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The relationship between occupant crash injury and occupant compartment intrusion is seen in the perspectives of the velocity-time analysis and the NCSS statistical data for two important accident injury modes, lateral and rollover collisions. Restraint system use, interior impacts, and vehicle design features are considered. Side impact intrusion is analyzed from physical principles and further demonstrated by reference to staged collisions and NCSS data. Recent publications regarding findings of the NCSS data for rollovers, as well as the NCSS data itself, are reviewed as a background for kinematic findings regarding occupant injury in rollovers with roof crush.

Analytical reverse projection is introduced and is shown to offer an improvement in applicability and accuracy over other techniques of single-image photogrammetry, including plane-to-plane transformation and camera reverse-projection methods. A comparison of the methods is made on the basis of a single case of reconstructing missing tire tracks on a roadway intersection. Advantages and disadvantages of each method are discussed. THIS PAPER REVIEWS non-graphical techniques used to make measurements of features imaged in a single photograph. Two formulations of the plane-to-plane transformation method are re viewed, the camera reverse-projection technique is presented, and a third technique, called the analytical reverse-projection method, is introduced. Following a review of the various methods, including an indication of their advantages and disadvantages, each method is applied to the problem of relocating a set of tire tracks in an intersection.

The determination of appropriate friction coefficient values is an important aspect of accident reconstruction. Tire-roadway friction values are highly dependent on a variety of physical factors. Factors such as tire design, side force limitations, road surface wetness, vehicle speed, and load shifting require understanding if useful reconstruction calculations are to be made. Tabulated experimental friction coefficient data are available, and may be improved upon in many situations by simple testing procedures. This paper presents a technical review of basic concepts and principles of friction as they apply to accident reconstruction and automobile safety. A brief review of test measurement methods is also presented, together with simple methods of friction measurement to obtain more precise values in many situations. This paper also recommends coefficient values for reconstruction applications other than tire- roadway forces.