Research Papers

Ball-bank indicator and a vehicle's speed around a curve

Filename FINAL-PAPER-46.doc
Filesize 629 KB
Version 1
Date added June 10, 2012
Downloaded 5 times/fois
Category 2012 CMRSC XXII Banff
Tags Session 7B
Author/Auteur Francis (Frank) Navin


The ball-bank indicator has been used to help set the "safe speed" on highway curves since the 1930s. It is also used to set the advisory curve speed. The basic idea is to have the driver "feel safe and comfortable" travelling around a corner and this has been observed for specific angles at certain speeds. This paper derives an equation to relate the ball bank indicator angle value to the coefficient of friction generated during the turn. The precision of the results is investigated. The paper also compares the ball-bank indicator values and the observed lateral acceleration from a test track and a highway in British Columbia.

Francis (Frank) Navin