1. Steve Andre Eric Glover Shaun Greene Russell Willmot

2. An ability to: 1. display a pattern with rotating LEDs 2. control the direction in which the pattern is being projected 3. track the angle of arrival of an RF beacon 4. update a projected image while the machine is in operation 5. accept user-generated input to change display

3. March 3, 1983 1200-1800 RPM On-board microprocessor 3 LED bars Zero-position sensor Measures speed All components rotate

4. October 15, 1991 Stationary & rotary components Power transfer using slip rings 16 LED bars No microcontroller! Data transfer through rotary transformer Precise motor speed control Removable data socket

5. December 27, 1994 Hand-held wand (waved back and forth to create image) Does not require uniform rotary motion Single bar of LEDs Switch to determine beginning of new cycle

6.  1800 RPM (but does not require precise motor speed control)  Stationary & rotary components  Data transfer through wireless transceiver  Two microprocessors  Can update while in operation  Displays in user-determined direction  Displays user-generated text or images  Power transfer through slip rings  Zero-position sensor