Vehicle Dynamics: Fundamentals and Ultimate Trends
September 2, 2019 — September 6, 2019
- Basilio Lenzo (Sheffield Hallam University, Sheffield, UK)
Since the invention of the world's first motor vehicle, more than 100 years ago, automobiles have been widely accepted in our society with the progress of modern industry. The study and understanding of vehicle dynamics has always played a crucial role in the design of vehicles, with the aim of guaranteeing safety and stability as well as good performance. The recent advent of electric vehicles and the future perspective of widespread autonomous cars have posed further interesting challenges for the vehicle dynamicist, both in industry and academia. Nonetheless, the importance of the basics should never be underestimated - after all, essentially a vehicle behavior is described by second Newton's law, F=ma.
Therefore, the aim of this course is to recall the fundamentals of vehicle dynamics, as well as to present and discuss the state-of-the-art of ultimate trends in the field, including torque vectoring control, vehicle parameter estimation, and autonomous vehicles. The 6 lecturers include 2 eminent academics, 2 experienced researchers, and 2 industrial representatives.
The course will begin with a discussion of vehicle dynamics fundamentals. It will introduce classic hypotheses of vehicle dynamics theory, vehicle models for handling and performance, with a critical and often questioning approach. The handling of road cars will be also covered, with particular attention to the handling diagram and to the critical analysis of classical concepts such as understeer and oversteer. Since the vehicle performance and cornering depends strongly on the basic geometric properties of roads and suspensions, the lectures will then focus on suspension kinematics and compliance, engineering and measurement, as well as steering design and development. Another aspect of paramount importance which will be discussed is tire modeling and testing. Indeed tires allow the generation of the contact forces which rule the vehicle dynamics. A good representation of tire behavior is therefore a necessity, but is not a simple task. Furthermore, often thermal effects have a significant impact on tire behavior.
The second part of the course, dedicated to ultimate trends, will begin with the discussion of a relatively recent technology: torque vectoring, i.e. the ability to allocate desired amounts of torque to specific axles/wheels of a vehicle, aimed at the enhancement of vehicle safety and handling qualities, as well as battery life. Advanced vehicle control techniques, including torque vectoring, may require parameters such as tire-road friction coefficient or vehicle sideslip angle, which are difficult to obtain. Hence the lectures will discuss advanced techniques for their estimation. The last part of the course will be devoted to the autonomous driving. As well-known, advances in computational capabilities, communication architectures, as well as sensing and navigation devices have led to the development of autonomous vehicles with increasing level of automation. They must be able to construct a proper representation of the environment and of their own state, and to make timely decisions in order to act with the external environment in an optimal and safe way.