Deceleration Factors on Off-Road Surfaces Applicable for Accident Reconstruction

This paper presents the results of full scale testing completed to examine deceleration factors, or friction coefficients, on various off-road and on-road surfaces. Of particular interest is the relationship between vehicle side slip and deceleration rates on soft, off-road, deformable soils. Vehicle testing was conducted at slip angles of 0, 30, 45, 60, and 90 degrees with locked and unlocked wheels. A comparison of the experiment data is made with respect to the theoretical prediction of deceleration being trigonometrically related to slip angle. Results indicate the theoretical prediction as fairly approximate through a portion of the side slip range. As side slip angles approach 90 degrees, actual measured values are higher than predicted. (A) For the covering abstract of the conference see IRRD 882390.