A place to keep notes about construction issues and solutions
What ball to use?
How to track motion of ball?
'Optical flow sensor module' (extended version of optical mouse adapted for use for drone stabilization)
ADNS-3080 Optical Flow Sensor Module - Plays well with arduino, older technology (30x30pix, 2000+ frames/sec, $22.50/pc) Example
YouTube demo of how it works and associated code on github
PMW3901 Optical Flow Sensor - integrated into the PIM453 module (alternate source) that plays well with Rasberry PI.
Multiple can be interfacted to a single Raspberry Pi through this breakout board
More elaborate system-on-a-chip optimized for visual flow, designed for dones: PX4FLOW smart cameraÂ
FicTrac - webcam based method
Main project page ** THIS SEEMS THE MOST PROMISING **