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SAE Off-Highway Engineering 2004-10-01

Beyond batteries the reinvention of a 100-year old electrical energy-storage device could transform heavy-duty hybrid drive systems. Pumping down the volume The design evolution of low-noise spur and helical gear pumps. Tackling Tier 3 Both Cummins and Caterpillar choose the in-cylinder approach to reducing emissions. The telematics fix Diagnostics may be the key to keeping telematics viable and affordable. Complete and intelligent systems SAE 100 Future look: The future of mobile hydraulics can be seen today. Modern mobile hydraulics of today and tomorrow consists of complete system solutions with integrated electronics, which make off-highway machinery more efficient and, at the same time, reduce life-cycle costs. The next step in hydraulics and electronics SAE 100 Future Look: As we celebrate 100 years of SAE's contributions to our industry, it seems very appropriate to look forward at the next few years and assess where we will be.
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Wiley SAE MOBILUS® eBook Package

Committed to being the primary source for aerospace and ground vehicle engineering resources, SAE International has added the full compilation of our Wiley eBook collections to the SAE MOBILUS® technical resource platform. Purchasable as an annual subscription and containing the titles from the Wiley Aerospace Collection, the Wiley Automotive Collection, the Wiley Computer Systems Collection, and the Wiley Cyber Security Collection.

Hydraulic Hybrid System Optimization Using Design For Six Sigma

There are several variables to consider when specifying a hydraulic hybrid system in a commercial vehicle. Parameters which can be controlled include various component sizes and some hybrid system calibration parameters. Presenter Paul Schwark, Bosch Rexroth AG
Technical Paper

Powertrain Mounting Development Based on Computational Simulation and Experimental Verification Method

This paper presents a method applied in the development of an optimized transmission rubber mount of a midsize Diesel pickup. The focus of this optimization were to improve the vibration insulation and consequently improve the NVH (Noise and Vibration Harshness) quality of the vehicle. The paper describes the basic mounting design and manufacturing constrains, the simulation modeling basis, inputs required to perform the computational simulation, the experimental method used to extract the center of gravity and rotational inertia of the powertrain and a general mounting tuning strategy. The mounting dynamic simulation results for the optimized version is also presented compared to the original one. In order to quantify the noise and vibration improvements, the internal noise and vibration transmissibility levels were measured and compared in percentile reduction basis to current vehicle levels
Technical Paper

A Theoretical Study on Front Steering Angle Compensation Control for Commercial Vehicles

This study investigates a control strategy using the front steering angle control to improve the handling and stability of heavy-duty vehicles as a possible substitute for four-wheel steering (4WS) system. The effective steering input is regulated through the state feedback computed by the optimal control theory suggested in this research, to adapt the closed system to the changes of some factors depending on running situations, such as velocity and center of gravity. Direct moment control with a simple auto-tuning proportion controller is also integrated in the compensation system, wherein yaw moment and roll moment are applied to decrease side slip angle and roll angle respectively. A double-cost-function LQR methodology (DLQR) is developed to compute the value of the front steering angle compensation.
Technical Paper

The Daewoo K series heavy-duty diesel engine~Design feature

DHI has developed completely new six-cylinder K series engine for heavy-duty commercial vehicle as well as other industrial equipment. And DHI will produce it in the new kunsan engine plant. The main development targets were low emissions, excellent fuel economy, longer durability and minimum maintenance. For fulfilling these targets, high-pressure electronic unit injector system (EUI) with 4 valve and overhead camshaft (OHC), symmetrically structured cylinder block with very stiffened cylinder liner and bed plate, decompression engine brake system were adopted. During the design stage, CAE technology played very important role, through detail analysis and optimization. The K series engine achieved low exhaust gaseous emission level of Euro 3 as well as good fuel consumption, noise level lower than 96 dB(A), and major overhaul period longer than 1.5 million km.
Technical Paper

Accelerated Product Development Using Dynamic Simulation and RPC Test

This paper describes an integrated dynamic simulation and RPC (Remote Parameter Control) shaker test approach that accelerates product development of structural components. The simulation is based on the principle of random vibration and is used for optimizing the design in the early stages of the design process. Once the prototypes are built, RPC shaker test is used to verify the structural integrity of the optimized designs. The benefits of this integrated approach are demonstrated using a tractor seat development example. The simulation was able to pin-point potential failure locations and estimate the fatigue life. The design was optimized using only one design iteration.
Technical Paper

CRASH-97 - Refinement of the Trajectory Solution Procedure

The trajectory solution procedures of the original CRASH program included both the SPIN routine and an exploratory trajectory simulation option to approximate and refine the linear and angular velocities at separation. The resulting separation speeds were then used to determine the impact speeds by means of application of the principle of conservation of linear momentum. This paper presents a detailed review of the logic, rationale and limitations of the trajectory solution procedures of the original CRASH program and discusses a number of refinements including: incorporation of the principle of conservation of angular momentum, approximations of the effects of changes during collision in the positions and orientations of the two vehicles and of the effects of external forces and moments that act on the two-body system during the collision, and adaptations of optimization techniques for error reduction and convergence in iterative solutions.
Technical Paper

Ecologically Oriented Agricultural Machinery Development

During the last few years, industry has come to face the demand of optimizing the ecological compatibility of its technical products. Especially the agricultural machinery branch is to develop ecologically compatible machines and facilities as these are used for work in ecologically sensitive areas. This paper will present the practical experiences of optimizing agricultural machines' ecological compatibility; it will also show a method designed for ecologically oriented agricultural machines' development in small and medium sized enterprises, based on these experiences.
Technical Paper

Diaphragm Chamber Fuel Flow Transducers for On-Board Computers of Mobile Agricultural Machines

The problem of fuel consumption decrease in agricultural machinery may be addressed in several ways. One is to equip mobile agricultural machines (tractors, harvesters, sprayers, fertilizer spreaders, etc.) with on-board computers (BC) capable to measure the fuel flow rate, in particular, which will allow to decrease fuel consumption by these machines due to timely control of the technical conditions of the engine and optimization of the machine operation modes from the point of view of fuel consumption. The article describes a family of diaphragm chamber fuel flow transducers (FFT) for on-board computers of mobile agricultural machines, gives their technical characteristics and laboratory and field test results, and recommendations on connecting them to engines of various power specifications.
Technical Paper

Weld Process Modeling and It's Importance in a Manufacturing Environment

An important emerging technical area is computer-based modeling of the various manufacturing processes that are used in many diverse industries. These models are used to optimize manufacturing techniques to reduce fabrication costs and improve the service performance. One manufacturing process important in steel fabrication is welding. It can be a useful tool to aid in reducing fabrication costs and service durability by optimizing the weld process and is the subject of this paper.
Technical Paper

Optimization Applications for Cast Structures

Cast structures offer significant potential for weight reduction by applying numerical optimization methods. However, optimization techniques have been rarely used by industry in these applications because of either the large computational resources required or the extensive time required to set up the optimizations. Improvements in topological optimization and faster computers have overcome some of these problems. This paper shows some examples of recent optimization studies as applied to cast structures. Topological optimization studies are performed using ANSYS finite element software. Sizing optimization studies were performed with MSC/NASTRAN software. These studies have shown that optimization can be effectively applied to solid structures, assuming that the critical loads can be modeled with linear analyses.
Technical Paper

Optimizing the Control Signal Applied to a Hydraulic Proportional Valve

Many existing electronic controls used in hydraulic systems utilize a microcontroller with associated electronic drive buffer and multiple closed loop feedback paths. One of the common feedback paths is through sensing the electrical current supplied to the solenoid for the proportional valve. Use of pulse-width-modulation (PWM) is typically utilized to minimize power dissipation in the electronic drive buffer and to facilitate integration with the microcontroller.
Technical Paper

Impact Project: Searching for Solution to the Underride Problem

Rear underride crashes kill thousands of people yearly worldwide. Underride guards did not follow the progress achieved by the automotive safety technology. Searching for solutions to this problem, two new guards have been designed and three crash tests carried out. A new articulated, an energy absorbing conceptual guard and a guard constructed according to the European (ECE-R58) regulation were tested. Both the new guards could avoid underride, the ECE-R58 one could not. The tests pointed out that the new articulated guard could be used after a few modifications and the conceptual one needs further optimization to become commercially feasible.
Technical Paper

Northeast Electric Bus Demonstration Project: Cabin Thermal Management

The Northeast suffers from levels of ozone and fine paniculate mater which threaten public health. While diesel powered buses can reduce reliance on personal automobiles, they are a significant source of the emissions which make up these air pollution problems. Electric powered transportation can make a contribution to meeting society's desires for clean air and transportation services. However, for this technology to be acceptable to transit operators and the public, it must demonstrate that it is not only clean, but can provide a level of service competitive with conventional technology, while satisfying riders' needs and comfort. To this end, the Northeast Advanced Vehicle Consortium (NAVC) working with transit operators in the northeast, Advanced Vehicle Systems, Inc (AVS), Solectria Corp., and EVermont has undertaken a project to redesign a 22-foot electric shuttle bus. In total, five buses will be built and operated at three Northeast locations.
Technical Paper

Suspension and Bushing Parameter Optimization for Vibration Reduction in a Heavy Vehicle Cab

A dynamic model of a truck was developed using a multi-body system (MBS) analysis software. Through this model the vibrations in the cab induced by the vehicle ride on a test track with known obstacles was simulated. Values of stiffness and damping of vehicle and cab suspensions were varied in order to give a higher comprehension of their influence in the vibration level of the cab.
Technical Paper

Optimization of Gearbox Ratios Using Techniques for Dynamic Systems

The objective of this paper is to demonstrate a possibility of optimizing the fixed gear ratios of an automatic transmission by using a special modeling and simulation technique. It is a problem to design the set of ratios in general, and especially for transient driving situations. Sometimes there is a lack of systematic methods to optimize dynamic systems, and particularly vehicle powertrain systems, which is the focus of this paper. The techniques used involve a dynamic engine model and a refined gearbox model. To give each set of ratios a fair judgement, the gearbox control system is calibrated for each new set. The influence of a set of ratios on the vehicle acceleration performance and fuel economy in a given driving cycle is evaluated against an optimization criterion. Calibration of the gearbox control system is performed with stationary analysis. This is the most suitable way with respect to the input signals of gearbox control systems of today.
Technical Paper

Design and Development of New Spicer S400-S Tandem Axle

The design objective of the Spicer S400-S axle program was to develop a light weight, lower torsional vibration, long life tandem drive axle for the heavy truck industry. This was accomplished with the incorporation of a number of new product features and technical advancements, both in design and manufacturing. These include: reduced standouts for improved interaxle driveline angles use of finite element analysis fixed pinion mounting optimization of lube flow and direction of lubrication optimized gear design for improved strength and noise reduction. This paper focuses on these features and also on the development process for the axle, including the use of simultaneous engineering. Utilizing simultaneous engineering, the S400-S was developed from concept to full production in fifteen months.
Technical Paper

Torsional Powertrain Vibration on Heavily Overloaded Vehicle at Start

This paper reports a numerical simulation method for suppressing abnormal vibration on the cab caused by torsional vibration on the powertrain, using a mechanical dynamics analysis software. The simulation model for the numerical analysis is adopted to the powertrain. Seven design parameters were selected and optimized to minimize the acceleration of the vibration by using Design of Experiment (DOE). Validation tests were conducted on the optimized model, and a good agreement was achieved between the test results and the calculated ones. This new design has helped us a lot to save weight, cost and time by narrowing down design change proposals.
Technical Paper

Kinematical Models and Emulation of Multi-Axle Steering of Off-Highway Vehicles with Multi-Axle

The Kinematical models and Emulation of muti-axle steering of off-highway vehicles had been researched in this paper,that included the kinematical model of dozens of steering linkages, the relationship model of the steering linkages, the minimum steering radius and the wheel alignment, the mathematical model of the steering linkages and the steering system, and the model of the stability of the vehicle. The theory and method of the linkages optimization of multi-axle vehicles had been researched with kinematics theory. The simulation had been done on the multi-axle steering linkages of a eight-axle(8 X 8) off-highway vehiele, and the optimal parameters of the linkages had been obtained accordin to the simulation result and the optimal theory.