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For model year 2018, Freightliner introduced the New Cascadia model to their lineup of Class 8 trucks. Testing of the Freightliner New Cascadia with Detroit Diesel engines was conducted to evaluate the accuracy of the reported event data contained in the engine Electronic Control Units (ECUs) for these trucks. The testing showed that there are occurrences in DDEC Reports, specifically in the Last Stop Record and Hard Braking event data, when the time between successive event data points was two seconds rather than the reported one second interval. The occurrence of the two-second anomaly was not always present in a Last Stop Record or Hard Braking event. When the two-second anomaly was present in the event data, it occurred randomly and no pattern to when this anomaly occurs was determined. No method was found to be able to detect the presence of this anomaly from the review of a Last Stop Record or Hard Braking event.

Using dashcam video footage to extract reliable vehicle speed data can be challenging when the only available image stream comes from a camera whose optical parameters are unknown. One means of overcoming such difficulties uses visible landmarks and features within the video frame whose dimensions can be independently measured. While good results have been obtained by others using a Total Station or LiDAR to physically measure locations for such purposes, this approach could prove difficult if a site of interest is inaccessible (e.g. on a busy highway that cannot be shut down) or if relevent features of the target location have changed (e.g. due to construction or even restriping of lanes lines). As an alternative to direct scene measurement, it is proposed that measurement of features visible in overhead satellite images be used to dimension relevant features visible in the video.

Scientific methodology and engineering techniques were applied to a series of three automobile rear-end collision experiments to provide data relating to seat, seat backrest, and head-restraint design. Five seat back heights and four seat back strength values were studied in connection with their practicality and relative protective features, when subjected to a 55 mph rear-end collision exposure. These research data provide a basic reference system of high-speed collision performance for seat designs with respect to occupant size and proximity to injury producing structures. Additionally, methodology, instrumentation, and related equipment required for post-crash fire studies were included in experiment 106, providing what is believed to be the first published data on the precise time-related events associated with collision-induced passenger car fires. Design revisions suggested by these findings are discussed.

Range anxiety in current battery electric vehicles is a challenging problem, especially for commercial vehicles with heavy payloads. Therefore, the development of electrified propulsion systems with multiple power sources, such as fuel cells, is an active area of research. Optimal speed planning and energy management, referred to as eco-driving, can substantially reduce the energy consumption of commercial vehicles, regardless of the powertrain architecture. Eco-driving controllers can leverage look-ahead route information such as road grade, speed limits, and signalized intersections to perform velocity profile smoothing, resulting in reduced energy consumption. This study presents a comprehensive analysis of the performance of an eco-driving controller for fuel cell electric trucks in a real-world scenario, considering a route from a distribution center to the associated supermarket.

One of the most promising solutions to address the twin problems of transport related pollution and energy security is to use alternative fuels. Compressed Natural gas (CNG) has been widely used in India to address the menace of pollution from commercial vehicles in cities like Delhi. Hydrogen blended compressed natural gas (HCNG) as a fuel has potential for further reducing harmful emissions and greenhouse gases. Enriching hydrogen in CNG improves combustion characteristic of CNG and reduces carbonyl emissions. Due to growing concerns over un-regulated emissions and their effect on human health, it is imperative to estimate un-regulated emissions from such alternatives for assessing overall impact of such fuels. Presently world over, emission legislations mainly addresses pollutants like CO, HC, NOx, CH4, NH3, PM etc. Relatively higher quantity in exhaust qualifies these pollutants to be monitored and controlled.

Data regarding the characteristics of left turns and lane changes performed by articulated tractor semitrailer combination vehicles in urban environments are presented. Previous studies have quantified acceleration rates for tractor semitrailers travelling straight, and for automobiles making left turns, but there is a gap in the literature regarding heavy vehicle acceleration during left turns. Likewise there is a lack of published data regarding the duration of lane changes made by these vehicles at highway speeds. Left turns were studied at a four-way stop-sign controlled intersection with a high volume of heavy vehicle traffic. Markings were made on the roadway corresponding to three left turn paths of varying radii. Intervals leading up to and along the marked paths were measured and painted on the roadway. The motion of each tractor semitrailer that made the subject left turn was recorded by video.

In 1980, research by Thebert introduced the use of photography equipment and transparencies for onsite reverse camera projection photogrammetry [1]. This method involved taking a film photograph through the development process and creating a reduced size transparency to insert into the cameras viewfinder. The photographer was then able to see both the image contained on the transparency, as well as the actual scene directly through the cameras viewfinder. By properly matching the physical orientation and positioning of the camera it was possible to visually align the image on the image on the transparency to the physical world as viewed through the camera. The result was a solution for where the original camera would have been located when the photograph was taken. With the original camera reverse-located, any evidence in the transparency that is no longer present at the site could then be replaced to match the evidences location in the transparency.

This paper reports the development of an operation support system for production equipment using image processing with deep learning. Semi-automatic riveters are used to attach small parts to skin panels, and they involve manual positioning followed by automated drilling and fastening. The operator watches a monitor showing the processing area, and two types of failure may arise because of human error. First, the operator should locate the correct position on the skin panel by looking at markers painted thereon but may mistakenly cause the equipment to drill at an incorrect position. Second, the operator should prevent the equipment from fastening if they see chips around a hole after drilling but may overlook the chips; chips remaining around a drilled hole may cause the fastener to be inserted into the hole and fastened at an angle, which can result in the whole panel having to be scrapped.

This paper defines the geometry of minimum weight tank structures of given enclosed volume. A tank structure is considered to comprise a circular cylindrical shell (monocoque or stiffened), bulkheads, and skirt structures. The analyses, starting from established criteria of failure, apply to the loading cases of longitudinal compression and bending moments in combination with internal pressure. The bulkhead geometries are flat, hemispherical, and ellipsoidal. For monocoque shells, the analyses yield the radius and wall thicknesses prescribing a minimum total weight of cylindrical tank wall, bulkheads, and skirts (unpressurized cylindrical appendages, for example, interstage structure). For stiffened shells, the analyses yield the tank radius, skin gauge, stringer spacing, and frame spacing prescribing a minimum total tank weight. An optimum relative geometry is defined for three types of stringers.

The Inflatable Tubular Structure (ITS) is a safety system intended to provide head protection during side-impact car accidents. The ITS is an inflatable device fixed at two points; at the front end, to the A-pillar, and at the aft end, to the roof rail behind the B-pillar. It is stowed over the side window under the trim of the A-pillar and the headliner. At one end, a gas generator is electrically connected to the side-impact crash-sensing system which inflates the ITS when needed. The ITS is fabricated in a unique way so that, upon inflation, its diameter greatly increases and its length correspondingly decreases. This causes the ITS to pull itself out of its stored location over the side window into a straight line between its anchor points. The ITS thereby forms a taut semi-rigid structural member across the window opening.

A sled-to-sled subsystem side impact test methodology has been developed by using two sleds at the WSU Bioengineering Center in order to simulate a car-to-car side impact, particularly in regards to the door velocity profile. Initially this study concentrated on tailoring door pulse to match the inner door velocity profile from FMVSS 214 full-scale dynamic side impact tests. This test device simulates a pulse quite similar to a typical door velocity of a full size car in a dynamic side impact test. Using the newly developed side impact test device three runs with a SID dummy were performed to study the effects of door padding and spacing in a real side impact situation. This paper describes the test methodology to simulate door intrusion velocity profiles in side impact and discusses SID dummy test results for different padding conditions.

The objective of this study is to introduce and assess a computational tool designed to facilitate product development via sensory scores, which serve as a quantifiable representation of human sensory experiences. In the context of designing ride comfort performance, the specialized terminology—either technical or sensory—often served as a barrier to comprehension among the diverse set of specialists constituting the multidisciplinary team. In a previous study by the authors introduced a tool that incorporated a model of sensory performance, utilizing sensory scores as universally comprehensible metrics. However, the tool had yet to be appraised by a genuine cross-functional team. In this study, the tool underwent evaluation through a user-testing process involving twenty-five cross-functional team members engaged in the conceptual design phase at an automotive manufacturing company.

The National Institute for Occupational Safety and Health (NIOSH), in cooperation with the Canadian Forces Health Services Group Headquarters, U.S. Army Tank-Automotive and Armaments Command (TACOM), and the Ministry of Health & Long-Term Care, Ontario (Canada), conducted a test program to evaluate the capability of mobile restraint systems to protect occupants in the patient compartment of an ambulance. This paper focuses on the vehicle chassis behavior and acceleration pulses as seen in each test conducted to support the program. This program consisted of testing one Type I ambulance mounted on a Ford F-350 truck chassis (1994 vintage), and three Type III ambulances mounted on Ford E-350 van chassis (two 1993, and one 1999 vintage). A vehicle-to-vehicle side impact test was conducted using the Type I ambulance with a targeted change in velocity of 27.4 kph (17 mph). A 1984 Chevrolet Sierra 2500 was the impacting vehicle for the side test.

This study aimed to construct driver models for overtaking behavior using long short-term memory (LSTM). During the overtaking maneuver, an ego vehicle changes lanes to the overtaking lane while paying attention to both the preceding vehicle in the travel lane and the following vehicle in the overtaking lane and returns to the travel lane after overtaking the preceding vehicle in the travel lane. This scenario was segregated into four phases in this study: Car-Following, Lane-Change-1, Overtaking, and Lane-Change-2. In the Car-Following phase, the ego vehicle follows the preceding vehicle in the travel lane. Meanwhile, in the Lane-Change-1 phase, the ego vehicle changes from the travel lane to the overtaking lane. Overtaking is the phase in which the ego vehicle in the overtaking lane overtakes the preceding vehicle in the travel lane.

The increasing importance of minimizing drag and the absence of an exhaust system result in battery electric vehicles (BEVs) commonly having a very streamlined underbody. Although this shape of underbody is typically characterized by a low acoustic interference potential, significant flow resonance can be observed for certain vehicle configurations and frequencies below 30 Hz. Since the interior of the vehicle can be excited as a Helmholtz resonator, these low-frequency fluctuations result in reduced comfort for the passengers. As preliminary studies have shown, the flow around the front wheel spoilers significantly influences this flow phenomenon. Flow separation occurs at the front-wheel spoilers and at the front wheels. This leads to the generation of vortices which are growing significantly while being transported downstream with the flow. Even small geometric changes to add-on components on the underbody significantly influence both aerodynamics and aeroacoustics.

An innovative Power Line Carrier (PLC) Communication system for video and digitally signal processed data distribution using the existing DC copper wire is presented. The major contribution consists of a new signal coupler that achieves a stable transmission bandwidth on the DC electrical lines. Several weeks of continuous beta tests achieved video transmission on the trucks +12V wiring (from the back of the truck to the driver's cabinet) and product manufacturing and delivery has started. Benefits include: simplicity of application; ease of implementation; effectiveness with video and data; applicability to all application types; elimination of coax and twisted pair wiring and its maintenance.

Modern heavy vehicles may be equipped with an Advanced Driver Assistance System (ADAS) designed to increase highway safety. Depending on the vehicle or manufacturer, these systems may detect objects in a driver’s blind spot, provide an alert when the ADAS determines that the vehicle is leaving its lane of travel without the use of a turn signal, or notify the driver when certain road signs are detected. ADASs also include adaptive cruise control, which adjusts the vehicle’s set cruise speed to maintain a safe following distance when a slower vehicle is detected ahead of the truck. In addition, the ADAS may have a Collision Mitigation System (CMS) component that is designed to help drivers respond to roadway situations and reduce the severity of crashes. CMSs typically use radar or a combination of radar and optical technologies to detect objects such as vehicles or pedestrians in the vehicle’s path.

Anti-lock brakes have been implemented on tractor-trailer units for several years. However, a fatal accident involving trailer swing indicated that there is some disagreement within the accident reconstruction industry as to what effects trailer anti-lock brake systems have on the stopping performance, dynamic performance/handling of the trailer, and resultant skid marks left on the roadway. Full-scale testing was conducted on a tractor-trailer unit which was equipped with anti-lock brakes on both the tractor and trailer. Full application braking tests were performed from 65-70 mph concurrent with a lane change. Baseline tests were conducted with all anti-lock systems operational, and the tire marks, amount of trailer swing, and stopping distance were recorded. The test was then repeated with the trailer anti-lock brakes disabled.

Lubricant quality impacts performance and durability of heavy-duty off-highway equipment. Accordingly, equipment manufacturers work cooperatively with the petroleum and additive industries to develop performance specifications for lubricants and utilize these specifications in making recommendations for the end user. Currently, a new industry classification is being developed for multipurpose power transmission fluids. This paper discusses this proposed classification and other trends in power transmission lubrication.