Browse Topic: Pitch

Items (847)

An incremental coordinated control method for distributed drive electric vehicle through the anti-squat/lift/dive suspension

2025-01-8267

04/01/2025

In this paper, an incremental coordinated control method through anti-squat/lift/dive suspension is proposed based on and suited to a distributed drive electric vehicle with front and rear dual motors. The precise relationship between the suspension reaction force and the driving force of the wheel is derived as the control model through an in-depth analysis of the wheel motion and force. Through imposing the first-order dynamics, the proposed method not only provides the longitudinal speed control of the vehicle but also suppresses the longitudinal, vertical and pitch vibration of the vehicle. Simulation results show that the suspension reaction force formula derived in this paper is more suitable for dynamic conditions, and compared with the control method based on the simplified suspension anti-squat/lift/dive control model, the proposed method using the accurate control model has superior comprehensive control performance.

Feng, Cong, Wu, Guangqiang, Yang, Yuchen

Sensitivity Analysis of Virtual Crash Simulation Software Using Design of Experiments (DOE)

2025-01-8693

04/01/2025

This paper is a continuation of a previous effort to evaluate the post-impact motion of vehicles with high rotational velocity within various vehicle dynamic simulation softwares. To complete this goal, this paper utilizes a design of experiments (DOE) method. The previous papers analyzed four vehicle dynamic simulation software programs; HVE (SIMON and EDSMAC4), PC-Crash and VCRware, and applied the DOE to determine the most sensitive factors present in each simulation software. This paper will include Virtual Crash into this methodology to better understand the significant variables present within this simulation model. This paper will follow a similar DOE to that which was conducted in the previous paper. A total of 32 trials were conducted which analyzed ten factors. Aerodynamics, a factor included in the previous DOE, was not included within this DOE because it does not exist within Virtual Crash. The same three response variables from the previous DOE were measured to determine

Roberts, Julius, Civitanova, Nicholas, Stegemann, Jacob, Buzdygon, David, Thobe, Keith

Study on the Impact of Vehicle Pitch During Braking on Pedestrian Leg Injuries

2025-01-8741

04/01/2025

With the increasing prevalence of Automatic Emergency Braking Systems (AEB) in vehicles, their performance in actual collision accidents has garnered increasing attention. In the context of AEB systems, the pitch angle of a vehicle can significantly alter the nature of collisions with pedestrians. Typically, during such collisions, the pedestrian's legs are the first to come into contact with the vehicle's front structure, leading to a noticeable change in the point of impact. Thus, to investigate the differences in leg injuries to pedestrians under various pitch angles of vehicles when AEB is activated, this study employs the Total Human Model for Safety (THUMS) pedestrian finite element model, sensors were established at the leg location based on the Advanced Pedestrian Legform Impactor (APLI), and a corresponding vehicle finite element model was used for simulation, analyzing the dynamic responses of the pedestrian finite element model at different pitch angles for sedan and Sport

Hong, Cheng, Ye, Bin, Zhan, Zhenfei, Liu, Yu, Wan, Xinming, Hao, Haizhou

Research on Seakeeping Performance of Amphibious Rescue Vehicle Based on CFD

2025-01-8795

04/01/2025

Amphibious vehicles are widely used in civil and military scenarios due to their excellent driving performance in water and on land, unique application scenarios and rapid response capabilities. In the field of civil rescue, the hydrodynamic performance of amphibious vehicles directly affects the speed and accuracy of rescue, and is also related to the life safety of rescuers. In the existing research on the hydrodynamic performance of amphibious vehicles, seakeeping performance has always been the focus of research by researchers and amphibious vehicle manufacturers, but most of the existing research focuses on the navigation performance of amphibious vehicles in still water. In actual application scenarios, amphibious vehicles often face complex water conditions when performing emergency rescue tasks, so it is very important to study the navigation performance of amphibious vehicles in waves. Aiming at the goal of studying the navigation performance of amphibious vehicles in waves

Zhang, Yu

CFD Analysis on the Effect of Circular Cavity at Different Location of Airfoil Surface

2025-28-0074

02/07/2025

The paper present numerical effects of supercritical airfoil SC (2) 0414 having circular cavities at three different chord wise locations from leading to trailing edge. Here passive control method is widely applied by altering the \baseline airfoil surface coordinates to ascertain the aerodynamic behavior of the cavity at 40 %, 50 % and 60 % of the chord length respectively. The cavity shapes were deformed using Bezier curve to observe vortex pattern in the cavity region. Structured meshing was employed. The analysis was performed on SC 2 (0) 414 two-dimensional airfoil using commercial CFD ANSYS Fluent software where Spalart- Allmaras turbulence model technique is chosen to solve boundary layer problems on adverse pressure gradient and tested at extended range of angle of attack (-150 to 150) at Mach number 0.85. The study highlights the aerodynamic characteristics of lifting coefficient, drag coefficient and lift to drag ratio. It was observed that the cavity in suction surface

Pushparaj, Catherine Victoria, P, Booma Devi, D, Piriadarshani, Ganesan, Balaji, Ganesan, Santhosh Kumar, Raja, Vijayanandh

Modeling and Analysis of Comfort Braking Control Based on Brake-by-Wire and Active Suspension Systems

10-09-02-0011

02/07/2025

As wire control systems advance, they have given rise to a diverse suite of advanced driver assistance services and sophisticated fusion control capabilities. This article presents an innovative strategy for achieving comfortable braking in electric vehicles, propelled by the unwavering goal of enhancing driving experience. By integrating active suspension systems with brake-by-wire technology, the approach ensures that drivers retain their confidence throughout the braking process. The brake-by-wire system adeptly discerns the driver’s braking intent through the pedal’s displacement sensor. Utilizing this technology, we have developed a pioneering function aimed at delivering comfort braking control (CBC). This function not only refines the braking experience but also solidifies the driver’s trust in the braking system. Designed to counteract the head nodding effect during vehicle deceleration, the CBC system minimizes or even eradicates the jarring sensation of pitching for both the

Tian, Boshi, Li, Liang, Liao, Yinsheng, Lv, Haijun, Qu, Wenying, Hu, Zhiming, Sun, Yue

Vibration Suppression of a Flexible Appendage and Pitch Angle Fuzzy Regulation of a Spacecraft

01-18-01-0004

02/05/2025

In this work, the large-angle rotational movement and vibration suppression of a flexible spacecraft are carried out based on an adjustable system. First the spacecraft model is transformed into a canonical affine control form, then two fuzzy systems are used: The first (of Takagi–Sugeno type) estimates the feedback linearization control law as a whole, while the second (of Mamdani type) adjusts and stabilizes the control parameters using the gradient descent technique and based on the minimization of the control error rather than the tracking error. Stability results are presented in terms of Lyapunov’s theory, and simulation tests illustrate the significant transient robustness of the closed-loop system against perturbations, the accurate trajectory control, and vibration suppression of the flexible spacecraft. Consequently, as will be shown later, the error will stay confined and converges quickly to zero, confirming the smoothing property of the proposed method using fuzzy logic

Bahita, Mohamed

Ground Height and Pitch Angle Influence on the Aerodynamic Behavior of a Production Pickup Truck

2024-36-0011

12/20/2024

The fuel economy performance of road vehicles is one of the most important factors for a successful project in the current automotive industry due to greenhouse effect gases reduction goals. Aerodynamics and vehicle dynamics play key roles on leading the automaker fulfill those factors. The drag coefficient and frontal area of the vehicle are affected by several conditions, where the ground height and pitch angle are very relevant, especially for pickup trucks. In this work, we present a combined study of suspension trim heights and aerodynamics performance of a production pickup truck, where three different loading conditions are considered. The three weight configurations are evaluated both in terms of ground height and pitch angle change considering the suspension and tires deflection and these changes are evaluated in terms of drag coefficient performance, using a Lattice-Boltzmann transient solver. Results are compared with the baseline vehicle at road speed condition, where both

Buscariolo, Filipe Fabian, Terra, Rafael Tedim

Enhancing Roll Reduction in Road Vehicles on Uneven Surfaces through the Fusion of Proportional Control and Reinforcement Learning

10-09-01-0006

12/09/2024

This research addresses the pivotal role of active anti-roll bars in mitigating vehicle body roll during cornering, thereby enhancing overall stability, maneuverability, and comfort. The proposed approach integrates two distinct control methodologies—a straightforward error proportional controller and a reinforcement learning (RL)-based controller. Each front and rear active anti-roll bar applies a roll-reducing torque computed by the proportional controller during cornering. However, this torque alone proves insufficient in effectively damping roll oscillations induced by road irregularities. The RL-based controller leverages observations encompassing inertial measurement unit data (roll rate, pitch rate, and vertical acceleration), and wheel vertical displacements and employs the roll as a reward signal. This controller calculates two additional corrective torques. These torques are seamlessly incorporated by both front and rear anti-roll bars alongside the proportional controller

Marotta, Raffaele, Strano, Salvatore, Terzo, Mario, Tordela , Ciro

Active Hydro-Pneumatic Suspension Active Disturbance Rejection Sliding Mode Control for Improved Vehicle Stability

2024-28-0215

12/05/2024

Hydro-pneumatic suspension is widely used because of its desirable nonlinear stiffness and damping characteristics. However, the presence of parameter uncertainties and high nonlinearities in the system, lead to unsatisfactory control performance of the traditional controller in practical applications. In response to this challenge, this paper proposes a novel stability control method for active hydro-pneumatic suspension (AHPS). Firstly, a nonlinear mathematical model of the hydro-pneumatic suspension, considering the seal friction, is established based on the hydraulic principle and the knowledge of Fluid dynamics. On the basis of the established hydro-pneumatic suspension nonlinear model, a vehicle dynamics model is established. Secondly, an active disturbance rejection sliding mode controller (ADRSMC) is designed for the vertical, roll, and pitch motions of the sprung mass. The lumped disturbance caused by the model nonlinearities and uncertainties is estimated by the extended

Niu, Changsheng, Liu, Xiaoang, Jia, Xing, Gong, Bo, Xu, Bo

Ride Comfort Efficiency of Passenger Car’s Seat Using the Structure of Negative Stiffness with Various Dynamic Models

15-18-01-0003

10/03/2024

Three dynamic models of a passenger car including the one-dimensional dynamic model, two-dimensional dynamic model, and three-dimensional dynamic model are built to evaluate the ride quality of the passenger car as well as the isolating performance of the SNS (structure of negative stiffness). The decrease of the root-mean-square (RMS) accelerations in the seat and car’s body shaking is the research goal. The investigation results indicate that under all working conditions including the various excitations of the road surface and various velocities of the passenger car, the seat’s acceleration with SNS is strongly ameliorated in comparison without SNS in all three models of the passenger car. Particularly, the RMS seat acceleration with SNS in one-, two-, and three-dimensional models is strongly reduced in comparison without SNS by 76.87%, 66.15%, and 70.59%, respectively. Thus, the seat’s SNS has a good effect in isolating the vertical vibration of the passenger car’s seat. However

Zhang, Lei, Li, Tao, Yang, Guixing

Analysis of the Mechanisms by which Spline Pitch Errors Affect Powertrain Vibration

2024-01-2910

06/12/2024

As environmental concerns have taken the spotlight, electrified powertrains are rapidly being integrated into vehicles across various brands, boosting their market share. With the increasing adoption of electric vehicles, market demands are growing, and competition is intensifying. This trend has led to stricter standards for noise and vibration as well. To meet these requirements, it is necessary to not only address the inherent noise and vibration sources in electric powertrains, primarily from motors and gearboxes, but also to analyze the impact of the spline power transmission structure on system vibration and noise. Especially crucial is the consideration of manufacturing discrepancies, such as pitch errors in splines, which various studies have highlighted as contributors to noise and vibration in electric powertrains. This paper focuses on comparing and analyzing the influence of spline pitch errors on two layout configurations of motor and gearbox spline coupling structures

Park, Sohee, Min, Gyeonghwi

Design and Manufacturing of an Inclinometer Sensing Element for Launch Vehicle Applications

2024-26-0419

06/01/2024

Indian Space Research Organisation (ISRO) uses indigenously developed launch vehicles like PSLV, GSLV, LVM3 and SSLV for placing remote sensing and communication satellites along with spacecrafts for other important scientific applications into earth bound orbits. Navigation systems present in the launch vehicle play a pivotal role in achieving the intended orbits for these spacecrafts. During the assembly of these navigation packages on the launch vehicle, it is required to measure the initial tilt of the navigation sensors for any misalignment corrections, which is given as input to the navigation software. A high precision inclinometer is required to measure these tilts with a resolution of 1 arc-second. In this regard, an indigenous inclinometer is being designed. The sensing element of this design comprises of a compliant mechanism which is designed to sense the tilt by measuring the displacement of a proof mass occurring due to the respective component of earth’s gravitational

Shaju, Tony M, Krishna, Nirmal, Rao, G Nagamalleswara, Kumar, T Suresh, K, Pradeep

Structural Loads for Crew Escape System of Human Space Flight during Abort

2024-26-0453

06/01/2024

In any human space flight program, safety of the crew is of utmost priority. In case of exigency in atmospheric flight, the crew is safely and quickly rescued from the launch vehicle using Crew Escape System (CES). CES is a critical part of the Human Space Flight which carries the crew module away from the ascending launch vehicle by firing its rocket motors (Pitch Motor (PM), Low altitude Escape Motor (LEM) and High altitude Escape Motor (HEM)). The structural loads experienced by the CES during the mission abort are severe as the propulsive, aerodynamic and inertial forces on the vehicle are significantly high. Since the mission abort can occur at anytime during the ascent phase of the launch vehicle, trajectory profiles are generated for abort at every one second interval of ascent flight period considering several combinations of dispersions on various propulsive parameters of abort motors and aero parameters. Depending on the time of abort, the ignition delay of PM, LEM and HEM

S, Subash, Babu P, Girish, Daniel, Sajan

Mathematical Model for the Rotation of a Door Including Vehicle Inclination

2024-01-5045

04/17/2024

The analysis presented in this document demonstrates the mathematical model approach for determining the rotation of a door about the hinge axis. Additional results from the model are the torque due to gravity about the axis, opening force, and the door hold open check link force. Vector mechanics, equations of a plane, and parametric equations were utilized to develop this model, which only requires coordinate points as inputs. This model allows for various hinge axis angles and door rotation angles to quickly be analyzed. Vehicle pitch and roll angles may also be input along with door mass to determine the torque about the hinge axis. The vector calculations to determine the moment arm of the door check link and its resulting force are demonstrated for both a standard check link design and an alternate check link design that has the link connected to a slider translated along a shaft. This math model may be implemented using commonly available programs such as Microsoft Excel VBA or

Storck, Phillip

Design, Modeling, and Analysis of Heave and Roll Decoupled Suspension Geometry for a Formula Student Prototype

2024-01-2077

04/09/2024

This work aims to present the application of mode coupling to a Formula Student racing vehicle and propose a solution. The major modes of a vehicle are heave, pitch, roll, and warp. All these modes are highly coupled – which means changing suspension rates or geometry will affect all of them – while alleviating some and making others worse characteristics. Decoupling these modes, or at least some of them, would provide more control over suspension setup and more refined race car dynamics for a given layout of the racetrack. This could improve mechanical grip and yield significant performance improvements in closed-circuit racing. If exploited well, this approach could also assist in the operation of the vehicle at an optimal kinematic state of the suspension systems, to gain the best wheel orientations and maximize grip from the tires under the high lateral accelerations and varied excitations seen on a typical road course. Previous strategies used by other researchers to achieve

Panchal, Tanmay, Bastiaan, Jennifer

Development and optimization of jet impingement on dimpled plate for maximizing cooling performance of an inverter

2024-01-2216

04/09/2024

A need to develop a cooling method with high cooling performance like jet impingement is increased as high power of an inverter is required. Jet Impingement on the dimpled plate would increase thermal performance than that of flat plate. Many previous researchers have dealt with the multi jet impingement on flat plate and some results of the study on dimpled plate evaluate the effect on heat transfer coefficients on several limited cases, making it difficult to apply them to inverter designs. Therefore, in this paper, heat transfer performance, pressure drop, and robustness at micro-scale of jet impingement on the dimpled plate were investigated in detail and the correlations of each performance were proposed. Finally, the optimal design was presented. The cooling performance was influenced by the jet array and the effect of depth and width of the dimples. The former can be expressed in terms of the Reynolds number, the ratio of height to nozzle diameter(H/D), the ratio of pitch to

LEE, Hyeseung, Yang, Ilsuk, Jeong, Hojin, Park, Minkyu

Determination of Helical Spring Coefficient of Electric Motor Micro-Truck Vehicle with Independent Suspension on Front Axle

2024-01-5020

02/12/2024

Load-carrying transportation has recently increased due to cargo and online home shopping. As a result, there is a growing demand for vehicles that can pass through narrow streets and carry loads for short distances. Electric vehicles are vital in the automotive industry due to their zero emissions and further promotion through new regulations. This study is focused on determining the spring coefficients of helical springs for a micro-truck vehicle, which will be used for cargo transportation and has a leaf spring with a specific spring coefficient on the rear axle and an independent double wishbone suspension system on the front axle. In addition to being vehicles with low weight values, micro-trucks have the axle capacity required for urban transportation due to their low track width and dimensions. Correctly determining the leaf spring is essential as it will directly affect the loads on the suspension system, wheel life, energy consumption, and comfort level. When determining the

Canpolat, Berkan, Akbaba, Mahir, Çifci, Erol, Doğan, Mehmet Ali

High Speed Driveline Power Loss and Influencing Factors

2024-26-0337

01/16/2024

Energy savings in automotive applications has always remain an important aspect of research. In addition, today’s highspeed requirements in electric vehicles require high-efficiency drivelines to match overall vehicle mileage or range. This paper presents the validation of the overall efficiency & drag losses of the highspeed Driveline for an ATV with 4-Wheel Drive System. The efficiency & drag losses were measured in the powertrain testbed where the test units were placed between two Transient Dynamometers. The main aim of the test was to validate the overall efficiency as a function of input speed and torque. All these measured values of the gearbox efficiency are included in various graphs. The tests were performed for complete functional range of test unit at max operating oil temperatures for Transmission and Front Differential testing. Drive shafts tests were performed at its complete range and various inclination angle up to max failure point. The wheel hub was tested at various

Jain, Sankalp, Singh, Parminder

Adopting Pothole Mitigation System for Improved Ride, Handling and Enhanced Component Life

2024-26-0059

01/16/2024

Potholes are a major cause of discomfort for riders and vehicle damage. The passive suspension systems which are used in the passenger vehicles are primarily reaction based. These can’t adapt to the changing road conditions which means the best ride quality and handling characteristics cannot be ensured for different driving situations. Passive suspension system also needs more maintenance due to its inability to reduce the impact of the road irregularities. In recent years, semi-active suspension systems have been developed to improve ride comfort and vehicle safety. This paper covers the integration of a semi-active suspension system with a road preview mechanism with a TATA car model to investigate its impact on ride comfort, handling characteristics and component loads in digital domain. A quarter car vehicle model is used to compare different active damping control strategies. The best strategy is selected and integrated in a full vehicle MBS model to gain deeper insight on ride

Mishra, Satyakam, Prasad, Tej, Maruenda Sanz, Javier

Performance, Nut, Self-Locking, Castellated, Prevailing Torque, UNJ 16 Pitch Thread Form

AS4958B (Current)

01/16/2024

This document covers all metal, castellated, self-locking nuts made from alloy steel of the types identified under the Unified Numbering System as UNS G41300 and UNS G43400.

E-25 General Standards for Aerospace and Propulsion Systems

Hierarchical Control Strategy for Active Suspension Equipped with an Electromagnetic Actuator

2023-01-7077

12/31/2023

Electromagnetic suspension systems have increasingly gained widespread attention due to their superiority in improving ride comfort while providing fast response, excellent controllability and high mechanical efficiency, but their applications are limited due to the accuracy of the underlying control actuation tracking. For addressing this problem, this study presents a novel hierarchical control strategy for an electromagnetic active suspension (EMAS) system equipped with an electromagnetic actuator (EMA) structure. The structure of the EMA device and the working principle of the motion conversion model are introduced in detail first, and the motion conversion equation is derived based on the force-torque relationship. Based on this, a linear quadratic regulator (LQR) control method is proposed to be applied to a half-vehicle suspension system to improve the vibration isolation performance of the vehicle and ensure the ride comfort. Then, the underlying layer control of the permanent

Lai, Jiewen, Zhang, Bangji, Qin, An, Zeng, Sheng, Wang, Shichen

Real-Time Road Slope Estimation Based on GNSS/INS Fusion System Considering Slope Change

2023-01-7043

12/20/2023

For intelligent vehicles, a fast and accurate estimation of road slope is of great significance for many aspects, including the steering comfort, fuel economy, vehicle stability control, driving decision-making, etc. But the commonly used estimation methods nowadays usually demand additional sensors or complex dynamic models, causing increase in system complexity as well as decrease in accuracy. To solve these problems, this paper puts forward a real-time road slope estimation algorithm leveraging the relationship between pitch angle and road slope, which only requires low sensors cost and computational complexity. Firstly, a GNSS/INS fusion system is established to obtain the pitch angle with respect to the navigation frame, which couples the vehicle’s pitch angle in vehicle frame and road slope angle. Then, based on the different characteristics in frequency domain of the two components, frequency domain analysis is conducted and low-pass filter is used to separate out road slope

Chen, Mengyuan, Xiong, Lu, Gao, Letian

Improvement of Torque Density Using Output Reduction Method in Transmission

2023-28-0050

11/10/2023

Gears are one of the vital components to transmit torque efficiently. Helical gears are chosen as they transmit higher torque with lesser noise compared to spur gears of same size. All new age gearboxes require to transmit maximum torque with minimum packaging space available to improve torque density. Ways of reducing weight are using lesser density material, decreasing centre distance, and thereby reducing pitch circle diameter of all gears, etc. However, they will also affect torque carrying capacity of gearbox which can lead to gear failure in conventional transmission architecture gearboxes with input reduction method. In input reduction method, torque gets multiplied from input shaft to countershaft. Countershaft torque is multiplied to output shaft gears requiring higher torque capacity gears on output shaft. In this research, output shaft reduction architecture is proposed to avoid torque multiplication from input shaft to countershaft gears. It helps to reduce gear sizing on

R, Manikandan, K, Barathi Raja, Kumar, Aneesh, Ostwal, Amit

Flow-Through Transducer for Wind Tunnel Analysis

TBMG-48250

06/01/2023

Existing integral flow-through balances have been limited to five-component force and moment measurements (normal and side force; pitch, yaw, and rolling moment) excluding a sixth desired force measurement: axial force. To enable key aerospace R&D applications, NASA’s Langley Research Center has developed a single-piece flow-through transducer design capable of measuring all six components adding in the Axial force measurement.

Reaction Rod Link in Rear Cab Suspension to Control Cab Dynamics in Tractor-Semitrailer Vehicles

02-16-04-0024

05/24/2023

Articulated vehicles form an important part of our society for the transport of goods. Compared to rigid trucks, tractor-trailer combinations can transport huge quantities of load without increasing the axle load. The fifth wheel (FW) acts as a bridge between the tractor and trailer, which can be moved within the range to achieve rated front and rear axle loads. When the FW is moved front, it adversely affects the cab dynamics and cab suspension forces. Compared to the cab pitch and roll, yaw motion increases drastically. The current study tries to address this issue by providing reaction rod links in the rear cab suspension. In this study, a 4×2 tractor with a three-axle semitrailer is considered by keeping the FW at its frontmost position, which is the worst-case scenario for a cab. Three different cases of reaction rod arrangement and its influence on cab dynamics are studied in comparison with a model without reaction rods. To assess this, time signal–based relative pseudo-fatigue

Bhat, Sindhoor

Test Results of Tires for All-Terrain Vehicles from a Flat-Trac® Machine

2023-01-0671

04/11/2023

This paper presents tire data from an All-Terrain Vehicle (ATV). Data is collected on a Flat-Trac® machine where force and moment data were collected for three tires: one front tire and two rear tires. Tests were conducted at slip angles of +/-28 degrees, varying normal loads and inclinations angles. Additionally, tests were conducted at varying levels of inflation pressure. Key parametric data such as aligning moment, cornering and vertical stiffness levels are presented. One key finding from this study is that, in general, as inflation pressure increases cornering and aligning moment stiffness decreases. This effect is counter to typical passenger vehicle tires, where higher inflation pressure usually results in higher stiffness levels. Using results from the tire test data, understeer calculations are made for a vehicle under varying loading conditions.

Zagorski, Scott, Heydinger, Gary

Thermal Management Design and Simulation of Symmetric Air-Cooled System for Lithium Battery

2023-01-0517

04/11/2023

Good heat dissipation of Lithium battery can prevent the battery from shortening its life due to rapid aging or thermal runaway. In this paper, an air-cooled structure of 5 series and 3 parallel battery packs is designed, which combines the advantages of series and parallel air ducts and optimizes the heat dissipation effect and the space ratio of air ducts. First, the heat generation model of NCR18650PF lithium battery is established, and the heat generation rate and time under different discharge rates are calculated. Combined with the working conditions of the battery itself, the necessity of battery pack heat dissipation was found. Secondly, a preliminary three-dimensional model of the battery pack heat dissipation was established, and a simulation analysis was carried out to study the influence of the inclination angle of the inlet duct, the arrangement of the air inlet and outlet, and the influence of the deflector on the heat dissipation effect, and the optimization analysis was

Ding, Kangjie, Lin, Zhenmao, Xie, Beichen

Side Door Hinge Axis Deviation and Skewness Study on the Door Closing Effort

2023-01-0610

04/11/2023

The side door closing effort is one of the main evaluating parameters which demonstrates the build quality of the vehicle. The side door hinge axis inclination is one of the key attributes that affect the side door closing effort. Commonly, the hinge axis is inclined in two directions of a vehicle to have necessary door rise during the door opening event. Due to the process and assembly variations in the door assembly, the upper and lower hinge axis of the side door deviates from the design axis. In this paper, the deviations in the side door hinge axis and its effects on the side door closing velocity is discussed. The deviations of the side door hinge axis are studied with a coordinate measuring machine. The side door closing velocity of the vehicle is measured with the velocity meter. The study revealed that side door closing velocity is increasing with an increase in the deviation of the top and bottom door hinge axis from the design hinge axis. The hinge axis skewness between the

Selvan, Veera, Askari, Hasan, Bhosale, Mukund, Unadkat, Siddharth, Pandurangan, Venugopal

Deep Reinforcement Learning Achieves Multifunctional Morphing Airfoil Control

23AERP02_07

02/01/2023

Smooth camber morphing aircraft offer increased control authority and improved aerodynamic efficiency. Smart material actuators have become a popular driving force for shape changes, capable of adhering to weight and size constraints and allowing for simplicity in mechanical design. University of Michigan, Ann Arbor, MI Uncrewed aerial vehicles (UAVs) are growing in popularity for both civilian and military applications, which makes improving their efficiency and adaptability for various aerial environments an attractive objective. Many studies pursue this goal using morphing techniques that incorporate shape changes not typically seen in traditional aircraft. Due to weight and volume constraints consistent with smaller flight vehicles, smart materials, such as macro fiber composites (MFCs), have been used to achieve the desired shape changes. Macro fiber composites are low-profile piezoelectric actuators which have gained substantial attention within the morphing aircraft community

Influence of Rail Grinding Operations on the World's Largest Multimodal Network

2022-28-0560

12/23/2022

Rail-wheel interaction plays a key role in determining the life of railway tracks. An increase in the speed and axle load leads to significant wear and fatigue damage on materials resulting in a safety concern for the Indian Railway network. In response to the above context, rail grinding technology is introduced to maintain the stability and safety of the railway system. In the present work, three (3) Zones named South-Central Railway (SCR), North Central Railway (NCR) and Northern Railway (NR) of Indian Railways (IR) were prone to severe problems pertaining to wear and fatigue damage were selected for the rail grinding performance studies. From the collected data, the performance features in terms of rail wear, width and position of contact band, length and pitch of crack, attainment of target profile, defect generation rate and rail/weld fracture analysis were evaluated. Average wear rates per 100 Gross Million Tonnes (GMT) at SCR, NCR and NR for the tangent track were found to be

Verma, Sachin, Joseph Selvi, Binoj, Yogesh Shah, Vijesh

Influence Analysis of the Gear Manufacturing Error on Transmission Vibration Response

15-16-02-0006

12/05/2022

Gear transmission error (TE) is one of the internal excitation on transmission system vibration and noise. The vibration analytical model of transmission system was constructed by considering the dynamical characteristics of a gear box, which were verified by comparing the modal frequency and mode shapes between simulation results and experiment data. The vibration and radiated noise of transmission was analyzed by the transmission NVH test data. The mechanism of load conditions, TE, and system resonance influence on transmission system vibration and noise are investigated in details. Based on the vibration analysis model, the effects of pitch error, helix tilt deviation, and radial runout error on gear pair meshing characteristics and system vibration response are studied individual. The analysis results show that with the increase of pitch deviation and radial runout error, the harmonic transmission error of gears increase in varying degrees; the large helix tilt deviation not only

Tao, Wei, Xiaochun, Zeng, Zhisheng, Zhao, Yi, Wang, Zheng, Guangze, Huang, Huang Xiupeng

Computational Analysis of Pitch Sensitivity for a Concept Race Car

2022-01-5065

10/06/2022

The present numerical study investigates the design and analysis of a concept model Le Mans Grand Touring Prototype (LMGTP) car. Through analysis, aerodynamic pitch sensitivity and related factors are found to be detrimental to the straight-line stability of these high-speed race cars. Simulations are carried out on a commercial Computational Fluid Dynamics (CFD) tool for varying pitch angles of the car from −1° to +2.5°. For each pitch angle, steady-state pressure contours, velocity contours, and streamlines are presented. Additionally, coefficients and force values of lift and drag are calculated with the k-omega turbulence model implemented. Obtained numerical results are validated via Ahmed Body studies reported in the literature, and an average error deviation of 1.013% is exhibited. It is observed that lift force at the front axle increases with increasing pitch angles, leading to reduced pitch stability. At a peak of 2.5° pitch angle, the destabilizing lift force peaks at 1872 N

Anbalagan, Satheesh, Deepak, Chirag, Virmani, Kartik, Madhogaria, Tanishq, Ramesh, Rathan, Narendhra, Tharun M.V., Panneerselvam, Padmanathan

Advance Cabin Simulation in 1D CAE to Predict Occupants Nose Level Air Temperature

2022-28-0387

10/05/2022

Mobile Air Conditioning (MAC) system provides year round thermal comfort to the occupants inside vehicle cabin. In present scenario, 1D CAE simulation tools are widely used for MAC system design, component sizing, component selection and cool down performance prediction. The MAC component sizing and selection mainly depends on cooling load which varies with ambient conditions, occupancy, cabin size, geometry and material properties. Therefore, detailed modeling of vehicle cabin is essential during MAC system digital validation as it helps to predict performance across wide number of contributing factors. There are two different methods available in 1D Simulation for vehicle cabin modeling, viz. ‘simple cabin’ and ‘advance cabin’. With the simple cabin modeling approach, vehicle cabin is modelled as a group of lumped masses, which only enables prediction of average vent and average cabin temperatures. In advance cabin modeling approach, vehicle cabin is modelled more comprehensively

Jaybhay, Sambhaji, Kapoor, Sangeet, Varma, Mohit, Venu, Santosh, Kulkarni, Shridhar

Braking Dynamics of Auto-Rickshaw

2022-28-0382

10/05/2022

Auto-rickshaw is one of the most customary modes of transport in urban as well as rural areas of India. The safety of this vehicle is of prime concern. The braking system plays a vital role in the safety of any vehicle. This work is carried out in order to analyze the vehicle behavior during braking maneuver since the literature survey carried out had fewer details about the braking performance of Auto-rickshaw. Bajaj RE was chosen in particular for our study because it is widely used. Stopping distance analysis is utilized in order to estimate the vehicle braking performance. The straight-line braking performance is studied with the help of a 3-DOF mathematical model of the vehicle developed which includes the surge, heave and pitch motions. This model is formulated based on the Newtonian approach and is built on Simulink environment. The complete brake system is developed and coupled with the mathematical model. The Pacejka tire model is implemented in order to obtain accurate

M H, Akshith, Anand, Srijan, Chakravarthy, Raghav, N H, Hemanth, Patil, Sharanbasappa

Model Following Damping Force Control for Vehicle Body Motion during Transient Cornering

10-06-04-0023

08/16/2022

The aim of this study is to achieve the target transient posture of a vehicle according to the user’s steering operation. The target behavior was hypothesized to be a roll mode in the diving pitch, even during steering inputs on rough surfaces, in order to improve subjective evaluation. As a result of organizing the issues of feedforward control (FF) and feedback control (FB), we hypothesized that it would be appropriate to follow the ideal posture. The model following damping control (MFDC) was newly proposed by the authors as a solution to a control algorithm based on model-following control. The feature employs skyhook control (SH), which follows the deviation between the behavior of the reference model, which generates a target behavior with no input from the road surface, and the actual behavior of the vehicle. Numerical analyses were performed to verify the followability of the target behavior and the effect of roll damping performance. As a result of conducting actual vehicle

Kikuchi, Hironobu, Inaba, Kazuaki

An Alternative Solution to Vehicles Audio System using Inertial Transducers Integrated in Trim Parts: Advanced Developments.

2022-01-097006/15/2022

The use of inertial transducers to replace traditional loudspeakers is an innovative way to reproduce a quality audio signal in a vehicle cockpit while significantly reducing on-board mass and overall volume of the audio system. An electrodynamic inertial exciter is an actuator commonly used for the realization of distributed mode loudspeakers or DML (Distributed Mode Loudspeaker) to generate vibrations of a panel radiating an acoustic wave. As for a loudspeaker, an inertial exciter implements a coupling process and is based on the interactions between a current and a magnetic field. The coil is movable and the magnetic mass stationary in the case of the loudspeaker, while the reverse is true for the inertial exciter. This paper presents the development process of a new inertial transducer and its optimization by digital simulation, validated by tests on physical prototypes. The innovation uses a new patented mechanism for suspending and guiding the moving magnetic mass to reduce

Thome, Jean-Philippe, Duval, Arnaud, Defosse, Herve

Opening Distortion Fingerprint (ODF) - A New Body Evaluation Method for Perceived Quality and Vehicle Dynamics

2022-01-095006/15/2022

The body performance of an electrical vehicle is significantly affected by the structural integration of the stiff battery package. In addition, the body topology of future electrical vehicles/mobility solutions will differ clearly from conventional ones, e.g. no B-pillar. This makes the current body requirement such as static torsional stiffness less relevant. In order to meet the new challenges during the virtual development phase a new body evaluation method has been developed. The method uses the dynamic distortion in all openings in a complete vehicle setup to calculate the so-called Opening Distortion Fingerprint (ODF). The ODF evaluation is performed in time and frequency domain. The application of this new method is shown in both test and simulation. There are two main areas of application. One of them is Perceived Quality where the ODF can be used as a new body assessment criterion. This also includes the calculation of an equivalent static load (ESL) based on the ODF, which

Weber, Jens, Jönsson, Viktor, Hansson, Lars, Varela, Roberta, Käck, Britta

In-Flight Thrust Determination for Aircraft with Thrust Vectoring

AIR6007 (Current)

06/14/2022

The purpose of this document is to provide guidance on in-flight thrust determination of engines that are impacted by intentional or unintentional thrust vectoring. However, as indicated in the Foreword, the field of aircraft thrust vectoring is varied and complex. For simplicity and coherence of purpose, this document will be limited in scope to multi-axis thrust vectoring nozzles or vanes attached to the rear of the engine or airfame; single-axis thrust vectoring and unintentional thrust vectoring (fixed shelf or deck configuration) are special cases of this discussion. Specifically excluded from this scope are thrust vectoring created primarily by airframe components such as wing flaps, etc.; lift engines, propulsive fans and thrust augmenting ejectors; and powerplants that rotate or otherwise move with respect to the airframe. Note that thrust reversing, which is also a special case of thrust vectoring (vector angles greater than 90 degrees), is covered by a separate SAE Aerospace

E-33 In Flight Propulsion Measurement Committee

Effect of Varying Diffuser Vane Height on NASA CC3 4:1 Centrifugal Stage Performance

2022-26-0019

05/26/2022

This work is aimed at conducting a computational study to find out the effect of vaneless space downstream of the Diffuser vane trailing edge, by varying the height of diffuser vane viz. 50%, 75%, and 100% diffuser height, on centrifugal stage performance. The considered centrifugal compressor stage in this study is NASA CC3 4:1 centrifugal stage. In all the cases diffuser leading-edge radius is the same. The compressor performance with full diffuser vane configuration (100% diffuser height) is computed and initially compared with test data. The diffuser vane height is then reduced to 50% and 75% of the original length from the diffuser leading edge. Hence, the diffuser leading-edge location remains the same as the original 100% diffuser vane height geometry whereas the location of the trailing edge changes according to vane height. Another part of the study is to model the 75% & 100% diffuser vane height with hub and shroud gaps respectively. The computational study is carried out

Kumar, Shailesh, Chougule, Hasham, Abdullah, Qizar, Goswami, Shraman

V-Ribbed Belts and Pulleys

J1459_202205 (Current)

05/16/2022

This SAE Standard covers the dimensioning technique, tolerances, and methods of measurement of V-ribbed belts and mating pulleys for use on automotive accessory drives.

Belt Drive (Automotive) Systems Committee

Research on Gesture Recognition Algorithm Based on Millimeter-Wave Radar in Vehicle Scene

2022-01-7017

03/31/2022

With the increasing intelligence of human society, people's demand for human-computer interaction is also increasing. As an important communication medium for human to express information, gesture has always been an important topic in human-computer interaction. Using gesture recognition technology in the vehicle environment can reduce the operation difficulty during driving, reduce the possibility of driver distraction, and greatly improve driving safety and driving experience. Millimeter wave radar can effectively protect the privacy in the car from being leaked, and can still work normally in the dark interior environment. Moreover, with the development of millimeter wave technology from 24g to 60g and 77g, the improvement of its resolution further improves its ability to detect small displacement. Therefore, the gesture recognition technology using millimeter wave radar has been developed. In this paper, 3DCNN and series LSTM network structures are designed, and 3DCNN network

Wang, Xiuqing, Bai, Jie, Zhu, XiChan, Huang, LiBo, Xiong, Min

Research on Brake Comfort Based on Brake-by-Wire System Control

2022-01-0912

03/29/2022

The vehicle will produce certain shock and vibration during the braking process, which will affect the driving experience of the driver. Aiming at the problems of pitch vibration, longitudinal vibration and shock during the braking process, this paper proposes a planning and following control method for target longitudinal acceleration in post-braking phase, and designs control trigger strategies. Target longitudinal acceleration planning takes minimizing longitudinal shock as the design goal. The following control takes the brake pressure as the control object, and adopts the “feedforward +PID feedback” method to follow the target longitudinal acceleration. Besides, considering the safety of braking process, the trigger condition of control is designed which utilizes BP neural network method to judge whether the control has to be triggered. Based on Simulink software, the simulation model of straight-line braking is established. The results of straight-line braking simulation show

Xiong, Wei, Wang, Weiwei, Jiang, Kaihong, Hou, Liming, Shangguan, Wen-Bin

Vehicle Dynamics Analysis and Optimization of Electric All-Terrain Vehicle

2022-01-0913

03/29/2022

A Vehicle Dynamics Analysis of an electric All-Terrain Vehicle (ATV) is conducted and presented in the following paper. Vehicle performance is analyzed, shortcomings are identified and solutions to optimize the vehicle design are implemented. These optimizations are tested and results are compared with the pre-existing models and validated by conducting physical trials on the actual model. The virtual tests are carried out using Multi-Body Dynamics (MBD) tool- MSC ADAMS. The results obtained from the tests have been put forth in theoretical as well as graphical manner to get a clearer view. This research involved a thorough study of Lateral and Longitudinal Dynamics of the ATV. Trends in dynamic parameters like the ride quality, pitch response, roll stability, yaw response, camber gain and other important parameters of the vehicle have been studied and its correlation with the feedback obtained from the driver is established. Key features of the vehicle that influence these parameters

Shetty, Kartik, Mache, Ashok, Joshi, Akshay, Kulkarni, Manas, Chitnis, Shreeya, Kulkarni, Shirish

Design of Smart Dual-Stage Battery Isolator for Commercial Vehicles

2022-01-0709

03/29/2022

With the enforcement of ever stringent emission norms, vehicular subsystems are witnessing a substantial transition from electro-mechanical to electronic control-based systems. With the inclusion of incremental modifications to be suitable for future applications, the electrical system has reached a point where it is undergoing a major transition. Further catalyzing this reform is the demand for mass passenger safety, bringing about its own set of uncompromising norms. While the implications of the regulations enforce cleaner and safer mobility, there also arises a conflict between vehicular functionality and safety. This paper enumerates on the first-hand experience of how the direct transfer of the elementary vehicle battery isolator from the prior euro-4 electrical system to the present euro-6 system resulted in a disharmonized vehicle operation when made to comply with both functionality and passenger safety norms. While safety norms mandate the operation of the battery isolator

Saha, Satya, Gaurav, Kumar, Patidar, Rahul, Patra, Arka

TRACKED VEHICLE PERFORMANCE ON IRREGULAR GROUND WITH PNEUMATIC SUSPENSIONS

2021-36-0089

02/04/2022

In a military vehicle, the decrease in pitch and bounce movements is important to achieve precision in the vehicle's weapon set. The suspension of the vehicle is responsible for filtering the terrain profile, increase the comfort of the occupants, and reduce the impacts on the vehicle components. This paper will continue the work published on "PERFORMANCE OF A VEHICLE ON CRAWLES ON IRREGULAR LAND WITH SUSPENSIONS EQUIPPED WITH MAGNETORREOLOGICAL SHOCK ABSORBERS" (2020-36-0145) analyzing the improvement in vehicle performance when implementing pneumatic springs in the suspension system. The vehicle selected is the APC M113 because it is a versatile vehicle, used by several countries, and for that reason, it is possible to obtain parameters more easily than other military vehicles. The vehicle will be analyzed in a MATLAB / Simulink environment, under two terrain configurations: a single speed bump and a series of 5-speed bumps.

de Miranda, Matheus, Teixeira da Costa Neto, Ricardo

Development of Resin Coated Piston suitable for Monolithic Cylinders made of Hypereutectic Al-Si Alloy

2022-32-0010

01/09/2022

This study focuses on improving durability of the resin coated piston developed especially for the monolithic cylinder made of a hypereutectic Al-Si alloy, so-called DiASil®. The newly developed resin was designed to be cured at a relatively low temperature considering over-aging of a piston and confirmed that it exhibited a lower friction coefficient compared to an existing resin coating. Furthermore, pistons of which skirts had various depth and pitch of grooves filled with the resin coating were offered to evaluate wear and seizure characteristics. The results showed deeper grooves on piston skirts were remarkably effective to delay a seizure. All the seizures were triggered when the ratio of Al substrate exposed to the sliding surface reached up to 60-80%, which implied it can be the empirical criteria for a seizure. Therefore, it can be considered the seizure does not occur as long as adequate resin coating remained in the grooves. Finally, influential factors for the seizure and

Watanabe, Keita, Kurita, Hirotaka

Estimation of Vehicle Attitude of Off-road Motorcycles Integrating Small and Lightweight On-board Equipment in Motocross and Cross-country

2022-32-0082

01/09/2022

Among others, off-road motorcycles are subject to changes in road surface conditions depending on weather conditions, and the influence of riding operation on their behavior is significant. Therefore, for consistent evaluation of handling stability, it is effective to quantitatively understand the amount of riding operation and vehicle behavior through data measurement. However, when riding off-road motorcycles, the impact on the vehicle is large, and there are problems with the impact resistance of the measurement equipment. There is also a high risk of damage to sensors due to entrapment of mud or stones, etc. Therefore, when using high-precision sensors, it is necessary to proceed with careful operational verification. In particular, since off-road motorcycles are designed to be lightweight, measurement equipment for them must be lightweight as well and compact enough to avoid possible large impact on the vehicle's dynamic characteristics. Due to such strict requirements for data

Uto, Yuki, Inoue, Shinichi, Yano, Kazuto

Influence of Fifth Wheel Position on Cab Durability and Dynamics in Tractor-Semitrailer Vehicle

02-15-02-0009

10/11/2021

Articulated vehicles contribute to the major portions of cargo transport through roads. Fifth wheel (FW) is an important component in these vehicles, which acts as the bridge between tractor and trailer and is often used as a parameter to adjust the axle loads. Ride and comfort studies linked to FW position exist. However, its influence on durability is often not considered seriously. In this article, three different FW positions placed at 200 mm, 400 mm, and 600 mm in front of the rear axle are studied virtually on a 4×2 tractor with three-axle semitrailer combination. To assess the risk associated with FW movement, acceleration-based pseudo-relative damage, power spectral density (PSD), and level crossing plots are analyzed for each FW position. Further, fatigue analysis is done on the cab structural components to understand the durability. Outcome shows that the FW position has an influence in determining the cab dynamics and durability of the components to a great extent. When the

Bhat, Sindhoor, Sheepri, Sunil

Experimental Study on SS 304 Sheet Metal for Bending Process Optimization using Response Surface Method

2021-28-0268

10/01/2021

Productivity plays a vital role in manufacturing processes as well as in service. Sheet metal bending process is a type of forming process that has been used by the wide range in industries. There are several tangible and intangible factors affecting the production rate during the bending process. Spring back is one of the severe factors which affects the production rate, especially in stainless steel material. The spring back is mostly affected by material properties, sheet thickness, bending radius, die sizes and component geometry. In this paper, the spring back is studied by the effect of various parameters such as rectangle/oblong slots with varying pitch distance and without slots and bending time in the stainless-steel material 304 grade in V-air bending machine. The experimental data are evaluated by means of the Response Surface Method (RSM). Finally, it was observed that explored results have the betterment of the production rate with connection to spring back. The study

NATARAJAN PhD, Balaji, SUBRAMANIAN, BALASUBRAMANI, KANAGARAJ, KANNAN, R, Soundararajan

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