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An experiment is carried out to measure creep groan of a drum brake located in a trailer axle of a truck. The noise nearby the drum brake and accelerations on brake shoes, axle and trailer frame are collected to analyze the occurring conditions and characteristics of the creep groan. A multi-body dynamics model with 1/4 trailer chassis structures is established for analyzing brake component vibrations that generates the creep groan. In the model, the contact force between brake cam and brake shoes, the contact friction characteristics between brake linings and inner circular surface of brake drum, and the properties of chassis structure are included. Dynamic responses of brake shoes, axle and trailer frame during the braking process are estimated using the established model and the responses are compared with the measured results, which validate the model.

This SAE Standard applies to all forestry machines exposed to the hazard of objects penetrating the front of the operator station (other than the roof). This would include:

The design and analysis of the roll cage for the ATV car are the subjects of this report. The roll cage is one of the key elements of an ATV car. It is the primary component of an ATV, on which the engine, steering, and gearbox are mounted. The vehicle's sprung mass is beneath the roll cage. The initiation of cracks and the deformation of the vehicle are caused by forces acting on it from various directions. Stresses are consequently produced. FEA of the roll cage is used in this paper in an effort to identify these areas. We have performed torsional analysis as well as front, rear, side impact, and rollover crash analyses. These analyses were all completed using ANSYS Workbench 2020 R1. The design process complies with all guidelines outlined in the SAE rule book of E-Baja.

This SAE Recommended Practice identifies the minimum truck tractor electrical power output of the stop lamp and ABS (antilock brake system) circuits measured at the primary SAE J560 tractor trailer interface connector(s).

The phenomenon of liquid transfer in the liquid tank of the semi-trailer vehicle for transporting dangerous cargo (SVTDC) during braking is analyzed and the relevant mathematical model is established. The braking dynamic model of the SVTDC considering the liquid sloshing in the tank is established, and the model is verified based on the co-simulation method. Based on the typical conditions, the braking deceleration and axle load calculation functions of the model are simulated and analyzed, and the application prospect of the model in the development of driving automation control strategy is discussed.

This SAE Recommended Practice defines a method for implementing a bidirectional, serial communications link over the vehicle power supply line among modules containing microcomputers. This document defines those parameters of the serial link that relate primarily to hardware and software compatibility such as interface requirements, system protocol, and message format that pertain to Power Line Communications (PLC) between Tractors and Trailers. This document defines a method of activating the trailer ABS Indicator Lamp that is located in the tractor.

Abstract Parking an articulated vehicle is a challenging task that requires skill, experience, and visibility from the driver. An automatic parking system for articulated vehicles can make this task easier and more efficient. This article proposes a novel method that finds an optimal path and controls the vehicle with an innovative method while considering its kinematics and environmental constraints and attempts to mathematically explain the behavior of a driver who can perform a complex scenario, called the articulated vehicle park maneuver, without falling into the jackknifing phenomena. In other words, the proposed method models how drivers park articulated vehicles in difficult situations, using different sub-scenarios and mathematical models.

Brazil is significant grain (soy, corn, beans and rice) producer in the planet and the road transportation is needed even when rail and maritime mode is used. There are opportunities to improve the grain road transportation efficiency. This paper presents one opportunity which is the aerodynamic drag reduction and therefore the fuel and energy consumption reduction on grain road transportation. This paper will discuss some alternatives to reduce aerodynamic drag on such application considering Brazilian market regulation which has a low limit for front axle load (lower than European regulation for instance) and limit the total composition length. As an example of some alternatives to reduce drag there is the frontal area reduction and trailer to cab gap reduction. Some of those alternatives were implemented on a concept truck briefly presented on this paper, which was tested on a real application, this paper will illustrate some of those alternatives implemented.

The measurement of the cargo weight on semi-trailer trucks is required to several stakeholders in the logistics market, for this information can reduce expenses on vehicle maintenance, risk for load traffic fines and ensures safer driving of the vehicle. The state-of-the-art on on-board weighing systems of semi-trailers with leaf spring suspension adopt several techniques to estimate the load: solutions based on load cells, vibrating-wires force transducers or strain gauges on the chassis, on the suspension springs or on the axles of the vehicle. In this work, a new system based on hall effect sensor was developed and tested for measurement of the axle load in semi-trailers through the linear movement that occurs between the trailer axle and its chassis. This solution has low sensitivity to environmental phenomena not caused by human intervention, such as humidity or temperature variations.

Motor grader is self-propelled, versatile machine widely used for road construction and maintenance in mining and construction applications. It required working in rugged terrain with uneven and slippery surfaces. Probability of rollover in motor grader is more due to the vehicle profile and high centre of gravity. In light of the above, Roll over Protective Structure (ROPS) is essential to safe guard the operator from any fatal injuries / life during the operation of the equipment at different terrain conditions. Considering DGMS (Directorate of General Mines and safety) requirements, a rugged two post Rollover Protective Structure (ROPS) was designed as per ISO 3471 criteria for ROPS and Falling object Protection Structure (FOPS) as per ISO 3449 Material selection for ROPS and FOPS is one of significant factor in design process by meeting the design criteria. It should have dual characteristic, firstly, it is expected to tough enough to withstand sudden impact forces.

Abstract Articulated vehicles form an important part of our society for the transport of goods. Compared to rigid trucks, tractor-trailer combinations can transport huge quantities of load without increasing the axle load. The fifth wheel (FW) acts as a bridge between the tractor and trailer, which can be moved within the range to achieve rated front and rear axle loads. When the FW is moved front, it adversely affects the cab dynamics and cab suspension forces. Compared to the cab pitch and roll, yaw motion increases drastically. The current study tries to address this issue by providing reaction rod links in the rear cab suspension. In this study, a 4×2 tractor with a three-axle semitrailer is considered by keeping the FW at its frontmost position, which is the worst-case scenario for a cab. Three different cases of reaction rod arrangement and its influence on cab dynamics are studied in comparison with a model without reaction rods.

This paper provides a simulation analysis of a novel interconnected roll stability control (RSC) system for improving the roll stability of semitrucks with double trailers. Different from conventional RSC systems where each trailer’s RSC module operates independently, the studied interconnected RSC system allows the two trailers’ RSC systems to communicate with each other. As such, if one trailer’s RSC activates, the other one is also activated to assist in further scrubbing speed or intervening sooner. Simulations are performed using a multi-body vehicle dynamics model that is developed in TruckSim® and coupled with the RSC model established in Simulink®. The dynamic model is validated using track test data. The simulation results for a ramp steer maneuver (RSM) and sine-with-dwell (SWD) maneuver indicate that the proposed RSC system reduces lateral acceleration and rollover index for both trailers, decreasing the likelihood of wheel tip-up and vehicle rollover.

This article presents an autonomous steering control scheme for articulated heavy vehicles (AHVs). Despite economic and environmental benefits in freight transportation, lateral stability is always a concern for AHVs in high-speed highway operations due to their multi-unit vehicle structures, and high centers of gravity (CGs). In addition, North American harsh winter weather makes the lateral stability even more challenging. AHVs often experience amplified lateral motions of trailing vehicle units in high-speed evasive maneuvers. AHVs represent a 7.5 times higher risk than passenger cars in highway operation. Human driver errors cause about 94% of traffic collisions. However, little attention has been paid to autonomous steering control of AHVs.

Autonomous truck and trailer configurations face challenges when operating in reverse due to the lack of sensing on the trailer. It is anticipated that sensor packages will be installed on existing trailers to extend autonomous operations while operating in reverse in uncontrolled environments, like a customer's loading dock. Power Line Communication (PLC) between the trailer and the tractor cannot support high bandwidth and low latency communication. This paper explores the impact of using Ethernet or a wireless medium for commercial trailer-tractor communication on the lifecycle and operation of trailer electronic control units (ECUs) from a Systems Engineering perspective to address system requirements, integration, and security. Additionally, content-based and host-based networking approaches for in-vehicle communication, such as Named Data Networking (NDN) and IP-based networking are compared.

Road vehicles have been shown to experience measurable changes in aerodynamic performance when travelling in everyday safe-distance driving conditions, with a major contributor being the lower effective wind speed associated with the wakes from forward vehicles. Using a novel traffic-wake-generator system, a comprehensive test program was undertaken to examine the influence of traffic wakes on the aerodynamic performance of heavy-duty vehicles (HDVs). The experiments were conducted in a large wind tunnel with four primary variants of a high-fidelity 30%-scale tractor-trailer model. Three high-roof-tractor models (conventional North-American sleeper-cab and day-cab, and a zero-emissions-cab style) paired with a standard dry-van trailer were tested, along with a low-roof day-cab tractor paired with a flat-bed trailer.

This study focused on occupant responses in very large pickup trucks in rollovers and was conducted in three phases. Phase 1 - Field data analysis: In a prior study [9], 1998 to 2020 FARS data were analyzed; Pickup truck drivers with fatality were 7.4 kg heavier and 4.6 cm taller than passenger car drivers. Most pickup truck drivers were males. Phase 1 extended the study by focusing on the drivers of very large pickup trucks. The size of 1999-2016 Ford F-250 and F-350 drivers involved in fatal crashes was analyzed by age and sex. More than 90% of drivers were males. The average male driver was 179.5 ± 7.5 cm tall and weighed 89.6 ± 18.4 kg. Phase 2 – Surrogate study: Twenty-nine male surrogates were selected to represent the average size of male drivers of F-250 and F-350s involved in fatal crashes. On average, the volunteers weighed 88.6 ± 5.2 kg and were 180.0 ± 3.2 cm tall with a 95.2 ± 2.2 cm seated height.

This paper presents the development of a validation criteria method for designing of spring brackets, wear pads and equalizers of a leaf spring suspension of a semi-trailer from the perspective of durability and peak loads. The method consisted of the application of a finite element model from strain data collected in the application test. The results obtained in the components during the trailer’s operation were converted into load through calibration curves. The stress-life method was adopted, correcting the mean stress by the Goodman criterion and with the calculation of accumulated damage using Palmgren-Miner with cycle counting by rainflow in the structures during the data acquisition path. The relation between damage accumulation and the life expectancy of the components, defined in a specific distance (mileage) was established. Basquin´s equation was also used.