86466 - Motorcycle Vehicle Dynamics

Learning outcomes

Students are introduced to procedures and methods for modelling, identification, design, analysis of dynamical models of motorcycle systems. Tools: - analytical tools, to understand the basic system mechanical behaviour; - numerical tools, in order to simulate complex mechanical systems; - experimental tools, to make it possible critical parameters to be identified.

Course contents

• Motorcycle kinematics
  • geometry and kinematic parameters
  • steering angle and trim
  • tire cross section and trajectory in a turn
• Suspensions
  • architecture and kinematics of front and rear suspensions
  • stiffness and damping characteristics
  • determination of the reduced parameters
• Tire modelling
  • analytical models
  • semi-empirical models
  • tire-road contact forces
• Motorcycle dynamics
  • steady state rectilinear motion
  • in-plane vibration modes
  • road excitation models
  • analysis of the effects of the motorcycle response on grip/handling and rider’s comfort
  • transient rectilinear motion: acceleration and braking
  • steady turning
  • transient phases of cornering
  • gyroscopic effects
  • stability and motorcycle vibration modes
  • influence of the main design parameters on stability
  • techniques for experimental identification of the motorcycle modal parameters
  • rider-motorcycle interaction (brief introduction)

• Numerical modelling of the motorcycle dynamics
  • Lagrangian approach: stability in rectilinear motion; sensitivity analysis of the main parameters; stability in cornering; effects of structural stiffness on stability
  • modelling with commercial software: simulating maneuvers characterized by high non-linearity; simulating critical events and scenarios; simplified models for traction-control/anti-wheelie and/or anti-lock braking systems

• Experimental tests and model validation

  • experimental identification of physical parameters (mass, inertia tensor, tire characteristics, suspension characteristics, steering torque)
  • estimation of kinematic quantities
  • estimation of dynamic quantities
  • virtual tests for implementing strategies to optimize the motorcycle performance: case studies

Readings/Bibliography

• Cossalter V. Motorcycle Dynamics. 2nd ed. LULU, 2006.
• Pacejka HB. Tire and Vehicle Dynamics. 3rd ed. Oxford, Butterworth-Heinemann. 2012.
  

Teaching methods

The course comprises:

• theoretical lectures with blackboard, PowerPoint slides and the support of multimedia tools;
• lectures and seminars held by experts from Academia and Industry;
• classroom exercises with numerical tools and simulation software.

Assessment methods

Final examination on the program of the entire course. Three oral questions. The final score is given by the mean of the score for each question. A sufficient score is required for each question.

Office hours

See the website of Alberto Martini

See the website of Marco Ezio Pezzola