Faced with truck drivers not heeding warnings when their tractor trailers were too tall to enter the Sydney Harbour Tunnel, officials turned to a company called Laservision to put an end to these costly crashes that were not only closing the tunnel for weeks at a time, but also put other drivers on the road in considerable danger.
Laservision's Softstop system projects a familiar bright red stop sign, seemingly in mid-air, at the tunnel's entrance if a vehicle too large to enter is detected. In fact, the stop sign does not float in mid-air, but rather is projected onto a water screen that, should a vehicle not heed its command, would cause no damage from being driven through.
(thanks Cora)
