Developed in the frame of the European Clean Sky 2 program, the RACER High Speed Helicopter Demonstrator of Airbus performed its maiden flight on April 25th, 2024. In the continuity of the previous high-speed demonstrator X3 (1st flight in 2010) the RACER is a 7/8t (15000 / 18000 lb) class compound helicopter powered by two SHE Aneto-1X engines, including a wing and two propellers. The tail rotor is removed as the two propellers control the yaw axis by differential thrust. At flight 07, with its initial default settings, it reached a true airspeed of 227 kts in level flight, exceeding its objective of 220 kts.

Eglin, Paul, Embacher, Martin, Desvigne, Damien, Roca-Leon, Enric

Flap-Lag Stability Analysis of RACER in High-Speed Flight conditions

F-0081-2025-0226

5/20/2025

By its seventh flight after the first take-off, the RACER (Rapid And Cost-Effective Rotorcraft) demonstrator smoothly reached the targeted 220kts speed in stabilized forward flight, validating the high-speed compound architecture developed by Airbus Helicopters in the frame of Clean Sky 2 programme. During the flight envelope exploration, the dynamic behavior of the main rotor was carefully assessed, by monitoring the vibratory loads and validating its aeroelastic stability. Particular care was taken to validate the predicted stability domain of the Dual Rotor phenomenon, a particular case of flap-lag coupling associated with high-speed flight conditions. This paper presents the most significant results shaping the success of RACER flight test campaign. After having introduced the theoretical background and the associated analytical equations, the simulation framework based on the comprehensive analysis tool STORM is presented to discuss the numerical resolution of the stability

Skladanek, Yan, Coisnon, Remi, Ferullo, David

Fatigue Analysis of Motorcycle Rear Swing Arm on Different Road Surfaces

2024-32-00464/18/2025

The rear swing arm, a crucial motorcycle component, connects the frame and wheel, absorbing the vehicle’s load and various road impacts. Over time, these forces can damage the swing arm, highlighting the need for robust design to ensure safety. Identifying potential vulnerabilities through simulation reduces the risk of failure during the design phase. This study performs a detailed fatigue analysis of the swing arm across different road conditions. Data for this research were collected from real-vehicle experiments and simulation analyses, ensuring accuracy by comparing against actual performance. Following CNS 15819-5 standards, road surfaces such as poorly maintained, bumpy, and uneven roads were tested. Using Motion View, a comprehensive multi-body dynamic model was created for thorough fatigue analysis. The results identified the most stress-prone areas on the swing arm, with maximum stress recorded at 109.6N on poorly maintained roads, 218.3N on bumpy surfaces, and 104.8N on

Chiou, Yi-Hau, Hwang, Hsiu-Ying, Huang, Liang-Yu

Prediction Method of Strength Robustness Affected by Arc Welding Sectional Dimensions

2024-32-00384/18/2025

The arc welding process is essential for motorcycle frames, which are difficult to form in one piece because of their complex shapes, because a single frame has dozens of joints. Many of the damaged parts of the frames under development are from welds. Predicting the strength of welds with high reliability is important to ensure that development proceeds without any rework. In developing frames, CAE is utilized to build up strength before prototyping. Detailed weld shapes are not applicable to FE models of frames because weld shapes vary widely depending on welding conditions. Even if CAE is performed on such an FE model and the evaluation criteria are satisfied, the model may fail in the actual vehicle, possibly due to the difference between CAE and actual weld bead geometry. Therefore, we decided to study the extent to which the stresses in the joint vary with the variation of the weld bead geometry. Morphing, a FE modeling method and design of experiment method, was utilized to

Hada, Yusuke, Sugita, Hisayuki

Analysis of the Effect of Combination Frame Flexibility on Weave Modes

2024-32-00494/18/2025

The weave mode of a motorcycle is known to be affected by the flexibility of the vehicle frame. The weave mode has been shown to be more unstable in the 10-DOF model than in the 4-DOF model. However, it is not clear why the weave mode would be unstable, given the six different frame flexibilities. In this study, the authors analyzed the stability of the weave mode in a 4-DOF model when the same was integrated with two types of frame flexibilities. In the vehicle specifications used in the analysis, the combination of the bending flexibility of the front forks and the torsional flexibility of the main frame destabilizes the weave mode. The analysis results show that the phase delay of the front tire lateral force is caused by the phase delay of the steering angle. The combined bending flexibility of the front forks and the torsional flexibility of the main frame results in a large phase lag in the steering angle.

Haraoka, Reiya, Katayama, Tsuyoshi, Yoshino, Takahiko

Impact of the Wind on the Hovering Performance of Stabilized Payload Lifting with a Single Tethered Fixed-Wing Aircraft

F-0080-2024-0035

5/7/2024

Over the last 90 years, many concepts of lifting payload with a single tethered fixed-wing aircraft have been proposed. In this concept, an airplane flies along a quasi-circular flight path and the payload should remain at the center of this circle. The main challenge encountered has been payload stability in hover (i.e., when the payload is fixed in space and the aircraft flies along a quasi-circular path above). In calm conditions, lengthening the tether to reach two or three kilometers (1.5 mile) has been proven to stabilize the payload in an orbit with a radius of the order of 1 meter (3 ft). However, the presence of wind has shown a drastic reduction in payload stability. At the end of the 1990s, a patent proposed to add a thruster-based stabilization device onto the payload but no further studies explored such a concept. This study proposes a new concept inspired by the former. The main difference lies in the addition of a reel-in mechanism to control and stabilize the payload in

Doguet, Maxime, Rancourt, David

Surface Mount On-Blade Optical Telemetry System

F-0080-2024-1219

5/7/2024

AAM concepts use multiple distributed electric motors driving propellers and rotors to augment or directly generate lift and propulsive forces. Several current concepts incorporate separate drive systems for providing vertical lift, for takeoff and landing, and propulsive thrust for wing-borne cruising flight. Measurement of loads and performance on these rotating systems is very important in both the design and development stage, as well as for certification use and ultimately supporting HUMS monitoring. However, providing instrumentation in the rotating frame and extracting their associated measurements is often problematical, as it requires some means for both power and signals to bridge the rotating interface between the blade of the rotor/propeller and the fixed frame (fuselage) system. This paper describes work conducted to leverage prior CDI development of a novel optical telemetry/instrumentation system to create a prototype unit that can support ground and flight tests

McKillip, Robert

Low Noise Helicopter Operations Recommendations to Improve Helicopter Acceptance

F-0080-2024-1223

5/7/2024

This paper presents activities performed in the frame of MOTUS, a DGAC-funded research project, to better understand and reduce annoyance of helicopter operations. It focuses on the operational context of La Réunion island where local authorities intend to define concrete measures to answer multiple complaints from the population. In parallel with ongoing research towards a better understanding of short- and long-term annoyance thanks to both laboratory and field studies, the paper presents an in-depth analysis of helicopter operations in the area. Furthermore, specific recommendations on low noise operations are proposed to local operators in order to reduce their noise footprint and improve helicopter acceptance.

Caillet, Julien, Ruaud, Elise, Guntzer, Frédéric, Dieumegard, Pierre

Experimental Evaluation of Metro Rail Bogie Frame through Bench Testing

2024-26-03251/16/2024

Bogie frame is a main skeleton and structural member in railway system which is carrying all the loads such as Suspensions, Axles, wheels, car body, Motor, Gear box etc. The frame is subjected the exceptional and service stresses in Vertical, Longitudinal, Lateral and twist directions throughout the service life which should be withstand for a life span of 30 years without failure. The objective of this work is to estimate the structural integrity of the Metro rail bogie frame .This paper is the outcome of bench testing of metro rail bogie frame with the application of multiaxial loading in static and dynamic campaign through which stress data is collected with strain gauge sensors and correlated with the FEA results at design stage. This helps to verify and evaluate the design and validate the quality of metro rail frame as per the requirement specified in EN13749 European standard in early design stages.

Tormal, Uday Bapurao

Cab RLDA using VI & MI approach: A Co-Simulation of ADAMS & FEMFAT Lab VI/MI

2024-26-00511/16/2024

The current approach of hybrid RLDA is typically incapable of providing accurate dynamic loads coming on cab at chassis-to-cab load transfer locations, primarily due to following two reasons. Firstly, all of the model parameters of the vehicle, which is put on the four post, are not known. Secondly, MBS (Multi-body System) Cab model is multi degree of freedom with rigid bodies, flex bodies, contacts and non-linear force elements. Therefore, if the system identification is to be performed manually it becomes an arduous and humanly impossible task. Towards generating an accurate dynamic loads on cab, an approach using FEMFAT LAB - VI & MI has been developed which involves a two-step process: a) Generating MBS excitation by back calculating from measured frame response - VI (Virtual iterations). b) Fine tuning modelling parameters to match measured cab response - MI (Model Improvement). To execute the VI & MI approach for calculating dynamic loads on cab through 4-poster & 7-poster

Singh, Prempal, PRASAD, TEJ

Analytical tool for Design and Optimization of Double Isolation Mounting System for Electric Powertrain

2024-26-01251/16/2024

As the world rapidly moves from IC engine powered vehicles to the 'more sustainable' Electrified Vehicles, the Powertrain Mounting System needs to be re-engineered to meet refinement requirements of customer. Electric vehicles are quieter but due to lack of "masking effect", are sensitive to minor disturbances that are perceived to be objectionable by passengers. Also, E-powertrains are lighter, produce higher torque at low rpms & operate at higher rpms which calls for different countermeasures for mounting systems compared to conventional single isolation 3-point mounting system as used in IC engines. Double Isolation Mounting System, where powertrain is connected to an auxiliary mass (sub frame/cradle) via mounts, which is suspended to the vehicle body via cradle bushes results in 12 rigid body modes, 6 for each mass, is highly effective in lowering the transmission of vibration at high frequencies. This paper discusses 12 DOF analytical tool developed to rapidly analyze Powertrain

Verma, Shemon, Jayachandran, Suresh kumar, Mane, Yogiraj, Paua, Ketan, Vellandi, Vikraman

Countermeasures for Low Frequency Boom noise Reduction in Electric Vehicle

2024-26-02141/16/2024

Electric vehicles are much quieter than IC engine powered vehicles due to less mechanical components and absence of combustion. The lower cabin noise in electric vehicles make customers sensitive to even small disturbance in vehicle. Road boom noise is one of the major concerns to which the customers are sensitive in electric vehicles. The test vehicle is a front wheel driven compact SUV powered by electric motor. In normal plain road, noise levels are acceptable but when the vehicle has been driven on coarse road, the boom noise is perceived, and the levels are objectionable. Multi reference Transfer path Analysis (MTPA) is conducted to identify the path through which maximum forces are entering the body. Based on MTPA, modifications are proposed on the suspension bushes and the noise levels were assessed. Operational deflection shape (ODS) analysis is conducted on entire vehicle components like suspension links, sub frame, floor, roof, and doors to identify the deflection pattern of

S, Nataraja moorthy, Rao, Manchi, Raghavendran, Prasath, Selvam, Ebinezer

Active-Learning method : An effective way to generate ground truth data to test & validate ADAS functions

2024-26-03641/16/2024

In today’s autonomous industry, Machine learning plays an important role in development of various functions for self-driving vehicles. The learning models are trained using data, and their performance is determined by the quality of data they get trained on. For autonomous driving, sometimes, we don't have valid data and our model doesn't know what to do. As a result, the models must be trained on as much as diverse data as possible to make them efficient to deal with unusual situations in the actual world. Huge amount of unlabeled data is collected by cars moving around, equipped with multiple sensors to capture the surrounding environment in a frame. It becomes difficult to annotate each data manually and find data frame with more information. Therefore, automated methods are needed to identify and extract the most informative data from collected ones. Active learning is a powerful data selection technique which improves data efficiency for learning models. In Active Learning, the

Katariya, Rashmi, Kumari, Anita

Lightweighting of Two-Wheeler Frame with CAE - Multi Domain Optimization (MDO)

2024-26-02611/16/2024

Lightweighting in the automotive industry without the use of finite element methodologies is now inconceivable. With the development and enhancement of various CAE tools available in the market, CAE-driven optimization has become part of the product development cycle. Using a variety of CAE techniques in a lightweight optimization process can significantly reduce product development lead time with good results. Traditional light weighting can be done through different iterative approaches with different manual inputs from cross-domain teams, which is usually time consuming and leads to repeated analyses, etc. The current method describes the case of a multi-domain optimization (MDO) approach involving E-Motorcycle frame weight reduction while taking into account various important cross-domain load cases using CAE methodologies. For frame optimization, the most important loads - stiffness, durability/strength (Normal & Abusive), and NVH (Modes & Vibration) - were taken into account, as

S, Vishnu, kakanur, Ashok, U PE, Manjunatha, Bhat, Sachin, POOJARY, KIRAN, V N, Kishor

Vehicle Dynamics Simulation Correlation : Impact of Flexible Tyre and Flexible Frame in Comfort Prediction of Two Wheelers Motorcycles and Scooters

2024-26-00531/16/2024

For any two wheeler vehicle development, rider and pillion comfort while driving the vehicles over different kinds of road perturbations holds high importance. Designing a vehicle for comfort starts at the very beginning of its layout definition through vehicle geometric parameters, key hardpoints, mass-inertia distribution of subsystems and suspension characteristics. There is a need for highly reliable simulation models for comfort predictions as any change in layout during subsequent design stages is a very costly affair. Accurately predicting comfort using a full vehicle model is a challenging task though as it depends on how realistic the Simulation Model is to that of actual vehicle. While suspension stiffness and damping characteristics remain critical parameters for the comfort, selection of tyres are known to hold equal importance in vehicle comfort. The details to which the tyres are captured in the simulation model and the formulation of tyre interaction with roads in a

Govindula, Srikanth, Pandey, Pradyumn, Saraswat, Udit, Mishra, Ashish

Localisation of Ultra-short Sound Emissions from Automotive Components by Using the Sound Field Scanning Method

2025-01-00925/5/2023

Design verification and quality control of automotive components require the analysis of the source location of ultra-short sound events, for instance the engaging event of an electromechanical clutch or the clicking noise of the aluminium frame of a passenger car seat under vibration. State-of-the-art acoustic cameras allow for a frame rate of about 100 acoustic images per second. Considering that most of the sound events introduced above can be far less than 10ms, an acoustic image generated at this rate resembles an hard-to-interpret overlay of multiple sources on the structure under test along with reflections from the surrounding test environment. This contribution introduces a novel method for visualizing impulse-like sound emissions from automotive components at 10x the frame rate of traditional acoustic cameras. A time resolution of less than 1ms eventually allows for the true localization of the initial and subsequent sound events as well as a clear separation of direct from

Rittenschober, Thomas

Excavator exterior noise contribution analysis using angle-based operational acoustic load synthesis.

2025-01-00625/5/2023

Since earth moving machines (EMM) are subject to exterior noise (EN) regulations, OEMs need to develop mitigation solutions from an early design stage. It is challenging to predict solution effectiveness at early design stage. Excavators are distinct compared to other EMM as their upper frame rotate while keeping lower frame fixed. ISO 6395(2) or EC/2000/14(1) require EMMs to follow specific operating maneuvers where noise sources change their position, directivity, and speed along the operating cycle. These conditions pose challenges in performing noise contribution analysis as a function of angular position and operating condition. Authors successfully demonstrated Acoustic source quantification and contribution analysis for linearly moving EMMs. However, excavator pose data processing challenges due to angular motion. This work demonstrates the use of frequency domain ASQ for operational acoustic source quantification and use of frequency domain virtual prototype sub structuring

Vesikar, Prasad Balkrishna, Haynes, Timothy, Aquino Arriaga, Adrian Antonio, Drabison II, John, Chaduvula, Prasanna

The applications of Acoustic Black Holes to attenuation of Coach/Bus Frame Structure Vibrations

2025-01-00655/5/2023

Abstract An acoustic black hole (ABH) is a structure whose cross-sectional thickness decreases exponentially to zero, and the phase velocity and group velocity of wave propagation in those structure acoustic black holes decrease as the thickness decreases until they are zero. ABH produce some very magical physical phenomena. For example, because the wave velocity decreases to zero, the wave can never reach the center of the ABH, so the wave propagation in the acoustic black hole has neither refraction nor reflection; that is to say the vibration wave will not go through the acoustic black hole. As a result, the wave energy is concentrated in the center of the ABH. The arrangements of those acoustic black holes in the structures could change the directions of the vibrational wave propagation in the structures at NVH engineers’ wills. These amazing phenomena could play a magical role in reducing structural vibration, structural noise radiation and structure-borne noise. Basic structures

Huang, Xianli

Thin, Stretchable Biosensors Could Make Surgery Safer

TBMG-464939/1/2022

A research team developed bio-inks for biosensors that could help localize critical regions in tissues and organs during surgical operations. The ink is biocompatible and provides a user-friendly design with workable time frames of more than one day. Simultaneous recording and imaging could be useful during heart surgery in localizing critical regions and guiding surgical interventions such as a procedure for restoring normal heart rhythms.

Vehicle Feature Recognition Method Based on Image Semantic Segmentation

2022-01-01653/29/2022

In the process of truck overload and over-limit detection, it is necessary to detect the characteristics of the vehicle's size, type, and wheel number, etc. In addition, in some vehicle visual load recognition systems, the vehicle load can be calculated by detecting the vibration frequency of specific parts of vehicle or the change in the length of the suspension during the vehicle's forward process. Therefore, it is very important to quickly and accurately identify vehicle features through the camera. This paper proposes a vehicle feature recognition method based on image semantic segmentation and Python, which can identify the length, height, number of wheels and vibration frequency at specific parts of the vehicle based on the vehicle driving video captured by the roadside camera. The process of vehicle recognition is as follows: First, build a convolutional neural network based on the image semantic segmentation model SegNet and use the data set to train it, and use the Python

Wang, Chu, Ding, Shousheng

Investigations of Honeycomb and Foam structures of Automotive Front rails During Frontal crashes and its affinity with Optimum Energy Absorption

2022-01-10493/29/2022

Energy dissipation in frontal crash of the vehicles normally occurs through the deformation in the engine compartment zone and especially on longitudinal front rails. In this article, the details of the crash tests is presented which involves an interpretation of the damage profiles and understanding the origin of the stiffness coefficients in main particular member which is front rails of a passenger vehicle. Moreover, the present experimental work is used to estimate the energy dissipated during deformation based on crush measurements. Furthermore, it explains the implementation of experimental test to investigate the influence of design characteristics on the deformation behavior of the proposed front rails. The current experimental work deals with the influences of geometric shape modifications of conventional steel members with flange configurations compared to honeycomb structures and structural foam with the same members length. The observations in this work led to conclude the

Elhussieny, Sayed Abbas, Oraby, Walid

Influence of Manufacturing Processes on the Structural behavior of Truck Frame Rail Sections

2022-01-09143/29/2022

The sequence of manufacturing processes involved in the making of ladder shaped truck frame rail assembly leave certain amount of manufacturing and assembly imperfections in the form of plastic deformation and residual stresses in some areas of frame rail ‘C’ sections. The plastic deformation and the resulting residual stress should not be allowed to cross the safer limit as it would affect the structural behaviour of the frame rail while interacting with the externally induced loading stresses from extreme road operating conditions. If the combined stress level crosses the yield limit of the frame material, it may lead to premature failure of frame rail much before it gives the expected life. One such manufacturing induced premature failure in a truck frame rail assembly during proving ground trials was studied in detail using experimental analyses and presented in this paper. As part of this study, the local material crowding due to plastic deformation occurring at certain sections

K, Chinnaraj, KR, Balaji, Gopal, Gopi

Driveline Parking Brake Test Procedure for Medium Duty Vehicles

J2690_202110 (Current)

10/28/2021

This SAE Recommended Practice establishes uniform test procedures for friction based parking brake components used in conjunction with hydraulic service braked vehicles with a gross vehicle weight rating greater than 4500 kg (10 000 lb). The components covered in this document are the primary actuation and the foundation park brake. Various peripheral devices such as application dashboard switches or indicators are not included. These test procedures include the following: a Brake Related Tests 1 Brake Functional Performance 2 Brake Dynamic Torque Performance 3 Brake Corrosion Resistance 4 Brake Endurance with Torque 5 Brake Endurance without Torque 6 Vibration Resistance 7 Brake Ultimate Static Load 8 Brake Lining Wear Adjuster Function b Actuation Related Tests 1 Mechanical Actuator Functional Performance 2 Mechanical Actuator Endurance 3 Mechanical Actuator Quick Release 4 Mechanical Actuator Ultimate Load 5 Spring Apply Actuator Functional Performance 6 Spring Apply Actuator

Truck and Bus Hydraulic Brake Committee

SCV Chassis Performance Optimization through Parametric Beam Modelling & Simulation

2021-28-018310/1/2021

In automotive product development, design and development of the chassis plays an important role since all the internal and external loads pass through the vehicle chassis. Durability, NVH, Dynamics as well as overall vehicle performance is dependent on the chassis structure. Even though passenger vehicle chassis has a ladder frame or a monocoque construction, small commercial vehicle chassis is a hybrid chassis with the cabin welded to the ladder frame. As mileage is critical for sale of SCVs, making a light-weight chassis is also important. This creates a trade-off between the performance and weight which needs to be optimized. In this study, a parametric beam model of the ladder frame & the cabin of the vehicle is created in COMSOL Multiphysics. The structure has been parameterized into the long member & crossmember geometry and sections. The model calculates the first 12 natural frequencies, global stiffness, and weight. It has been validated and further used for optimization study

THANAPATI, ALOK Ranjan, Bhalerao, Mihir, Deshmukh, Chandrakant, Krishnan, Hareesh

Brake Groan Noise Investigation and Optimization Strategy for Passenger Vehicles

2021-26-03019/22/2021

Groan is a low frequency noise generated when moderate brake pressure is applied between the surfaces of the brake disc and the brake pad at a low-speed condition. Brake groan is often very intense and can cause large numbers of customer complaints. During a groan noise event, vehicle structure and suspension components are excited by the brake system and result in a violent event that can be heard and felt during brake application. The cause of noise is friction variation of stick-slip phenomenon between friction material and disc. This paper discusses the approach for prediction and mitigation of brake groan noise for passenger vehicles having disc brakes. To identify the brake groan noise frequency, vehicle testing with operating condition for reproducing the groan noise is carried out and also impact frequency response analysis is performed to identify natural frequency of each chassis component like brake, suspension stud, lower control arm, knuckle etc. The finite element corner

Doundkar, Vikas, Iqbal, Shoaib

Representing SUV as a 2D Beam Carrying Spring-Mass Systems to Compute Powertrain Bounce Mode

2021-01-11168/31/2021

Accurate prediction of in-vehicle powertrain bounce mode is necessary to ensure optimum responses are achieved at driver’s touch points during 4post shake or rough road shake events. But, during the early stages of vehicle development, building a detailed vehicle finite element (FE) model is not possible and often powertrain bounce modes are computed assuming the powertrain to be a stand-alone unit. Studies conducted on FE models of a large SUV with body on frame architecture showed that the stand-alone approach overestimates the powertrain bounce mode. Consequently, there is a need for a simplified version of vehicle model which can be built early on to compute powertrain modes. Previously, representing all the major components as rigid entities, simplified unibody vehicle models have been built to compute powertrain modes. But such an approach would be inaccurate here, for a vehicle with body on frame architecture due to the flexible nature of the frame (even at low frequencies). To

Maddali, Ramakanth, Mogal, Akbar Baig, Haider, Syed

A Comparative Study of Cradle and Sub Frame Type Powertrain Mounting System on Electric Vehicle

2021-01-10228/31/2021

The growing demand of fuel and cost saving on vehicle, today’s vehicle manufacturer are working on various weight reduction initiative in EV. Lighter weight vehicle have bigger challenges to meet NVH requirement. There are two types of EV called modified and adopted EV’s are commonly in use. The sub frame type of EV system comes under the category of modified EV. In this paper, a mounting system is studied and compared for a cradle type EV as well as sub frame or saddle type EV. MATLAB based optimization tools are used for parameter optimization. The focus is put on the optimization of mounting system location and stiffness for energy optimization, CoG and TRA-EA optimization. The best engine mounting system is compared and adopted based on simulation. 12 DOF studied to address high frequency resonance issues for a sub frame type EV. Finally robustness of the system is checked based on various simulation and optimization.

Deshmukh, Sagar, Hazra, Sandip

Calculation and Optimization Methods for the Dynamic Performances of a Power-Train-Subframe Mounting System

2021-01-06584/6/2021

A dynamic performance calculating model for a powertrain-subframe mounting system (PSMS) is presented. Calculation methods for determining the dynamic displacements of a powertrain center of gravity (CG), the dynamic displacements of a subframe CG and the dynamic reaction forces of each mount in a PSMS under ground and motor shake excitation are developed in this paper. An optimization procedure based on the genetic algorithm and SQP is developed for reducing resonance peaks of the reaction forces at mounts. A generic PSMS with three powertrain-subframe mounts and four subframe-body mounts is used to validate the optimization method. The optimization results demonstrate that the results using the optimization procedure can effectively reduce the reaction forces at mounts.

Fang, Zhiyuan, Zhen, Ran, Li, Ruilong

Felling Head Terminology and Nomenclature

J1272_202103 (Current)

3/1/2021

This SAE Standard is intended to describe the basic types of felling heads, including those with bunching capabilities, that are attachments to a self-propelled machine. Only the major components that are necessary to describe the functions of the felling head, and to apply the principles of the standard are included. Illustrations used are not intended to include all existing felling heads or to describe any particular manufacturer’s variation.

MTC4, Forestry and Logging Equipment

Nissan's 2021 Rogue is a COVID beater

21AUTP02_142/1/2021

Nissan staff truly pulled out the stops to get the all-new 2021 Rogue into the market during the global pandemic. Rogue is the company's best-selling product in North America, by far - a testament to a well-considered overall package that designers, engineers and product planners have steadily evolved and improved since the model's launch in 2007. Now in its third generation (coded T33), the latest Rogue is underpinned by Nissan's C/D-segment architecture that shares more geometries with Sentra, itself a vastly upgraded and improved vehicle for 2021. “Last March, I was reviewing our program schedules and it looked like everything was going to get delayed due to Covid,” said Chris Reed, executive VP of R&D at Nissan Technical Center in Farmington, Mich. “At this time, we had delays in other programs due to a ‘development overload’ situation between suppliers and prototypes. The hatches were being battened down.

Brooke, Lindsay

Enhancement of Longitudinal Energy Absorption Efficiency in FMVSS 301

2020-01-12254/14/2020

While active safety has become a focus of attention, passive safety protocols are still being updated, and evaluation standards are becoming stringent worldwide. This paper focused on FMVSS 301, the North American regulation for rear impacts. Due to an offset impact with deformable barrier, it is challenging to control bending modes of rear frames. Furthermore, there is a considerable difference in load paths to the left and right frames, and the amount of bending deformation experienced by the frame on the non-collision-side, which does not directly contact with the barrier, is low. The purpose of this research was to enhance rear-frame energy absorption efficiency in such collisions. To achieve this goal, this research focused on enhancement of deformation mode of the rear frames, and also minimizing the difference in their input loads. For the enhancement of deformation mode, the number and arrangement of collapse points were optimized, and multi-stage bending mode with a high level

Hasegawa, Atsushi, Fujii, Takayuki, Matsuura, Norikazu, Shimizu, Tomohiro

Chassis Lightweighting Hole Placement with Weldline Evaluation

2020-01-04934/14/2020

Vehicle weight driven design comes amid rising higher fuel efficiency standard, and must meet the criteria - pass Proving ground test events that is equivalent customer usage. CAE Fatigue analysis for proving ground (CFP) is behind a success push to digitally simulate vehicle durability performance in high fidelity. The need for vehicle weight reduction often arises late in vehicle development phases when CAE Methods, time, and tangible cost effective opportunities are limited or non-existent. It is necessary to deploy a new CAE Method to identify opportunities for light-weighting hole placement in Chassis structures to deliver a cost effective light-weighting opportunity with no impact on fatigue life. The successful application of this methodology is on truck frame, which is key structural parts for vehicle chassis to support body and suspension and powertrain. By means of artificially adjusting the magnitude of load time history and material fatigue properties S-N curve, fatigue

Song, Gavin

Wireless Movement-Tracking System Uses Low-Power Radio Frequency Signals

TBMG-359872/1/2020

A system called Marko uses signal reflections to provide scientists and caregivers with valuable insights into people's behavior and health. Marko transmits a low-power radio-frequency (RF) signal into an environment. The signal will return to the system with certain changes if it has bounced off a moving human. Novel algorithms then analyze those changed reflections and associate them with specific individuals. The system then traces each individual's movement around a digital floorplan. Matching these movement patterns with other data can provide insights about how people interact with each other and the environment.

Adding Context to Full-Motion Video for Improved Surveillance and Situational Awareness

20AERP02_032/1/2020

Today's intelligence, surveillance, and reconnaissance (ISR) platforms integrate state-of-the-art technologies and subsystems into airborne platforms intended to observe, detect, identify, and neutralize threats. Full motion video (FMV) sensors are essential assets and are routinely used on fixed-wing, rotary-wing, and manned and unmanned platforms to provide real-time situational awareness with minimal latency. Ultimately, FMV is invaluable for helping operators answer the what, where, when, and why of a scenario. These sensors, which are easy and relatively inexpensive to integrate and deploy, support mission-critical tasks such as target detection and analysis. This may include tracking and pattern recognition-for example, FMV is particularly well suited for long stand-off ranges such that a target is not aware that they are being observed.

Study on the Quantitative Relationship between Static Stiffness and Modal Parameters of an Aluminum Space Frame

10-04-02-00071/27/2020

In this article, the quantitative relationship between the static stiffness, lightweight factor, and modal parameters of an aluminum space frame was investigated. Modal theory calculation and finite element method were employed in the analysis. Fifty modal parameters were extracted from the finite element model of the frame to calculate the bending stiffness, torsional stiffness, and lightweight factor of the frame. The deviations of the bending stiffness, torsional stiffness, and lightweight factor obtained from the modal theory and the finite element theory were found to be 0.91%, 1.72%, and 1.71%, respectively. It indicates that these two methods have similar accuracy. It was confirmed that the sum of each order modal compliance could be used to calculate the static compliance of the aluminum space frame. The first-order bending mode was found to be the corresponding mode order, which made the largest contribution to the bending stiffness. This method is also applicable for

Wang, Zhenhu, Xia, Erli, Chen, Ziming, Xue, Zhigang, Li, Luoxing

Simulation of Ice Particle Breakup and Ingestion into the Honeywell Uncertified Research Engine (HURE)

2019-01-19656/10/2019

Numerical solutions have been generated which simulate flow inside an aircraft engine flying at altitude through an ice crystal cloud. The geometry used for this study is the Honeywell Uncertified Research Engine (HURE) which was recently tested in the NASA Propulsion Systems Laboratory (PSL) in January 2018. The simulations were carried out at predicted operating points with a potential risk of ice accretion. The extent of the simulation is from upstream of the engine inlet to downstream past the strut in the core and bypass. The flow solution is produced using GlennHT, a NASA in-house code. A mixing plane approximation is used upstream and downstream of the fan. The use of the mixing plane allows for steady state solutions in the relative frame. The flow solution is then passed on to LEWICE3D for particle trajectory, impact and breakup prediction. The LEWICE3D code also uses a mixing plane approximation at the boundaries upstream and downstream of the fan. A distribution of particle

Rigby, David L., Wright, William, Flegel, Ashlie, King, Michael

Structure-Borne Prediction on a Tire-Suspension Assembly Using Experimental Invariant Spindle Forces

2019-01-15416/5/2019

Road induced noise is getting more and more significant in context of the electrification of the powertrain. The automotive industry is seeking for technologies to predict the contribution of vehicle components upfront, early in the development process. Classical Transfer Path Analysis (TPA) is a well-established technique that successfully identifies the transmission paths of noise and vibration from different excitation sources to the target responses. But it has a drawback: it requires the physical availability of the full vehicle. To achieve shorter development cycles, to avoid costly time-consuming design iterations and due to the limited availability of prototypes, engineers derived a method that addresses these requirements. Component-based TPA is a relatively new structure borne substructuring approach that allows to characterize the source excitation by a set of equivalent loads (blocked forces) independently from the receiver structure and to predict its behavior when coupled

Ortega Almirón, Jesús, Bianciardi, Fabio, Corbeels, Patrick

Plastic Bearings Redefine the Wheelchair

TBMG-345806/1/2019

For wheelchair users, the feeling of uneven ground can seem all too familiar. Determined to make ride discomfort a thing of the past, Israel-based SoftWheel has completely reinvented the wheel for a float-like experience.

Interplay Between Optic Flow, Pilot Workload and Control Response During Aggressive Approach to Hover Maneuvers for Three Vertical Lift Vehicle Models

F-0075-2019-14645

5/13/2019

This work proposes a novel relationship between pilot workload and optic flow during visual approach-to-land maneuvers. A simulation experiment was conducted at NASA Ames Vertical Motion Simulator (VMS) to evaluate the workload associated with operating two candidate Army Future Vertical Lift (FVL) vehicles: a compound (coaxialrotor and push-prop) vehicle, and a tilt-rotor vehicle. The UH-60 was included in the evaluation as a baseline reference. Sixteen experienced military pilots flew aggressive visual approaches terminating in a hover while providing Bedford workload ratings in real time. No approach or hover guidance was displayed to the pilot. The out-the-window (OTW) environment (front and chin monitors) was digitally recorded and the optical flow of each video frame computed. Prior work identified a mathematical relationship between pilot workload and the combination of display error rate and stick rate during compensatory tracking tasks. The current work extends this

Bachelder, Dr., Aponso, Bimal, Godfroy-Cooper, Dr.

The Blue Edge - Blade Continuation

F-0075-2019-14546

5/13/2019

Airbus is certifying new H160 helicopter, first serial application of the Blue EdgeTM rotor system, easily recognizable with its double leading edge swept shape. The reduction of the blade-vortex interaction noise has been the main driver of this design, studied since the 1990s, in collaboration between DLR, ONERA and Eurocopter (since become Airbus). From the project ERATO (Etude d'un Rotor Aeroacoustique Technologiquement Optimise = aeroacoustically optimized rotor), the Blue EdgeTM blade design became the trademark of the last rotor generation whose the history is summarized in Ref. 1. In 2014, a first extrapolation of this type of shape has been developed and tested in the frame of BluecopterTM demonstrator as described in Ref. 2. The five-bladed bearingless rotor flew on EC135 in order to explore a low tip speed within new optimized eco airfoils and twist distribution. At the same time, new studies of Blue EdgeTM design has been performed with other objectives: keeping the shape

Hirsch, Jean-François, Alfano, David, Cranga, Paul, Gareton, Vincent, Guntzer, Frédéric