Kiwi ITS tackles speedsters

Studies on variable speed-limit technology on New Zealand’s roads show it’s helping reduce the risk of fatalities. The rural intersection active warning system (RIAWS), which has been developed by Kiwi company Armitage Group, is designed to display a temporary 70kph speed limit when potential conflicts, such as a right-turning vehicles on main roads, arise. Sensors on roads before the intersection trigger electronic signs to display the speed limit. When there are no crossing or turning vehicles at the location, the signs are blank and through vehicles are uninterrupted to maintain efficiency. At one intersection, the risk of a vehicle’s passengers being killed or seriously injured dropped from 60 to 25 per cent after the system was put in place. The success of the programme has resulted in a trial of a school bus electronic speed-limit signs, which display 20kph when a bus has stopped to drop or pick up children. Hamish Mackie, director of Mackie Research and Consulting, says the system is effective because the signs catch attention well-ahead of the sign by showing a flash and then the speed limit. He says: “Drivers are told exactly what to do, removing uncertainty about speeds.”