Applying Time-to-Collision in Collision Avoidance Systems

Rear-end collisions is frequent type of traffic accidents, in which human errors is the most dominant factor. Along with the recent technological developments in the field of driving task automation like developing advanced driving assistance systems (ADAS), human role in vehicle controlling is changing from a controller to a supervisor, and for this reason traffic crashes are decreasing gradually. Developing such systems like, AICC, ACC and CAS needs detailed data about human driving behaviors and reactions in different situations. So it is important to define a proper warning strategy that, warns driver when he/she is really at danger and immediate reaction is required. Previously, Time-to-Collision (TTC) has proven to be an effective measure for discriminating critical from normal behavior and so could be used in ADAS as a cue for decision-making in traffic. This paper deals with applyingtwo new safety indicators derived from TTC, named TET and TIT instead of TTC.