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Rear underrun protection device is crucial for rear impact and rear under-running of the passenger vehicles to the heavy duty trucks. Rear underrun protection device design should obey the safety regulative rules and successfully pass several test conditions. The objective and scope of this paper is the constrained optimization of the design of a rear underrun protection device (RUPD) beam of heavy duty trucks for impact loading using correlated CAE and test methodologies. In order to minimize the design iteration phase of the heavy duty truck RUPD, an effective, real-life testing correlated, finite element model have been constructed via RADIOSS software. Later on, Pareto Optimization has been applied to the finite element model, by constructing designed experiments. The best solution has been selected in terms of cost, manufacturing and performance. Finally, real-life verification testing has been applied for the correlation of the optimum solution.

This paper is on the design of a steer-by-wire system for a light commercial vehicle. A hardware-in-the-loop simulation test rig with the actual rack and pinion mechanism of the light commercial vehicle under study was built for this purpose. The steer-by-wire actuator can be placed on either the second pinion, the first pinion or both in the double pinion steering test system used. The hardware and geometry of the steering test rig are identical to the implementation of the steering system in the test vehicle. Unnecessary and expensive road testing is avoided with this approach as most problems are identified and solved in the hardware-in-the-loop simulation phase conducted in the laboratory where the steering subsystem and its controller exist as hardware and the rest of the vehicle exist as a software model running in real time. Hardware-in-the-loop simulation results show the effectiveness of the proposed controller design in tracking desired steering dynamics.

This paper presents the development of a transient active control (TABC) system for the Ford Transit Connect light commercial vehicle using semi active suspensions. The control objective is to improve the ride comfort and road holding together with achieving roll and pitch stability using four semi active suspension dampers, hence called transient active body control. Semi-active control algorithms such as sky-hook, ground-hook and hybrid are applied to each suspension while the roll and pitch stabilizing controllers are designed separately and interfere with the local semi-active controllers through a supervisory control algorithm, if necessary. Simulation and experimental results are presented to demonstrate the effectiveness of the proposed technique.

This paper focuses on experimental and numerical investigations on preload drop of rear axles differential side bearings which occur during tube to carrier pressing operation on the assembly line. The phenomena behind preload decrease during tube fitting operation is revealed via CAE iterations and verified with on site measurement data using strain gauged bearings. It is proven that the level of preload drop during tube pressing operation depends on tube to carrier fitting interference.

This paper represents identification and elimination of differential side bearing failures of a medium duty cycle vehicle. Using instrumented bearings, it is demonstrated that the variation in preload drop during tube pressing operation depends on tube to carrier fitting tolerances. The variability in bearing preload drop is identified and CAE analysis revealing the phenomena behind this issue is conducted. Implementation and verification of corrective actions are also covered within this paper.

Presented here is the cooling system development of Ford Transit vehicle with 200 PS five cylinder engine by Ford Otosan engineers. After 140 PS Ford four cylinders engine, 200 PS engine was developed, completely new and more powerful cooling system was required. CFD studies were carried out to decide about the cooling pack details. UH3D CFD model was developed. Based on given radiator, condenser and fan performance data, engine heat rejection, coolant flow rate, top hose temperature were determined. CAE studies were done for different radiator sizes, different bumper slots and different fan sizes. Based on CFD studies it was decided what to test in the wind tunnel. Vehicle tests were done to verify cooling pack performance.

There is an increasing trend in the worldwide automotive area towards developing hybrid electric vehicles as an intermediate solution to fulfill the new, more stringent pollutant emission level requirements set by governments. Conversion of braking energy into electrical energy stored in the battery through regenerative braking is an important aspect of hybrid electric vehicles that increases their fuel efficiency. This paper presents an electric regenerative power assisted brake algorithm developed to enhance energy efficiency of a front and rear wheel drive parallel hybrid electric commercial vehicle. The commercial vehicle used in this study is a second generation research prototype Ford Transit Parallel Hybrid Electric Van. The existing hydraulic brake system of this van was not altered for reasons of safety and reliability in the case of a problem with regenerative barking.

The crankshaft is the component which transmits dynamical loading from cylinder pressure and inertial loads in engine operating conditions. Because of the crucial importance of its function, crankshaft fatigue life is desired to be higher than the predicted engine operating life. In this study, Puma I5 crankshaft dynamic simulation is performed with multi body dynamics technique. Fatigue safety factors are calculated with the dynamical loadings of engine operating conditions. The effects of single mass and dual mass flywheel on endurance limit are analyzed in this study.

In a Hybrid Electric Vehicle (HEV), the main aim is to decrease the fuel consumption and emissions without significant loss of driving performance. Maximizing Overall Efficiency Strategy (MOES) algorithm, presented here, distributes the power demand among the available paths to the wheels to improve fuel economy. In MOES, the vehicle is considered as a system whose input and output are power capability of consumed fuel and actual power transferred to the road, respectively. The aim of the strategy is to maximize the overall efficiency of the vehicle determined as the ratio of output power to input power. The control algorithm and driver model were prepared within Simulink and used to drive the Carmaker model of the vehicle which is a Ford Transit hybrid electric research prototype van. Simulations were carried out in 3 modes of the vehicle; conventional mode, regenerative braking only mode and full MOES mode to analyze the role of optimization better.

Comfort ride appears as one of the challenging factors in today's competitive automotive sector. Noise level of the vehicle is an effective parameter for the comfort demand of the customer. Oil-pan is the component which transmits structural borne excitations from engine block to air. Improving the NVH performance of the pan by adding beads is a low cost approach and does not increase the mass. Aim of this study is to improve the stiffness of the Puma I5 engine oil pan assembly and to obtain satisfactory improvement in noise levels while keeping the mass of the oil-pan constant.

It is an important problem to estimate the fatigue life of spot welds. There are a number of spot weld models in literature put forward to represent spot welds in finite element models. In this study, five popular spot weld models are compared with each other and experimental results. It is concluded that 9-point contact method is the best one among other models considered in this study based on strain measurements. In terms of fatigue tests, 9-point contact and umbrella models yield better-correlated results than the rigid and elastic beam models.

In this study, a compliant control strategy is developed, which makes the application of position based control strategies practicable for electric power assisted steering systems. In order to do this, an additional virtual degree of freedom is added to the system, which is stimulated by the torque exerted on the steering wheel by the driver and the pinion position. The electro-actuator modeled on the second pinion of the steering gear is then commanded to position the pinion to the virtual system position using a traditional position control strategy. Thus, a compliance behavior is established that can be varied depending on the vehicle states and environmental conditions to improve the vehicle dynamics and safety of the passenger.

In this paper, the optimum linear/nonlinear spring and linear/nonlinear damper force versus displacement and force versus velocity characteristic functions, respectively, are determined using simple lumped parameter models of a quarter car front independent suspension and a half car rear solid axle suspension of a light commercial vehicle. The complexity of a nonlinear function optimization problem is reduced by determining the shape a priori based on typical shapes supplied by the car manufacturer and then scaling it up or down in the optimization process. The vehicle ride and handling responses are investigated considering models of increased complexity. The linear and nonlinear optimized spring characteristics are first obtained using lower complexity lumped parameter models. The commercial vehicle dynamics software Carmaker is then used in the optimization as the higher complexity, more realistic model.

Remanufacturing is a process in which used products are disassembled, and their components are repaired and used in the production of new products. This study investigates the impact of various remanufacturing decisions on Original Equipment Manufacturer (OEM) profitability and market cannibalization in an infinite-horizon production scenario for heavy duty vehicle (HDV) clutches. A discrete event simulation model is developed for benchmarking of different scenarios using various factors and their levels. There are two consumer segments as primary customer and grey customer in the market. Three different end of life (EOL) clutch quality conditions are defined, and three different percentages of clutch collect strategies are defined for all EOL products in the market.

Some of the engine components are connected both to the chassis and to the engine. These parts are subject to vibrational loads coming from the road and the engine. Engine loads are generally considered to be deterministic, whereas the road load is random and conventional methods such as steady state forced frequency analysis, or PSD approach usually focus on engine and road loads separately. Since phase information is lost during PSD conversion, it is not possible to superimpose the results of these analyses without making additional assumptions such as creating random phase data for stress results, which would be a questionable technique. Consequently, these approaches generally result in delivering incomplete information for fatigue evaluation. In this study, both of the engine and road loads are considered simultaneously. Direct transient analysis technique is utilized in order to obtain overall stress values on the parts.