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<div class="section abstract"><div class="htmlview paragraph">Many new vehicles come equipped with Advanced Driver Assistance Systems (ADAS) as standard or optional features. These technology packages frequently include Lane Departure Warning (LDW), an electronic system designed to alert the driver when the vehicle begins to depart from its lane. These systems identify lane boundaries using computer analysis of video captured by a forward-facing camera, typically mounted near the rear-view mirror. Some vehicles are also equipped with Lane Keeping Assist (LKA). Upon detecting an unintended lane departure, LKA will make electronic steering and/or braking control inputs to keep the vehicle in its original travel lane. Four vehicles equipped with LDW and LKA were tested: a 2019 Toyota Corolla, 2019 Honda Civic, 2020 Ford Explorer, and 2019 Chevrolet Tahoe. Tests were conducted on a straight, flat road with clear lane markings. Lane departures to the left and to the right were initiated by the test driver at 45 and 65 mph. Using a VBOX 3i RTK DGPS, data related to the vehicle’s speed, acceleration, and driver- and software-related control inputs were collected via the vehicle’s CAN bus. Additionally, the VBOX collected vehicle location data of ±2 cm (±0.79 in) accuracy relative to survey points. Analysis of test data yielded details of system-level behaviors. For LDW, the average warning issue point (lateral distance prior to reaching the lane boundary) observed was 1.33 ft, the average rate of departure (lateral velocity) was 1.45 ft/s, and the warning occurred 0.76 sec before lane departure. Lane keeping actions began, on average, 1.13 ft from the lane boundary (0.66 sec before lane departure) and involved 4.81 degrees of steering with an average maximum lateral acceleration of 2.86 ft/s² (0.09 g). The LKA systems tested permitted the vehicles’ outside tires to exceed the lane boundaries by an average of 0.14 ft.</div></div>

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<div class="section abstract"><div class="htmlview paragraph">Every day in the United States, an average of approximately two cyclists die in bicycle accidents. Sometimes, forensic engineers are asked to reconstruct these accidents. These cyclists may use bicycle GPS devices to record important data, which they use to monitor their riding activities. By analyzing this data, many questions can be answered regarding various parameters such as speed, position, and riding behavior of the bicyclist.</div><div class="htmlview paragraph">The goal of this study was to analyze the accuracy of the GPS position and speed data. For this study, four different bicycle GPS devices (one of which was paired with a magnetometer Garmin Bicycle Speed Sensor), a GoPro camera equipped with GPS, and a smartphone recording to Strava, were mounted on a bicycle. The bicycle was ridden in an approximately straight line (back and forth), and then around a building, to measure positional and speed accuracy. Additionally, the bicycle was ridden in a straight line, then decelerated to a complete stop for varied durations, and then accelerated forward. This was done to see if the retrieved data showed the bicycle coming to a complete stop, or if the GPS averaged a few data points showing that the rider never came to a stop. Furthermore, the bicycle was stopped at a specific location for a certain duration and the GPS drift of each device was studied. </div><div class="htmlview paragraph">Using VBOX 3i RTK DGPS positional data as the reference, test data revealed that all six bicycle test devices had relative error in positional and speed data. The Garmin Edge 530 had an average speed error of 10.83% and positional error of 21.78 ft. The Garmin Edge 1000 (BSS) had an average speed error of 4.71% and positional error of 15.2 ft. The Lezyne Mega XL had an average speed error of 3.5% and positional error of 4.82 ft. The Wahoo ELEMNT Bolt had an average speed error of 3.53% and a positional error of 10.46 ft. The Strava app had a positional error of 11.45 ft. The GoPro Hero5 had an average speed error of 5.05% and a positional error of 4.79 ft.</div></div>