Forensic Engineering Determination Of The Angle Of Lean Of A Cycle-Rider System Negotiating A Turn

Abstract

For A Cyclist To Negotiate A Turn, They Must Lean The Bicycle To The Inside Of The Corner In Order To Balance The Centrifugal Force Associated With The Change In Velocity And The Gravitational Force From Gravity. The Vector Sum Of These Two Forces Will Be Directed Between The Center Of Gravity Of The Rider And The Contact Patch Of The Tire On The Road Surface. The Force On A Rider During A Turn Is Dependent Upon The Radius Of The Turn, And The Velocity Of Travel. The Lean Angle Of The Cyclist Is Determined By The Alignment Of The Centrifugal Force And The Riders Weight So As To Have The Gravitational And Inertial Forces Directed From The Center Of Mass Of The Rider To The Contact Patch Of The Tire On The Road. This Force Balance Gives The Basic Equations For The Turning Phenomena. The Analysis Then Gives The Relationship Of The Factors Of A Rider In A Turn As A Function Of Speed, Radius Of Curve And The Angle Of Lean. The Purpose Of The Analysis Is To Give The Forensic Engineer The Ability To Reconstruct The Limits Of The Turning Movement Of A Cyclist In An Accident Scenario.