Hello everybody !!! :)
The main aim of this project is to convert a normal computer monitor into a touch screen monitor.. For this I use 2 SRF005 ultrasonic range sensors and 1 picaxe 28X2.
The above image is the baisc plan of my project and it will explain you how things work.
I use VB.NET to interface between the Picaxe and the computer.
My picaxe code is :
#picaxe 28x2
main:
pulsout C.1,2
pulsin C.1,1,w1
pause 10
let w1 = w1 * 10/62
pulsout C.2,2
pulsin C.2,1,w2
pause 10
let w2 = w2 * 10/62
sertxd (w1," ",w2)
and my VB code is :
Imports System.IO
Imports Strings = Microsoft.VisualBasic
Imports System.Math
Public Class Form1
Public Declare Auto Function GetCursorPos Lib "User32.dll" (ByRef lpPoint As Point) As Long
Public Const MOUSEEVENTF_LEFTDOWN = &H2
Public Const MOUSEEVENTF_LEFTUP = &H4
Private Const MOUSEEVENTF_RIGHTDOWN = &H8
Private Const MOUSEEVENTF_RIGHTUP = &H10
Public Const MOUSEEVENTF_MIDDLEDOWN = &H20 ' middle button down
Public Const MOUSEEVENTF_MIDDLEUP = &H40 ' middle button up
Declare Function apimouse_event Lib "user32.dll" Alias "mouse_event" (ByVal dwFlags As Int32, ByVal dX As Int32, ByVal dY As Int32, ByVal cButtons As Int32, ByVal dwExtraInfo As Int32) As Boolean
Public Declare Sub Sleep Lib "kernel32" (ByVal dwMilliseconds As Integer)
Dim WithEvents serialPort As New IO.Ports.SerialPort
Dim PicaxeRegisters(0 To 2) As Byte
Dim w1 As Integer
Dim i As Integer
Dim var As Integer
Dim w2 As Integer
Private Sub Form1_Load(ByVal sender As Object, ByVal e As System.EventArgs) Handles Me.Load
Timer1.Enabled = True
Timer1.Interval = 1000 ' the interval at which the serial port accepts the data & this can be varied
End Sub
Private Sub Timer1_Tick(ByVal sender As System.Object, ByVal e As System.EventArgs) Handles Timer1.Tick
Call SerialTxRx()
End Sub
Sub SerialTxRx()
Dim labelstring As String
Dim labelstring1 As String
If serialPort.IsOpen Then
serialPort.Close()
End If
Try
With serialPort
.PortName = "COM1"
.BaudRate = 9600
.Parity = IO.Ports.Parity.None
.DataBits = 8 ' 8 bits
.StopBits = IO.Ports.StopBits.One
.Open()
.DiscardInBuffer()
Call Sleep(100)
.Read(PicaxeRegisters, 0, 3) ' the 3 is because of the 2 values of the SRF005 + 1 space between the two values
.Close()
End With
Label1.Text = PicaxeRegisters(0)
Label2.Text = PicaxeRegisters(2)
labelstring = PicaxeRegisters(0)
labelstring1 = PicaxeRegisters(2)
If PicaxeRegisters(2) < 116 And PicaxeRegisters(0) < 123 And PicaxeRegisters(0) > 2 And PicaxeRegisters(2) > 2 Then ' limits
Dim x As Double
Dim y As Double
If PicaxeRegisters(2) > 30 Then
x = (112 - labelstring1) * 18 ' 112 is the extreme value of x & it depends on your monitor
y = (120 - labelstring) * 18 '120 is the maximum value of y
'18 used to convert the SRF005 value's unit to pixel. My
y = 900 - y ' 900 is the maximum pixel value(because my monitor is a 1440 X 900 monitor
Me.Cursor = New Cursor(Cursor.Current.Handle)
If x > 700 Then
x = x + (x - 700) * 0.25 'to maximise accuracy, increase or decrease 0.25 according to your convinience
End If
Cursor.Position = New Point(x, y)
Else
Call apimouse_event(MOUSEEVENTF_LEFTDOWN, 0, 0, 0, 0)
End If
Label3.Text = x
Label4.Text = y
Else
Call apimouse_event(MOUSEEVENTF_LEFTUP, 0, 0, 0, 0)
End If
Catch ex As Exception
MsgBox(ex.ToString)
Label1.Text = "Timeout"
End Try
End Sub
End Class
What this does is : The two SRF05 sensors send the distance values (horizontal and vertical) to the COM port, which is recieved by the VB code and it makes some calculations as shown above to move the cursor to the position where you pointed to.
You can also use " Call apimouse_event(MOUSEEVENTF_MIDDLEUP, 0, 0, 0, 0)" and " Call apimouse_event(MOUSEEVENTF_MIDDLEDOWN, 0, 0, 0, 0)" to deal with scrolling
This project is not very tough to make, but it takes a lot of time and patience to do it... Please give me some suggestions and improvements(if any) as comments.
Thank You
Takes the mouse pointer to the position where we point depending on the distance given by the two SRF05
- CPU: PICAXE 28X2
- Operating system: Windows 7
- Power source: 9V (with 5V regulator)
- Programming language: Picaxe basic
- Sensors / input devices: SRF05 Ultra Sound
- Target environment: indoor
This is a companion discussion topic for the original entry at https://community.robotshop.com/robots/show/touch-screen-monitor
