CMUcam

1
CMUcam

• for
• µCHIP
• (Micro-Controlled High-tech Independent Putter)

2
What is the CMUcam?

• OV6620 Omnivision CMOS camera
• SX28 microcontroller for image processing
• 80 x 140 resolution
• Track colors based on RGB values
• Provide position and size of color object
• PC java interface for testing

3
Microcontroller Interface

• Transmit/receive data via USART _at_ TTL levels
• Use Raw serial transfer mode
• Process incoming stream and parse relevant data
  into variable arrays
• Use dynamic averaging to filter and reduce jitter

4
Implementation

• Use TW (track color in window) command to
  calibrate determine the color of the ball and the
  hole marker at startup
• Store RGB values in memory
• Use TC (track color) to find ball and hole marker
• Easiest color to detect Red

5
Ball Detection

• Use servo to aim camera down to limit vision
• Follow ball with camera on approach
• Use middle-of-mass values (x y) to center robot
  over the ball for putting
• Probably use bright LEDs to control lighting for
  positioning

6
Hole Detection

• Aim camera forward and spin around ball
• Use middle of mass x value to determine direction
• Use middle of mass y value to filter other
  objects
• Use of pixels in tracked region to determine
  distance
• Reliable tracking up to 6 feet