Picking up table tennis balls after practice is what I dread the most. I also appreciate the importance of a dust free environment for the problem free operation of my Newgy Robot. I have found that by pushing the balls with an electrostatic dry sweeper (SwifferTM, Grab-ItTM, PledgeTM), I can get most of the balls to a corner where I can easily pick them all at once. Meanwhile, the electrostatic dry sweeper is getting rid of the dust!
A clean practice area is crucial for the robot as well as the person practicing (s/he is eventually breathing all that dust) and the easier it is to collect the balls, the more I enjoy my practice.
(Editor's Note: Sarkis is right, dust is a frequent problem for all Newgy robots. Dust typically enters the machine by clinging to the balls and then falling off the balls as they are pushed through the robot. Dust can accumulate on the rubber surfaces of the Discharge Wheel and Friction Block, causing erratic delivery and lack of spin. Dust can clog gears and I've even seen cases where dust has literally "strangled" a motor's drive pin, preventing it from turning. Use Sarkis' tip to prevent dust from entering your machine and your robot will last longer and give you more trouble-free service..)