Date of Award
Doctor of Philosophy
John C. Hungerford
Tyler Kress, Stephen Richards, Kenneth E. Kirby, Lee Han
This dissertation presents a methodology to determine the approximate closing speed of a striking vehicle and resultant delta-v of the struck vehicle in low speed collinear rear impacts through analysis of the paint damage pattern evident on the struck vehicle's rear bumper. This methodology is only applicable to collisions between vehicles that possess painted flexible plastic foam supported bumpers. Five impacts at each of 2.5, 4.1, and 5.9 mph mean speeds and three impacts at 8.1 mph mean speeds were conducted to provide the foundation for this methodology.
The use of powdered guidecoat is introduced to contrast the damage pattern on the bumper of the struck vehicle. A measurement of the damage area is obtained and that damage area is then correlated to a closing velocity between the two vehicles. Empirically measured coefficients of restitution and calculated quantities of energy absorbed are also presented for each impact.
The relationship between struck vehicle paint damage area and impact speed was found to be strongly statistically significant (p < 0.001). A positive correlation was found between struck vehicle bumper paint damage and struck vehicle delta-v, with an r-value of 0.978 at a statistically significant level (p < 0.001). The applied paint film thickness was measured for each bumper and found to have no statistically significant effect on paint damage area (p = 0.108). The research proved that bumper cover paint damage could be used to determine certain kinematic parameters of the vehicles involved in the impact to a reasonable degree of accuracy. A fascia damage scale is provided at the conclusion of the work that concisely summarizes the results.
Anderson, Bryce Otis, "Low Speed Crash Testing: Establishment of the Anderson Fascia Damage Methodology. " PhD diss., University of Tennessee, 2006.