Ex-ante evaluation of traffic signs using a traffic sign simulator

Traffic signs and pavement markings are a crucial aspect of road design since they are essential sources of information for road users to calibrate their driving behavior, evaluate route possibilities and cope with unexpected events. A pro-active evaluation of (the quality of) these road design elements will help to improve the safety performance of the roadway. The Traffic Sign Simulator is an innovative research tool to study road users’ comprehension of traffic signs, digital information panels and pavement markings, to investigate their influence on routing decisions (including lane choice) and to collect participants’ suggestions for improvements. Using a driving simulator mock-up, participants navigate through a full HD video from the route(s) in which the planned traffic signs have been digitally implemented using specialized software for camera-tracking and 3D video-integration. Participants’ route and lane choice and their visual behavior (using eye-tracking) are monitored while driving through the different scenarios. Laptop preand post-tests are applied to collect more in-depth information concerning the participants’ processing, comprehension and general evaluation of the traffic signs and suggestions for improvement. The paper also presents a case study that examines the temporary traffic signs, digital information panels and pavement markings during the reconstruction works on the Vilvoorde flyover (near Brussels), one of the busiest interchanges in the Belgian highway network. The traffic sign plan in the work zone of Vilvoorde has been evaluated ex-ante because highway work zones are often a major cause of serious accidents due to the temporarily changed road situation.