According to Mashable, PoolLiveAid hangs above the pool table and analyzes the position of the ball and the angle in which the cue stick is held to predict where the shot will go. The projector then shines the predicted line onto the table. (See demonstration video below.)
Ricardo Alves and Luis Sousa, electronic engineering students at the university, designed the device as a final project for one of their classes.
"We developed an algorithm that tracks and analyzes the ball's position," Alves told Mashable. "It detects lines that match up with the cue. The computer's connected to the projector too, so it updates right away."
The students will present their design at the 21st International Conference on Computer Graphics, Visualization and Computer Vision 2013 in the Czech Republic next month.