Investigation of the Use of Bluetooth Sensors for Travel Time Studies under Indian Conditions

Travel time and its reliability are becoming increasingly important for a variety of real time applications such as Advanced Traveller Information Systems (ATIS), Route Guidance Systems (RGS) etc. which are a part of the Intelligent Transport Systems (ITS). They assist the road users in making timely decisions regarding their trip such as departure time, mode choice, route choice etc. There are various sensors which capture and monitor the travel time across a study corridor. However, their performance under Indian conditions is a major concern due to the vast heterogeneity in vehicle classes and the lack of lane discipline. Data from the GPS units equipped in the public transport buses are the current source of reliable travel time information. But these buses account for only 1% of the total traffic and have an inherent modal bias. One such technology which can capture data from across the vehicle classes and from any roadway of interest is the Bluetooth sensor. This study reports on the use of a Bluetooth based sensor to capture the travel time data and evaluate the reliability along two alternate routes in Chennai, India. Results from the cumulative frequency diagrams (CFD's) which are used to evaluate the reliability are also compared against the various reliability index measures.