Background

A roundabout is a type of road junction in which traffic moves in one direction (counterclockwise in right-hand traffic countries such as Sweden) around a central island. During the several last decades, roundabouts have become a very popular traffic solution because of their superiority over classical intersections in several aspects. The construction of a roundabout improves safety (a vast reduction of accidents especially fatal ones) and operations (reduced congestion and delays), brings lower maintenance costs (no signal hardware or equipment maintenance), reduces pollution (less noise and better air quality due to lower fuel consumption), and improves the aesthetics of a junction. In this project, the focus is on traffic flow in roundabouts, especially on gap acceptance that dictates traffic operations.

On the other hand, vehicle design has experienced radical changes also during last several decades when a classical “car box” has been replaced with a variety of artistic and futuristic shapes. This poses certain challenges for the placement of the direction-indicator lamps especially in the front part of the vehicle. Although technical prescriptions for the position and geometrical visibility of direction-indicator lamps exist, they allow some degrees of freedom to vehicle manufactures. In this project, the geometrical visibility of front direction-indicator lamps is in focus.

Project objectives

Given that the driver of an entering vehicle looks for a gap in circulating traffic, it is important, especially in heavy traffic, to observe on time if the vehicle in the roundabout signals an intention to exit. Therefore, the aim of this project is to examine whether the geometrical visibility of the front direction-indicator lamps could have any effect on traffic flow in roundabouts.

The method

Two methods will be applied. In the first part of the project, the task includes the development of camera-based system for mapping the geometrical visibility of the front direction-indicator lamps in a 3D space. The measurements will be done on a selected number of real vehicles. The second part of the project includes computer simulation using models of a selected number of real roundabouts in Sweden, and the data collected in the first part of the project.

Qualifications and conditions for the project

Two motivated students should apply for this Master thesis project. The students should have good knowledge of Matlab. The duration of the project is up to one year. After the successful completion of the project, the students will receive 30 or 60 credit points depending on the work duration.

Contact

Professor Mattias Wahde
Phone: 031- 772 3727
E-mail: mattias.wahde@chalmers.se

Postdoctoral researcher Igor Radun
Phone: 031- 772 3604
E-mail: igor.radun@chalmers.se

6.5.5. Geometric visibility

6.5.5.1. Horizontal angles (see figure below)

Vertical angles: 15^o above and below the horizontal for direction-indicator lamps of categories 1, 1a, 1b, 2a, 2b and 5. The vertical angle below the horizontal may be reduced to 5^o if the lamps are less than 750 mm above the ground; 30^o above and 5^o below the horizontal for direction-indicator lamps of category 6. The vertical angle above the horizontal may be reduced to 5^o if the optional lamps are not less than 2,100 mm above the ground.

For M₁ and N₁ category vehicles, the value of 45^o inward for the direction-indicator lamps of categories 1, 1a or 1b, whose lower edge of the apparent surface is less then 750 mm above the ground, may be reduced to 20^o under the horizontal plane containing the reference axis of this lamp.

Vehicle regulation is under UN/ECE E-regulations (wider than EU). Lightning belongs to E48 http://www.unece.org/trans/main/wp29/wp29regs/r48r6e.pdf