Browse Topic: Tests and Testing

Items (24,183)
This paper presents the design of a novel intelligent monitoring platform for low and medium altitudes, aiming to offer a new solution for the development of intelligent equipment operating in this airspace. Current monitoring tasks are primarily performed by fixed-wing and multi-rotor UAVs, but these platforms face significant technical bottlenecks in flight endurance and monitoring precision. This research aims to address these deficiencies. The platform is based on a small-scale unmanned airship featuring a semi-rigid, hybrid lift-body structure. Improvements were made upon the traditional ellipsoidal hull; the hull profile was optimized using a geometric superposition method, introducing an aerodynamic camber line with a maximum camber (m) of 4% to enhance aerodynamic performance at small angles of attack. In terms of its energy system, the platform is powered by a purely electric energy system composed of solar panels and batteries; solar energy is used during the day, while
Song, ZiangGao, WenxuanCao, XiaochuanZheng, XingZhao, Chong
This article focuses on the problem of high labor cost, low processing efficiency and poor automation of the existing equipment in the postharvest processing of Chinese cabbage. It will design and produce an automated Chinese cabbage processing method called Smart Fresh Pack. Root removal, leaf removal, washing, loading, weighing, packaging and labeling functions were integrated, and smart dexterous intelligence was applied to core concepts and this can be used in the bulk production scenario of supermarkets in the city and countryside Compared with traditional assembly line equipment, obvious advantages in terms of structure, function and processing capacity: Key innovations include: Low-pressure air jet cleaning replaces water washing, which prevents a second contamination and weighing error due to surface moisture; pneumatic gripper and multi-DOF robotic arms combine to package and dynamically weigh simultaneously, streamlining these tasks; machine vision relies on an SSD
Chen, YuhuiZhang, YixuanRuan, JiaZhu, HuayunHe, LianzhengZhao, Ping
To address the growing demand for waste management, improve the efficiency and accuracy of waste classification, reduce costs, promote environmental protection and circular economy development, and solve environmental pollution and resource waste problems through technological innovation. This paper proposes an intelligent mobile waste classification and collection robot system. The system consists of a picking mechanical arm subsystem, a waste classification and collection subsystem, a self-moving chassis subsystem, and a solar tracking power generation subsystem. The picking mechanical arm subsystem actively collects waste through a mechanical arm combined with machine vision technology and deposits it into the waste classification device, while the waste classification and collection subsystem completes functions such as classification, compression, collection, and dumping, utilizing a navigation and positioning-driven chassis to achieve autonomous waste collection, simultaneously
Xia, YingZhu, HuabingJia, RuitongHe, YifanHou, WentaoFu, ShaozaoLin, Jiaoyang
AMS6885/5 is the Material Specification (MS) which defines the requirements of a unidirectional carbon fiber tape epoxy repair prepreg capable of curing under vacuum for repair of carbon fiber reinforced epoxy structures. It also defines the requirements of an epoxy film adhesive to be applied in a co-bonding process with the prepreg for solid laminate and sandwich bonding.
AMS CACRC Commercial Aircraft Composite Repair Committee
This test method covers procedures to qualitatively determine the visual and physical condition of a liquid organic coating component (pigmented base, base without pigment, curing solution, or thinner) in a container. Also covered is evaluation of the component container to determine any degradation.
AMS G8 Aerospace Organic Coatings Committee
While an enlarged lead time from risk notifications to collisions is widely acknowledged to facilitate safe driving, it remains challenging to effectively notify drivers of invisible risks and non-apparent risks coming from uncertain behaviors on the part of road users. The current study examined whether verbal notifications are able to assist early awareness of predictive risks. We also attempted to identify human and environmental factors that could possibly improve the effectiveness of predictive risk information. Twenty-eight licensed drivers participated in a public road test conducted in two different urban areas on 3 days. They drove predefined courses on which potential risk locations were identified prior to the test, using a sport utility vehicle equipped with an automatic verbal notification system triggered based on the distance to the potential risk locations. After passing through the locations each time, the participants were instructed to verbally evaluate the shift in
Maruyama, MasakiKoyama, KeiichiroEzaki, ToruSakamoto, JunichiSawada, YutaMatsuoka, Takahiro
Machina Labs recently closed its latest round of financing with $124 million, enough to develop a facility featuring up to 50 of its RoboCraftsman cells capable of producing thousands of complex structural assemblies for aerospace and defense customers - a list that already includes Lockheed Martin and the U.S. Air Force, among others. Founded in 2019, Machina Labs is a California-based company that seeks to reinvent metal manufacturing with a robot that uses artificial intelligence (AI) to rapidly form and assemble complex military grade structures directly from digital design files. RoboCraftsman is the company's manufacturing robot that leverages its proprietary “RoboForming” process to integrate multiple manufacturing processes - including metal forming, trimming, scanning, and heat treating - into a single containerized machine.
Army researchers recently developed a 3D-printable, easy-to-assemble drone designed to enhance intelligence, surveillance and reconnaissance capabilities. Army Research Laboratory, Adelphi, MD Researchers at the U.S. Army Combat Capabilities Development Command, or DEVCOM, Army Research Laboratory (ARL) harnessed bottom-up Soldier innovation to develop an experimental 3D-printed small unmanned aerial system, or drone, that was demonstrated at the inaugural U.S. Army Best Drone Warfighter Competition in Huntsville, Alabama. Known as the Soldier Portable Autonomous Reconnaissance Transitioning Aircraft, or SPARTA, the drone was developed at DEVCOM ARL in collaboration with Soldiers. By incorporating Soldier feedback early in the design process and leveraging ARL's world-class research facilities, researchers developed a 3D-printable, easy-to-assemble drone designed to enhance intelligence, surveillance and reconnaissance capabilities. ARL is actively working to partner the technology
This document describes a rigorous engineering test procedure that utilizes industry-accepted data collection and statistical analysis methods to determine the road load and to estimate the aerodynamic drag area of trucks and buses weighing more than 10000 pounds. The test procedure may be conducted on a test track or on a public road under controlled conditions and supported by extensive data collection and data analysis constraints. The estimated aerodynamic-drag-area result represents a single-speed and single-yaw-angle condition. Test results that do not rigorously follow the method described herein shall not be represented as an SAE J2978 result.
Truck and Bus Aerodynamics and Fuel Economy Committee
This specification covers a synthetic rubber in the form of sheet, strip, tubing, extrusions, and molded shapes. This specification should not be used for molded rings, compression seals, O-ring cords, and molded in place gaskets for aeronautical and aerospace applications without complete consideration of the end use prior to the selection this material.
AMS CE Elastomers Committee
Flow conditions on the road are quite different from the conditions used to develop vehicle aerodynamics. However, a significant amount of statistical data now exists that describes realistic road conditions. Some of these on-road flow characteristics can be replicated in wind tunnels. This paper reviews technical facilities designed to simulate on-road flow characteristics, such as turbulence intensity, turbulent length scales, and flow angle distribution. Reconstruction of a flow field that matches real road conditions is made possible by using active or passive turbulence generators within the wind tunnel. This review provides a comprehensive overview of these facilities, offering readers key insights into the challenges involved in replicating real-world flow conditions in wind tunnels.
Vondruš, JanVančura, Jan
To address the performance testing requirements of autonomous vehicles (AVs), this study proposes a model predictive control (MPC) algorithm specifically designed for low-ground-clearance test target vehicles (TTVs) to achieve trajectory tracking control. First, the kinematic model of the TTV is established, and its state-space equations are derived. An objective optimization function incorporating both error weighting and control weighting is designed. Simulation analysis reveals the influence of the control error weighting ratio (CEWR) on both straight-line and curved trajectory tracking performance: For straight-line tracking, increasing the CEWR from 10 to 25 reduces the overshoot, but increases the distance required to reach the target trajectory by 4.7%. A similar pattern is observed in curved trajectory tracking. To overcome the limitations of the fixed CEWR, an improved MPC algorithm integrating fuzzy control is proposed. This algorithm dynamically adjusts the CEWR in real time
Ji, ShaoboLu, YueqiLiao, GuoliangChen, ZhongyanLi, MengLyu, ChengjuZhang, Zhipeng
To establish the acceptance criteria for discontinuities as revealed by magnetic particle or liquid penetrant examination of aircraft utility parts as in 1.2.
E-25 General Standards for Aerospace and Propulsion Systems
Achieving an optimal balance between simulation accuracy and computational efficiency remains a central challenge in automotive aerodynamics. While the adoption of AI and machine learning (ML) methods in vehicle development is expected to grow significantly, the demand for highly scalable, computationally efficient, and accurate computational fluid dynamics (CFD) methods persists. The emergence of GPU (graphics processing unit) technology presents new opportunities to deliver cost-effective, high-fidelity, scale-resolving simulations to industrial users. A comprehensive evaluation of Simcenter STAR-CCM+’s parallel scalability and accuracy across extensive CPU and GPU resources was executed on the Frontier supercomputer at Oak Ridge National Laboratory (ORNL). Steady-state and transient aerodynamic scalability simulations were executed using the DrivAer notchback vehicle configuration. Simulation accuracy was evaluated through transient simulations employing the SST-DDES turbulence
Larsson, TorbjörnGrover, Ronald O.Landi, SimoneAltmann, PeterMcManus, LiamDowding, Steven
Aerodynamic interactions between two 30%-scale passenger vehicles in close proximity were examined experimentally in a large wind tunnel, with a focus on longitudinal separations up to two vehicle lengths, lateral separations up to one lane width, and combinations thereof. Part 1 of this paper described the longitudinal following (platooning) configurations of these results, while this paper concentrates on adjacent-lane influences and lateral-offset effects when platooning at a single separation distance. Test models were based on the DrivAer and Aero-SUV open-access geometries, each with slant-back (Notchback or Fastback) and square-back (Estateback) variants. This provided four distinct model pairings, not all of which were tested in each positional arrangement. Adjacent-lane results matched the trends from a smaller-scale study in a different wind tunnel using the same geometry pair, with small-but-distinct differences attributed to different blockage ratios in the two wind-tunnel
McAuliffe, BrianGhorbanishohrat, Faegheh
Demand for cost-effective automotive traction inverters requires improved power module packaging. This paper presents a packaging method using an epoxy composite insulator applied directly to the cold plate surface, replacing Direct Bonded Copper (DBC) and Active Metal Brazed (AMB) substrates. This integration removes the substrate-to-cold plate solder interface and eliminates two material layers from the thermal path. The epoxy composite demonstrates a dielectric strength greater than 60 kV/mm. Thermal resistance (junction-to-coolant) measured approximately 0.17 K∙cm2/W. Electrical characterization showed a relative permittivity of 3.9, which is lower than standard ceramics and results in reduced parasitic capacitance. Initial thermal cycling tests indicated no significant degradation in thermal or electrical performance. These results suggest the epoxy composite insulator could be a promising alternative for traction power modules.
Chen, YuMena-Garcia, JavierChen, HaoXiao, KeweiGupta, Man PrakashDegner, Michael
Aerodynamic wind noise is a critical challenge in modern automotive development, particularly with the rise of vehicle electrification and intelligent mobility, where cabin acoustic comfort is a key quality metric. While reliable, traditional methods like wind tunnel experiments and computational fluid dynamics (CFD) simulations are both costly and time-consuming. To address these challenges, we propose a novel Transformer-based framework for rapid and accurate wind noise prediction. Several model improvements, including the physical attention, geometry wave number embedding, hybrid FPS-random downsampling method and frequency separation output heads are properly employed to reduce the GPU memory cost and improve the prediction accuracy. This framework is pre-trained on a large-scale acoustic dataset of nearly 1,000 diverse vehicles generated using Improved Delayed Detached Eddy Simulation (IDDES). From a vehicle's point cloud coordinates, the model directly predicts the surface
Tang, WeishaoLiu, MengxinQin, LingDuan, MenghuaWang, ChengjunZhang, YufeiWang, Qingyang
Accurate detection and evaluation of kissing bonds in composite materials is essential to ensure the integrity of the component structure, but traditional NDT (non-destructive testing) methods struggle to identify imperfect bonds and zero-volume debonds. In this study, a vibration analysis method based on holography was applied to detect kissing bonds by monitoring the changes in natural frequencies of the same sample before and after fatigue loading. Both pristine and kissing bond samples were tested under identical conditions, and their vibration characteristics (natural frequency, amplitude, and mode shape) were measured using holography. The experimental results show for the intact sample exhibited no changes in natural frequency amplitude or mode shape after fatigue loading, confirming that the applied fatigue test did not affect the integrity of its adhesive layer. In contrast, for the sample with a kissing bond, after fatigue loading, the natural frequency decreased by up to 22
Gao, ZhongfangFang, SiyuanGerini-Romagnoli, MarcoYang, Lianxiang
Weather-strip sealing systems are critical to automotive closure performance, influencing water- and dust-tightness, aerodynamic noise control, and overall NVH quality. Conventional validation often relies on flat or straight JIG-based tests that inadequately represent the curved, angled, and non-uniform geometries of real closures such as doors, tailgates, hoods, roofs, and fixed or movable glass. This disparity limits the predictive accuracy of sealing performance in actual vehicles. This study proposes a vehicle-integrated validation framework that mirrors true geometric and contact conditions. The methodology combines finite element analysis (FEA) of both flat JIG and full-vehicle CAD geometries with experimental JIG tests, establishing a baseline for pressure distribution, compression load, and sealing contact behavior. A comparative analysis highlights significant deviations between flat-section predictions and vehicle-specific closure profiles. Results demonstrate that the
Ganesan, KarthikeyanSeok, Sang Ho
Towing imposes substantial efficiency penalties on both battery-electric vehicles (BEVs) and internal combustion engine (ICE) vehicles, reducing range by 30-50%. This paper presents a proof-of-concept embedded control architecture for distributed trailer propulsion that actively regulates drawbar force to reduce towing loads. Unlike proprietary e-trailer systems requiring specialized hardware, the proposed implementation demonstrates feasibility using commercial off-the-shelf (COTS) components and open-source software. The distributed architecture employs dual Raspberry Pi 4B single-board computers communicating via ROS 2 at 20 Hz. The trailer-mounted controller executes a Simulink-generated control node coordinating load cell acquisition (HX711 ADC), motor CAN bus telemetry, and throttle commands to a 5 kW BLDC traction motor powered by a 5 kWh LiFePO4 battery pack. A vehicle-mounted controller logs OBD-II/CAN validation data. The control pipeline implements cascaded EWMA/Hampel
Joshi, GauravAdelman, IanLiu, JunDonnaway, Ruthie
Wake effects modify the aerodynamic performance of a road vehicle when driving in traffic. Analysis of wind-tunnel measurements conducted in flows with wake characteristics, using a traffic-wake-simulation system, suggests that conventional uniform-wind performance coefficients can be scaled, using wake-flow-field information, to predict the influence of wake effects. This paper presents a flow-field-averaging method that estimates a dynamic-pressure correction and yaw-angle correction for application to uniform-wind data, to account for changes in performance due to wake effects. This first-order method is shown to provide reasonably-good accuracy when reverse correcting the wind-tunnel wake-effects measurements. Drag-coefficient data for light-duty-vehicle models, which showed wake effects exceeding 20%, were corrected to within 5% of uniform-wind values, while data for heavy-duty-vehicle models, which showed wake effects exceeding 15%, were corrected to within 2% of uniform-wind
McAuliffe, Brian
The braking performance of a vehicle at varying levels of road wetness is an important factor in collision reconstruction. Here we quantify the deceleration levels of two modern vehicles equipped with antilock brake systems (ABS) on a wetted asphalt surface with a high proportion of exposed, large-sized aggregates as the road naturally dried over time. We also compare our current results to prior tests on asphalt with a small proportion of small-sized aggregate. Two ABS-equipped vehicles were maximally braked on an asphalt road surface as the road naturally transitioned from a saturated wet state to a completely dry state. Road wetness was visually categorized from photographs taken during testing. Overall, we found that deceleration levels on wet asphalt were significantly less than deceleration levels on dry asphalt (average dry: 0.902g and 0.962g; average wet: 0.787g and 0.818g for the two vehicles). Within the wetness categories we used, there was either no significant difference
Ahrens, MatthewArnold, NikolasMiller, IanSiegmund, Gunter P.
In order to determine the on-board EDR data recording characteristics of a GM vehicle, a 2023 GMC Sierra Denali was tested in several Pedestrian Automatic Emergency Braking (P-AEB) scenarios. Using a variety of test tools, including the STRIDE robotic platform and its onboard data systems, a GPS/IMU installed in the vehicle, and several camera units, the vehicle was put into collision imminent scenarios in which the crash avoidance systems were actuated. The flags in the EDR data, the order in which EDR events were written, and the correlation between the EDR and data recorded by the aforementioned external acquisition systems were examined for each test case. Testing was done in both forward and reverse scenarios and at low speeds only. These results provide a picture of the current state of the additional data available in current EDRs installed on GM vehicles equipped with P-AEB capability, as well as an insight into the accuracy and meaning of that data which should prove
Bartholomew, MeredithArnett, MichaelGuenther, Dennis
This paper describes Waymo's Collision Avoidance Testing (CAT) methodology: a scenario-based testing method that evaluates the safety of the Waymo Driver Automated Driving Systems' (ADS) intended functionality in conflict situations initiated by other road users that require urgent evasive maneuvers. Because SAE Level 4 ADS are responsible for the dynamic driving task (DDT), when engaged, without immediate human intervention, evaluating a Level 4 ADS using scenario-based testing is difficult due to the potentially infinite number of operational scenarios in which hazardous situations may unfold. To that end, in this paper we first describe the safety test objectives for the CAT methodology, including the collision and serious injury metrics and the reference behavior model representing a non-impaired eyes on conflict human driver used to form an acceptance criterion. Afterward, we introduce the process for identifying potentially hazardous situations from a combination of human data
Kusano, KristoferBeatty, KurtSchnelle, ScottFavaro, FrancescaCrary, CamVictor, Trent
This paper reports on the Catesby Aero Research Facility (CARF), which began commercial operation in 2019, and summarizes facility characteristics and associated measurement technologies, with an emphasis on vehicle-mounted component-force measurement devices. CARF is a proving ground converted from a former railway tunnel approximately 2.74 km in length and surfaced with high-quality tarmac. The road-surface quality was specified to be comparable to that of SUBARU's proving ground and was achieved using established construction methods. The course is approximately straight with a small longitudinal grade. Key course specifications include an approximately 40 m2 blockage area, a 6 m road width (maximum 8.4 m), flatness σ < 0.5 mm, and a gradient of 0.57%. Relative to outdoor coast-down testing, the tunnel length enables continuous measurement to very low speeds, thereby improving repeatability. A six-component force sensor integrated into the hub unit enables on-road measurement of
Shimoyama, Hiroshi
When driving in traffic, the wakes of leading vehicles reduce the wind speed experienced by a following vehicle, lowering its drag relative to isolated driving. These wake effects can persist to large inter-vehicle distances, on the order of hundreds of meters, while lateral convection due to cross winds can influence vehicles in adjacent lanes. Wind tunnel testing was conducted at 30% scale for light- and heavy-duty-vehicle models in a large wind tunnel with a traffic-wake simulation system, expanding upon a previous study that examined only heavy vehicles. Three variants of the DrivAer model, four variants of the AeroSUV model, and three variants of a zero-emission heavy-duty-truck model were tested with a range of simulated wake conditions that varied the type, forward distance, and lane position of the wake-source vehicle(s), for a range of yaw angles up to 11°. Results show drag reductions of up to about 10% for the heavy-duty-truck model, and up to about 20% for the passenger
McAuliffe, BrianGhorbanishohrat, FaeghehBarber, Hali
The Stellantis North America Aero-Acoustic Wind Tunnel (AAWT) has been upgraded with a cutting-edge 5-belt Moving Ground Plane (MGP) system, featuring an 8.5-meter center belt and four Wheel Spinning Unit (WSU) belts with advanced coatings for durability and visibility. The expanded 9.4-meter turntable enables ±90° yaw and supports vehicles with wheelbases from 1800 mm to 4500 mm and weights up to 5000 kg, accommodating the full Stellantis North America product range. The original 2-stage boundary layer control system was retained, with new tertiary slots added for improved flow quality. A high-stiffness, six-component Horiba balance with integrated calibration weights and tractive force measurement ensures accurate and precise measurements. Facility enhancements include a 550 m2 building addition for equipment and vehicle prep, a dedicated compressor container for clean air supply, and a vehicle underbody wash booth for efficient cleaning. Commissioning confirmed that flow quality
Lounsberry, ToddLadouceur, BrentFadler, Gregory
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