One hundred years of wheel shimmy: Why is it still dangerous?

Shimmy is a hard-to-predict vibration phenomenon of towed rolling wheels. Although it appears with low probability, it may cause catastrophic accidents. Low order models of shimmying wheels with single contact point and Coulomb friction exhibit the fundamental phenomenology. Local and global dynamic analyses explore parameter regions with bi-stability, isola, chaotic and transient chaotic oscillations. If there is pneumatic tire on the wheel, a certain time delay effect becomes relevant in the nonlinear dynamics of the system. Experimentally detected micro-shimmy onset is explained by carrying out a non-smooth bifurcation analysis that is related to the nonlinear effect of partial slipping within the tire/ground contact region.

Key Learning Objectives

• Single wheel shimmy is a dynamic contact paradigm
• The rich shimmy dynamics originates from the unique combination of the nonlinearly constrained spatial motion of a rigid wheel and the nonlinear elastic contact "where the rubber meets the road”
• The complex nonlinear phenomena of shimmying wheels are important for controlling new transportation devices like segways, unicycles, rollers, skateboards, snakeboards, powerslides, caster boards, hoverboards
• The nonlinear dynamics of shimmy can induce low-probability accidents with conventional wheeled transportation devices.

Who Should Attend

• Mechanical engineers
• Aerospace engineers
• Researchers/scientists in mechanical sciences and dynamics
• Research/Project managers
• Heads of research divisions in mechanical design, dynamics, tribology