1st Edition

Vehicle Crash Mechanics

By Matthew Huang Copyright 2002
    498 Pages 589 B/W Illustrations
    by CRC Press

    Governed by strict regulations and the intricate balance of complex interactions among variables, the application of mechanics to vehicle crashworthiness is not a simple task. It demands a solid understanding of the fundamentals, careful analysis, and practical knowledge of the tools and techniques of that analysis.

    Vehicle Crash Mechanics sets forth the basic principles of engineering mechanics and applies them to the issue of crashworthiness. The author studies the three primary elements of crashworthiness: vehicle, occupant, and restraint. He illustrates their dynamic interactions through analytical models, experimental methods, and test data from actual crash tests. Parallel development of the analysis of actual test results and the interpretation of mathematical models related to the test provides insight into the parameters and interactions that influence the results. Detailed case studies present real-world crash tests, accidents, and the effectiveness of air bag and crash sensing systems. Design analysis formulas and two- and three-dimensional charts help in visualizing the complex interactions of the design variables.

    Vehicle crashworthiness is a complex, multifaceted area of study. Vehicle Crash Mechanics clarifies its complexities. The book builds a solid foundation and presents up-to-date techniques needed to meet the ultimate goal of crashworthiness analysis and experimentation: to satisfy and perhaps exceed the safety requirements mandated by law.

    CRASH PULSE AND KINEMATICS
    Introduction
    Vehicle Impact Modes and Crash Data Recording
    Digital Filtering Practice per SAE J211 and ISO 6487
    Basic Kinematic Relationships
    Impact and Excitation: Vehicle and Sled Test Kinematics
    Vehicle and Occupant Kinematics in Fixed Object Impact
    Kinematic Variables
    Case Study: Single Vehicle-Tree Impact Accident
    Restraint Coupling
    Occupant Ridedown Analysis and Energy Management
    References
    CRASH PULSE CHARACTERIZATION
    Introduction
    Moment-Area Method
    Pulse Approximations with Non-Zero Initial Deceleration
    Pulse Approximations with Zero Initial Deceleration
    Fourier Analysis of Crash Pulse
    References
    CRASH PULSE PREDICTION--THE CONVOLUTION METHOD
    Introduction
    Transfer Function via Convolution Integral
    Transfer Function and a Spring-Damper Model
    Belted and Unbelted Occupant Performance with Air Bag
    Body Mount and Torso Restraint Transfer Functions
    Effect of Sled and Barrier Pulses on Occupant Response
    Other Applications
    Response Inverse Filtering
    References
    BASICS OF IMPACT AND EXCITATION MODELING
    Introduction
    Impact and Excitation--Rigid Barrier and Hyge Sled Tests
    Ridedown Existence Criteria and Efficiency
    Basics of Spring and Damper Dynamic Modeling
    Two-Mass and Effective Mass Systems
    Vehicle-to-Barrier Impact: Spring-Mass Model
    Spring-Mass Occupant Model Subjected to Excitation
    Vehicle-to-Vehicle Impact: Spring-Mass Model
    A Maxwell Model
    Impact on Kelvin Model--Vehicle or Component
    Damping Factor and Natural Frequency from Tests
    Excitation on the Kelvin Model--Occupant and Restraint
    References
    RESPONSE PREDICTION BY NUMERICAL METHODS
    Introduction
    Hybrid Model--A Standard Solid Model
    Two Mass-Spring-Damper Model
    Natural Frequencies in Two-Mass System
    Numerical Searching Techniques
    Loading and Unloading Simulation
    A Lumped-Parameter Model--CRUSH II
    Side-Impact and Frontal-Offset Models
    References
    IMPULSE, MOMENTUM, AND ENERGY
    Introduction
    Background
    Center of Gravity and Motion Theorem
    Impulse and Circle of Constant Acceleration
    Principle of Work and Energy
    Vehicle Inertia Properties and Critical Sliding Velocity
    Rollover Crashes
    Eccentric Loading on Vehicle Rollover
    References
    CRASH SEVERITY AND RECONSTRUCTION
    Introduction
    Occupant Motion Under Impact and Excitation
    Preloading on an Occupant
    Central Collisions
    Non-Central Collisions
    Use of DV and BEV of Vehicles in Crash Severity Assessment
    Vehicle Acceleration and Crash Severity
    Velocity and Energy Distributions in Two-Vehicle Impact
    Computation of Barrier Equivalent Velocity
    Intermediate Mass Effect
    Modeling the Vehicle-to-Vehicle Compatibility Test
    Accident Reconstruction Methodology
    References

    Biography

    Matthew Huang