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A novel speed and position dependent Lane Keeping Assistance (LKA) control strategy for heavy vehicles is proposed. This LKA system can be implemented with any torque overlay system capable of accepting external position or torque commands. The proposed algorithm tackles the problem of lane keeping in two ways from a heavy vehicle's perspective. First, it stabilizes the vehicle's lateral position by bringing it to the center of the lane and giving it the correct heading to stay there. This is done using a speed and position dependent control strategy that becomes less aggressive as the vehicle's speed increases and as it gets closer to the center of the lane. Such speed and position dependency is especially critical in heavy vehicles where unnecessary aggressive control can lead to oscillations about the lane's centerline when cruising at high speeds.

In today’s automobile industry refined NVH performance is a key feature and of high importance governing occupant comfort and overall quality impression of vehicle. In this paper interior noise and vibration measurement is done on one of the light truck and few dominant low frequency noise booms were observed in operation range. Modal analysis was done for the cabin at virtual as well as experimental level and few modes were found close to these noise booms. Vibrations were measured across the cabin mounts and it was found that the isolation of front mounts is not effective at lower frequencies. Taking this as an input, the mount design was modified to shift the natural frequency and hence improve the isolation behavior at the lowest dominant frequency. This was followed by static and dynamic measurement of the mounts at test rig level to characterize the dynamic performance and stiffness conclusion.

Nowadays, investigating underhood airflow by using numerical simulation is a standard task in the development process of passenger cars and commercial vehicles. Numerous publications exist which deal with simulating the airflow through the engine compartment of road vehicles. However, hardly anything can be found which deals with off-road vehicles and nothing exists which focuses on snowmobiles. In the presented paper the airflow and the thermal conditions inside the engine compartment of a snowmobile are investigated by the usage of computational fluid dynamics (CFD) as well as experimental methods. Field tests at arctic conditions have been conducted on a serial snowmobile to measure temperatures inside the compartment and to gain realistic boundary conditions for the numerical simulation. Thermocouples (type K) were attached under the hood to measure exhaust, air, coolant and surface temperatures of several components at previously defined load cases.

This paper presents a study related to an Articulated Amphibious All-Terrain Tracked Vehicle (ATV) characterized by a modular architecture. The ATV is composed by two modules: the first one hosts mainly the vehicle engine and powertrain components, meanwhile the second one can be used for goods transportation, personnel carrier, crane and so on. The engine torque is transmitted to the front axle sprocket wheel of each module and finally distributed on the ground through a track mechanism. The two modules are connected through a multiaxial joint designed to guarantee four relative degrees of freedom. To steer the ATV, an Electro Hydraulic Power System (EHPS) is adopted, thus letting the vehicle steerable on any kind of terrain without a differential tracks speed. The paper aims to analyze the steady-state lateral behavior of the ATV on a flat road, through a non-linear mathematical vehicle model built in Matlab/Simulink environment.

Autonomous vehicle operation is dependent upon accurate position estimation and thus a major concern of implementing the autonomous navigation is obtaining robust and accurate data from sensors. This is especially true, in case of Inertial Measurement Unit (IMU) sensor data. The IMU consists of a 3-axis gyro, 3-axis accelerometer, and 3-axis magnetometer. The IMU provides vehicle orientation in 3D space in terms of yaw, roll and pitch. Out of which, yaw is a major parameter to control the ground vehicle’s lateral position during navigation. The accelerometer is responsible for attitude (roll-pitch) estimates and magnetometer is responsible for yaw estimates. However, the magnetometer is prone to environmental magnetic disturbances which induce errors in the measurement.

This SAE Recommended Practice establishes uniform test procedures and performance requirements for engine-off heating, ventilation, and air conditioning (HVAC) systems in order to achieve driver thermal comfort in both winter and summer rest periods. This specification will apply to heavy trucks with and without sleeper compartments, including but is not limited to Class 6, 7, and 8 powered vehicles.

This SAE Recommended Practice establishes uniform test procedures and performance requirements for engine-off heating, ventilation, and air conditioning (HVAC) systems in order to achieve driver thermal comfort in both winter and summer rest periods. This specification will apply to heavy trucks with and without sleeper compartments, including but is not limited to Class 6, 7, and 8 powered vehicles.

This SAE Recommended Practice establishes a uniform test procedure for determining performance levels of operator enclosure panel type air filters on off-road, self-propelled work machines used in construction, general-purpose industrial, agriculture, and forestry as defined in SAE J1116 and equipped with an operator enclosure with a powered fresh air system.

This SAE Standard describes methods for evaluating the performance of the systems detection device, the minimum detection areas behind the machine, the visual and audible information presented to the operator and ground personnel, and the systems fault detection requirements. Also included are operator system function tests and maintenance procedures.

This SAE Information Report provides basic information about the issues surrounding the administration of stationary, infield sound testing of snowmobiles. The information provided herein is meant to enhance safety, improve the environment and promote uniform testing.

This SAE Information Report provides basic information about the issues surrounding the administration of stationary, infield sound testing of snowmobiles. The information provided herein is meant to enhance safety, improve the environment and promote uniform testing.

This SAE Information Report provides basic information about the issues surrounding the administration of stationary, infield sound testing of snowmobiles. The information provided herein is meant to enhance safety, improve the environment, and promote uniform testing.

Abstract In this article, a new road load simulation technology is presented for commercial vehicle driveline. In order to assess the performance of vehicle driveline, the chassis dynamometer system is introduced on the basis of the traditional vehicle driveline test bench, which improves the accuracy of the simulation system without the need of complex modeling of commercial vehicle tire dynamics. The vertical load of the vehicle is emulated by the hydraulic loading mechanism, and the influence of the vertical load on commercial vehicle driveline is emulated when the vehicle passes the bumpy road. The evaluate control method of commercial vehicle acceleration inertia based on wheel rotational speed and vehicle dynamics model is designed.

Networking is a need for interlinking todays and future electronic modules into systems. Networked systems offer reduced wiring harness, more open system expandability and an additional degree of freedom for system optimization. On the other hand networked systems represent highly complex problems for the system designers and therefore require correspondingly powerful tools. Subsequently the characteristics of networking are described based on the example of the CAN-network-protocol. A set of requirements for needed tool support is derived from the inherent networked system characteristics. A set of CAN network development tools is described - Simulator, Emulator, Analyzer, handy NetTest, PcNet-interface - supporting the various needs in the different design phases. Finally some future activities are described depicting tools enhancement and integration. In addition research activities are mentioned focusing on definition and evaluation of higher protocol layers.

Since defining quality so it will be accepted from company to company is a difficult task. This paper will discuss definitions of quality and how metrology can assist a company in defining its' quality. The title; Metrology:A Definition of Quality implies an explanation of how metrologists thinking has become important to companies committed to quality. This paper discusses the advantages quality programs derive from having metrology heavily involved in their processes and procedures. This paper also talks about the changing role of metrologists from strictly calibrating of the test equipment to applying process metrology in order to ensure the overall quality of the products.

This SAE Recommended Practice provides guidance for the construction, operation, and maintenance of CNG powered medium and heavy-duty trucks. The intent of this document is to cover TRUCKS (6350 kg (14 001 gvw pounds) and above) and specifically excludes passenger vehicles such as: buses, recreational vehicles, motor homes and/or passenger vehicles which may incorporate a truck chassis in their construction.

This SAE Recommended Practice provides guidance for the construction, operation, and maintenance of CNG powered medium and heavy-duty trucks. The intent of this document is to cover TRUCKS (6350 kg (14 001 gvw pounds) and above) and specifically excludes passenger vehicles such as: buses, recreational vehicles, motor homes and/or passenger vehicles which may incorporate a truck chassis in their construction.

Abstract HVAC systems of passenger cars and especially their air purification performance got more and more in focus during the last years. One reason is the overall increased attention to air quality and its effect on human health. Recently, the WHO further tightened the recommended values for many pollutants. This will likely intensify the trend to more complex systems for improving the air purification functionalities. But, up to now there is no standard method for air purification performance testing. Existing standards cover the vehicle cabin air quality only regarding material emissions. Several studies address assessing the performance of air purification functionalities in most cases by real driving tests typically performed in urban areas. This approach results in proper values for the basic efficiency of single systems.

This procedure incorporates test cycles that produce relative fuel economy data relating to long haul, short haul, and local driving patterns, or any combination of these and to those components developed to improve fuel economy for these patterns. The tests conducted on a specific vehicle are to reflect that vehicle's general mode of operation. The procedure is intended to be used under controlled, warmed-up conditions on a test tract or on suitable roads. A minimum of two vehicles running simultaneously is required. Test condition recommendations are provided for undertaking this engineering test. If it is necessary to conduct a test outside of these test conditions, the purpose of the test and the variant conditions should be recorded and noted whenever the results are reported.

This procedure applies to hydraulic fluid power valves as applied to self-propelled work machines as referenced in SAE J1116.