INTRODUCTION

The goal of the Carnegie Mellon's CMUcam project is to provide simple vision capabilities to small-embedded systems in the form of an intelligent sensor. The CMUcam open source programmable embedded color vision sensors are low-cost, low-power sensors for mobile robots. You can use the CMUcam vision systems to do many different kinds of on-board, real-time vision processing tasks. The CMUcam4 is a fully programmable embedded computer vision sensor. The main processor is the Parallax P8X32A (Propeller Chip) connected to an OmniVision 9665 CMOS camera sensor module.  

The CMUcam4 can be used to track colors or collect basic image statistics. The best performance can be achieved when there are highly contrasting and intense colors. For instance, it can easily track a red ball on a white background, but it would be hard to differentiate between different shades of brown in changing light. Tracking colorful objects can be used to localize landmark, follow lines, or chase moving beacons. Using color statistics, it is possible for the CMUcam4 to monitor a scence, detect a specific color, or do primitive motion detection. If the CMUcam4 detects a drastic color change, then chances are something in the scene changed. Using "Line Mode", the CMUcam4 can generate low resolution binary images of colorful objects. This can be used to do more sophiscated image processing that includes line following with branch detection, or even simple shape recognition. These more advanced operations require custom algorithms to post process the binary iages sent from the CMUcam4. As is the case with a normal digital camera, this type of processing might require a computer or at least a fast microcontroller.

SPECIFICATION

·         Fully open source and re-programmable using the Propeller Tool

·         Arduino Shield Compatible w/ Supporting Interface Libraries and Demo Applications for the Arduino and BASIC Stamp

·         VGA resolution (640x480) RGB565/YUV655 color sensor

·         Image processing rate of 30 frames per second

·         Raw image dumps over serial or to flash card

·         (640:320:160:80)x(480:240:120:60) image resolution

·         RGB565/YUV655 color space

·         Onboard Image Processing (QQVGA 160x120)

·         Track user defined color blobs in the RGB/YUV color space

·         Mean, median, mode and standard deviation data collection – sampled from a 40x120 resolution

·         Segmented (thresholded) image capture for tracking visualization (over serial or to flash card)

·         80x60 image resolution

·         Monochrome color space

·         Histogram generation (up to 128 Bins) – sampled from a 40x120 resolution

·         Arbitrary image clipping (windowing)

·         μSD/μSDHC flash card slot with FAT16/32 full file system driver support w/ Directory and File manipulation

·         I/O Interfaces

·         Two-port servo controller (pan and tilt w/ 1us resolution at a 50 Hz refresh rate)

·         Pan and/or Tilt servo channels can be configured as GPIOs

·         Indicator user controllable LED (red) and power LED (green)

·         TTL UART (up to 250,000 baud – 19,200 baud by default)

·         Monochrome baseband analog video output (NTSC/PAL) of 160x120 resolution for tracking visualization (segmented (thresholded) image w/ color centroid and bounding box overlay at 30 FPS)

·         CMUcam4 GUI for viewing images on the PC

DOCUMENTS

·         CMUcam4 Project Home

·         How to use the CMucam4 properly on Youtube

·         CMUcam4 Guide                                  

·         CMUcam4-Arduino-Interface-Library          

·         CMUcam4-Board Layout and Ports             

·         CMUcam4-SCH                                   

·         Color Tracking Car Using CMUcam4             

·         Demo Mode of CMUcam4