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In this paper, a gain-scheduling optimal control approach is proposed to enhance yaw stability of articulated commercial vehicles through active braking of the proper wheel(s). For this purpose, an optimal feedback control is used to design a family of yaw moment controllers considering a broad range of vehicle velocities. The yaw moment controller is designed such that the instantaneous tractor yaw rate and articulation angle responses are forced to track the target values at each specific vehicle velocity. A gain scheduling mechanism is subsequently constructed via interpolations among the controllers. Furthermore, yaw moments derived from the proposed controller are realized by braking torque distribution among the appropriate wheels. The effectiveness of the proposed yaw stability control scheme is evaluated through software-in-the-loop (SIL) co-simulations involving Matlab/Simulink and TruckSim under lane change maneuvers.

This paper investigates the yaw dynamic behaviour of a seven axle tractor semitrailer combination vehicle developed by VRDE (Vehicle Research & Development). The semitrailer has four steerable axles which follow command steering law i.e. all axles of semitrailer are steered in a particular relation with articulation of tractor. A 4 dof (degree of freedom) linear yaw plane model was developed for this combination vehicle. Yaw response characteristics such as lateral acceleration, yaw rate and articulation angle for step and sine steer is obtained from this model. Effects of speed on the above parameters are also studied to the same steering inputs. Lateral tyre forces due to semitrailer steering at various speeds are estimated to understand its distribution on each axle. Steady state yaw rate and articulation angle gain are obtained to predict the understeer / oversteer behaviour of combination vehicle.

Work solenoids are widely used in household appliances. The environment and design of this type application does not lead to solenoids for the earthmoving industry. This paper presents the environmental effects to be considered when designing a solenoid for the earthmoving industry. It further explains the need for, and type of, test necessary to validate the design. Finally a review of production quality procedures, necessary to insure reliable production parts is discussed.

This SAE Standard specifies requirements and design guidelines for electrical wiring systems of less than 50 V and cable diameters from 0.8 to 19 mm2 used on off-road, self-propelled earthmoving machines as defined in SAE J1116 and agricultural tractors as defined in ASAE S390.

This SAE Standard specifies requirements and design guidelines for electrical wiring systems of less than 50 V and cable diameters from 0.35 to 19 mm2 used on off-road, self-propelled earthmoving machines as defined in SAE J1116 and agricultural tractors as defined in ASAE S390.

This SAE Standard specifies requirements and design guidelines for electrical wiring systems of less than 50 V and cable diameters from 0.35 to 19 mm2 used on off-road, self-propelled earthmoving machines as defined in SAE J1116 and agricultural tractors as defined in ASAE S390.

This SAE Standard specifies requirements and design guidelines for electrical wiring systems of less than 50 V and cable diameters from 0.8 to 19 mm2 used on construction, agricultural, and general purpose industrial categories of off-road self-propelled work machines as defined in SAE J1116.

This SAE Standard specifies requirements and design guidelines for electrical wiring systems of less than 50 V and cable diameters from 0.8 to 19 mm2 used on construction, agricultural, and general purpose industrial categories of off-road self-propelled work machines as defined in SAE J1116.

Knitted wiremesh along with radial gas tight seals provide reliable mounting system for low temperature underbody converters. The compression characteristics of the wiremesh is modified by wire material, wire diameter, wire geometry, mesh crimp heights; wire density, wiremesh courses per inch, needle count, number of strands, wiremesh temper, wiremesh surface profile and surface characteristics. The radial mounting pressure provided by the wiremesh is matched with the mounting pressure requirement. Wiremesh systems can be tailored to any required radial mounting pressure from conventional to ultra thin-wall substrates. The wiremesh mounting system is proven durable, without any failure on more than 25 million underbody converters in light duty vehicles. Cp and Cpk show the capability of the manufacturing process. Thus the wiremesh mounting support is a viable alternate for low temperature gasoline and diesel applications.

A wind tunnel experiment has been conducted to determine the changes in drag and side force due to the presence and position of cab extenders on a model of a commercial tractor-trailer truck. The geometric variables investigated are the cab extenders angle of incidence, the tractor-trailer spacing and the yaw angle of the vehicle. Three cab extender angles were tested-0°, 15° (out) and -15° (in) with respect to the side of the tractor. The cab and trailer models have the same width and height. The minimum drag coefficient was found for the tractor and trailer combination when the cab extenders were set to 0° angle of incidence with respect to the headwind. This result holds for all yaw angles with moderate gap spacing between the tractor and trailer. This study suggests that commercial tractor-trailer trucks can benefit from adjustable cab extender settings; 0° when using a trailer and -15° when no trailer is used.

This SAE Recommended Practice establishes uniform engineering nomenclature for wide base disc wheels and demountable rims. This nomenclature and accompanying figures are intended to define fundamental wide base disc wheel and demountable rim terms. The dimensions given are those necessary to maintain serviceability and interchangeability of the wide base disc wheels and demountable rims with standard hardware. Valve clearances have not been included in this document.

This SAE Recommended Practice establishes uniform engineering nomenclature for wide base disc wheels and demountable rims. This nomenclature and accompanying figures are intended to define fundamental wide base disc wheels and demountable rim terms. The dimensions given are those necessary to maintain serviceability and interchangeability of the wide base disc wheels and demountable rims with standard hardware. Valve clearances have not been included in this document.

HIGH output per cubic inch of piston displacement is desirable not alone for the purpose of being able to transport more payload faster, but more particularly for the invariably associated byproduct of lower specific fuel consumption, and especially at road-load requirements. The only way of accomplishing this purpose is through the use of higher compression ratios, and the limiting factors for this objective are fuel distribution and the operating temperatures of the component parts. A manifold is proposed which not only definitely improves distribution at both full and road loads, but has the inherent additional advantage of reducing the formation of condensate, thus still further facilitating a reduction in road-load specific fuel consumption. Hydraulic valve lifters, obviation of mechanical and thermal distortion, and controlled water flow are the essentials in improved cooling.

In selecting springs for commercial vehicles, it is essential to consider the fundamental principles of the suspension system as a whole, as well as the specific spring characteristics. This paper discusses the applications of these principles; also, it compares the many types of springs available, including single leaf, multileaf, and two-stage leaf springs, and coil, rubber, and pneumatic springs. Among the considerations stressed are: the relationships of spring static deflections to vehicle pitch frequency and oscillation center location, the questionability of two-stage leaf springs, the disadvantages of single tapered leaf versus multi-leaf springs, the advantages of coil springs in low weight and variable rate, and why pneumatic springs are ideal for large load range, heavy commercial vehicles.

The wheel motor is a combination of hydro-motor and planetary transmission. Industrial, agricultural, construction and various types of public utility vehicles, which due to their design cannot use axle drives, make increasing use of the individual wheel drive. Speed, torque transmission, wheel bearings, valves for hydraulic operation and hydraulic engagement/disengagement are some of the requirements for wheel motor drives.

This recommended practice contains dimensions and tolerances for spindles in the interface area. Interfacing components include axle spindle, bearing cones, bearing spacer, seal and wheel hub. This recommended practice is intended for axles commonly used on Class 7 and 8 commercial vehicles. Included are SAE axle configurations FF, FL, R, N and P. SAE configurations FC, K, L, U, and W are not included, but may be added in the future.

In Automotive, Steel wheels are exponentially replaced by Aluminum wheels because of its feather light, agile performance and better acceleration. One such widely used size is 11.75 x 22.5 wheels for trucks and trailer segment. During the design stage of 11.75 x 22.5 wheel, the valve hole was placed away from the stress concentration zone to reduce the stress on the holes and also the design was validated through all conventional wheel rim testing methodologies (Like CFT, RFT and Bi-axial) and the wheel passed all the test requirements. During the field trials, failures were observed on the valve holes, despite of this hole was away from stress concentration region. Understood from the field trials that, the regular testing was not able to simulate the real field conditions for this particular size and changed the boundary condition in our FEA to simulate the actual conditions. After changing the boundary conditions, we could able to observe more stress in valve hole.

New technology placed on specific components within the wheel end system, required modifications to existing tapered wheel bearing adjustment procedures. A new method for vehicles, which use tapered roller bearings, required a procedure addressing new technologies for the wheel end system. OEM and service technicians would benefit from concise procedures. Technologies engineered and developed for ABS (Anti-skid Brake Systems), extended brake blocks and synthetic lubricants, required research for the data base. Research to optimize the operating environment through improved maintenance procedures helped in achieving optimum wheel system operation. A tapered wheel bearing adjustment procedure and visual chart are the results profiting the vehicle manufacturers and field service technicians.

This paper describes how the needs of the truck end-user have changed under the pressures of deregulation and competition, and how the truck supply community has responded. It observes that traditional management and hardware responses are yielding diminishing improvements. Significant further improvement is postulated based on application of electronic technology to functional control of a “truck system”. This is defined as a technological discontinuity where a new perspective, “thinking systems” will be needed. The post-1995 truck system is described; and what “thinking systems” entails and “how to create a system” are discussed. It is further postulated that this change in technology will have major impacts on the structure of the truck manufacturing industry, and the capabilities required of its management and technical communities.

Formulas are derived to show that moving elements of a drive train can contribute to the energy seen by the clutch plates. Oscillograph traces, sample calculations and photographs of failed plates show actual energy at failure of test plates. The formula is presented for calculating instantaneous energy when coefficient of friction, apply pressure and slip speed are known or can be estimated.