Assessing the Effects of Interchange Warning Systems on Driving Risk: A Driving Simulator Study

Table 1

Simulation scenarios and working mode of IWS.

Scenario description	IWS function	Scenarios
Ramp section: the test vehicle traveled along the ramp	The vehicle was traveling along the ramp, the yellow light on the roadside inducer in front of the vehicle was flashing, and the three RSUs behind the vehicle were flashing red and following the vehicle to form a trail
Merging section: test vehicles travel along the expressway and encounter vehicles merging from the ramp onto the expressway	No vehicles enter the expressway from the ramp, and the RSUs flash yellow lights. Vehicles enter the expressway, and the RSUs within a 150 m range of the expressway flash red lights, while the three RSUs behind the vehicle on the ramp flash red lights to form a trail
Diverging section: test vehicles travel along the expressway and encounter vehicles entering the ramp from the expressway	No vehicles enter the ramp from the expressway, and the RSUs flash yellow lights. Vehicles exit the mainline of the expressway, and the RSUs within a 150 m range of the mainline flash red lights, while the three RSUs behind the vehicle on the ramp flash red lights to form a trail
Ramp accident section: test vehicles encounter accident vehicles ahead while driving on the ramp	No traffic accidents on the ramp, and the RSUs flash yellow lights. When there is an accident on the ramp, the RSUs after the accident site flash red lights

Symbol: RSUs (yellow), RSUs (red), test vehicle, other vehicle, accident.