Vehicle Dynamics

ME5670

Date: 01/01/2015

Instructor: Ashok Kumar Pandey Email: ashok@iith.ac.in

Class timing Monday: 2:30 4:00 PM Thursday: 4:00 5:30 PM

Fundamental Definitions

Vehicle Dynamics It concerns with the movements of vehicles on a road surface

Physical condition Acceleration and braking, ride, and turning

Dynamic behavior Forces on the vehicle due to tires, gravity, and aerodynamics.

Objective

Vehicle and its components are studied to determine forces produced by the sources at particular maneuver and trim

condition

How the vehicle responds to these forces.

Representation

One mass

approximation

Located at its C.G.

Two masses

approximation

For acceleration,

braking, and most

turning analysis.

For ride analysis,

wheels are treated

as separate

lumped masses Body mass as sprung mass.

Wheel mass as unsprung mass.

Vehicle Dynamics Interaction

Separating driver from the disturbances

It implies the rejection of disturbance

Absence of disturbance amplification

Engine vibration and noise

Aerodynamic interaction (crosswinds, wakes, etc)

Road undulation

Vertical

Longitudinal

Lateral

Internally generated disturbance

Externally generated disturbance

Vehicle dynamics

Isolation Control

Forces/effects

Refinement Ride

Path Speed

Stability

Agility

Fidelity

Linearity

Handling Performance

Subjective Objective

Course Content Vehicle Mechanics Forces under static and dynamic equilibrium.

Free body diagram of different vehicle components such as tire, braking, suspension,

chassis, car body, gear box, clutch system, power steering, chassis, car body.

Simple linearized rigid models of different components.

Dynamic stability and the vehicle performance under different operating conditions such as

- understeering, neutralsteering, oversteering, and - factors associated with the vehicle-terrain interaction. Concept of vehicle ride comfort.

Introduction to random excitation and electronics stability controls.

Performance characteristics of a comfort vehicle ride.

Introduction to the development of one-dimensional vehicle driveline using different

softwares such as MATLAB Simulink/ADAMS/Carsim.

Introduction to advanced topics in the accurate modelling of vehicle dynamics Nonlinear models considering large deformation and material nonlinearity.

Grading Scheme

Attendence: 10%

Assignments:15%

Mid Term: 30% Project report: 15% Final Term: 30%

References

1. Thomas Gillespie, Fundamentals of Vehicle Dynamics, SAE, 1992. 2. Dean Karnopp, Vehicle Dynamics, Stability, and Control, Second Edition, CRC Press, 2013. 3. Giancarlo Genta, Motor Vehicle Dynamics-Modeling and Simulation, World Scientific, 2013 3. Giancarlo Genta and Lorenzo Morello, The Automotive Chasis- Volume 1 and 2, Springer, 2009. 4. John C. Dixon, Tires, Suspension and Handling, SAE, 1996. Herb Adams, Chassis Engineering: Chassis Design, Building & Tuning for High Performance Handling, Brownian Dynamics, HP Trade, 1992

Softwares: Carsim, BikeSIm, ADAMS, SYSTEM MODELER/MAPLESIM, MATLAB SIMULINK, SOLID EDGE/UNIGRAPHICS,