Automation of the Two-Second Rule via Constant Time-to-Collision Curves

Since 2021 a new traffic control rule was proposed to the drivers running on highways: the two-second rule, stating that a driver should ideally stay at least two seconds behind the preceding vehicle. The two-second rule is easily understandable by drivers and is perfectly adapting distance gaps between vehicles to their actual speeds. On the other side this rule is hard to automate. The 2-second rule is deeply connected with the Constant Time to Collision criterion (CTTC), introduced in 2006, which is measuring the distance gap between following cars by the time required for the following cars to collide, assuming unchanged speeds for both vehicles. CTTC was experimentally tested in 2013, on the occasion of a doctoral thesis defended by F. Mensing and supported by the Renault group. This work is proposing to automate the 2 second rule by using CTTC curves as planners for the cruise controllers of any specific automobile model.