ATLANTA — A fast-moving robot on wheels could one day challenge the best human tennis players at Wimbledon or the US Open — or replace them altogether! Scientists at Georgia Tech are calling this racket-swinging automaton ESTHER (Experimental Sport Tennis Wheelchair Robot), a robotic tennis player that can zip around the court and return human shots. The result is ESTHER, a modified tennis wheelchair that can race to balls at 10 meters per second and potentially outplay its human opponent. The device was named in homage to renowned wheelchair tennis player Esther Vergeer, who held the world No. 1 ranking in women’s wheelchair tennis from 1999 until her retirement in 2013.