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The automotive industry’s journey towards fully autonomous vehicles brings more and more vehicle control systems. Additionally, the reliability and robustness of all these systems must be guaranteed for all road and weather conditions before release into the market. However, the ever-increasing number of such control systems, in combination with the number of road and weather conditions, makes it unfeasible to test all scenarios in real life. Thus, the performance and robustness of these systems needs to be proven virtually, via vehicle simulations. The key challenge for performing such a range of simulations is that the tire performance is significantly affected by the road/weather conditions. An end user must therefore have access to the corresponding tire models. The current solution is to test tires under all road surfaces and operating conditions and then derive a set of model parameters from measurements.

Electrification is getting more important in the aviation industry with the increasing need for reducing emissions of carbon dioxide and fuel consumption. It is crucial to assess the behavior of Li-Ion batteries at high-altitude conditions to design safe and reliable battery packs. This paper aims at benchmarking the performance of different formats of battery cells (pouch cells and cylindrical cells) in low-pressure environments. A test setup was designed and fabricated to replicate the standard procedure defined by the RTCA DO-311 standard, such as the altitude test and rapid decompression test. During the test voltage, current, temperature, and pressure were monitored, and the evaluation criteria is based on the capacity retention, along with the structural integrity of the cell. From preliminary tests, it was observed that cylindrical cells do not show a significant change in performance at low-pressure conditions thanks to their steel casing.

Harmony-with-traffic refers to the ability of autonomous vehicles to maximize the driving benefits such as comfort, efficiency, and energy consumption of themselves and the surrounding traffic during interactive driving under traffic rules. In the test of harmony-with-traffic, one or more background vehicles that can respond to the driving behavior of the vehicle under test are required. For this purpose, the functional requirements of car-following model for harmony-with-traffic evaluation are analyzed from the dimensions of test conditions, constraints, steady state and dynamic response. Based on them, an interactive car-following model (ICFM) is developed. In this model, the concept of equivalent distance is proposed to transfer lateral influence to longitudinal. The calculation methods of expected speed are designed according to the different car-following modes divided by interaction object, reaction distance and equivalent distance.

With the proliferation of ADAS and autonomous systems, the quality and quantity of the data to be used by vehicles has become crucial. In-vehicle sensors are evolving, but their usability is limited to their field of view and detection distance. V2X communication systems solve these issues by creating a cooperative perception domain amongst road users and the infrastructure by communicating accurate, real-time information. In this paper, we propose a novel Consolidated Object Data Service (CODS) for multi-Radio Access Technology (RAT) V2X communication. This service collects information using BSM packets from the vehicular network and perception information from infrastructure-based sensors. The service then fuses the collected data, offering the communication participants with a consolidated, deduplicated, and accurate object database. Since fusing the objects is resource intensive, this service can save in-vehicle computation costs.

The invention of the diesel common rail (DCR) fuel system has enabled a complete new performance scope for the operation of the Diesel Engine. Among the most important characteristics, the DCR fuel system provides increased fueling flexibility in both quantity and timing, improved packaging, relatively low weight, and attractive cost to the fuel system integrator. The four main top level requirements for DCR pumps have been identified: (1) Efficiency, (2) Function and Performance, (3) Size and Weight, and (4) Cost. In this paper, the development of key features of Stanadyne’s Modular DCR (MDCR) pump platform will first be described. Design strategies for fuel metering, robustness to debris, increased pressure, increased speed, and increase in B10 life for both an automotive MDCR pump and a heavy duty MDCR pump will be presented. Detailed results from an in-depth analysis of the pumps will be presented. Results of performance testing and durability testing will be presented.

Proton exchange membrane fuel cells are promising in the application of new energy vehicles and other fields. The performance test and analysis are critical components of the fuel cell research. A general procedure for data processing model and performance analysis method of fuel cell stacks were introduced based on a demonstration project of commercial fuel cell buses in Shanghai. To build the data processing model, the fixed node method was used to extract the effective operating data of fuel cell stack from the vehicle database. After data cleaning and conversion, taking fuel cell reversible recession into account, the processed data can be obtained. Data that had been processed and a semi-empirical model were used to accurately fit the polarization curve. Polarization curve is a pivotal approach to describe the performance of fuel cells.

Disposal of waste plastic materials is a challenge in today's scenario and disposal of waste vegetables and fruits are costing very high. This work is to use biobutanol from the waste vegetables and fruits along with pyrolyzed waste plastic oil to replace diesel. Various proportions of biobutanol (0-50%) and plastic oil (0-50%) are prepared and tested for solubility and properties. The obtained properties are compared with diesel engine fuel base properties to select a blend that possesses closer properties. The chosen blend is tested for performance in various intake air temperatures (50, 75 and 100°C); one of the temperatures among the three which is producing higher thermal efficiency is considered for further testing.

This program involved the detailed evaluation of a novel laser-based in-exhaust ammonia sensor using a diesel fuel-based burner platform integrated with an ammonia injection system. Test matrix included both steady-state modes and transient operation of the burner platform. Steady-state performance evaluation included tests that examined impact of exhaust gas temperature, gas velocity and ammonia levels on sensor response. Furthermore, cross sensitivity of the sensor was examined at different levels of NOX and water vapor. Transient tests included simulation of the FTP test cycles at different ammonia and NOX levels. A Fourier transform infrared (FTIR) spectrometer as well as NIST traceable ammonia gas bottles (introduced into the exhaust stream via a calibrated flow controller) served as references for ammonia measurement.

In recent years, intelligent connected vehicle has become an important direction for future automotive research and development. In-vehicle Time-Sensitive Network is the core communication technology of ICV, and network performance test is a necessary step in the development process. Therefore, this paper studies the Time-Sensitive Network performance test system. Firstly, a Time-Sensitive Network performance test framework is designed, and a test scheme is formulated. Then, a control method that can flexibly configure the network topology is proposed. Finally, the physical verification of the system is carried out, and the influence of factors such as network topology, message frame length and communication frequency on the network communication performance is analyzed, which proves the reliability of the system.

This SAE Standard establishes a uniform test procedure and performance requirements for personal watercraft floatation. This SAE Standard does not apply to outboard powered personal watercraft and jet powered surfboards.

Significant efforts have been made in internal combustion engine development to meet the most restrictive emission regulations. Analysis of in-cylinder pressure-time history is one of the most powerful tools to address combustion chamber design and engine calibration. This analysis provides information about load, knock occurrence and intensity, combustion phasing, combustion duration, shape of heat release rate curve and mass fraction burned. Aiming at an efficient real-time monitoring of combustion and engine performance, a processing framework was proposed. The proposed framework seeks to balance parameters accuracy with computational cost. For this, the number of points used on each parameter calculation is reduced by splitting the processing into two paths of data detailing and partitioning. Also, to reduce additional expenses with supplementary hardware, thermodynamics methods were applied to use only the in-cylinder pressure data.

This SAE Aerospace Recommend Practice (ARP) is intended to cover the external lights on fixed wing aircraft for illuminating the wing leading edge and engine nacelles and the upper surfaces of the wing. The addition of an ice detection system should be implemented when the areas to inspect are not visible from the aircraft cockpit. It is not intended that this recommended practice require the use of any particular light source such as halogen, LED, or other specific design of lamp.

Closed-cycle protective breathing apparatus, commonly referred to as rebreathers, or CCBA provide trained aircrew members or ground personnel with eye and respiratory protection from toxic atmospheres.

This SAE Standard covers un-shielded balanced single twisted pair data cable intended for use in surface vehicle cables for ≤100 Mb/s Ethernet applications. The tests in this document are intended to qualify cables for normal operation in an automotive environment while maintaining the necessary electrical properties for reliable data transmission.

Abstract The objective of the study was to evaluate the quasi-static and fatigue performance of automotive anti-roll bars (ARBs) under extreme environmental conditions. Flexural quasi-static and fatigue tests of SAE 1040 steel were conducted above and below the ductile-to-brittle transition temperature (DBTT) in flexure and compared with their room temperature performance. The flexural strength increased by decreasing the temperature to −40°C. The fatigue lives are determined for stress levels of 87%, 60%, and 30% of their flexural strength under displacement mode in constant amplitude loading. Experimental stress versus the number of cycles (S-N) curves of SAE 1040 steel state that all tube specimens have fatigue limits that were more than 100,000 cycles at −40°C. The fatigue life of the SAE 1040 tube exhibited infinite life below the ductile-to-brittle transition (DBT).

In the present work, Four-stroke DI diesel engine using Rape seed biodiesel was tested for performance and emissions characteristics. Compared to diesel, RSBD lowered the brake thermal efficiency by 5.7%, HC emissions by 28%, CO emissions by 23%, smoke emissions by 4%, and NOX emissions by 24%. To increase the thermal efficiency and to reduce the NOx emission using RSBD as fuel, the concept of thermal barrier coating on the piston was introduced along with 15% EGR. Due to the combined effort of oxygenated biodiesel and ceramic coating at the piston crown, the NOx emission increased significantly during the operation of the engine. Results show a 3.5% decrease in brake thermal efficiency, a 2.8% increase in HC emissions, a 4% increase in CO emissions, an additional 2% increase in smoke emissions, and a 6.2% increase in NOX emissions with a 15% EGR and TBC Piston over a standard diesel engine running on RSBD.

Visual sensors are widely used in autonomous vehicles (AVs) for object detection due to the advantages of abundant information and low-cost. But the performance of visual sensors is highly affected by low light conditions when AVs driving at nighttime and in the tunnel. The low light conditions decrease the image quality and the performance of object detection, and may cause safety of the intended functionality (SOTIF) problems. Therefore, to analyze the performance limitations of visual sensors in low light conditions, a controlled light experiment on a proving ground is designed. The influences of low light conditions on the two-stage algorithm and the single-stage algorithm are compared and analyzed quantificationally by constructing an evaluation index set from three aspects of missing detection, classification, and positioning accuracy.

The scenario-based test method is now drawing more and more attention in the field of the test for autonomous vehicles. The predefined scenarios are used in the safety verification and performance evaluation of autonomous vehicles. However, the traditional generation method for predefined scenarios is parameterized and open-looped, which makes it challenging to generate diverse and complex scenarios. It is critical when testing high-level autonomous vehicles to verify their reliability in multiple behavior transitions. In this paper, a generation method for the continuous scenario is proposed to realize a function-driven iteration of scenarios for autonomous driving systems (ADS). The method consists of a functional model of ADS and a formal description of abstract scenario.

This SAE Information Report establishes a minimum level of uniform recipes for contaminants which may be used when durability testing pneumatic components to obtain additional information on how a device may perform under more true-to-life operating conditions. This type of contamination testing, however, is not meant to replace the type of performance testing described in SAE J1409 and SAE J1410. Durability testing in the presence of contamination will yield results more reflective of actual in-service field conditions and provide an additional evaluation of pneumatic devices. While the contaminant supply rate and other test criteria of the device being tested must be set by the device manufacturer or user, the items covered in this document will be: