It's from a long time ago when human policemen directing traffic were replaced by traffic lights .........or robotic policemen.
c. Chiefly S. Afr. An automatic traffic-signal.
1931 Even. Standard 5 Aug. 2/1 (heading) Traffic ‘Robots’ in the City. 1939 Forum (Johannesburg) 4 Feb. 35/1 The Daily Dispatch, East London, is critical of a proposal to fix robots in the town's streets. 1948 H. V. MORTON In Search of S. Afr. 17 Another word used in South Africa, but long discontinued in England, is robot for traffic lights. 1958 Johannesburg Star 16 Dec. 6/7 Johannesburg drivers..want to turn right or left while pedestrians, with the robot in their favour, are crossing. 1969 A. FUGARD Boesman & Lena II. 38 When the robot said ‘Go’ there at Berry's Corner I was nearly bang in my broek. 1974 Eastern Province Herald 2 Oct. 9 Vandals removed the lamps from seven traffic robots and the flashing head from a warning pole.
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