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Abstract When commercial vehicles drive in a mountainous area, the complex road condition and long slopes cause frequent acceleration and braking, which will use 25% more fuel. And the brake temperature rises rapidly due to continuous braking on the long-distance downslopes, which will make the brake drum fail with the brake temperature exceeding 308°C [1]. Meanwhile, the kinetic energy is wasted during the driving progress on the slopes when the vehicle rolls up and down. Our laboratory built a model that could calculate the distance from the top of the slope, where the driver could release the accelerator pedal. Thus, on the slope, the vehicle uses less fuel when it rolls up and less brakes when down. What we do in this article is use this model in a real vehicle and measure how well it works.

The emergence of tougher environmental legislations and ever increasing demand for increased ride comfort, fuel efficiency, and low emissions have triggered exploration and advances towards more efficient vehicle gearbox technologies. The growing complexity and spatial distribution of such a mechatronic gearbox demands precise timing and coordination of the embedded electronics, integrated sensors and actuators as well as excellent overall reliability. The increased gearbox distributed systems have seen an increased dependence on sensors for feedback control, predominantly relying on hardware redundancy for faults diagnosis. However, the conventional hardware redundancy has disadvantages due to increased costs, weight, volume, power requirements and failure rates. This paper presents a virtual position sensor-based Fault Detection, Isolation and Accommodation (FDIA), which generates an analytical redundancy for comparison against the actual sensor output.

This manuscript provides a review of different types and categorization of the chassis dynamometer systems. The review classifies the chassis dynamometers based on the configuration, type of rollers and the application type. Additionally the manuscript discusses several application examples of the chassis dynamometer including: performance and endurance mileage accumulation tests, fuel efficiency and exhaust emissions, noise, vibration and harshness testing (NVH). Different types of the vehicle attachment system in the dynamometer cell and its influences on the driving force characteristics and the vehicle acoustic signature is also discussed. The text also highlights the impact of the use of the chassis dynamometer as a development platform and its impact on the development process. Examples of using chassis dynamometer as a development platform using Vehicle Hardware In-the-Loop (VHiL) approach including drivability assessment and transmission calibrations are presented.

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.

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.

The emission legislations are becoming increasingly strict all over the world and India too has taken a big leap in this direction by signaling the migration from Bharat Stage 4 (BS 4) to BS 6 in the year 2020. This decision by the Indian government has provided the Indian automotive industry a new challenge to find the most optimal solution for this migration, with the existing BS 4 engines available in their portfolio. Indian market for the LCV segment is highly competitive and cost sensitive where the overall vehicle operation cost (vehicle cost + fluid consumption cost) is the most critical factor. The engine and after-treatment technology for BS 6 emission levels should consider the factors of minimizing the additional hardware cost as well as improving the fuel efficiency. Often both of which are inversely proportional. The presented study involves the optimization of after treatment component size, layout and various systems for NOx and PM reduction.

ERTS is a computer controlled golf car whose primary functional goal is autonomous real-world navigation. Its mission is to serve as a platform for collaborative research in diverse areas of cognitive robotics, human-computer interaction, among others, as well as basic research in embedded and real-time systems. This purpose demands a highly flexible platform on which it is relatively easy to configure and access resources ranging from vehicle components to sensor hardware. One avenue we are exploring toward this end is a uniform file-space interface, based in the Plan 9 operating system that originated at Bell Labs, and more recently, the work of Brown and Pisupati. They extended the approach for embedded and system-on-chip applications. We advocate synchronous design methods, where applicable, as this presents a more tractable model for students and researchers with higher experimental aims.

Rapid control prototyping (RCP) is a widely used technique for verifying a controller's functional behavior. Typically, RCP uses a target processor with ample processing power and memory, which makes the technique attractive for engineers exploring new concepts. However, a large gap often exists between the RCP target and the production ECU in terms of the available code generation technology, the supporting tool chain, and I/O hardware. Consequently, significant work is required when migrating a controller from RCP to production. Furthermore, due to cost constraints, RCP systems are difficult to deploy in large numbers for fleet testing or preproduction trials. In response to the challenges associated with RCP, automotive engineers are moving towards a technique called on-target rapid prototyping (OTRP).

The tractor trailer models discussed in this paper were for a real-time hardware-in-the-loop (HIL) simulation to test heavy truck electronic stability control (ESC) systems [1]. The accuracy of the simulation results relies on the fidelity and accuracy of the vehicle parameters used. However in this case where hardware components are part of the simulation, their accuracy also affects the proper working of the simulation and ESC unit. Hence both the software and hardware components have to be validated. The validation process discussed in this paper is divided into two sections. The first section deals with the validation of the TruckSim vehicle model, where experimental data is compared with simulation results from TruckSim. Once the vehicle models are validated, they are incorporated in the HIL simulation and the second section discusses the validation of the whole HIL system with ESC.

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.