Brach Engineering, LLC.

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Professional Development Seminar

Vehicle Accident Reconstruction Methods

Raymond M. Brach and R. Matthew Brach

Ray Brach and Matt Brach taught the SAE Professional Development seminar on accident reconstruction from 2004 until 2010. While Ray and Matt no longer teach the very popular Accident Reconstruction class at SAE, Brach Engineering makes that same class available to be taught at your company. The material presented in the seminar parallels the material contained in the book Vehicle Accident Analysis and Reconstruction Methods. The seminar includes additional examples beyond those in the book.These examples are contained in the class notes provided to the attendees of the seminar and covered as part of the class.

This seminar is available in either the one, two or three-day format, to companies and agencies for presentation to groups involved in the reconstruction and analysis of crashes. The three-day format includes all the available topics as well as a hands-on section in which the attendees actually reconstruct an accident using software. Arrangements can be made for a custom seminar where interested companies may pick and choose topics to be covered.

If you are interested in the Professional Development Seminar, please fill out the form below.

Seminar Schedule
  1. Uncertainty and Sensitivity in Measurements and Calculations
    Methods of estimating uncertainty – upper and lower bounds, differential variations, finite differences, Monte Carlo, DOE and statistics of related variables.
  2. Straight-Line Motion
    Equations of motion of 2-axle vehicles including pitch motion and load transfer due to braking/acceleration plus coverage of values of the frictional drag coefficient, ƒ, of light vehicles and heavy trucks.
  3. Point Mass Collisions
    Fundamentals of the concepts of impact theory: impulse, momentum, velocity change, ΔV, energy loss, normal & tangential impulses — some simple applications.
  4. Planar Impact Mechanics (PIM)
    Thorough coverage of the system equations and solution equations of impulse and momentum for the collision of 2 vehicles including rotational inertia and angular momentum. Essential for the analysis and reconstruction of crashes using EDR data.

    Class computer participation using Planar Impact Mechanics software (VCRware).
  1. Crush and Tangential Energy Loss
    Introduction to the concepts of crush measuements (CRASH3) to compute collision energy loss and its relationship to crash vehicles’ ΔV.
  2. Event Data Recorder (EDR) Technology
    Introduction to the general characteristics of EDRs: driver and vehicle states (settings), time intervals, 5 seconds of precrash data, crash acceleration & ΔV.
  3. Crash Reconstruction using EDR Data, Planar Impact Mechanics and Spreadsheet Optimization Techniques.
    Coverage of the use of Planar Impact Mechanics for analysis & reconstruction of crashes using VCRware. Class participation.
  4. Frontal Vehicle-Pedestrian Collisions
    Introduction to and derivation of the equations of the Han-Brach pedestrian impact model and other pedestrian impact models.
  1. Planar Photogrammetry
    Determination of road surface markings from photographs.
  2. Mechanics and Modeling of Tire Forces
    Description of longitidunal tire forces (braking/acceleration), lateral tire forces (steering/cornering) and tire forces under combined braking and steering. Friction ellipse. Modeling of tire forces using the Bakker-Nyborg-Pacejka (BNP) equations and the modified Nicolas-Comstock equations. Antilock braking principles.
  3. Critical Speed from Tire Yaw Marks
    Description and measurement of yaw marks and reconstruction of vehicle speed at the beginning of yaw marks.
  4. Articulated Vehicle Impact
    Concepts of impulse and momentum applied to crashes between articulated vehicles (such as tractor semitrailers).
  5. Topics from Vehicle Dynamics
    Discussion of vehicle dynamic simulation: uses — software — input parameters.

Reconstruction Seminar Presentation Request Form

Thank you for filling out our Reconstruction Seminar Presentation Request form. An e-mail has been sent to us, and we will contact you soon to set up the details of your presentation request and address any questions/concerns you may have had.