On-road Testing Research Articles

Impact of Road Marking Retroreflectivity on Machine Vision in Dry Conditions: On-Road Test.

(1) Background: Due to its high safety potential, one of the most common ADAS technologies is the lane support system (LSS). The main purpose of LSS is to prevent road accidents caused by road departure or entrance in the lane of other vehicles. Such accidents are especially common on rural roads during nighttime. In order for LSS to function properly, road markings should be properly maintained and have an adequate level of visibility. During nighttime, the visibility of road markings is determined by their retroreflectivity. The aim of this study is to investigate how road markings’ retroreflectivity influences the detection quality and the view range of LSS. (2) Methods: An on-road investigation comprising measurements using Mobileye and a dynamic retroreflectometer was conducted on four rural roads in Croatia. (3) Results: The results show that, with the increase of markings’ retroreflection, the detection quality and the range of view of Mobileye increase. Additionally, it was determined that in “ideal” conditions, the minimal value of retroreflection for a minimum level 2 detection should be above 55 mcd/lx/m2 and 88 mcd/lx/m2 for the best detection quality (level 3). The results of this study are valuable to researchers, road authorities and policymakers.

Performance Improvement of a Switched Reluctance Motor and Drive System Designed for an Electric Motorcycle

In this paper, the implementation of a switched reluctance motor (SRM) and drive system for the propulsion system of a two-seat electric motorcycle is described. The overall design focuses on the required vehicle speed, acceleration, driving distance, and overall system cost, as well as reliability. The performance of the three-phase 6/4 pole (six-stator pole and four-rotor pole) and four-phase 8/6 pole (eight-stator pole and six-rotor pole) are investigated and compared by static performance analysis and dynamic performance analysis. Their performance is further investigated by finite element analysis. The indirect torque controller in a drive system for optimal torque and efficiency operation is also mentioned. A methodology for rotor position detection and its hardware implementation are also proposed. The designed 3.5 kW three-phase 6/4 pole SRM and its drive system were constructed and tested on the test bench. A maximum efficiency of about 82% could be achieved for the SRM and drive system. It was also installed on a 120-cc electric motorcycle, and the vehicle’s performance was also validated by on-road and dynamometer testing. The maximum vehicle speed reached was 82 km/h, and a cruising distance of about 98 km at a constant speed of 40 km/h was measured.

Variability of fuel consumption and CO2 emissions of a gasoline passenger car under multiple in-laboratory and on-road testing conditions

An increasing divergence regarding fuel consumption (and/or CO2 emissions) between real-world and type-approval values for light-duty gasoline vehicles (LDGVs) has posed severe challenges to mitigating greenhouse gases (GHGs) and achieving carbon emissions peak and neutrality. To address this divergence issue, laboratory test cycles with more real-featured and transient traffic patterns have been developed recently, for example, the China Light-duty Vehicle Test Cycle for Passenger cars (CLTC-P). We collected fuel consumption and CO2 emissions data of a LDGV under various conditions based on laboratory chassis dynamometer and on-road tests. Laboratory results showed that both standard test cycles and setting methods of road load affected fuel consumption slightly, with variations of less than 4%. Compared to the type-approval value, laboratory and on-road fuel consumption of the tested LDGV over the CLTC-P increased by 9% and 34% under the reference condition (i.e., air conditioning off, automatic stop and start (STT) on and two passengers). On-road measurement results indicated that fuel consumption under the low-speed phase of the CLTC-P increased by 12% due to the STT off, although only a 4% increase on average over the entire cycle. More fuel consumption increases (52%) were attributed to air conditioning usage and full passenger capacity. Strong correlations (R2 > 0.9) between relative fuel consumption and average speed were also identified. Under traffic congestion (average speed below 25 km/hr), fuel consumption was highly sensitive to changes in vehicle speed. Thus, we suggest that real-world driving conditions cannot be ignored when evaluating the fuel economy and GHGs reduction of LDGVs.

Electric Vehicle Energy Consumption Estimation with Consideration of Longitudinal Slip Ratio and Machine-Learning-Based Powertrain Efficiency

Electric vehicles (EVs) are considered one of the most promising ways to reduce greenhouse gas (GHG) emissions and address fossil fuel shortage. However, due to EV's limited driving range and battery's fluctuating capacity at different temperatures, EV drivers may question EVs’ ability to reach their destinations. In light of this, an accurate EV energy consumption estimation/prediction is vital to relieve drivers' concerns. This paper proposes an EV energy consumption estimation framework that explicitly considers the vehicle longitudinal wheel slip ratio. Besides, a machine-learning-based dynamic efficiency map is devised to capture the energy transfer ratio between electric motor and battery. Furthermore, a mixed second-order L1/H2 estimator is used to calculate the derivatives of velocity data. The method is evaluated based on on-road EV test data, and the result testifies its enhanced performance over a baseline method.

Trip Based Modeling of Fuel Consumption in Modern Heavy-Duty Vehicles Using Artificial Intelligence

Heavy-duty trucks contribute approximately 20% of fuel consumption in the United States of America (USA). The fuel economy of heavy-duty vehicles (HDV) is affected by several real-world parameters like road parameters, driver behavior, weather conditions, and vehicle parameters, etc. Although modern vehicles comply with emissions regulations, potential malfunction of the engine, regular wear and tear, or other factors could affect vehicle performance. Predicting fuel consumption per trip based on dynamic on-road data can help the automotive industry to reduce the cost and time for on-road testing. Data modeling can easily help to diagnose the reason behind fuel consumption with a knowledge of input parameters. In this paper, an artificial neural network (ANN) was implemented to model fuel consumption in modern heavy-duty trucks for predicting the total and instantaneous fuel consumption of a trip based on very few key parameters, such as engine load (%), engine speed (rpm), and vehicle speed (km/h). Instantaneous fuel consumption data can help to predict patterns in fuel consumption for optimized fleet operations. In this work, the data used for modeling was collected at a frequency of 1Hz during on-road testing of modern heavy-duty vehicles (HDV) at the West Virginia University Center for Alternative Fuels Engines and Emissions (WVU CAFEE) using the portable emissions monitoring system (PEMS). The performance of the artificial neural network was evaluated using mean absolute error (MAE) and root mean square error (RMSE). The model was further evaluated with data collected from a vehicle on-road trip. The study shows that artificial neural networks performed slightly better than other machine learning techniques such as linear regression (LR), and random forest (RF), with high R-squared (R2) and lower root mean square error.

Impact of post-stroke cognitive dysfunction on driving ability

The paper aims to present the current views on the impact of post-stroke cognitive deficits on driving ability, and diagnostic assessment practices in this area. Firstly, the neuropsychological consequences of stroke are briefly presented. This part focuses specifically on visuospatial and executive dysfunctions. Among those dysfunctions, unilateral neglect, especially as it is frequently associated with anosognosia, may have the greatest impact on driving ability, leading to an increased accident risk. Then, different approaches to assessing fitness to drive after stroke are presented, including on-road testing, testing with the use of simulator, and clinical assessment focusing on cognition. The role of cognitive assessment in predicting fitness to drive is described in more detail. The Clock Drawing Test is the most appropriate screening measure in this context, as it engages both visuospatial and executive functions. The Trail Making Test is the most popular working memory test in the context of drivers’ assessment, as it requires visual search and psychomotor speed. The Rey Complex Figure Test is another commonly used test. It requires visuospatial and executive functions, and may also serve as a measure of visuospatial memory. Finally, the legal aspects of the assessments are discussed with reference to the practices used in Great Britain, Belgium, Sweden, and Germany. In Poland, there are no detailed standards for post-stroke fitness-to-drive assessment.

Association between on-road driving performance test and usual walking speed or sustainable attention in the elderly; Preliminary survey

Objective An increase in older drivers has been widely recognized in Japan; accordingly, screening to prevent traffic accidents is a crucial issue for safe driving. As a preliminary study, we examined the association between on-road driving performance and cognition or physical performance in older individuals. Methods The survey was conducted in 2020, and the participants were recruited in Katagami City, Akita, Japan. The Road Test was used to assess on-road driving performance. The physical assessment comprised the usual walking speed (UWS) and grip strength (GS), and the cognitive evaluation consisted of the National Center for Geriatrics and Gerontology Functional Assessment Tool (NCGG-FAT) and the Japanese version of Stroke Drivers’ Screening Assessment (J-SDSA). A multiple regression model was also applied to examine the association between on-road driving performance and the physical items or cognitive domains of the NCGG-FAT and the J-SDSA in older individuals. Results Twenty-one participants (mean age ± standard deviation [SD], 77.0 ± 5.5 years) were included in this study. A correlation analysis showed that the on-road test score was correlated with performances on the UWS (r = 0.53, p = .002), the word list memory (WM) test (r = 0.44, p = .046), the trail-making test-A (TMT-A) (r = −0.44, p = .048), the SDSA dot cancelation (DC) test (r = −0.63, p = .002), and the SDSA squares matrix compass test (SM) (r = 0.54, p = .048). According to a stepwise linear regression, the on-road test score was associated with the UWS (β = −0.01, p = .003) and the SDSA DC (β = 4.89, p = .01), with an adjusted R 2 = 0.54. Conclusions The results of the study suggested that the UWS and sustainable attention might be potential factors influencing on-road driving performance. Our preliminary findings warrant further investigation.

Effect of Memantine on Prolonging Safe Driving in Early AD: a Pilot Study.

BackgroundTo determine the feasibility of conducting an RCT on the potential effectiveness of memantine hydrochloride in prolonging safe driving in mild AD.MethodsA placebo-controlled, double blind randomized trial was conducted. Forty-three individuals ≥60 with mild AD met screening criteria and were randomized. Driving ability was measured by a standardized on-road driving test. Outcomes were driving capacity at 6 and 12 months and completion of the 12-month intervention.ResultsOf 43 participants randomized, 59% of the memantine group and 52% of the placebo group completed the on-road test at 12 months (p = .66). All 13 memantine group participants maintained their driving status at 12 months, whereas only 8 of the 11 placebo group participants did (p = .040, OR = 4.45).ConclusionsResults provide the framework for designing a rigorous multisite clinical trial of memantine effect on maintaining driving capacity in mild AD.

24 Reducing vibrations to improve infant patient safety during transportation

Abstract Primary Subject area Neonatal-Perinatal Medicine Background Each year, thousands of newborns are transported by air or ground ambulance to receive specialized medical care. For neurologically immature and physiologically compromised infants, especially preterm infants, the noise and vibration exposure during transport are high despite preventative measures, and may be an important contributor to brain injury risk. Objectives To develop a new tool to investigate vibrations during neonatal transport and mitigation strategies. Design/Methods Proof of concept study including 3 steps: 1) Characterization of the vibrations during transport. Accelerometer sensors placed on different layers of the Neonatal Patient Transport System (NPTS) (neonate manikin, mattress, incubator, deck, stretcher, and vehicle floor) with a variety of ambulance on road tests performed to capture data. 2) Experimentation - A shaker table was used to develop a standardized test environment. Vibration testing was performed, with the entire NPTS mounted on the shaker table. 3) Mitigation - Shaker table tests were repeated using different configurations of mattress and harness types on manikins with different bodyweights. Results 1) Characterization: Road transport exposed the manikin’s head to vibrations that exceeded adult standards. Examining the frequency spectra of the accelerometer signals across different layers of the NPTS suggests that two interfaces, stretcher/vehicle floor and incubator/deck, may be critical for intervention to mitigate the vibrations, as they both showed the highest gains in vibration power. 2) Experimentation: Comparison between the on-road and shaker table tests showed that the shaker table was able to reproduce on-road transportation with acceptable fidelity. The shaker table setup can serve as a standardized environment to explore the impact of several NPTS design variables on vibrations transmitted to the patient. 3) Mitigations: Different mattresses were shown to influence the vibrations experienced by the manikin. The head restraint harness type showed an amplitude reduction of the peak frequency component for all experiment types and for most mattress types compared to a standard 5-point harness. Conclusion Our study demonstrated that: i) vibrations during neonatal transport can exceed adult standards; ii) acceptable fidelity simulation of road conditions can be achieved using a shaker table system; and iii) the most effective approach for vibration mitigation should consider the whole NTPS, instead of focusing solely on the isolette.

NH3 and N2O Real World Emissions Measurement from a CNG Heavy Duty Vehicle Using On-Board Measurement Systems

The development and utilization of a series of after-treatment devices in modern vehicles has led to an increase in emissions of NH3 and/or N2O with respect to the past. N2O is a long-lived greenhouse gas and an ozone-depleting substance, while NH3 is a precursor of secondary aerosols in the atmosphere. Certain regions, e.g., the EU and the USA, have introduced limits to the emissions of NH3 or N2O for vehicles tested in the laboratory. However, due to the lack of on-board systems that allow for the measurement of these compounds when the regulations were developed, these vehicles’ real-world emissions have not been regulated. This work evaluates on-board systems that could allow measuring real-world emissions of NH3 and N2O from heavy-duty vehicles. In particular, emissions of NH3 or N2O from a Euro VI Step D urban/interurban bus fueled with Compressed Natural Gas were measured using the HORIBA’s OBS-ONE-XL, which is based on a specifically developed technique called Infrared Laser Absorption Modulation, and uses a Quantum Cascade Laser as a light source. They were also measured using the PEMS-LAB, which is a more conventional FTIR-based system. Emissions were measured under real-world driving conditions on the road and in a climatic test cell at different ambient temperatures. For most of the conditions tested, the on-board systems correlated well with a laboratory-grade FTIR used as reference. In addition, a good correlation with R2 > 0.9 was found for the N2O concentrations measured by OBS-ONE-XL and PEMS-LAB during on-road testing.

Understanding elevated real-world NOx emissions: Heavy-duty diesel engine certification testing versus in-use vehicle testing

For the first time, nitrogen oxide (NOx) emissions were systematically investigated during different operating conditions from a single test article on a chassis dynamometer, under real-world (on-road) conditions, on an engine dynamometer after the engine was pulled out of the vehicle, and again on a chassis dynamometer when the engine was installed back in the vehicle. The main goal of this study was to understand the discrepancies between certification and in-use NOx emission rates from a heavy-duty diesel vehicle (HDDV) with an engine with diesel particulate filter (DPF) and selective catalytic reduction (SCR) aftertreatment. The results showed that in-use NOx emissions over urban driving cycles were above the 0.2 g/bhp-hr NOx standard for most test conditions, ranging from 0.16 to 0.7 g/bhp-hr, with the highest NOx emissions for the chassis dynamometer testing. For the freeway/steady-state testing, the results were generally lower compared with the results of urban driving cycles, with values of 0.3 g/bhp-hr or less. For the Urban Dynamometer Driving Schedule (UDDS) cycle, NOx emissions were lowest for the engine dynamometer testing, followed by the on-road testing, and the chassis dynamometer testing. The differences between the tailpipe NOx emissions for the different types of tests could be attributed to differences in SCR inlet temperatures and engine-out NOx emissions.

Application of TRIZ Method in Developing Vehicle Lane Support System Testing Infrastructure for Raining Condition


 
 
 Theory of Inventive Problem Solving (TRIZ) is an inventive problem-solving method developed to find a solution for issues involving contradictions. The TRIZ method was applied to develop a new method of simulating raining weather conditions for vehicle lane support system (LSS) on-road testing infrastructure. The objective of the project was to develop a mechanical solution capable of dispensing a consistent amount of water to a moving vehicle to simulate raining weather conditions, while at the same time it is portable and easy to set up. Based on the requirement, the TRIZ 40 inventive principles were applied as the solution, based on the principles of “the other way around”, “segmentation”, “dynamicity” and “feedback”. The specific solution generated based on the inventive principles identified was to make both the vehicle and the rain simulating machine movable during the on-road test. This is achieved by creating a customized rain machine that can be fitted onto a moving vehicle. This simple setup enabled both vehicle-under-test (VUT) and the rain machine vehicle to move simultaneously during the test, at any test speed and type of test track desired. Furthermore, the rain machine itself is designed with the capability to dispense the water by using a control unit, hence making the testing method safer and less human effort required. Based on the literature review, there is yet no similar solution for simulating raining conditions in LSS on-road test made using the same principle developed in this project. The innovative portable rain machine developed in this project could also be applied for other Advanced Driver Assistance System (ADAS) test protocols requiring similar raining testing conditions especially involving moving VUT.
 
 

Towards Building eco-friendly and emission less Electric Scooter

Electric vehicles are becoming more important, as not only to reduce carbon emission but also to reduce the dependency on normal combustion engine vehicles. Most of the universities have really big campuses. To make the mobility in campus easier, the harmless and power-controlled vehicle with safety technologies is introduced. Besides, it also reduces time consumption. Further, it aids differently abled persons and aged professors. This paper presents the design and development of a compact, portable and weightless electric skating scooter. The vehicle body design is inspired from the sea cartilaginous fish ‘String Ray’. It also includes mechanical features like front shock absorber, handlebar break control, portable and handle bar height adjustment. The electrical and electronic features such as obstacle detector, fingerprint and RFID (Radio-frequency identification) access, battery management system (BMS) etc., help towards building a smart vehicle. Besides, it also provides a vehicle management system for tracking the user details, location and condition of the vehicle through a server. The proposed system with addition of mechanical, electrical and electronic features will help towards enhancing the performance of an electric scooter for easy mobility. The results obtained from the on-road test, CADD software and the implementation of vehicle management system has been discussed.

A Comparison of Lane Marking Detection Quality and View Range between Daytime and Night-Time Conditions by Machine Vision

Lateral support systems in vehicles have a high potential for reduction of lane departure crashes. To profit from their full potential, such systems should function properly in adverse conditions. Literature indicates that their accuracy varies between day and night-time. However, detailed quantifications of the systems’ performance in these conditions are rare. The aim of this study is to investigate the differences in detection quality and view range of Mobileye 630 in dry daytime and night-time conditions. On-road tests on four rural road sections in Croatia were conducted. Wilcoxon signed-rank test was used to test the difference between the number of quality rankings while absolute average, average difference and standard deviation were used to analyse the view range. Also, a paired samples t-test was used to test the difference between conditions for each line on each road. The overall results confirm that a significant difference in lane detection quality view range exists between tested conditions. “Medium” and “high” detection confidence (quality level 3 and 2), increased by 5% and 8% during night-time compared to daytime while level 0 (“nothing detected”) decreased by 12%. The view range increased (almost 16% for middle line) during daytime compared to night-time. The findings of this study expand the existing knowledge and are valuable for research and development of machine-vision systems but also for road authorities to optimize the markings’ quality performance.

Design and development of MR damper for two wheeler application and Kwok model parameters tuning for designed damper

Magnetorheological dampers have been the interest of many researchers for a few decades for the reason of being an effective and rapidly progressing technology in the field of semi-active controlled suspension. The dynamic behaviour of these devices with nonlinear hysteresis is quite a complicated phenomenon. Hence, this paper aims at the design, modelling and simulation of a custom-made MR damper for a two-wheeler vehicle. The Kwok model has been chosen to mathematically model the MR damper. The model parameters have been optimised by minimizing the error difference between experimental and model-generated force results. A PID control is designed to control the damper effectively depending on the deflection of the damper. The two-wheeler vehicle modelled with four degrees of freedom is coupled with a mathematical model of MR damper in front and rear suspension. Further, the dynamic analysis has been performed in MATLAB/Simulink considering random road input for different velocities and current input conditions. The improved performance of MR damper was observed in suppressing road irregularities using a PID controller. As an implementation part of the work, the developed damper has been implemented in a two wheeler vehicle for performance evaluation at on-road testing conditions. The results showed significant improvement in damper performance with increment of constant current controlling MR dampers.

Road type-based driving cycle development and application to estimate vehicle emissions for passenger cars in Guangzhou

Driving cycles are important parameters to estimate vehicle emissions. However, most previous driving cycles, which were developed at the city scale or even national scale, cannot resolve the emission variations affected by road types and thus might introduce large uncertainties in the emission estimation. In this study, we proposed a new approach based on road type-based (RT-based) driving cycles to improve the estimation of vehicle emissions. As a case study, RT-based driving cycles for passenger cars were developed using more than 600,000 s of GPS data collected through on-road tests in Guangzhou. Results showed that driving cycles varied across road types (urban arterial road, highway, and other urban road), which featured varied velocities, acceleration, deceleration, and driving mode percentages. The urban arterial road had the lowest velocity (18.7 km/h), but the largest creeping mode proportion (61%). The other urban road had the largest acceleration and deceleration, while the highway had the highest average velocity (43.2 km/h) but the lowest acceleration and deceleration. Evaluations revealed that RT-based driving cycles could accurately depict separate driving patterns and emission factors on different road types. In comparison, city-level driving cycles and standard driving cycles typically overestimated emission factors of highways but underestimated those of other road types in Guangzhou. Consequently, emissions of light-duty gasoline passenger cars could be underestimated by 33% in the downtown and overestimated by approximately 25% in and around the highways. This study highlights the development of RT-based driving cycles to accurately estimate vehicle emissions and characterize their spatial variations.

State-of-the-Art of Establishing Test Procedures for Real Driving Gaseous Emissions from Light- and Heavy-Duty Vehicles

Air pollution caused by vehicle emissions has raised serious public health concerns. Vehicle emissions generally depend on many factors, such as the nature of the vehicle, driving style, traffic conditions, emission control technologies, and operational conditions. Concerns about the certification cycles used by various regulatory authorities are growing due to the difference in emission during certification procedure and Real Driving Emissions (RDE). Under laboratory conditions, certification tests are performed in a ‘chassis dynamometer’ for light-duty vehicles (LDVs) and an ‘engine dynamometer’ for heavy-duty vehicles (HDVs). As a result, the test drive cycles used to measure the automotive emissions do not correctly reflect the vehicle’s real-world driving pattern. Consequently, the RDE regulation is being phased in to reduce the disparity between type approval and vehicle’s real-world emissions. According to this review, different variables such as traffic signals, driving dynamics, congestions, altitude, ambient temperature, and so on have a major influence on actual driving pollution. Aside from that, cold-start and hot-start have been shown to have an effect on on-road pollution. Contrary to common opinion, new technology such as start-stop systems boost automotive emissions rather than decreasing them owing to unfavourable conditions from the point of view of exhaust emissions and exhaust after-treatment systems. In addition, the driving dynamics are not represented in the current laboratory-based test procedures. As a result, it is critical to establish an on-road testing protocol to obtain a true representation of vehicular emissions and reduce emissions to a standard level. The incorporation of RDE clauses into certification procedures would have a positive impact on global air quality.

Real Driving Emission Calibration—Review of Current Validation Methods against the Background of Future Emission Legislation

Reducing air pollution caused by emissions from road traffic, especially in urban areas, is an important goal of legislators and the automotive industry. The introduction of so-called “Real Driving Emission” (RDE) tests for the homologation of vehicles with internal combustion engines according to the EU6d legislation was a fundamental milestone for vehicle and powertrain development. Due to the introduction of non-reproducible on-road emission tests with “Portable Emission Measurement Systems” (PEMS) in addition to the standardized emission tests on chassis dynamometers, emission aftertreatment development and validation has become significantly more complex. For explicit proof of compliance with the emission and fuel consumption regulations, the legislators continue to require the “Worldwide Harmonized Light Duty Vehicle Test Cycle” (WLTC) on a chassis dynamometer. For calibration purposes, also various RDE profiles are conducted on the chassis dynamometer. However, the combination of precisely defined driving profiles on the chassis dynamometer and the dynamics-limiting boundary conditions in PEMS tests on the road still lead to discrepancies between the certified test results and the real vehicle behavior. The expected future emissions standards to replace EU6d will therefore force even more realistic RDE tests. This is to be achieved by significantly extending the permissible RDE test boundary conditions, such as giving more weight to the urban section of an RDE test. In addition, the introduction of limit values for previously unregulated pollutants such as nitrogen dioxide (NO2), nitrous oxide (N2O), ammonia (NH3) and formaldehyde (CH2O) is being considered. Furthermore, the particle number (for diameters of solid particles > 10 nm: PN10), the methane (CH4) emissions and emissions of non-methane organic gases (NMOG) shall be limited and must be tested. To simplify the test procedure in the long term, the abandonment of predefined chassis dyno emission tests to determine the pollutant emission behavior is under discussion. Against this background, current testing, validation, and development methods are reviewed in this paper. New challenges and necessary adaptations of current approaches are discussed and presented to illustrate the need to consider future regulatory requirements in today’s approaches. Conclusions are drawn and suggestions for a robust RDE validation procedure are formulated.

Alternative Exhaust Emission Factors from Vehicles in On-Road Driving Tests

On-road driving tests are performed to determine the emission of harmful exhaust compounds from vehicles. These primarily include carbon dioxide, nitrogen oxides, and particle number. However, there is a lack of indicators that combine the first three substances that are the most important in assessing the environmental aspects of vehicles. The purpose of this article is to indicate the possibility of assessing emissions in real driving conditions from light-duty and heavy-duty vehicles of different categories. In order to do so, a portable emissions measurement system (PEMS) and an instrument for measuring the particle number were used. The tests were carried out on routes designed to comply with the requirements and regulations laid down in the European Union legislation. On-road emissions of carbon dioxide, nitrogen oxides and particle number have been determined. Factors have been determined as the multiplication of these compounds for each vehicle category in three phases of the test: urban, rural, and motorway. A new way of assessing emissions from vehicles using new factors has been proposed.

Vibration of a cryomodule’s coupler during road transportation: Multibody analysis and experimental validation

The road transportation of critical components for cryogenic cryomodules is a challenging task. Indeed, the shipping and the handling of fundamental sub-assemblies can expose these components to harmful dynamic loads that can jeopardize their structural integrity. This article has the purpose of developing a finite element multibody model capable of assessing the acceleration on a test coupler for a cavity of the Single Spoke Resonator 1 subjected to a typical road transportation trip. A multibody model consisting of rigid bodies and finite element–imported flexible bodies has been created allowing a comparison of the simulated and experimental acceleration. Afterwards, an experimental on-road test, whose set-up is described in this article, has been carried out at Fermilab with instrumented components. Being able to effectively simulate and validate the dynamic effects on such sub-assemblies makes it possible, for the future, to simulate more complex structures subject to dynamic loadings, such as the entire cryomodules during shipping. Furthermore, the results from the simulations can be used to guide the design of new suspension systems suitable for the reduction mitigation of structural vibration during the road transportation of cryomodules.