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Optimization of heavy materials like steel, in order to create a lighter vehicle, it is a major goal among most automakers, since heavy vehicles simply cannot compete with a lightweight model's fuel economy. Thinking this way, this paper shows a case study where the Size Optimization technique is applied to a front floor reinforcement. The reinforcement is used by two different vehicles, a subcompact and a crossover Sport Utility Vehicle (SUV), increasing the problem complexity. The Size Optimization technique is supported by Finite Element Method (FEM) tools. FEM in Computer Aided Engineering (CAE) is a numerical method for solving engineering problems, and its use can help to optimize prototype utilization and physical testing.

The stabilizer bar attachments problem can not be simply analyzed by using linear FEA methodology. The large deformation in the bushing, the elastic-plastic material property in the bushing retainer bracket, and the contact between different parts all add complexity to the problem and result in the need for an analysis method using a non-linear code, such as ABAQUS. The material properties of the bushing were experimentally determined and applied to the CAE model. It was found that using strains to estimate the fatigue life was more accurate and reliable than using stress. Many modeling techniques used in this analysis were able to improve analysis efficiency.

Considering that the most part of commercial vehicles are equipped with air brakes it is very important assure specific technical requirements for air brake system and its components. In addition, the effects of brake system failure are more critical for commercial vehicles which require more attention on their requirements details. Historically, the development of air brakes technology started on North America and Europe and consequently two strong and distinct resolutions were structured: FMVSS 121 and ECE R.13, respectively. For passenger cars were developed the ECER.13H to harmonize North American and European resolutions. However, for commercial vehicles regional applications, culture and implementation time must be considered. These commercial vehicles peculiarities must be understood and their specific requirements harmonized to attend the global marketing growth.

The development costs that new design requires are subject to everyday discussions and saving opportunities are mandatory. Using CAE to predict design changes can avoid excessive costs with prototypes parts, considering the high reliability those current mathematical models can provide. This paper presents the methodology used during the development of a parabolic leaf spring for the rear suspension of a commercial truck, considering mainly the parabolic profiles and stress distribution on the leaves, calculated using CAE software (ANSYS) and experimental tests to measure the actual stress on each leaf, certifying the correlation between computational calculations and real stress on the parts during bench and vehicle evaluations.

Characterizing or reconstructing incidents ranging from light to heavy crashes is one of the enablers for mobility solutions for fleet management, car-sharing, ride-hailing, insurance etc. While crashes involving airbag deployment are noticeable, light crashes without airbag deployment can be hidden and most drivers do not report these incidents. In this paper, we are using vehicle responses together with a dynamics model to trace back if abnormal forces have been applied to a vehicle so as to detect light crashes. The crash location around the perimeter of the vehicle, the direction of the crash force, and the severity of the crashes are all determined in real-time based on on-board sensor measurements which has further application in accident reconstruction. All of this information will be integrated to a feature called “Incident Report”, which enable reporting of minor accidents to the relevant entities such as insurance agencies, fleet managements, etc.

In order to optimize the development of bolted joints used to components attachments in the Sidemember of commercial vehicles, the joints development has become relevant to better definition of the fasteners size, eliminating overweight and avoiding under or super-sized. This paper presents a development sequential approach of bolted joints applied on commercial vehicles ensuring the correct specifications usage of the fasteners and the joint to keep their clamp force. The evaluations were conducted based on theoretical and practical aspects applied on products and in the definition of all elements contained in a joint. The calculation methodology was developed based on standardized bolts and forces generated through the reactions of the components required for each vehicle family.

In this paper, a simplified and systematic approach to integrate reliability and durability aspects in design process is presented. A six step process is explained with the help of examples. Two alternatives for gathering means and standard deviations for key parameters are discussed. First a DOE approach based on orthogonal arrays is presented. Second approach is based on Taylor Series expansion. An example of beam design is solved with both of these approaches. The Second example also considers the degradation with time in service.

The growing competition of the automotive market makes more and more necessary the reduction of development time and consequently, the increase of the capacity to quickly respond to the launching of the competitors. One of the most costly phases on the vehicle development process is the field durability test, both in function of the number of prototypes employed and the time needed to its execution. More and more diffused, the fatigue life prediction methods have played an important part in the durability analysis via CAE. Nevertheless, in order they can be reliable and really being able to reduce the development time and cost, they need to be provided with load cases that can accurately represent the field durability tests. This work presents a CAE approach used for light trucks in order to get a reasonable understanding of component durability behavior due to payload increase. In general, road load data is not available for a new payload condition.

Recent accomplishments, made possible by advances in manufacturing and material technology, have led to the development of a one-piece stamped I-Beam axle with ball joints as a replacemet to the forged axle with king pin design. The new stamped I-Beam axle brings with it a number of improvements to Ford's Twin I-Beam suspension system. This paper describes the objectives, improvements, evolution of the design, testing, and the manufacturing process for this latest suspension system improvement on Ford light trucks.

Ford's continued effort to improve fuel economy in automotive applications has emphasized the need for lightweight components that retain all the toughness associated with Ford truck vehicle characteristics. The application of an impact extrusion process to wheel design and manufacture, for Ford Aerostar, provides strength, performance and style more efficiently than other traditional processes. It results in a valuable 33% weight saving over comparable HSLA steel wheels, and provides the customer with uncompromised value. The Ford Aerostar Impact Extruded Aluminum Wheel was designed to be of one-piece construction, manufactured from a less than 1″ thick aluminum wafer-shaped blank. The process permits manufacture in half the steps of a conventional stamped steel wheel, and eliminates extensive machining required with forged or cast aluminum wheels.

Automotive cruise control systems are used to automatically maintain the speed of a vehicle at a desired speed set-point. It has been shown that fuel economy while in cruise control can be improved using advanced control methods. The objective of this paper is to validate an Adaptive Nonlinear Model Predictive Controller (ANLMPC) implemented in a vehicle equiped with standard production Powertrain Control Module (PCM). Application and analysis of Model Predictive Control utilizing road grade preview information has been reported by many authors, namely for commercial vehicles. The authors reported simulations and application of linear and nonlinear MPC based on models with fixed parameters, which may lead to inaccurate results in the real world driving conditions. The significant noise factors are namely vehicle mass, actual weather conditions, fuel type, etc.

This is an extension of simple fuel consumption modeling toward HEV. Previous work showed that in urban driving the overhead of running an ICEV engine can use as much fuel as the traction work. The bidirectional character and high efficiency of electric motors enables HEVs to run as a BEV at negative and low traction powers, with no net input from the small battery. The ICE provides the net work at higher traction powers where it is most efficient. Whereas the network reduction is the total negative work times the system round-trip efficiency, the reduction in engine running time requires knowledge of the distribution of traction power levels. The traction power histogram, and the work histogram derived from it, provide the required drive cycle description. The traction power is normalized by vehicle mass, so that the drive trace component becomes invariant, and the road load component nearly invariant to vehicle mass.

Do older light trucks, often with second (and subsequent) owners, present a higher risk to either their own occupants or to other road users? And is the safety record for newer trucks better or worse than the record for their older counterparts? To answer these questions, fatalities in crashes involving at least one light truck were examined using the Fatal Analysis Reporting System (FARS). Fatality rates for both occupants of the light truck and for other road users (occupants of other motor vehicles, pedestrians, etc.) in these crashes were computed, based both on the number of registered vehicles and on the vehicle miles of travel. Two trends in these fatality rates are observed. First, as light trucks age, a consistent decline is found in risk both to their own occupants and to other road users. Second, a distinct decrease is found in road user risk for newer light trucks compared to older light trucks when they were new, both for their own occupants and for other road users.

Analysis of road accidents has shown that an important portion of fatal crashes involving Commercial Vehicles are caused by rollovers. ESC systems in Commercial Vehicles can reduce rollovers, severe understeer or oversteer conditions and minimize occurrences of jackknifing events. Several studies have estimated that this positive effect of ESC on road safety is substantial. In Europe, Electronic Stability Control (ESC) is expected to prevent by far the most fatalities and injuries: about 3,000 fatalities (-14%), and about 50,000 injuries (-6%) per year. In Europe, Electronic Stability Control Systems is mandatory for all vehicles (since Nov. 1st, 2011 for new types of vehicle and Nov. 1st, 2014 for all new vehicles), including Commercial Vehicles, Buses, Trucks and Trailers.

Fuel power consumption for light duty vehicles has previously been shown to be proportional to vehicle traction power, with an offset for overhead and accessory losses. This allows the fuel consumption for an individual powertrain to be projected across different vehicles, missions, and drive cycles. This work applies the power-based model to commercial vehicles and demonstrates its usefulness for projecting fuel consumption on both regulatory and customer use cycles. The ability to project fuel consumption to different missions is particularly useful for commercial vehicles, as they are used in a wide range of applications and with customized designs. Specific cases are investigated for Light and Medium Heavy- Duty work trucks. The average power required by a vehicle to drive the regulatory cycles varies by nearly a factor 10 between the Class 4 vehicle on the ARB Transient cycle and the loaded Class 7 vehicle at 65 mph on grade.

It is very important and unquestionable that we need to have a clear technical requirement for Air Brake Systems and its components, since it is one of most important regarding safety. Looking to heavy commercial vehicles and possible air brake system failures, everything becomes clearly to pay total attention for these normative and regulatory requirements. Historically, the development of Brakes technology has started on EUA and Europe and consequently two strong and distinct requirements were structured: FMVSS 121 and ECE-R13. From decades people are trying to harmonize these requirements and for passenger cars, the evolution was faster. However, for commercial vehicles there are more peculiarities considering regional applications and some of them cultural and implementation time. As globally market is growing so fast as well new markets around the world, become fundamental the clearly understanding of these similarities, variants, peculiarities and correlated requirements.

The objective of this paper is to demonstrate that frequency domain methods for calculating structural response and fatigue damage can be more widely applicable than previously thought. This will be demonstrated by comparing results of time domain vs. frequency domain approaches for a series of fatigue/durability problems with increasing complexity. These problems involve both static and dynamic behavior. Also, both single input and multiple correlated inputs are considered. And most important of all, a variety of non-stationary loading types have been used. All of the example problems investigated are typically found in the automotive industry, with measured loads from the field or from the proving ground.

Conventional cruise control systems in automotive applications are usually designed to maintain the constant speed of the vehicle based on the desired set-point. It has been shown that fuel economy while in cruise control can be improved using advanced control methods namely adopting the Model Predictive Control (MPC) technology utilizing the road grade preview information and allowance of the vehicle speed variation. This paper is focused on the extension of the Adaptive Nonlinear Model Predictive Controller (ANLMPC) reported earlier by application to the trailer tow use-case. As the connected trailer changes the aerodynamic drag and the overall vehicle mass, it may lead to the undesired downshifts for the conventional cruise controller introducing the fuel economy losses. In this work, the ANLMPC concept is extended to avoid downshifts by translating the downshift conditions to the constraints of the underlying optimization problem to be solved.

In order to evaluate the THOR-50M as a front impact Anthropomorphic Test Device (ATD) for vehicle safety design, the ATD was compared to the H3-50M in matching vehicle crash tests for 20 unique vehicle models from 2 vehicle manufacturers. For the belted driver condition, a total of fifty-four crash tests were investigated in the 56.3 km/h (35 mph) front rigid barrier impact condition. Four more tests were compared for the unbelted driver and right front passenger at 40.2 km/h (25 mph) in the flat frontal and 30-degree right oblique rigid barrier impact conditions. The two ATDs were also evaluated for their ability to predict injury risk by comparing their fleet average injury risk to Crash Investigation Sampling System (CISS) accident data for similar conditions. The differences in seating position and their effect on ATD responses were also investigated.

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.