Three targeted vehicles of varying size were measured using an optimized, practical photogrammetry technique and the results were compared to measurements acquired via total station. The photogrammetry method included the use of a field-calibrated DSLR camera equipped with a fixed 20 mm lens, retroreflective targets sized for vehicular modeling, and a CNC-machined scale bar. Eight photographs were taken from proper angles and processed using a commercially available photogrammetry package. This data was merged with the total station data using a cloud-to-cloud registration process for point-to-point comparison of positional data. The average residual between corresponding photogrammetry and total station points was 1.7 mm (N = 258, SD = 0.8 mm) with a 95% confidence limit of 3.1 mm. Considering this low residual, one of the sample vehicles was re-measured using a high accuracy FaroArm for comparison to the photogrammetry technique. The average residual between corresponding photogrammetry and FaroArm points was 1.2 mm (N = 83, SD = 0.56 mm) with a 95% confidence limit of 2.1 mm. This research shows photogrammetry can be highly accurate and efficient with proper methodology, while also expanding on the photogrammetry literature database and improving confidence in the technique.

<div class="section abstract"><div class="htmlview paragraph">Recent Tesla models contain four integrated onboard cameras that serve the Autopilot and Self-Driving Capabilities of the vehicle and act as a dashcam by recording footage to a local USB drive. The purpose of this study is to analyze the footage recorded by the integrated cameras and determine its suitability for speed determinations of both the host vehicle and surrounding vehicles through photogrammetry analyses. The front and rear cameras of the test vehicle (2019 Tesla Model 3) were calibrated for focal length and lens distortion characteristics. Two types of tests were performed to determine host vehicle speed: constant-speed and acceleration. Several frames from each test were analyzed. The distance between camera locations was used to gather vehicle speed through a time distance analysis. These speeds were compared to those gathered via the onboard GPS instrumentation. Two additional types of tests were performed to determine surrounding vehicle speeds: a vehicle approaching from the rear and an offset vehicle approaching from the front. For both tests, the Tesla was stationary. Several frames from each test were analyzed via reverse projection, using a point cloud of the approaching vehicles. The speeds obtained through photogrammetry were compared to GPS instrumentation onboard the approaching vehicle. The mean difference between photogrammetry and GPS instrumentation ranged between 0.38 and 0.72 mph across all tests.</div></div>