Version 3 (Kwabena Agyeman, 02/12/2012 11:58 pm)

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h1. Frequently Asked Questions
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h2. *General Questions*
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h3. *What is unique about CMUcam1?*
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Traditionally fast computers are needed to capture and process camera images. It is also necessary to write the software to perform this processing. Because of this it is difficult to use vision as a sensor in simple systems.  
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The CMUcam1 vision system uses a fast low cost microcontroller to handle all of the high speed processing of the camera data and contains software to perform simple vision tasks. Because the user can choose to output only low bandwidth high level information from the vision system, like the red object is at position X-Y, it is possible for a simple processor like a PIC Microcontroller to read this data and direct a small robot in tasks like chasing a colored ball. The CMUcam1 vision system makes it possible to ignore the complexity of camera interfacing and use vision just like any other sensor (i.e. sonar) often used in robotic systems.  
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h3. *How much would it cost to build a complete CMUcam1?*
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The CMOS camera board costs $60. The CMUcam1 PCB board costs about $10. The cost of the components to stuff the board at unit cost is about $30. The total cost of a single vision system is about $100.
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h3. *What is CMUcam1's frame rate?*
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The fastest frame rate is 16.7 frames per second.  This means CMUcam1 can tell you the position of an object about 17 times per second. Using the serial software protocol you can slow this down if desired.
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h3. *What baud rates does the CMUcam1 support?*
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As of the latest version of the firmware (v1.12) the CMUcam1 can communicate at baud rates of 9600, 19200, 38400 or 115200. The baud rate is selected via jumper settings on the board.
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h3. *How do I upgrade my CMUcam1 firmware?*
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If you are currently using firmware v1.11 there is no reason to upgrade unless you need support for the lower baud rates. Version 1.11 supports 38400 and 115200 baud. Version 1.12 supports those baud rates and adds support for 9600 and 19200 baud. To upgrade your firmware you will need to reprogram the flash memory in your processor chip. The easiest way to upgrade is to purchase a new processor with the new code flashed into it. To do this contact the company you purchased your CMUcam1 from. If you have a programmer (which are expensive) you can download the current version from our [[downloads]] page and re-flash the processor yourself.
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h3. *Does CMUcam1 work outside?*
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The CMUcam1 works outside but not in direct sunshine. The CMOS camera we are using does not have a high-quality IR filter, and so sunlight saturates the red pixels and the image becomes, essentially, monochrome in direct sunlight. (It is possible to add an external filter to improve outdoor operation). We have a short write up in [[publications]] that shows you how illumination conditions affect CMUcam1.
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h3. *Can I write custom code for CMUcam1?*
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Certainly. To do this, ask us for the firmware source code, order yourself a C programming environment for the "Ubicom":http://www.ubicom.com chip and go for it.  When we send you the firmware source code we will also send you a summary of how the code is structured and information about the programming environment we use.
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h2. *Technical Questions*