Motorized Two-Wheeler Overtaking: An Analysis of Strategies and Factors Affecting Overtaking Duration on Undivided Highways in Heterogeneous Traffic Conditions

Abstract

The increasing penetration of motorized two-wheelers (MTWs) on road networks of developing countries and their growing share in road crashes necessitate efficient driver assistance systems to support drivers in risky and hazardous situations. MTWs exhibit complex maneuvers while driving. Overtaking is one such complex maneuver from a safety viewpoint. While a few studies have explored this topic, none have modeled overtaking duration in heterogeneous traffic conditions. The present study investigates the overtaking behavior of MTWs and identifies the factors affecting the total overtaking duration using a hazard-based duration approach. For this purpose, a field study was conducted using instrumented MTWs, and a total of 250 overtaking maneuvers were observed in which 154 (62%) occurred in the same lane, called overtaking with lane sharing. The remaining 96 (38%) happened with a lane change, referred to as overtaking with lane changing, which is a unique finding with respect to overtaking strategies opted by MTW riders. It was found that the mean overtaking duration and overtaking distance for lane sharing were 5.2 s and 63 m, and for lane changing were 5.4 s and 59 m, respectively. Subsequently, hazard-based duration model results reveal that overtaking duration was found to be positively related to the initial gap, final gap, speed of the overtaken vehicle, and multiple overtaking. In contrast, the speed of the overtaking (instrumented MTW) vehicle has a negative impact on overtaking duration. The study findings will enable the development of an advanced rider assistance system for overtaking support of MTW riders.