Motion Tracking with the RCX and Quickcam

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Motion Tracking with theRCX and Quickcam

• Dan HuberJoe Winegarden

http//www4.ncsu.edu/jjwinega/csc714/ CSC 714
Final Project
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Motion Tracking Setup

• Quickcam mounted on top of motor, RCX brick sits
  to the side for less weight
• Quickcam connected to linux PC via USB
• PC runs lnpd to communicate with IR tower
• PC runs frame grabber code, sends messages
  through tower to RCX
• RCX waits for message received, rotates until
  told to do otherwise

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Image Processing

• Grab frames every 50 ms, determine where most
  blue pixel is located based on center of frame
• Messages are 0 (stop turning), 1 (rotate left), 2
  (rotate right)

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Issues Solved/Unsolved

• Improv image processing software difficult to
  adapt to our application, so we wrote all
  frame-grabbing and image processing code
  ourselves
• Video4Linux API for frame-grabbing code
• lnpd makes IR communication very simple
• Completely separate from BrickOS
• Just include library and call 'lnp_addressing_writ
  e()'
• Extremely stiff USB camera cable greatly
  restricts the rotational movement of the camera
• Can't follow blue pen more than a few degrees
  without requiring man-power to assist camera
  movement
• Reacts in real time!