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A road test on semi-trailers is carried out, and accelerations of some characteristic points on the braking system,axles,and truck body is measured,also brake pressure and noise around the support frame is acquired.The measured data was analyzed to determine the causes of the brake noise, and the mechanism of the noise of the drum brake of semi-trailers during low-speed braking was investigated. The following conclusions are obtained: (1) Brake noise of the drum brake of the semi-trailer at low-frequency is generated from vibrations of the brake shoes, axle, and body, and the vibration frequency is close to 2nd natural frequency of the axle. (2) Brake noise is generated from stick-slip motion between the brake shoes and the brake drum, where the relative motion between the brake drum and the brake shoes is changed alternately with sliding and sticking, resulting in sudden changes in acceleration and shock vibration.

This paper details the advancements and outcomes of the NEXTCAR (Next-Generation Energy Technologies for Connected and Automated on-Road Vehicles) program, an initiative led by the Advanced Research Projects Agency-Energy (ARPA-E). The program focusses on harnessing the full potential of Connected and Automated Vehicle (CAV) technologies to develop advanced vehicle dynamic and powertrain control technologies (VD&PT). These technologies have shown the capability to reduce energy consumption by 20% in conventional and hybrid electric cars and trucks at automation levels L1-L3 and by 30% L4 fully autonomous vehicles. Such reductions could lead to significant energy savings across the entire U.S. vehicle fleet.

A variety of structures resonate when they are excited by external forces at, or near, their natural frequencies. This can lead to high deformation which may cause damage to the integrity of the structure. There have been many applications of external devices to dampen the effects of this excitation, such as tuned mass dampers or both semi-active and active dampers, which have been implemented in buildings, bridges, and other large structures. One of the active cancellation methods uses centrifugal forces generated by the rotation of an unbalanced mass. These forces help to counter the external excitation force coming into the structure. This research focuses on active force cancellation using centrifugal forces (CFG) due to mass imbalance and provides a virtual solution to simulate and predict the forces required to cancel external excitation to an automotive structure. This research tries to address the challenges to miniaturize the CFG model for a body-on-frame truck.

The recent progress in camera-based technologies has prompted the development of prototype camera-based video systems, intended to replace conventional passenger vehicle mirrors. Given that a significant number of collisions during lane changes stem from drivers being unaware of nearby vehicles, these camera-based systems offer the potential to enhance safety. By affording drivers a broader field of view, they facilitate the detection of potential conflicts. This project was focused on analyzing naturalistic driving data in support of the Federal Motor Vehicle Safety Standard 111 regulatory endeavors. The goal was to assess the effectiveness and safety compatibility of prototype camera-based side-view systems as potential replacements for traditional side-view mirrors.

Ride comfort is a critical factor to customer perception of vehicle quality as it is related to vehicle experience when driving. It adds value to the product and, consequently, to vehicle brand. It has become a demand not only for passenger unibody vehicles but also to larger segments including mid-size trucks. Ride quality is usually quantified as harshness which is a measure of how the vehicle transmits the road irregularities to the customer at the tactile points such as the steering wheel and seats. Improving harshness requires tuning of different parts including tires, chassis frame/subframe and suspension mounts and bushings. This paper describes the methodology to enhance the harshness performance for a mid-size truck using a full vehicle CAE model. The influence of stiffnesses of body mounts and control arms bushings to harshness response is investigated through sensitivity analysis and the optimal configuration is found.

Abstract The cooperative platoon of multiple trucks with definite proximity has the potential to enhance traffic safety, improve roadway capacity, and reduce fuel consumption of the platoon. To investigate the truck platooning performance in a real-world environment, two Peterbilt class-8 trucks equipped with cooperative truck platooning systems (CTPS) were deployed to conduct the first-of-its-kind on-road commercial trial in Canada. A total of 41 CTPS trips were carried out on Alberta Highway 2 between Calgary and Edmonton during the winter season in 2022, 25 of which were platooning trips with 3 to 5 sec time gaps. The platooning trips were performed at ambient temperatures from −24 to 8°C, and the total truck weights ranged from 16 to 39 tons. The experimental results show that the average time gap error was 0.8 sec for all the platooning trips, and the trips with the commanded time gap of 5 sec generally had the highest variations.

The range of test conditions on the dynamometer shall be sufficient to determine the primary operating characteristics corresponding to the full range of vehicle operations. The characteristics to be determined are: a Torque ratio versus speed ratio and output speed b Input speed versus speed ratio and output speed c Efficiency versus speed ratio and output speed d Capacity factor versus speed ratio and output speed e Input torque versus input speed NOTE: For more information about these characteristics and the design of hydrodynamic drives, refer to “Design Practices: Passenger Car Automatic Transmissions,” SAE Advances in Engineering, AE-18 (Third Ed.) or AE-29 (Fourth Ed.).

Editorial The Level 3 conundrum continues The Navigator The subscriptions are coming for your wallet Kodiak Bearish on Spreading Truck Automation Kodiak Robotics' fifth-generation sensor stack and new SensorPods enhance sensor and GPU performance and improve power efficiency. Making Sense of Next-gen ADAS Sensing Experts at AutoSens 2023 explain how technology is right-setting the industry's driver-assist and autonomy ambitions. Simulation vs. Organizational Inertia The chief technical officer of simulation giant VI-grade says that even as it offers a wide range of solutions, some companies are slow to believe in the proven reductions in development time and cost. Self-driving Supercar! This year's iteration of Italy's classic-car-oriented Mille Miglia race showcased an audacious nod to the future: an autonomous high-performance Maserati.

Abstract A rear underrun protection device (RUPD) plays a fundamental role in reducing the risk of running a small car beneath the rear or the side of a heavy truck because of the difference in structure heights in the event of a vehicle collision. Even in cars with five-star safety ratings, crashing into a truck with poorly designed RUPD results in a passenger compartment intrusion (PCI) more than the maximum allowable limit as per the United States (US) American National Highway Traffic Safety Administration (NHTSA) standards Federal Motor Vehicle Safety Standard (FMVSS). In this article, mild steel was used to fabricate the new designs of RUPD. The design was analyzed using finite element (FE) analysis LS-DYNA software. Simulations of a Toyota Yaris 2010 and Ford Taurus 2001 were performed at a constant speed of 63 km/h at the time of impact. The ability to prevent severe injuries in a collision with the rear side of the truck was estimated to optimize the underrun design.

cellcentric – a joint venture of Daimler Truck AG and the Volvo Group AB formed in 2021 - develops, produces and commercializes fuel-cell systems for use in heavy-duty trucks and other applications. Its ambition is to become a leading global manufacturer of fuel-cells, and thus help the world take a major step towards climate-neutral and sustainable transportation by 2050. In this presentation, Lars Johansson, COO of cellcentric, will introduce into the fuel cell technology and leads through the company’s journey from the first prototypes to the planned mass production.

There is potential to reduce GHG emissions in the HDV sector through different powertrain options (electric batteries, fuel cell batteries, and combustion engines), and different fuel or energy choices (hydrogen, biofuels, natural gas). The climate impacts of these technologies and fuels vary over the lifetime of the vehicle model. From extracting and processing raw materials to operation and maintenance, some powertrain options are more energy intensive to build than their counterparts, and some fuel sources can produce higher emissions during their production or use. The study uses a life-cycle assessment to analyze the options to allow policymakers and manufacturing companies to compare which powertrain and fuel options provide the largest GHG emissions reductions.

Electric trucks that use fuel cells to generate on-board power are seen as the cornerstone of zero-carbon, zero-emission long-haul heavy-duty transportation. Modularization of fuel cell stacks, components and systems is critical for rapid market entry and lower total cost of ownership. To achieve this, efficient development processes must be utilized to handle the large variety of applications and use cases with reduced engineering effort. The goals can be achieved with model-based development across the entire development chain. This publication presents such a holistic model-based process that extends from the fuel cell powertrain level through the system level to the component level. This process is closely interlinked to the thermal integration, the function development of the hybrid system as well as the fuel cell system of the vehicle via the use of model-in-the-loop approaches.

Presenting the Volvo transition development work towards carbon neutral products, focused on fuel cell electric vehicle development. Discussing and reflecting on the growth of hydrogen infrastructure and hydrogen storage. Exemplifying with development examples, challenges as well as need of firm standards, policies and economic stability.

The current decade is seeing rapid changes in heavy duty powertrains. All manufacturers at IAA were proposing solutions that support a carbon neutral future. Battery Electric (BEV) or hydrogen either in the form Fuel Cell (FCEV) or Internal Combustion Engines (H2-ICE) are being seen as the most exciting options currently. This presentation focuses in on emissions control of H2-ICE systems. Emissions control of H2-ICE requires close consideration of current and future legislation, as well as meeting new and unique challenges to deliver a sustainable zero carbon solution that the planet requires. H2-ICE SI engines can operate as stoichiometric or lean burn, the direction of emissions control can be chosen based on this. System components need to consider other factors such as possible H2 embrittlement, oil bypass, other legislative criteria emissions, global warming potential (GWP) as well as higher levels of water in the exhaust from H2 combustion.

The Euro 7 emission legislation proposal demands for more advanced system designs as well as technology improvements on both engine and catalyst side. Experience from full system programs show that there is potential to meet legislation with system based on different catalyst technologies. The selection of V- or Cu-based main technology will be discussed as this dictate some of the system boundary conditions. Recent developments of the different catalyst and filter coating technologies will be reviewed and their improved performance and durability will help widen the system boundaries and meet Euro 7.