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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.

This paper presents an analysis of coupled longitudinal and lateral dynamics of a 4×4 hybrid-electric off-road vehicle (HEV) with two passive driveline systems, including drivelines with (i) an interaxle open symmetrical differential in the transfer case and (ii) a locked transfer case, i.e., positive engagement of two axles. The axle differentials are open. As the study proved, lateral dynamics of the 4×4 HEV, characterized by the tire side forces, vehicle lateral acceleration, yaw rate and tire gripping factors can be impacted by the tire longitudinal forces, whose magnitudes and directions (positive-negative) strongly depend on the driveline characteristics. At the same time, the tire side forces impact the relation between the longitudinal forces and tire slippages.

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.

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.

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

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

Applies to hydraulic fluid power valves as applied to Off-Road Self-Propelled Work Machines defined in SAE J1116.

This SAE Recommended Practice establishes a test procedure for measuring pneumatic system differentials and time relationships for 125 psig (862 kPa) nominal air pressure brake systems.

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.

This SAE Recommended Practice sets forth the instrumentation and procedures to be used in measuring exterior sound levels of self-propelled agricultural field equipment of 15 kW (20 net engine hp) or greater. It is not intended to cover operation of safety devices (such as alarms), or equipment used primarily in stationary operation. The sound levels obtained by using this test procedure are repeatable and representative of the higher range of sound levels generated by the machine in normal road transport. The sound levels are not intended to represent the average or equivalent sound levels over a field use cycle.

This SAE Recommended Practice sets forth the instrumentation and procedures to be used in measuring exterior sound levels of self-propelled agricultural field equipment of 15 kW (20 net engine hp) or greater. It is not intended to cover operation of safety devices (such as alarms), or equipment used primarily in stationary operation. The sound levels obtained by using this test procedure are repeatable and representative of the higher range of sound levels generated by the machine in normal road transport. The sound levels are not intended to represent the average or equivalent sound levels over a field use cycle.