a hexapod that sees

[benji]

HEllo folks , im new here,, lookslike its a nice place to talk robots,,, right
i want to make a hexapod that has object recognition.
so i want to implement a camera ,,i want to know what kind of camera is good for such a project
im new to robot vision so i need some help with this
i want to build this using the micro 8051 as long as i know to program it with assembly language.
i would appreciate any idea
thanks

[Steve Joblin]

Two suggestions:

1.  Check out the tutorial on Robotic vision at Society of Robots (http://www.societyofrobots.com/programming_computer_vision_tutorial.shtml)
2.  Check out RoboRealm (http://www.roborealm.com)

[benji]

well thanks for providing these links i actually did read em
but they dont actually explain much about interfacing the camera with the microcontroller
know any website does it?
or maybe can i use a webcam instead of a digital cam?

[Steve Joblin]

You don't attach a camera (or webcam) directly to a Microcontroller.  RoboRealm does the image processing on a PC.  Have you looked at the CMUcam?  The CMUcam has it's own processors that connect to a microcontroller.

[h3ro]

Have you looked at the CMUcam?  The CMUcam has it's own processors that connect to a microcontroller.

Sorry to pop in a noob question, but here it goes:
What kind of processing does the CMU camera do? Is all the image tracking/manipulation done for you (is it possible to modify/ change it?). What does the CMU output?

Edit:
Is it much harder to use a webcam over say CMU? I did a quick google, but could not find any specific info on how to use a webcam in a robot project (without using a pc)

[benji]

yea thats what im talking about, i want to make my imaghe processing program inside the micro controller
say like shape recognition, i dont want to use a pc
somthing like interfacing a cmos camera into a microcontroller without a pc.
the camera just outputs information and i process it by the 8051 microcontroller and give commands to the servos to drive the robot. thats what im talking about
if anyone has info please help .....

[paulstreats]

its really just a case of finding out how the camera outputs its data, and then interpreting it on the mcu.
The real problem is memory requirements. A 256*256 pixel image with just 256 colours will take 512kb or 65,536*8bits.
most cameras have their own processor on board which exports either YUV24 or RGB24 data, you should look at how to convert this stream data into virtual image data

[paulstreats]

after thinking a bit more, i know the 8051 range are expandable externally, you would probably be better with a high end atmel mcu such as this
http://www.atmel.com/dyn/products/tools_card.asp?tool_id=4114
http://www.atmel.com/dyn/products/tools_card.asp?tool_id=4175

these are evaluation boards with high end processors.

here is a link to a pdf which shows how to interface a cmucam1 to a pic16f877
http://www.mil.ufl.edu/imdl/papers/IMDL_Report_Fall_02/nagy_jeno/sensors.pdf

[dunk]

hi Benji,
have a look at the AVRcam to see how to go about interfacing a camera. it will give you some idea how much work is involved.
it's similar in concept to the CMUcam.
http://www.jrobot.net/Projects/AVRcam.html

dunk.

[benji]

well thank u people for the info but lookslike i want to build the CMUcam too, thats what i actually want
to interface the vision sensor to a ucontroler and in the same micro ill do some processing,
about the memory size im ok with a black and white camera with a small number of pixels cuz i dont want to complicate the program much cuz i program in assembly language.
is it that the OV6620 sensor is the most common?
ive heard also about the gameboy camera ,, anybody have comments about it? information about its output data and interfacing?

thnkyall

[airman00]

hacking gameboy camera - http://www.geocities.com/SiliconValley/Park/1302/gbcam.html

heres a robot that uses the whole darn gameboy!



search around on google and you'll find more info
http://www.streettech.com/modules.php?op=modload&name=News&file=article&sid=489&mode=thread&order=0&thold=0

[Admin]

For those you have never made a robot before, I just want to stress to back away from the cool stuff, and just work on the basics.

Save your computer vision for your next project, and first figure out how to interface a photoresistor (serious, even this requires quite a lot of learning).

As for the CMUcam questions, read the datasheet!

[benji]

here is a link that describes a little about how to interface photoresistors :

http://www.seattlerobotics.org/encoder/jun99/dusan.html

BUT,, i need vision (like object recognition). not light detection
anyways, what sensors are used for human following robots?

[Ro-Bot-X]

For following humans ar animals, you need a Passive Infra-Red (PIR) sensors. Acroname has it. Make sure to get a fresnel lens with it to increase range.

I am working on a robot that will use AVRcam to find objects based on the color of the object. I don't know that much programming to do object recognition. I will have a tutorial on this in February.

[benji]

well i would appreciate it if you can share this tutorial ,,i would be more than glad

actually i do program the 8051 family with assembly language
i have a little information of how to do blop detection

and thank you for the PIR hint

[h3ro]

here is a link that describes a little about how to interface photoresistors :

http://www.seattlerobotics.org/encoder/jun99/dusan.html

BUT,, i need vision (like object recognition). not light detection
anyways, what sensors are used for human following robots?

Looks interesting. Anyone here tried doing something like that?

How would it be to use a mobile phone camera like the ones you can buy at sparkfun?