RobocupVision

From GT RoboJackets

Contents 1 What We Need Now 2 Calculations 2.1 Data 2.2 Results 2.2.1 One Camera 2.2.2 Two Cameras 2.2.3 Speed

What We Need Now

• Images of the field with robots on it from the perspective of the camera. Video would be nice.

Calculations

Data

• The field is roughly 5 x 3.5 m
• The ball is .043 m in diamater
• The equipment bar is 4 m above the field
• Each pixel is 8 bits

Results

One Camera

• With VGA resolouton (640 x 480) there are roughly 1.28 pixels/cm.
• There are roughly 23.7 pixels in a ball (the smallest item on the field - bar the lines).
• The lens needs a 64 degree field of view (simple trig) tan(theta/2) = FOV/(2xWD)
• With a 60 FPS camera, we would need to process 137 MB of image data faster then every second
• With a 100 FPS camera, we would need to process 227MB of image data faster then every second

Two Cameras

• With VGA rsoloution (640 x 480) there are roughly 1.8 pixels/cm.
• Meaning roughly 37 pixels in a ball
• Lens would need 35 degree field of view
• With a 60 FPS camera, we would need to process 274 MB of image data faster then every second
• With a 100 FPS camera, we would need to process 454 MB of image data faster then every second

Speed

• If the ball moves at 2.5 feet/sec (1.7 mi/hr) with a 30 fps camera, there will be a frame for every inch the ball moves
• If the ball moves at 2.5 feet/sec (1.7 mi/hr) with a 60 fps camera, there will be two frames for every inch the ball moves
• If the ball moves at 2.5 feet/sec (1.7 mi/hr) with a 100 fps camera, there will be 3.33 frames for every inch the ball moves
• If the ball moves at 8.33 feet/sec (5.66 mi/hr) with a 100 fps camera, there will be a frame for every inch the ball moves
• If the ball moves at 16.66 feet/sec (11.22 mi/hr) with a 100 fps camera, there will be a frame for every two inches the ball moves