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DIY Camera for Pick & Place the easy way ..
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Please be positive and constructive with your questions and comments.

DIY Camera for Pick & Place the easy way ..

by alphatronique on Wed Oct 23, 2013 10:33 am

Hi

few year back when i playing to make my own pick place i got idea to use
Barcode scanner as vision system ,and never got opportunity to try this

since i just buy a lot of barcode reader and 1 have broke handle it time to play :mrgreen:

so it use nice linear CCD whit 3648 pixel all that fit on a box whit optic in place
put 5 volt supply and internal pcb start scan the sensor ,just need to tap into desired signal

http://www.oceanoptics.com/technical/de ... 1304ap.pdf

we need "shift gate" , clock ,"analog out" signal for make thing easy analog was route to a voltage comparator and feed into a interrupt pin of a ardunino or similar same for shift gate and clock .. ( i let you do code part since i now own 2 MyData pick place so DIY project was dead)

"shift gate" pin was trigger for start a counter and take clock as clock source
then you use comparator out to latch counter value for raise and falling edge of signal
raising edge was part start and falling was part end , counter value between the 2 edge will tell you part dimension and value from start the distance from pixel 0

so on machine setup you need to find nozzle position (clock cont) then whit bit of math
you able to got if measured part position from nozzle position ...

since i knot that i not clear sometime since english was not my first language
let see image ... http://youtu.be/fFdDQuVusrw

white trace = analog out , green trace = "shift gate" and yellow = clock
when i put the 30awg wire you see wire position and pulse width = wire width
and if it see a 30awg wire it will see any part whit no issue :mrgreen:
feild of view was bit under a inch so in theory you may resolve 1/3648 of a inch :shock:

ok so i let you complete that project .. some minor note i found useful ..
1-) for work need a white back ground since no back ground = like it see black and part are black

2-) background need to be a 45 deg angle , if not CCD will see part shadow on the background

3-)barcode i use was IT3800 CCD barcode scanner it come in ton of clone model to ..

p.s. if some one was ambitious it may also use a bottom vision and use X or Y for simulate more CCD line by swipe part over the sensor just like MyData line scan camera but that need opti swap ...
Attachments
ccd2.jpg
optical block detail
ccd2.jpg (53.45 KiB) Viewed 1895 times
ccd.jpg
CCD module and setup ...
ccd.jpg (60.77 KiB) Viewed 1899 times
Best regard
Marc Lalonde CID.
IPC Certified PCB Designer.
Alphatroniqe inc.
www.alphatronique.com
http://ca.groups.yahoo.com/group/MyData_Group

alphatronique
 
Posts: 231
Joined: Fri Jun 25, 2010 8:30 am

Re: DIY Camera for Pick & Place the easy way ..

by alphatronique on Wed Oct 23, 2013 2:57 pm

Hi

Have play a bit more ,initially i expected that analog signal was send through a ADC
to a DSP for decoding the barcode .

but got surprise to find that it actually make most of the job for us
it filter signal ,do automatic gain control and turn it into 3.3V TTL signal pulse
so mo need of voltage comparator and seting it all was done by itself :mrgreen:

just need to hook into the right test point , please refer to this image for the Test point

and i include image of a real bar-code and one of the same 30awg wire

so just need to hood to a CPU and write some code
Attachments
TEK00000.jpg
30 awg see from Test Point
TEK00000.jpg (110.43 KiB) Viewed 1889 times
TEK00001.jpg
real barcode see from the TP
TEK00001.jpg (86.7 KiB) Viewed 1889 times
ccd3.jpg
Test point location
ccd3.jpg (249.46 KiB) Viewed 1889 times
Best regard
Marc Lalonde CID.
IPC Certified PCB Designer.
Alphatroniqe inc.
www.alphatronique.com
http://ca.groups.yahoo.com/group/MyData_Group

alphatronique
 
Posts: 231
Joined: Fri Jun 25, 2010 8:30 am

Please be positive and constructive with your questions and comments.