<div class="section abstract"><div class="htmlview paragraph">Video recordings of vehicular collisions have become widely available to the accident reconstructionist and can play a vital role in determining the locations and speeds of the subject vehicles involved in a collision. However, due to varying video resolutions, framerate, lens distortion, motion blur, and camera movement, errors in video analysis can occur. To understand the total error inherent to video analysis, this study presents analysis of videos from different video systems, the limitations in the analysis, and a comparison of video analysis speeds to reference datasets. The factors that influenced variance included resolution, lens correction, shutter speed, and framerate. The video systems analyzed included three moving cameras and two stationary units.</div><div class="htmlview paragraph">In the present study, a mock collision scenario in which a target vehicle approached a recording vehicle head-on, was staged to emulate an actual event captured on video. The target vehicle’s speed was analyzed using the captured videos. The video analysis results were then compared to the speeds obtained from the target vehicle’s wheel speed sensors via a VBOX system connected to the vehicle’s Controlled Area Network (CAN), and VBOX GPS position data.</div><div class="htmlview paragraph">The videos were recorded from two locations. Location 1 was at the top corner of a business complex. This location was equipped with two video cameras: a GoPro HERO5 and a Sony α6400 mirrorless camera. Location 2 was within the recording vehicle itself. This location was equipped with three video systems: a 2018 Tesla Model 3 Dashcam video camera system, a generic dashboard video system with a low framerate, and a Blackmagic Design camera. Videos were captured as the recording vehicle moved towards the target vehicle; the camera’s location and angle relative to the target were constantly changing.</div><div class="htmlview paragraph">Errors in the determined speeds were quantified based on comparison of the video analysis speeds to the reference datasets. The errors in speed were determined to be inversely correlated to the video resolution. Additionally, the analysis of the video footage from the stationary source yielded lower error than the analysis of the moving vehicle video for a given resolution and framerate.</div></div>

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<div class="section abstract"><div class="htmlview paragraph">There is extensive literature on motorcycle skid/brake to stop testing on a host of motorcycle types, rider experience, brake system configurations and the associated deceleration rates. Very little information exists on deceleration rates involved with over-braking the front wheel. The subject of this paper addresses the deceleration rates of sport bike type motorcycles during over-braking of the front wheel. Based on the physics of a two-wheeled vehicle like the motorcycle, once the front wheel is over-braked and becomes locked, the rider has very little time to recover from the skid and often times falls. Another over-braking scenario, especially on sport bike type motorcycles, is the possibility of the rear wheel lifting and pitching over the front wheel. During the initial phase of braking, weight transfer to the front wheel occurs creating a greater level of traction. As the motorcycle begins to fall or pitch over, the weight on the front wheel decreases significantly and therefore the frictional force decreases significantly as well. The goal of this publication was to perform maximum front wheel brake testing that involves front wheel skid-to-fall as well as front wheel brake-to-pitch over scenarios on various sport bike motorcycles and determine an applicable deceleration rate.</div><div class="htmlview paragraph">Three motorcycles; a 2002 Kawasaki ZRX1200R, a 2006 Yamaha YZF-R6, and a 2013 Ninja EX300 were subject to various maximum front wheel brake tests. The speed of the motorcycle at brake application ranged from 50 to 60 mph. The results of the testing concluded that the average deceleration rates during front wheel skid-to-fall tests were in the range of 0.32-0.8g depending on the lean angle of the motorcycle at brake application. The average deceleration rates for the front wheel brake-to-pitch over tests were in the range of 0.8-0.86g.</div></div>