Browse Topic: Test equipment and instrumentation

Items (2,508)
ABSTRACT V-shaped hulls for vehicles, to mitigate buried blast loads, are typically formed by bending plate. Such an approach was carried out in fabricating small test articles and testing them with buried-explosive blast load in Southwest Research Institute’s (SwRI) Landmine Test Fixture. During the experiments, detailed time dependent deflections were recorded over a wide area of the test article surface using the Dynamic Deformation Instrumentation System (DDIS). This information allowed detailed comparison with numerical simulations that were performed with LS-DYNA. Though in general there is good agreement on the deflection, in the specific location of the bends in the steel the agreement decreases in the lateral cross section. Computations performed with empirical blast loads developed by SwRI and by more computationally intensive ALE methods in LS-DYNA produced the same results. Computations performed in EPIC showed the same result. The metal plate was then bent numerically so
Walker, James D.Chocron, SidneyMoore, Thomas Z.Bradley, Joseph H.Carpenter, Alexander J.Weiss, CarlGerlach, Charles A.Grosch, Donald J.Grimm, MattBurguess, Victor W.
ABSTRACT For most standards bodies, the validation and maturation process is dependent on motivated members of the standards community to develop reference systems or components and to provide the governing body with the necessary data and details to support maturing a given specification or set of specifications. Although this has worked well for other standards bodies, the VICTORY Standards Support Office (VSSO) recognized early that validation would be key in rapidly defining usable specifications for the Army ground vehicle community. Understanding the importance of validating specifications, the VSSO formally defined a validation process that is used to aid in maturing the VICTORY Standard Specifications. This paper will focus on explaining the formalized validation process that is applied to the VICTORY Standard Specifications
Dennis, DoyleSaylor, KaseWilliams, NikiaSiddapureddy, VenuFairburn, Brian
ABSTRACT This paper describes novel experimental methods aimed at understanding the fundamental phenomena governing the motion of lightweight vehicles on dry, granular soils. A single-wheel test rig is used to empirically investigate wheel motion under controlled wheel slip and loading conditions on sandy, dry soil. Test conditions can be designed to replicate typical field scenarios for lightweight robots, while key operational parameters such as drawbar force, torque, and sinkage are measured. This test rig enables imposition of velocities, or application of loads, to interchangeable running gears within a confined soil bin of dimensions 1.5 m long, 0.7 m wide, and 0.4 m deep. This allows testing of small-scale wheels, tracks, and cone or plate penetrators. Aside from standard wheel experiments (i.e., measurements of drawbar force, applied torque, and sinkage during controlled slip runs) two additional experimental methodologies have been developed. The first relies on high-speed
Senatore, CarmineMacLennan, JamieJayakumar, ParamsothyWulfmeier, MarkusIagnemma, Karl
ABSTRACT The first part of this paper will outline the conception of the testing apparatus (Figure 1), along with its operation and preliminary results. The second part of the paper will discuss a new methodology used to correlate the dependence of crack growth rate for strain crystallizing natural rubbers in terms of tearing energy. The tearing energy which depends on the type of elastomer, geometry and stress strain behavior of a particular specimen demonstrates a direct correlation with the crack growth rate at different R-ratios (= min tearing energy/max tearing energy). Figure 1 Schematic of the testing apparatus
Kujawski, DanielDiStefano, DarenBradford, William
ABSTRACT Tools have been developed to compare the dynamic deformation of vehicle hulls as they undergo blast-testing with numerical simulations. These tools allow quantitative comparisons and measurements over a wide area of the hull surface, rather than point comparisons as have been performed in the past. The experimental measurements are performed with the Dynamic Deformation Instrumentation System (DDIS) that was developed for TARDEC. Numerical simulations of the test article attached to Southwest Research Institute’s Landmine Test Fixture were performed with LS-DYNA using an empirical blast-loads model. The specific example highlighted in this paper is the deformation by blast testing of a hull component
Walker, James D.Grosch, Donald J.Chocron, SidneyGrimm, MattCarpenter, Alexander J.Moore, Thomas Z.Weiss, CarlBigger, Rory P.Mathis, James T.McLoud, Katie
ABSTRACT The Integrated Survivability System Integration Laboratory (ISSIL) developed at the U.S. Army Tank-Automotive Research, Development, and Engineering Command (TARDEC) is a tool which enables and enhances the integration of Soldier survivability technology suites. TARDEC utilized the ISSIL to bridge the gap between concept and realization of the survivability demonstrator vehicle built on MTV 1083 A1P2 platform. The ISSIL was a critical tool for enabling the integration of mechanical, electrical, data, and networking components as well as for validating the system integration through Soldier usability trials. This paper describes how the ISSIL advanced the RDECOMs comprehensive systems engineering process throughout the modeling, analysis, design, development and testing of the demonstrator vehicle
Siddapureddy, VenuFountain, NathanSanders, DavidBudzik, Stacy
ABSTRACT The Optical Warhead Lethality Sensor Suite (OWLSS) was designed specifically for tracking dense, fast fragment fields generated in warhead arena testing. OWLSS is an optimized hardware/software solution for measuring correlated properties of detonating warhead fragment distributions. The OWLSS automated track algorithm returns time-dependent 3D position, velocity, size, aerodynamic drag, and mass estimates for each fragment tracked. These data products fill a significant gap in our ability to characterize munitions for weapon effectiveness modeling. Furthermore, the system is modular and can be reconfigured for many tracking applications. In this paper, we present an overview of legacy arena measurement techniques, an overview of the OWLSS optical tracking approach, and we discuss how OWLSS can be employed to collect test data needed to improve the survivability of armored vehicles. Citation: J. P. Burke, Jr, J. Roe, S. F. Henke, B. P. Walker, W. Koons, “An Enhanced Optical
Burke, James P.Roe, JeffreyHenke, Steven F.Walker, Bradley P.Koons, William A.
In the quest for reduced cost and shorter development times for fuel cell systems in industrial applications, two major issues arise. First, the electrochemical behavior of fuel cell systems is inherently difficult to predict. Second, testing fuel cell systems is resource intensive. These issues compound: Setting up an accurate model of a fuel cell system incurs long testing periods for model validation. Further, it does not guarantee acceptable results outside the tested range or for other membrane electrode assembly compositions. To mitigate these two major issues an X in the Loop concept is proposed. Essentially, this is the direct integration of the test sample, here a single fuel cell, into the modelling environment of the whole system. In practice, two strategies with different levels of integration are defined. The first strategy consists of initially deducing the operating parameters of the sample cell from the fuel cell system model. Then, setting them to the sample cell in
Oswald, TancrèdeWeiss, LukasWensing, Michael
To gain high efficiencies and long lifetimes, polymer electrolyte membrane fuel cell systems require precise control of the relative humidity of the cathode supply air. This is usually achieved by the use of membrane humidifiers. These are passive components that transfer the product water of the cathode exhaust air to humidify the supply air. Due to the passive design, controllability is achieved via a bypass. It is possible to use map-based control strategies to avoid the use of humidity sensors. Such map-based control requires deep insights into the humidifier behavior in all possible thermodynamic operating states, including various water loads. This paper focuses on typical operating conditions of heavy-duty application at high load, specifically on the occurrence of liquid water in the cathode exhaust gas, which has not been sufficiently investigated in the literature yet. In order to simulate these conditions, we built a test rig with an optically accessible single-channel set
Mull, SophieWeiss, LukasWensing, Michael
In recent years, deposit formation in fuel systems for heavy-duty engines, using drop-in fuels, have become increasingly common. Drop-in fuels are particularly appealing because they are compatible with existing engines, allowing for higher proportions of alternative fuels to be blended with conventional fuels. However, the precipitation of insoluble substances from drop-in fuels can result in fuel filter clogging and the formation of internal injector deposits, leading to higher fuel consumption and issues with engine drivability. The precise reasons behind the formation of these deposits in the fuel system remain unclear, with factors such as operating conditions, fuel quality, and fuel contamination all suggested as potential contributors. In order to reproduce and study the formation of internal injector deposits, for heavy-duty engines under controlled conditions and to facilitate a more precise comparison to field trials, a novel injector test rig has been developed. This newly
Pach, MayteHittig, HenrikTheveny, ArnaudKusar, HenrikHruby, Sarah
In this work we demonstrate the influence of different refined TCR refining diesel fuels on emission, power and efficiency in comparison to reference Diesel fuel (homologation fuel for Euro 6 emission testing), hydrotreated vegetable oil (HVO) and a blend of poly(oxymethylene)dimethyl ether (OME3) with reference Diesel. The emission characteristics of such TCR fuels used in a production type Diesel engine with modern common rail system has up to now not been tested. The comparison was performed at an engine test bench equipped with a Hatz 4H50 TIC direct injection common rail Diesel engine. For different engine operation points exhaust gas emissions and particulate matters were measured and the results analyzed
Seeger, JanTaschek, Marco
This document defines performance standards which mechanical fiber optic cable splices must meet to be accepted for use in aerospace platforms and environments
AS-3 Fiber Optics and Applied Photonics Committee
This document defines performance standards which fiber optic cable splices must meet to be accepted for use in aerospace platforms and environments
AS-3 Fiber Optics and Applied Photonics Committee
This document provides recommended best practice methods and processes for the in-service inspection, evaluation and cleaning of all physical contact (PC) fiber optic interconnect components (termini, alignment sleeves and connectors), test equipment and test leads for maintainers qualified to the approved aerospace fiber optic training courses developed in accordance with ARP5602 or ARINC807. This document also provides a decision-making disposition flowchart to determine whether the fiber optic components are acceptable for operation. For definitions of individual component parts refer to ARP5061
AS-3 Fiber Optics and Applied Photonics Committee
This SAE Aerospace Recommended Practice (ARP) describes a method of conducting an endurance test using contaminated air when the applicable specification requires non-recirculation of the contaminants. The objective of the test is to determine the resistance of the engine mounted components to wear or damage caused by the contaminated air. The method described herein calls for non-recirculation of the contaminants and is intended to provide a uniform distribution of the contaminant at the inlet to the Unit Under Test (UUT). The UUT may require the use of a hydraulic fluid for actuation of components within the test unit. Contamination of the test hydraulic fluid is not part of this recommended practice. If contaminated hydraulic fluid is required by the applicable test specification, refer to MAP749
AC-9 Aircraft Environmental Systems Committee
Arraid LLC Phoenix, AZ 480-699-3047 JamesHilken@solidstatedisks.com
Vehicle chassis design can take great advantage from a virtual design approach, as it helps tackle the complexity of modern machines, bringing benefits in performance, development cost, and lead-time. For specific applications such as construction or defense vehicles, the simulation design chain may lack significant input model bricks due to the physical limitations of existing test equipment which limit their ability to characterize the large components and extreme loading conditions (high loads, large torques, extreme slip angles. etc.). Michelin SIMIX proposes / develops an innovative solution to fill the gap by combining physical real world measured data with virtual measurements, allowing the creation of digital models relevant to the full usage perimeter
Andrews, MikeMaclanders, JustinKhayat, CédricLeymin, FrédéricSpetler, Frédéric
This document defines cables that are used to provide electrical power for U.S. Department of Defense avionics support and test equipment
AGE-3 Aircraft Ground Support Equipment Committee
Manually checking the quality of components or products in industry is labor-intensive for employees and error-prone on top of that. The Fraunhofer Institute for Mechatronic Systems Design IEM is unveiling a solution that provides total versatility in this area. In an it’s OWL supported collaboration with Diebold Nixdorf and software specialist verlinked, Fraunhofer IEM has created a combination of collaborative robot (cobot), AI-based image analysis and IoT platform. The system frees employees from having to perform visual inspections and can be incorporated into all kinds of testing scenarios. The Fraunhofer researchers presented a demonstrator of the cobot/IoT platform at the 2024 Hannover Messe Trade Show in February
Accurate estimation of vehicle energy consumption plays an important role in developing advanced energy-saving connected automated vehicle technologies such as Eco Approach and Departure, PHEV mode blending, and Eco-route planning. The present study developed a reduced-order energy model with second-order response surfaces and torque estimation to estimate the energy consumption while just relying on the drive cycle information. The model is developed for fully electric Chevrolet Bolt using chassis dynamometer data. The dyno test data encompasses the various EPA test cycles, real-world, and aggressive maneuvers to capture most powertrain operating conditions. The developed model predicts energy consumption using vehicle speed and road-grade inputs for a drive cycle. The accuracy of the model is validated by comparing the prediction results against track and road test data. The developed model was able to accurately predict the energy consumption for track drive cycles within the error
Goyal, VasuDudekula, Ahammad BashaStutenberg, KevinRobinette, DarrellOvist, GrantNaber, Jeffery
This article aims to conduct a comprehensive performance analysis of various propeller configurations and motors for uncrewed aerial vehicles. The experimental method is used for this study through the performance analysis of the motors and propellers at various conditions. In this study, the test rig has been manufactured specially to test the propeller and motor configuration as per the standard to obtain the thrust at various supplied voltage. This study proved that the increase in the size of propeller leads to increase in the thrust, as well as it can be used for specific applications of the drone like racing drone. It reveals that the maximum diameter of a propeller is 14 inches, which produces the thrust in the range of 2400 g to 361 g depending on motor capacity compared to the other size of the propellers. The novelty of the work is to analyze the performance of propellers and motors for optimization and application of drones through experimental methods. This method can be
Ajay Vishwath, N.C.Balaji, K.Vaishampayan, VibhavPatil, DeepMehta, ParshvaDonde, Gaurangi
Simulation company rFpro has already mapped over 180 digital locations around the world, including public roads, proving grounds and race circuits. But the company's latest is by far its biggest and most complicated. Matt Daley, technical director at rFpro, announced at AutoSens USA 2024 that its new Los Angeles route is an “absolutely massive, complicated model” of a 36-km (22-mile) loop that can be virtually driven in both directions. Along these digital roads - which were built off survey-grade LIDAR data with a 1 cm by 1 cm (1.1-in by 1.1 in) X-Y grid - rFpro has added over 12,000 buildings, 13,000 pieces of street infrastructure (like signs and lamps), and 40,000 pieces of vegetation. “It's a fantastic location,” Daley said. “It's a huge array of different types of challenging infrastructure for AVs. You can drive this loop with full vehicle dynamic inputs, ready to excite the suspension and, especially with AVs, shake the sensors in the correct way as you would be getting if you
Blanco, Sebastian
The shape and energy distribution characteristics of exhaust pulse of an asymmetric twin-scroll turbocharged engine have a significant impact on the matching between asymmetric twin-scroll turbines and engines, as well as the matching between asymmetric twin scrolls and turbine wheels. In this article, the exhaust pulse characteristics of an asymmetric twin-scroll turbocharged engine was studied. Experiments were conducted on a turbine test rig and an engine performance stand to determine the operation rules of exhaust pulse strength, turbine flow parameters, turbine isentropic energy, and turbine efficiency. The results showed that the exhaust pulse strength at the inlets of both the small and large scrolls continuously decreased with the increase of engine speed. And the flow parameters at the inlets of the small and large scrolls exhibited a “ring” or “butterfly” shape with the change of expansion ratio depending on the pressure deviation of the extreme points at the troughs on both
Wu, LiangqinJin, JianjiaoWang, JieZhang, Chenyun
Airplane manufacturers running noise tests on new aircraft now have a much cheaper option than traditional wired microphone arrays. And it’s sensitive enough to help farmers with pest problems. The wireless microphone array that one company recently created with help from NASA can locate crop-threatening insects by listening for sound they make in fields. And now, it’s making fast, affordable testing possible almost anywhere
The study demonstrates the possibility and in particular the method to derive the efficiency of the entire fuel cell power system by measuring specific data of the recirculation path of the anode circuit of a fuel cell system. The results demonstrate the capabilities of the existing test rig and enable investigations on the suitability of auxiliary components. This study focuses on the hydrogen recirculation path equipped with multiple sensors and a needle valve to enable the required operating conditions of the fuel cell. Running a startup load profile without reaching the equilibrium state at all steps, the dynamic of the system and the requirements to the sensor parameters, such as sampling rate and precision, was seen. Additionally, it became obvious that the recirculation pump used is oversized, but a load point shift compensated this artifact. In detail, the stoichiometry and the efficiency of the entire system was evaluated. It was seen that the hydrogen concentration is
Allmendinger, FrankMartin, BenediktSchmidtmann, Marlen
Homologation is an important process in vehicle development and aerodynamics a main data contributor. The process is heavily interconnected: Production planning defines the available assemblies. Construction defines their parts and features. Sales defines the assemblies offered in different markets, where Legislation defines the rules applicable to homologation. Control engineers define the behavior of active, aerodynamically relevant components. Wind tunnels are the main test tool for the homologation, accompanied by surface-area measurement systems. Mechanics support these test operations. The prototype management provides test vehicles, while parts come from various production and prototyping sources and are stored and commissioned by logistics. Several phases of this complex process share the same context: Production timelines for assemblies and parts for each chassis-engine package define which drag coefficients or drag coefficient contributions shall be determined. Absolute and
Jacob, Jan D.
In electrified vehicles, auxiliary units can be a dominant source of noise, one of which is the refrigerant scroll compressor. Compared to vehicles with combustion engines, e-vehicles require larger refrigerant compressors, as in addition to the interior, also the battery and the electric motors have to be cooled. Currently, scroll compressors are widely used in the automotive industry, which generate one pressure pulse per revolution due to their discontinuous compression principle. This results in speed-dependent pressure fluctuations as well as higher-harmonic pulsations that arise from reflections. These fluctuations spread through the refrigeration cycle and cause the vibration excitation of refrigerant lines and heat exchangers. The sound transmission path in the air conditioning heat exchanger integrated in the dashboard is particularly critical. Various silencer configurations can be used to dampen these pulsations. This paper compares the acoustic and thermodynamic performance
Saur, LukasHeidegger, PatrickNaeger, ChristophBecker, Stefan
The automotive industry is continuously evolving, demanding innovative approaches to enhance testing methodologies and preventively identify potential issues. This paper proposes an advanced test approach in the area of the overall vehicle system including the steering system and powertrain on a Road to Rig test bench. The research aims to revolutionize the conventional testing process by identifying faults at an early stage and eliminating the need to rely solely on field tests. The motivation behind this research is to optimize the test bench setup and bring it even closer to real field tests. Key highlights of the publication include the introduction of an expanded load spectrum, incorporating both steering angle and speed parameters along the test track. The load includes different route and driving profiles like on a freeway, overland and city drive in combination with the steering angles. Furthermore, for the first instance, specific driving manoeuvres, including slalom driving
Kopp, LennartHarfmann, PatrickNiederberger, LucasSchwämmle, TimmKley, Markus
Squeak and rattle (SAR) noise audible inside a passenger car causes the product quality perceived by the customer to deteriorate. The consequences are high warranty costs and a loss in brand reputation for the vehicle manufacturer in the long run. Therefore, SAR noise must be prevented. This research shows the application and experimental validation of a novel method to predict SAR noise on an actual vehicle interior component. The method is based on non-linear theories in the frequency domain. It uses the Harmonic Balance Method (HBM) in combination with the Alternating Frequency/Time Domain Method (AFT) to solve the governing dynamic equations. The simulation approach is part of a process for SAR noise prediction in vehicle interior development presented herein. In the first step, a state-of-the-art linear frequency-domain simulation estimates an empirical risk index for SAR noise emission. Critical spots prone to SAR noise generation are located and ranked. In the second step, the
Rauter, AndreasUtzig, LukasWeisheit, KonradMarburg, Steffen
The axle system is a major contributor for road induced vehicle interior noise. However, it is challenging to characterize the NVH performance of the axle system because it is coupled with both the tire/wheel and the body structure. In this article, we introduce a global approach to control the NVH performance of the axle system. The force transmissibility based on the blocked force concept was defined as the indicator of NVH performance of the axle system. A hybrid method combining test and simulation was developed to assess the intrinsic NVH performance of the axle system. The force transmissibility of the axle system is the blocked force generated by the axle system at the body mounting points with a unit of input force on the wheel. It can be simulated easily by FEM with rigid boundary conditions. However, measuring the blocked forces of the axle system is much more complex because it requires very stiff boundary conditions, which are difficult to realize on a realistic test rig
Wang, ShanjinGagiu, Constantin
When traveling in an open-jet wind tunnel, the path of an acoustic wave is affected by the flow causing a shift of source positions in acoustical maps of phased arrays outside the flow. The well-known approach of Amiet attempts to correct for this effect by computing travel times between microphones and map points based on the assumption that the boundary layer of the flow, the so-called shear layer, is infinitely thin and refracts the acoustical ray in a conceptually analogy to optics. However, in reality, the turbulent nature of both the not-so-thin shear layer and the acoustic emission process itself causes an additional smearing of sources in acoustic maps, which in turn causes deconvolution methods based on these maps – the most prominent example being CLEAN-SC – to produce certain ring effects, so-called halos, around sources. In this paper, we intend to cast some light on this effect by describing our path of analyzing/circumventing these halos and how they are linked to the
Puhle, ChristofMeyer, AndyDöbler, Dirk
Liebherr Machines Bulle SA (LMB) designs and produces High-quality diesel engines, injection systems as well as hydraulic components. Liebherr has an Acoustic End of Line (AEOL) system on serial test benches. All engines are measured, and noises are evaluated by operators. This subjective evaluation leads to dispersion on the evaluations, particularly for whining noise. To ensure customer satisfaction, Liebherr wishes to define a new methodology to find a quantitative and objective criterion to set a robust engine noise compliance standard. This new methodology is based on near field microphone measurement of an engine run-down. First, whining noise signatures are extracted from the raw signal. Secondly, psychoacoustic indicators are calculated on the extracted signatures. Thresholds are then established to validate engine deliveries. Finally, this process combining advanced signal processing and psychoacoustics is automated using the Ansys Sound Python library in mass production. All
Akrout, SamirDenisse, RobinDendievel, ClementFineschi, Fabio
This SAE Recommended Practice is intended as a guide toward standard practice and is subject to change to keep pace with experience and technical advances. This document provides standardized laboratory tests, test methods and equipment, and requirements for lighting devices covered by SAE Recommended Practices and Standards. It is intended for devices used on vehicles less than 2032 mm in width. Tests for vehicles larger than 2032 mm in overall width are covered in SAE J2139. Device specific tests and requirements can be found in applicable SAE technical reports
Test Methods and Equipment Stds Committee
The winged body reusable launch vehicle needs to be tested and evaluated for its functionality during the pre-flight preparation at the runway. The ground based checkout systems for the avionics and the actuator performance testing during pre-flight evaluation are not designed for rapid movement. This new kind of launch vehicle with solid rocket first-stage and winged body upper-stage demands the system testing at Launchpad and at the runway. The safety protocol forbids the permanent structure for hosting the checkout system near runway. The alternative is to develop a rapidly deployable and removable checkout system. A design methodology adopting conventional industrial instrumentation systems and maintaining mobility is presented. This paper presents the design and development of a mobile checkout system for supporting the ground pre-flight testing during autonomous flight landing trials
V, Vivekanand
Testing aircraft antennas is challenging since optimal tests are made after antenna installation. Aircraft are often taken to anechoic antenna test facilities which create long lead times, transportation hassle, and very high costs. Portable alternatives exist but often have compromised testing fidelity. Innovators at the NASA Glenn Research Center have developed the PLGRM system, which allows an installed antenna to be characterized in an aircraft hangar. All PLGRM components can be packed onto pallets, shipped, and easily operated
Remember that party where you were swinging glow sticks above your head or wearing them as necklaces? Fun times, right? Science times, too. Turns out those fun party favors are now being used by a University of Houston researcher to identify emerging biothreats for the United States Navy
In order to efficiently predict and investigate a vehicle’s vertical dynamics, it is necessary to consider the suspension component properties holistically. Although the effects of suspension stiffness and damping characteristics on vertical dynamics are widely understood, the impact of suspension friction in various driving scenarios has rarely been studied in both simulation and road tests for several decades. The present study addresses this issue by performing driving tests using a special device that allows a modification of the shock absorber or damper friction, and thus the suspension friction to be modified independently of other suspension parameters. Initially, its correct functioning is verified on a shock absorber test rig. A calibration and application routine is established in order to assign definite additional friction forces at high reproducibility levels. The device is equipped in a medium-class passenger vehicle, which is driven on various irregular road sections as
Deubel, ClemensSchneider, Scott JarodProkop, Günther
Validation plays a crucial role in any Electronic Development process. This is true in the development of any automotive Electronic Control Unit (ECU) that utilizes the Automotive V process. From Research and Development (R&D) to End of Line (EOL), every automotive module goes through a plethora of Hardware (HW) and Software (SW) testing. This testing is tedious, time consuming, and inefficient. The purpose of this paper is to show a way to streamline validation in any part of the automotive V process using Python as a driving force to automate and control Hardware-in-the-loop (HIL) / Model-in-the-loop (MIL) / Software-in-the-loop (SIL) validation. The paper will propose and outline a framework to control test equipment, such as power supplies and oscilloscopes, load boxes, and external HW. The framework includes the ability to control CAN communication signals and messages. A visual Graphical User Interface (GUI) has also been created to provide simplified operation to the user
Rosiewicz, BrandonLink, Bravin
Polymer electrolyte membrane (PEM) fuel cells will play a crucial role in the decarbonization of the transport sector, in particular for heavy duty applications. However, performance and durability of PEMFC stacks is still a concern especially when operated under high power density conditions, as required in order to improve the compactness and to reduce the cost of the system. In this context, the optimization of the geometry of hydrogen and air distributors represents a key factor to improve the distribution of the reactants on the active surface, in order to guarantee a proper water management and avoiding membrane dehydration. To this purpose, the adoption of CFD simulation tools can provide a useful insight into the physical phenomena which determine the efficient operation of the fuel cell (e.g. transport of mass, heat, species, electrons and ions, electrochemical reactions, water formation and removal), providing a valuable support for the design and the optimization of the
Bulgarini, MargheritaDella Torre, AugustoMontenegro, GianlucaBaricci, AndreaGrimaldi, AmedeoMereu, RiccardoMarocco, LucaCollaku, AldoSavoldi, Laura
Simulators are essential part of the development process of vehicles and their advanced functionalities. The combination of virtual simulator and Hardware-in-the-loop technology accelerates the integration and functional validation of ECUs and mechanical components. The aim of this research is to investigate the benefits that can arise from the coupling of a steering Hardware-in-the-loop simulator and an advanced multi-contact tire model, as opposed to the conventional single-contact tire model. On-track tests were executed to collect data necessary for tire modelling using an experimental vehicle equipped with wheel force transducer, to measure force and moments acting on tire contact patch. The steering wheel was instrumented with a torque sensor, while tie-rod axial forces were quantified using loadcells. The same test set has been replicated using the Hardware-in-the-loop simulator using both the single-contact and multi-contact tire model. The simulation apparatus is composed of a
Veneroso, LucaCapitani, RenzoAlfatti, FedericoAnnicchiarico, ClaudioFarroni, FlavioSakhnevych, Aleksandr
Symbolic code execution is a powerful cybersecurity testing approach that facilitates the systematic exploration of all paths within a program to uncover previously unknown cybersecurity vulnerabilities. This is achieved through a Satisfiability Modulo Theory (SMT) solver, which operates on symbolic values for program inputs instead of using their concrete counterparts. However, in complex code bases, this approach faces significant limitations, such as program path explosions or unavailable dependencies, which can result in conditions that the SMT solver cannot reason about. Consequently, SMT solvers are often considered as too costly to implement for automotive testing use cases and are rarely employed within this domain. In contrast, fuzz testing has recently gained traction in the automotive industry as an invaluable testing technique for identifying previously unknown vulnerabilities. Its initial setup is straightforward and typically yields useful findings. However, achieving
Vinzenz, NicoOka, Dennis Kengo
A ban on Per- and Polyfluorinated Substances (PFAS) has enforced automobile companies to find alternatives to current R1234yf refrigerant. One such natural substitute, R290 (propane), is becoming popular with automotive manufacturers and suppliers due to its high performance and efficiency. However, due to its high flammability, R290 is not allowed in the cabin evaporator/condenser in order to ensure the safety of the driver and passenger. This requires the design of a novel indirect Heat Flux Management System (HFMS) with coolant as a working fluid to transfer heating to cabin and powertrain cooling components. The design of the heat pump system confines flammable R290 refrigerant to a hermitic compact box to avoid leakages. This paper aims to investigate the performance and efficiency of a new R290 refrigerant-based indirect heat pump system. The system is tested on a test bench, and the results are compared to an indirect heat pump system with R1234yf refrigerant. The study and
Gupta, RaghavSaraswat, RohanGravelle, Aled
Rubber mount as an important element can reduce the vibration transmitted by the engine to the frame. And under small and medium deformation conditions, Mooney-Rivlin model can well describe the mechanical properties of the rubber mount. The accurate parameters of Mooney-Rivlin model are the basis of describing the mechanical properties of the mount. First, taking powertrain rubber mount as the research object, the influence of preload on the static characteristics of the mount is studied by the preload test rig. Second, Particle swarm optimization-Back propagation neural network (PSO-BPNN) model and Back propagation neural network (BPNN) model was established. After the number and step length of hidden layer neurons were determined, the prediction accuracy of the two models is compared. Then, combined with finite element analysis and crow search algorithm, a parameter identification model considering preload is established, the constitutive parameters corresponding to preload and non
Sun, JiaweiZhao, RenfeiSun, HongjieMa, Qiang
A set of enthalpy difference test equipment is set up to test flow and heat exchange performance of chillers. The empirical correlations for the convective heat transfer coefficients on the coolant side and the refrigerant side are obtained by fitting the test data, and a two-particle lumped parameter model of the chiller is established. Based on this, the heat exchange performance of the chiller under different operating conditions is given. The effects of herringbone corrugated plate parameters, including angle, pitch, and depth, on flow and heat exchange performance of chillers under different flow rates are further studied. Using the Wilson plot method in test design, the thermal resistance of convective heat transfer on each side is separated from the total thermal resistance to calculate the convective heat transfer coefficient. In fitting the boiling convective heat transfer coefficient on the refrigerant side, various boiling behaviours within the two-phase zone are considered
Sun, MingKang, YingziWang, MengmengShangguan, Wen-Bin
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