTRASONIC SENSORS

INSTRUMENTATION &

CONTROL

INSTRUCTOR: OSMAN PARLAKTUNA

26.01.2004

MAHMUT SERKAN ÖZKAN CELAL METEHAN AYDIN

ALİ ÖZDEMİR

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INDEX

I. PROJECT DESCRIPTION: 3

II. PROCESS: 3

III.HARDWARE: 5

A. ULTRASONİC SENSORS: 5 B. MICROCONTROLLER, PIC 7 C. MAX 232 8 D. PC 8

IV.SOFTWARE: 9

A. FLOW CHART FOR PIC: 10 B. FLOW CHART FOR PC: 11

V. CONCLUSION: 13

VI.APPENDIX A: URF SRF04 PIC 16F877 CODE 14

VII. APPENDIX B: PROGRAM FOR PC 18

VIII. APPENDIX C: REFERENCES 30

IX.APPENDIX D: COST 31

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I. PROJECT DESCRIPTION:

Our project is position detection using ultrasonic sensors. Briefly; we try to measure the

distance of an object from an ultrasonic sensor and map its position in a precalculated area. We use

SRF04 ultrasonic sensors for distance measurement and drive this sensor via PIC (Peripheral Interface

Control) 16f877 microcontroller. After getting the necessary data from sensor we make serial

communication between PIC and PC and than mapping in PC using Visual Basic. We will first

describe you the process than hardware that are used in our project and than talk about the software

implementation and finally an evaluation about project.

II. PROCESS:

At the beginning of semester we try to decide which type of hardware to buy. Initially

we want to use Polaroid 6500 ultrasonic module which exist in laboratory. Also one advantage of

Polaroid is we make it work and search on how it works. After that we see that there will be lots of

problems while using Polaroid. First one is its power problem. It requires 2A current which is very

high for electronic applications. Also it has got serious connector problems between transducer-driver

circuit and between control pins -power circuit. Than we search on and try to find another ultrasonic

sensor module. After searching we find SRF04 which is economical in power consumption also

smaller in size and easily controllable. We buy sensors via visa card from internet site www.robot-

electronics.co.uk.

Next stage for us is deciding on what kind of microcontroller we use. You can think of

why we use microcontroller instead of directly connecting SRF04 to PC that contains A/D card. We

use microcontroller because in timing measurements we need 66us sensitivity that can not be provided

high-level languages. We initially think of Intel 8051 microprocessor. Again we search and find that

PIC 16F877 microcontroller is much more suitable for our application.

After we got sensors and our 16F877 we start on working. Initially we test sensors. We

test how they work, and apply signals that are at different frequency. We find at what frequency we

need to trigger sensors. Apart from this we test ECHO signal and find sensitivity approximately.

Our test data is shown below:

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In software part we try to develop algorithms for both triggering sensor via PIC and

reading echo signal with PIC. After making PIC work we try to develop algorithm on PIC-PC serial

communication. And lastly we develop codes for data processing on PC that converts time data to

distance and map position on the screen. The diagram below shows us the general working principle of

our system as schematic.

In next stages we will describe the hardware and software parts in detailed.

Test Range Measured Detection Distance

Echo Output High Time

1 7.5 cm 500 us 2 15 cm 1000 us 3 30 cm 2000 us 4 60 cm 4000 us 5 100 cm 6600 us

PC SRF04 PIC

Serial communication, Read ECHO pulse width in time domain.

Trigger

Read ECHO pulse width

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III. HARDWARE:

We try to calculate the distance of an object using ultrasonic sensor, microcontroller and

mapping with PC.

A. Ultrasonic Sensors:

The principle of working of an ultrasonic sensor is easy. The sensor transmits ultrasonic sound

waves and waits for reflected sound waves. After receiving reflected sound wave or usually named

echo, sensor detects the distance in different ways. In our project we use SRF04 ultrasonic sensors.

As seen in the figure it seems easy to use SRF04 ultrasonic sensor. Its main advantage is the

number of pins that you have to use is only 4. One for Vdd, one for Vss, one for Trigger and one for

Echo. Also one additional pin is given to adjust the range of the sensor. The other specifications of

SRF04 ultrasonic sensors are

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Voltage - 5v only required

Current - 30mA Type. 50mA Max.

Frequency - 40 KHz

Max Range - 3 m

Min Range - 3 cm

Sensitivity - Detect 3cm diameter broom handle at > 2 m

Input Trigger - 10uS Min. TTL level pulse

Echo Pulse - Positive TTL level signal, width proportional to range.

Small Size - 43mm x 20mm x 17mm height

The important part for us is the signal conditioning of SRF04. We trigger the sensor and then

wait for echo pulse. Measuring echo pulse width is important for us because 66.4 us means us 1 cm.

As seen from timing diagram of SRF04 after triggering sensor with a TTL logic 1 (we use 5 V)

at least 10 us, sonic burst module embedded in sensor makes 8 cycle sonic burst at 40 kHz. After the

last sonic burst go low our echo signal became high and stay high until any reflected sound received

by the sensor. Our initial objective is to trigger the sensor and than read the echo signal and measure

its pulse width.

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B. MICROCONTROLLER, PIC In this project we initially can not decide which microcontroller we will choose. We think of

Intel 8051 or PIC. After researching on the net we decide to use PIC. PIC as its name implies

(Peripheral Interface Controller) is designed by Microchip firm especially for Peripheral Interface

jobs. Its main advantage is its memory structure. It has got Banks that shows each special register

address (file registers). As PIC produced by RISC (Reduced Instruction Set) architecture we can see

Harvard architecture that means the controller has got separate program memory which makes it faster

than any other controller. One of the most important work is to chose the correct model that will

support our project. For serial communication with PC we need Universal Synchronous Asynchronous

Receiver Transmitter (USART/SCI) property. So we choose 16F877 which has got these properties.

Our PIC has a 8K program memory which enables us write programs without thinking the

capacity. Also we can use 14 external interrupts with this model. Additionally we have 5 ports (a, b, c,

d, e), 3 timers, 2 counters and only 35 instructions to program.

Our connection diagram is shown below:

As shown we will use INIT1, INIT2, INIT3 to trigger the sensors and RC1 to read the ECHO1,

ECHO2, and ECHO measuring the pulse width and make necessary operations we will send the data

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through MAX232 with TX/CK Pin (25) .

C. Max 232

The MAX232 family of line drivers/receivers is intended for all EIA/TIA-232E and V.28/V.24

communications interfaces, particularly applications where ±12V is not available. This part is

especially useful in battery-powered systems, since their low-power shutdown mode reduces power

dissipation to less than 5µW. The MAX232, use no external components and are recommended for

applications where printed circuit board space is critical.

Superior to Bipolar

_ Operate from Single +5V Power Supply (+5V and +12V—MAX232)

_ Low-Power Receive Mode in Shutdown (MAX232/MAX242)

_ Meet All EIA/TIA-232E and V.28 Specifications

D. PC We used a PC’s serial port to communicate between PIC and PC. The GUI (WYSIWYG) is :

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IV. SOFTWARE:

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A. Flow Chart for PIC:

At the beginning of the program we initialize the PIC’s ports and registers, and USART

configuration. Then PIC sends 150 ms trigger to the first SRF04 and listens the echo signal , after

that SRF04 measures the distance and sends it to PIC. Furthermore PIC starts to measure the pulse

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width of the received echo signal and transmits the pulse width to the PC. This routine repeated 2

times more.

B. Flow Chart for PC:

At the loading, the program search for available ports and displays them on the Com Port

frame. After that the user press the measure button, program starts a loop receives 16-bit serial data

(Mscomm32.ocx supports 8-bit but we implement a code to overcome this problem) and starts to

calculate. We observed calculated distance has a linear error so that we overcame this problem using

curve fitting. In Matlab we entered the data and using curve fitting tool to obtain the transfer function

which has minimum error. Furthermore using the Windows GUI’s (gdi32) we display the measured

object on the screen. Loop stops with the Stop button.

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V. CONCLUSION:

During this project we learned that ;

How bats measures the distance of an obstacle ?

How sonar sensor works ?

How Srf04 module works ?

How can we interface the Srf04 with PIC 16f877 Microcontroller ?

How to communicate between Srf04 and PC ?

Finally we implement our system on breadboard and see on the PC the position of an obstacle.

In fact, up to this point we suffer a lot. First problem we face is testing the sensors it takes much more

time than we think. Also code development process for PIC is another problem for us. This problem is

sourced by the necessity software development tools (PIC Programmer) that does not exist. At first we

download our code to PIC than after it is a problem to make changes on code. So we made up a PIC

16F877 programmer which is not working. Than we have to buy a programmer. Also we have got

problems on serial communication because of the regulating necessary baud rate.

In this project we gain lots of experience about project development process. Below you see

our system’s final schematic:

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VI. APPENDIX A: URF SRF04 PIC 16F877 CODE

;************************************************************ ; ; This is a program to run the PIC 16F877 to drive ; the SRF04. Port B will be used for the SRF04 module ; drive, and the CCP1 pin for echo signals. ; Below is the pin out ; ; PORTB... ; 0=INIT 1 ; 1=N/A ; 2=INIT 2 ; 3=N/A ; 4=INIT 3 ; 5=N/A ; 6=N/A ; 7=N/A ; ; CCP1=ECHO 1 , ECHO 2 , ECHO3 respectively. ; ;*********************************************************** list P=PIC16F877, F=INHX8M, C=160, N=77, ST=OFF, MM=OFF, R=DEC, X=OFF #include P16F877.inc ; this is the standard header file for 16f877 list list __config(_CP_OFF & _PWRTE_ON & _XT_OSC & _WDT_OFF & _BODEN_OFF) ;********************** EQUATES **************************** Bank0Ram equ H'20' MaxCount equ 50 ;*********************************************************** ;******************** VARIABLES *************************** cblock Bank0Ram MACRO_TEMP TEMP TEMP2 TIME1 ; this is the low byte for the Measured Signal TIME2 ; this is the high byte for the Measured Signal endc ;*********************************************************** ;****************** MACRO DEFINITIONS ******************* MOVLF macro literal,dest movlw literal movwf dest endm MOVFF macro source,dest movf source,W movwf dest endm DELAY macro time local Again

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movlw time movwf MACRO_TEMP Again decfsz MACRO_TEMP goto Again endm ;******************************************************** ;******************* VECTOR ************************** org H'000' ;reset vectors goto MainLine ;Branch past tables ;********************************************************* ;******************* END OF TABLE ********************* ;******************** MAIN ROUTINE ********************** MainLine call Initial ;initialize everything MainLoop call FIRE_1 ;fire module 1 MOVFF TMR1L,TIME1 ;save the low time MOVFF TMR1H,TIME2 ;save the high time call TRANSMIT ;transmit the data in Nibble1 - Nibble3 call LoopTime ;wait for 10ms call FIRE_2 ;fire module 2 MOVFF TMR1L,TIME1 ;save the low time MOVFF TMR1H,TIME2 ;save the high time call TRANSMIT ;transmit the data in TIME1 and TIME2 call LoopTime ;wait for 10ms call FIRE_3 ;fire module 3 MOVFF TMR1L,TIME1 ;save the low time MOVFF TMR1H,TIME2 ;save the high time call LoopTime call TRANSMIT ;transmit the data in TIME1 and TIME2

goto MainLoop ;*********************************************************** ;*********************** INITIAL SUB *********************** ; ; this will initialize all of the ports and etc. Initial bsf STATUS,RP0 ;set to Bank 1 MOVLF B'00000111',ADCON1 ;setting all AD pins to digital I/O MOVLF 160,TEMP2 ;setting LoopTime time clrf TRISA ;setting all port a to output clrf TRISB ;setting PORTB as out MOVLF B'00000100',TRISC ;all port c output, CCP1 in MOVLF B'11110000',TRISD ;all input for port d clrf TRISE ;all output for port e movlw 0x19 ; 0x0C=19200 baud (0x19=9600 baud) movwf SPBRG

movlw b'00100100' ; brgh = high (2) movwf TXSTA ; enable Async Transmission, set brgh movlw b'10010000' ; enable Async Reception bcf STATUS,RP0 ; RAM Page 0 movwf RCSTA

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clrf PORTA clrf PORTB clrf PORTC clrf PORTD clrf PORTE MOVLF B'10000000',RCSTA ;enable the serial port return ;************************************************************ ;****************** FIRE 1 SUBROUTINE ********************** ; This is used to set up and fire SRF04 1 ;********************* ------------------- ************************* FIRE_1

clrf TMR1H ;clear the timer 1 low byte clrf TMR1L ;clear the timer 1 low byte

clrf PORTB ;ready PORTB bsf PORTB,0 ;set INIT 1 call T20 ;delay for 20 us bcf PORTB,0 ;trigger low bcf PIR1,2 ;make sure CCP1 is clear ECHO1_LOOKING btfsc PORTC,2 ;testing CCP1 goto ECHO1_LOOKING ; If not keep looking TIMER incf TMR1L ;Increment the Low byte btfsc STATUS, Z ;Do we have Zero (Multiple of 256)? incf TMR1H ;Increment High byte (if necessary) btfsc PORTC,2 ;testing CCP1 goto TIMER ;make sure CCP1 is clear return ;************************************************************ ;****************** FIRE 2 SUBROUTINE ********************** ; This is used to set up and fire SRF04 2 ;********************* ------------------- ************************** FIRE_2 clrf TMR1L ;clear the timer 1 low byte clrf PORTB ;ready PORTB bsf PORTB,2 ;set INIT 1 call T20 ;delay for 20 us bcf PORTB,2 ;trigger low bcf PIR1,2 ;make sure CCP1 is clear ECHO2_LOOKING btfsc PORTC,2 ;testing CCP1 goto ECHO2_LOOKING TIMER2 incf TMR1L ;Increment the Low byte btfsc STATUS, Z ;Do we have Zero (Multiple of 256)? incf TMR1H ;Increment High byte (if necessary) btfsc PORTC,2 goto TIMER2 return ;*********************************************************** ;****************** FIRE 3 SUBROUTINE ********************** ; this is used to set up and fire SRF04 3

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;********************* ------------------- ************************** FIRE_3 clrf TMR1L ;clear the timer 1 low byte clrf PORTB ;ready PORTB bsf PORTB,4 ;set INIT 1 call T20 ;delay for 20 us bcf PORTB,4 ;trigger low bcf PIR1,2 ;make sure CCP1 is clear ECHO3_LOOKING btfsc PORTC,2 ;testing CCP1 goto TIMER3 goto ECHO3_LOOKING TIMER3 incf TMR1L ;Increment the Low byte btfsc STATUS, Z ;Do we have Zero (Multiple of 256)? incf TMR1H ;Increment High byte (if necessary) btfsc PORTC,2 goto TIMER3 return ;*********************************************************** ;***************** TRANSMIT SUBROUTINE ********************* ; ; This is used to send the data that is stored in ; TIME1 (low byte) and TIME2 (high byte) out the ; serial port. ;*********************************************************** TRANSMIT movf TMR1H,0 btfsc STATUS,2 movlw b’11111111’ movwf TXREG call TransWt ; wait until finished sending movf TMR1L,0 movwf TXREG call TransWt return ;**************** LoopTime SUBROUTINE ********************** ; This subroutine counts 10 mS ;*********************************************************** LoopTime decfsz TEMP2,F call T20 return ;*********************************************************** ;************* *** T20 SUBROUTINE ************************** ; This will use up 10 us of time to ignore the ; noise on the echo line from the fireing. ;************************************************************ T20 MOVLF 20,TEMP ;a counter HERE decfsz TEMP,F ;dec the counter goto HERE

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return ;********** WAIT UNTIL RS232 IS FINISHED SENDING ***********

TransWt bsf STATUS,RP0 ; RAM Page 1 WtHere btfss TXSTA,TRMT ; (1) transmission is complete if hi

goto WtHere bcf STATUS,RP0 ; RAM Page 0 return ;*********************************************************** ;****************** END of ALL PROGRAMS ******************** end

VII. APPENDIX B: PROGRAM FOR PC FRMMAIN.frm

Private Sub btnRead_Click() Dim bytInput() As Byte Dim bytElemani As Byte Dim iX As Long Dim iY As Long Dim iL As Long Dim iP As Long Dim SeriSonuc As String Dim sHistory As String Dim SeriVeri As String Dim Comment As String If comSerial.PortOpen = False Then comSerial.PortOpen = True End If measure: Select Case comSerial.InBufferCount Case 0: MsgBox ("No data found") GoTo measure Case Is > 0: Say = comSerial.InBufferCount bytInput = comSerial.Input iX = UBound(bytInput(), 1) For iY = 0 To 1 If SeriSonuc <> "" Then If iY Mod 4 Then SeriSonuc = "" & SeriSonuc Else SeriSonuc = vbCrLf & SeriSonuc End If End If bytElemani = bytInput(iY) SeriVeri = Chr$(bytElemani) For iL = 1 To 8 SeriSonuc = Abs(CInt(BitOn(CLng(bytElemani), iL))) & SeriSonuc Next Next 'If BinaryToDecimal(SeriSonuc) * 6 > 4000 Then

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'txtsrf042.Text = "Cisim Bulunamadı" 'Else txtrec1.Text = SeriSonuc txtmea1.Text = ((BinaryToDecimal(SeriSonuc) * 6) / (166 / 2.54)) & " cm" txtypos.Text = BinaryToDecimal(SeriSonuc) / 40 + 6 'End If If txtmea1.DataChanged = True Then Comment = Now & " Received data ...: " & txtmea1.Text Close iFileNum SetLog (Comment) End If GoTo measure End Select End Sub Private Sub btnview_Click() frmObjDist.Show End Sub Private Sub clrlog_Click() On Error GoTo ErrorTrp del.DeleteFile ("data.txt") Exit Sub ErrorTrp: MsgBox ("History already cleared !!!") End Sub Private Sub Form_Initialize() BaudRate(0) = "110" BaudRate(1) = "300" BaudRate(2) = "600" BaudRate(3) = "1200" BaudRate(4) = "2400" BaudRate(5) = "9600" BaudRate(6) = "14400" BaudRate(7) = "19200" BaudRate(8) = "28800" BaudRate(9) = "38400" BaudRate(10) = "56000" BaudRate(11) = "128000" BaudRate(12) = "256000" End Sub Private Sub cmbBaudRate_Click() sBaudData = "" cmdUpdateBaud.Enabled = True End Sub Private Sub cmbBaudRate_KeyPress(KeyAscii As Integer) Select Case KeyAscii Case 48, 49, 50, 51, 52, 53, 54, 55, 56, 57 sBaudData = sBaudData & Chr$(KeyAscii) Case 13 sBaudData = "" UpdateBaud Case 127 sBaudData = "" Case 8 If sBaudData <> "" Then sBaudData = Left$(sBaudData, (Len(sBaudData) - 1)) End If

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Case Else sBaudData = "" End Select End Sub Private Sub cmbBaudRate_Change() Dim iX As Long Dim iL As Long Dim sCurrent As String If bLoaded Then cmdUpdateBaud.Enabled = True sCurrent = sBaudData iL = Len(sCurrent) For iX = 0 To 12 If sCurrent = Left$(BaudRate(iX), iL) Then cmbBaudRate.Text = BaudRate(iX) cmbBaudRate.SelLength = Len(cmbBaudRate.Text) Exit Sub End If Next End If End Sub Private Sub cmdUpdateBaud_Click() UpdateBaud End Sub Function BitOn(Number As Long, Bit As Long) As Boolean Dim iX As Long Dim iY As Long iY = 1 For iX = 1 To Bit - 1 iY = iY * 2 Next If Number And iY Then BitOn = True Else BitOn = False End Function Private Sub VerifyPorts() Dim sPort As String Dim iX As Long Dim iY As Long Dim lngType As Long Dim lngValue As Long Dim sName As String Dim sSwap As String ReDim varResult(0 To 1, 0 To 100) As Variant Const lNameLen As Long = 260 Const lDataLen As Long = 4096 sSubKey = "Hardware\Devicemap\SerialComm" If RegOpenKeyEx(lMainKey, sSubKey, 0, KEY_READ, hnd) Then Exit Sub For iX = 0 To 999999 If iX > UBound(varResult, 2) Then ReDim Preserve varResult(0 To 1, iX + 99) End If sName = Space$(lNameLen) ReDim binValue(0 To lDataLen - 1) As Byte If RegEnumValue(hnd, iX, sName, lNameLen, ByVal 0&, lngType, binValue(0), lDataLen) Then Exit For varResult(0, iX) = Left$(sName, lNameLen) Select Case lngType

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Case REG_DWORD CopyMemory lngValue, binValue(0), 4 varResult(1, iX) = lngValue Case REG_SZ varResult(1, iX) = Left$(StrConv(binValue(), vbUnicode), lDataLen - 1) Case Else ReDim Preserve binValue(0 To lDataLen - 1) As Byte varResult(1, iX) = binValue() End Select Next If hnd Then RegCloseKey hnd ReDim Preserve varResult(0 To 1, iX - 1) As Variant ReDim Ports(iX - 1) For iX = 0 To UBound(varResult, 2) sPort = Mid$(varResult(1, iX), 4, 1) Ports(iX) = sPort Next iY = UBound(Ports) For iX = 0 To (iY - 1) If Ports(iX + 1) < Ports(iX) Then sSwap = Ports(iX + 1) Ports(iX + 1) = Ports(iX) Ports(iX) = sSwap iX = -1 End If Next End Sub Private Sub UpdateBaud() Attribute UpdateBaud.VB_Description = "Changes the baud rate of the serial port" Dim sNewBaud As String Dim sOldBaud As String Dim sTmp As String Dim iX As Long On Error GoTo ErrTrap sNewBaud = cmbBaudRate.Text For iX = 0 To 12 If BaudRate(iX) = sNewBaud Then Exit For Else If iX = 12 Then MsgBox "Invalid Baud Rate, Please Try Again !", vbInformation, "Data Entry Error !" sBaudData = "" cmbBaudRate.Text = "" cmdUpdateBaud.Enabled = False Exit Sub End If End If Next sTmp = comSerial.Settings sOldBaud = Left$(sTmp, (InStr(1, sTmp, ",", vbBinaryCompare) - 1)) sTmp = Replace(sTmp, sOldBaud, sNewBaud, , , vbBinaryCompare) comSerial.Settings = sTmp cmdUpdateBaud.Enabled = False sBaudData = "" UpdateSettings Exit Sub

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ErrTrap: MsgBox Err.Number & " " & Err.Description & vbCr & " Error Generated By " & Err.Source, vbCritical, _ "System Error Trap !" End Sub Private Sub cmdExit_Click() Unload Me Set frmMain = Nothing End Sub Private Sub cmdRead_Click() Dim bytInput() As Byte Dim bytElement As Byte Dim iX As Long Dim iY As Long Dim iL As Long Dim iP As Long Dim sResult As String Dim sHistory As String Dim sData As String Dim sSpace As String On Error GoTo ErrTrap If comSerial.PortOpen = False Then comSerial.PortOpen = True End If bytInput = comSerial.Input iX = UBound(bytInput(), 1) For iY = 0 To iX If sResult <> "" Then If iY Mod 4 Then sResult = " " & sResult Else sResult = vbCrLf & sResult End If End If bytElement = bytInput(iY) sData = Chr$(bytElement) For iL = 1 To 8 Select Case iL Case 4 sSpace = " , " Case Else sSpace = "" End Select sResult = sSpace & Abs(CInt(BitOn(CLng(bytElement), iL))) & sResult Next If sResult <> "" Then If Asc(sData) = 0 Then sData = "~" End If sResult = "(" & sData & ")> " & sResult End If Next txtRead.Text = sResult & vbCrLf cmdRead.Enabled = False lstHistory.AddItem ("Read " & sDataBits & " Bits" & " As " & sMode) Do While Len(sResult)

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iP = InStrRev(sResult, "(", , vbBinaryCompare) sHistory = Replace(Trim(Mid$(sResult, iP)), vbCrLf, "", , , vbBinaryCompare) sResult = Left(sResult, (iP - 1)) lstHistory.AddItem (sHistory & " :ASCII " & CStr(Asc(Mid$(sHistory, 2, 1)))) Loop txtSend.SetFocus txtSend.SelStart = 0 txtSend.SelLength = Len(txtSend.Text) cmdClearHistory.Enabled = True Exit Sub ErrTrap: MsgBox Err.Number & " " & Err.Description & vbCr & " Error Generated By " & Err.Source, vbCritical, _ "System Error Trap !" End Sub Private Sub cmdSend_Click() On Error GoTo ErrTrap If comSerial.PortOpen = False Then comSerial.PortOpen = True End If comSerial.Output = txtSend.Text cmdRead.Enabled = True lstHistory.AddItem ("Send " & sDataBits & " Bits" & " As " & sMode) lstHistory.AddItem txtSend.Text Exit Sub ErrTrap: MsgBox Err.Number & " " & Err.Description & vbCr & " Error Generated By " & Err.Source, vbCritical, _ "System Error Trap !" End Sub Private Sub Form_Load() Dim iX As Long Dim iY As Long Dim sTmp As String Dim sPort As String Dim sSelectedPort As String Dim bFlag As Boolean Dim opt As OptionButton VerifyPorts VerifySettings sSettings = comSerial.Settings sSelectedPort = comSerial.CommPort Select Case comSerial.InputMode Case comInputModeBinary optBinary.Value = True sMode = "Binary" Case comInputModeText optString.Value = True sMode = "String" End Select For iX = 0 To UBound(BaudRate()) cmbBaudRate.AddItem BaudRate(iX) Next sTmp = Left$(sSettings, (InStr(1, sSettings, ",", vbBinaryCompare) - 1)) sDataBits = Left$(Right$(sSettings, 3), 1) optDataBits(CInt(sDataBits)).Value = True

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cmbBaudRate.Text = sTmp iY = UBound(Ports) For iX = 0 To iY sPort = Ports(iX) optPort(iX).Visible = True optPort(iX).Caption = sPort If sPort = sSelectedPort Then bFlag = True optPort(iX).Value = True End If Next If Not bFlag Then comSerial.CommPort = CInt(optPort(0).Caption) optPort(0).Value = True End If bLoaded = True End Sub Private Sub optBinary_Click() If bLoaded Then comSerial.InputMode = comInputModeBinary sMode = "Binary" End If End Sub Private Sub optDataBits_Click(Index As Integer) Dim sTmp As String On Error GoTo ErrTrap If bLoaded Then sTmp = comSerial.Settings Mid(sTmp, (Len(sTmp) - 2), 1) = CStr(Index) sDataBits = CStr(Index) comSerial.Settings = sTmp UpdateSettings End If Exit Sub ErrTrap: MsgBox Err.Number & " " & Err.Description & vbCr & " Error Generated By " & Err.Source, vbCritical, _ "System Error Trap !" End Sub Private Sub optPort_Click(Index As Integer) If bLoaded Then comSerial.CommPort = CInt(optPort(Index).Caption) UpdateSettings End If End Sub Private Sub optString_Click() If bLoaded Then comSerial.InputMode = comInputModeText sMode = "String" End If End Sub Private Sub txtSend_Change()

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If txtSend.Text <> "" Then cmdSend.Enabled = True Else cmdSend.Enabled = False End If End Sub Private Sub cmdClearHistory_Click() lstHistory.Clear cmdClearHistory.Enabled = False End Sub Private Sub txtSend_GotFocus() txtSend.SelStart = 0 txtSend.SelLength = Len(txtSend.Text) End Sub Private Sub VerifySettings() Attribute VerifySettings.VB_Description = "Checks the registry for the last com port settings" Dim disposition As Long Dim sTmp As String On Error GoTo ErrTrap sSettings = comSerial.Settings sPortNum = comSerial.CommPort sSubKey = "Software\Damage Inc\Com Settings" If RegOpenKeyEx(lMainKey, sSubKey, 0, KEY_READ, hnd) Then If RegCreateKeyEx(lMainKey, sSubKey, 0, 0, 0, 0, 0, hnd, disposition) Then Err.Raise 1001, "VerifySettings() Sub", "Could Not Create Registry Key" End If End If sKeyValue = Space$(lLength) If RegQueryValueEx(hnd, sSettingsKey, 0, REG_SZ, ByVal sKeyValue, lLength) Then If RegOpenKeyEx(lMainKey, sSubKey, 0, KEY_WRITE, hnd) Then Err.Raise 1001, "VerifySettings() Sub", "Could Not Open Registry Key" Else If RegSetValueEx(hnd, sSettingsKey, 0, REG_SZ, ByVal sSettings, Len(sSettings)) Then Err.Raise 1001, "VerifySettings() Sub", "Could Not Set Registry Key Settings Value" End If End If Else comSerial.Settings = sKeyValue End If sKeyValue = Space$(lLength) If RegQueryValueEx(hnd, sPortKey, 0, REG_SZ, ByVal sKeyValue, lLength) Then If RegOpenKeyEx(lMainKey, sSubKey, 0, KEY_WRITE, hnd) Then Err.Raise 1001, "VerifySettings() Sub", "Could Not Open Registry Key" Else

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If RegSetValueEx(hnd, sPortKey, 0, REG_SZ, ByVal sPortNum, Len(sPortNum)) Then Err.Raise 1001, "VerifySettings() Sub", "Could Not Set Registry Key Port Value" End If End If Else comSerial.CommPort = sKeyValue End If RegCloseKey hnd Exit Sub ErrTrap: MsgBox Err.Number & " " & Err.Description & vbCr & " Error Generated By " & Err.Source, vbCritical, _ "System Error Trap !" End Sub Private Sub UpdateSettings() Attribute UpdateSettings.VB_Description = "Updates the registry entry to the current com port settings" On Error GoTo ErrTrap sSettings = comSerial.Settings sPortNum = comSerial.CommPort sSubKey = "Software\Damage Inc\Com Settings" If RegOpenKeyEx(lMainKey, sSubKey, 0, KEY_WRITE, hnd) Then Err.Raise 1001, "VerifySettings() Sub", "Could Not Open Registry Key" Else If RegSetValueEx(hnd, sSettingsKey, 0, REG_SZ, ByVal sSettings, Len(sSettings)) Then Err.Raise 1001, "VerifySettings() Sub", "Could Not Set Registry Key Settings Value" End If End If If RegOpenKeyEx(lMainKey, sSubKey, 0, KEY_WRITE, hnd) Then Err.Raise 1001, "VerifySettings() Sub", "Could Not Open Registry Key" Else If RegSetValueEx(hnd, sPortKey, 0, REG_SZ, ByVal sPortNum, Len(sPortNum)) Then Err.Raise 1001, "VerifySettings() Sub", "Could Not Set Registry Key Port Value" End If End If Exit Sub ErrTrap: MsgBox Err.Number & " " & Err.Description & vbCr & " Error Generated By " & Err.Source, vbCritical, _ "System Error Trap !" End Sub Public Function BinaryToDecimal(Binary As String) As Long Dim n As Long Dim s As Integer

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For s = 1 To Len(Binary) n = n + (Mid(Binary, Len(Binary) - s + 1, 1) * (2 ^ (s - 1))) Next s BinaryToDecimal = n End Function Sub Pause(seconds As Integer) Const SECS_INDAY = 24! * 60 * 60 ' Seconds per day Dim start As Single start = Timer Do: Loop Until (Timer + SECS_INDAY - start) Mod SECS_INDAY >= seconds End Sub Module1.bas ‘For logging and mapping Attribute VB_Name = "Module1" 'These are the API functions that makes it all possible (to use BitBlt and other functions) Public Declare Function BitBlt Lib "gdi32" (ByVal hDestDC As Long, ByVal X As Long, ByVal Y As Long, ByVal nWidth As Long, ByVal nHeight As Long, ByVal hSrcDC As Long, ByVal xSrc As Long, ByVal ySrc As Long, ByVal dwRop As Long) As Long Public Const SRCAND = &H8800C6 Public Const SRCCOPY = &HCC0020 Public Const SRCERASE = &H4400328 Public Const SRCINVERT = &H660046 Public Const SRCPAINT = &HEE0086 Public Declare Sub Sleep Lib "kernel32" (ByVal dwMilliseconds As Long) Sub SetLog(Message As String) Dim theFile As String, theMessage As String theFile = App.Path & "\data.txt" theMessage = Message & vbCrLf Open theFile For Append As #1 Print #1, theMessage Close #1 End Sub Sub KillLog() On Error Resume Next Kill App.Path & "\data.txt" On Error GoTo 0 End Sub RegistryAPIs.bas ‘Look for available serial ports. Attribute VB_Name = "RegistryAPIs" Option Explicit '----------------------------------------------------------------------------------------------------------------------- Public Const SYNCHRONIZE = &H100000

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Public Const READ_CONTROL = &H20000 Public Const STANDARD_RIGHTS_READ = (READ_CONTROL) Public Const STANDARD_RIGHTS_WRITE = (READ_CONTROL) Public Const STANDARD_RIGHTS_ALL = &H1F0000 '----------------------------------------------------------------------------------------------------------------------- Public Const KEY_QUERY_VALUE = &H1 Public Const KEY_ENUMERATE_SUB_KEYS = &H8 Public Const KEY_NOTIFY = &H10 Public Const KEY_SET_VALUE = &H2 Public Const KEY_CREATE_SUB_KEY = &H4 Public Const KEY_READ = ((READ_CONTROL Or KEY_QUERY_VALUE Or KEY_ENUMERATE_SUB_KEYS Or KEY_NOTIFY) And (Not SYNCHRONIZE)) Public Const KEY_WRITE = ((STANDARD_RIGHTS_WRITE Or KEY_SET_VALUE Or KEY_CREATE_SUB_KEY) And (Not SYNCHRONIZE)) '----------------------------------------------------------------------------------------------------------------------- Public Const ERROR_SUCCESS = 0& '----------------------------------------------------------------------------------------------------------------------- Public Const REG_SZ = 1 Public Const REG_BINARY = 3 Public Const REG_DWORD = 4 '----------------------------------------------------------------------------------------------------------------------- Public Const HKEY_CLASSES_ROOT = &H80000000 Public Const HKEY_CURRENT_USER = &H80000001 Public Const HKEY_LOCAL_MACHINE = &H80000002 Public Const HKEY_USERS = &H80000003 Public Const HKEY_PERFORMANCE_DATA = &H80000004 Public Const HKEY_CURRENT_CONFIG = &H80000005 Public Const HKEY_DYN_DATA = &H80000006 '----------------------------------------------------------------------------------------------------------------------- Public Const REG_CREATED_NEW_KEY = &H1 Public Const REG_OPENED_EXISTING_KEY = &H2 Public Declare Sub Sleep Lib "kernel32" (ByVal dwMilliseconds As Long) '----------------------------------------------------------------------------------------------------------------------- Public Declare Function SleepEx Lib "kernel32" (ByVal dwMilliseconds As Long, ByVal bAlertable As Long) As Long '----------------------------------------------------------------------------------------------------------------------- Public Declare Function RegOpenKeyEx Lib "advapi32.dll" Alias "RegOpenKeyExA" (ByVal hKey As Long, ByVal lpSubKey As _ String, ByVal ulOptions As Long, ByVal samDesired As Long, phkResult As Long) As Long '----------------------------------------------------------------------------------------------------------------------- Public Declare Function RegCloseKey Lib "advapi32.dll" (ByVal hKey As Long) As Long '----------------------------------------------------------------------------------------------------------------------- Public Declare Function RegQueryValueEx Lib "advapi32.dll" Alias "RegQueryValueExA" (ByVal hKey As Long, ByVal _ lpValueName As String, ByVal lpReserved As Long, lpType As Long, lpData As Any, lpcbData As Long) As Long '----------------------------------------------------------------------------------------------------------------------- Public Declare Function RegCreateKeyEx Lib "advapi32.dll" Alias "RegCreateKeyExA" (ByVal hKey As Long, ByVal lpSubKey _

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As String, ByVal Reserved As Long, ByVal lpClass As Long, ByVal dwOptions As Long, ByVal samDesired As Long, ByVal _ lpSecurityAttributes As Long, phkResult As Long, lpdwDisposition As Long) As Long '----------------------------------------------------------------------------------------------------------------------- Public Declare Function RegDeleteKey Lib "advapi32.dll" Alias "RegDeleteKeyA" (ByVal hKey As Long, ByVal lpSubKey As _ String) As Long '----------------------------------------------------------------------------------------------------------------------- Public Declare Function RegSetValueEx Lib "advapi32.dll" Alias "RegSetValueExA" (ByVal hKey As Long, ByVal _ lpValueName As String, ByVal Reserved As Long, ByVal dwType As Long, lpData As Any, ByVal cbData As Long) As Long '----------------------------------------------------------------------------------------------------------------------- Public Declare Function RegEnumKey Lib "advapi32.dll" Alias "RegEnumKeyA" (ByVal hKey As Long, ByVal dwIndex As Long, _ ByVal lpName As String, ByVal cbName As Long) As Long '----------------------------------------------------------------------------------------------------------------------- Public Declare Function RegDeleteValue Lib "advapi32.dll" Alias "RegDeleteValueA" (ByVal hKey As Long, ByVal _ lpValueName As String) As Long '----------------------------------------------------------------------------------------------------------------------- Public Declare Function RegEnumValue Lib "advapi32.dll" Alias "RegEnumValueA" (ByVal hKey As Long, ByVal dwIndex As _ Long, ByVal lpValueName As String, lpcbValueName As Long, ByVal lpReserved As Long, lpType As Long, lpData As Any, _ lpcbData As Long) As Long '----------------------------------------------------------------------------------------------------------------------- Public Declare Sub CopyMemory Lib "kernel32" Alias "RtlMoveMemory" (dest As Any, Source As Any, ByVal numBytes As Long) '----------------------------------------------------------------------------------------------------------------------- Declare Function FormatMessage Lib "kernel32" Alias "FormatMessageA" (ByVal dwFlags As Long, lpSource As Any, ByVal _ dwMessageId As Long, ByVal dwLanguageId As Long, ByVal lpBuffer As String, ByVal nSize As Long, Arguments As Long) _ As Long '----------------------------------------------------------------------------------------------------------------------- Public Declare Sub keybd_event Lib "user32" (ByVal bVk As Byte, ByVal bScan As Byte, ByVal dwFlags As Long, _ ByVal dwExtraInfo As Long) Public Const VK_CONTROL = &H11 Public Const VK_C = &H43 Public Const VK_V = &H56 Public Const KEYEVENTF_KEYUP = &H2 '----------------------------------------------------------------------------------------------------------------------- Type OSVERSIONINFO dwOSVersionInfoSize As Long dwMajorVersion As Long dwMinorVersion As Long dwBuildNumber As Long dwPlatformId As Long

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szCSDVersion As String * 128 End Type '----------------------------------------------------------------------------------------------------------------------- Public Const VER_PLATFORM_WIN32_NT = 2 Public Const VER_PLATFORM_WIN32_WINDOWS = 1 Public Const VER_PLATFORM_WIN32s = 0 Public Declare Function GetVersionEx Lib "kernel32" Alias "GetVersionExA" (lpVersionInformation As OSVERSIONINFO) As _ Long '----------------------------------------------------------------------------------------------------------------

VIII. APPENDIX C: REFERENCES About Ultrasonic Sensors:

1. www.robot-electronics.co.uk 2. www.acroname.com/robotics/parts/R93-SRF04.html 3. http://www.uoxray.uoregon.edu/polamod/ 4. http://www.pioneernet.net/johnc/als5ears.htm 5. http://www.tntech.edu/me/courses/Canfield/me4370/6500.htm 6. http://www.engr.udayton.edu/faculty/jloomis/ece445/topics/sonar/faq.html 7. https://www.zagrosrobotics.com/sonar.htm 8. http://www.robofolio.com/folio/sonar/ 9. http://www.arches.uga.edu/~dass/srf04.html 10. http://www.kronosrobotics.com/an149/DAN149.htm 11. http://www.rentron.com/remote_control/SRF04.htm 12. http://www.junun.org/MarkIII/Info.jsp?item=23 About PIC Microcontroller:

1. www.microchip.com 2. http://controls.ae.gatech.edu/gtar/electronics/ 3. http://www.mstracey.btinternet.co.uk/pictutorial/ 4. http://www.ic-prog.com/ 5. http://www.embedded.com/1999/9904/9904feat2.htm 6. http://www.picallw.com/ About Serial Communication:

1. http://ohm.bu.edu/edf/info/serial_pinout.html 2. http://www.lookrs232.com/rs232/history_rs232.htm 3. http://vacuumfeedthru.com/tech_libr/rs-232-c.htm 4. http://www.piclist.com/techref/microchip/16F877/rs232-cr.htm 5. http://home.earthlink.net/~botronics/index/pickey.html

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IX. APPENDIX D: COST In all engineering projects one of the important criteria is the cost of project. We also show our budget.

PART COST ( TL )

3 * SRF04 sensors 147.500.000 TL

1* PIC 16f877 micocontroller 8.000.000 TL

Electronic Components( Max232 IC, 7805 Voltage Regulator, XT, Capacitors,Resistors) 6.000.000 TL

PIC 16F877 JMD Programmer 35.000.000 TL TOTAL 196.000.000 TL