Browse Topic: Center of gravity (CG)

Items (876)
Find
Reconstruction of Pedestrian-Vehicle Collisions Using 3D Skeletal Estimation from Vehicle-Mounted Camera Video2026-01-0575To be published on 04/07/2026
Since 2009, pedestrian fatalities caused by traffic accidents in the United States have increased by 78%, exceeding 7,000 deaths annually. To reduce injuries, a deeper understanding of injury mechanisms based on real-world accident data is required. Recently, accident reconstruction techniques utilizing recorded video from vehicle-mounted cameras have gained increasing attention in accident analysis. However, injuries resulting from contact with the road surface are often occluded due to camera blind spots, hindering accurate capture. Additionally, the low frame rate of many vehicle-mounted cameras limits the ability to accurately analyze the detailed kinematics of pedestrian impacts. To address these limitations, this study proposes a reconstruction method that estimates pedestrian motion in occluded regions by matching observed behavior from vehicle-mounted camera recorded video with simulation results. First, to reconstruct three-dimensional pedestrian motion from vehicle-mounted
Onishi, Koji, Wang, Kewang, Uno, Eriko, Ichikawa, Koji, Tanase, Noboru, Ando, Takahiro
Research on Attitude Control and Stability of Water-Wading Vehicles2026-01-0627To be published on 04/07/2026
With the intensification of global climate change, the frequency of extreme rainfall has increased, and the number of urban waterlogging and water-crossing sections in the wild has significantly risen. The scenarios where vehicles encounter complex water-crossing road conditions are also on the rise, which poses unprecedented challenges to the passability and safety of modern vehicles. This article conducts a study on the problem of attitude instability that occurs when vehicles are driving in water. Traditional vehicles have insufficient passability when wading through water. Their passive suspension systems cannot adaptively adjust when wading through water, resulting in insufficient vehicle stability and a high risk of serious accidents such as "water skidding" or even overturning. The safety of driving through water cannot be guaranteed. In this regard, this paper first establishes a dynamic model of a wading vehicle body considering the effect of buoyancy. On this basis, it
Li, LiuYuanHeng, Tan, Gangfeng, Dong, Chenchen, Fayzullayevich, Jamshid, Han, YiFei
A Study on Vehicle Cornering Stiffness Estimation Based on Recursive Least Squares Method2026-01-0630To be published on 04/07/2026
This paper investigates a vehicle cornering stiffness estimation method based on recursive least squares (RLS), aiming to enhance automotive active control capabilities. Conventional parameter identification schemes reliant on onboard sensors are constrained by sensing range and cost limitations. This study explores an estimation algorithm utilizing generic motion signals, derives the theoretical relationship between yaw rate response and yaw stiffness, and designs an RLS approach for online identification of relevant model parameters. In a simulation environment, applying an ideal steering angle excitation demonstrated that the RLS algorithm converges within approximately one second and successfully estimates the cornering stiffness with an error of less than 5% relative to the set true value. Results indicate that under known vehicle basic parameters and ideal input conditions, the proposed algorithm can effectively complete cornering stiffness estimation. This work establishes an
Lang, Tao, Tan, Gangfeng, duan, xianqi, Shen, Leiming, Liang, Shuang
Lateral stability and energy-saving integrated control of distributed drive vehicles with four wheel hub motors2026-01-0635To be published on 04/07/2026
Abstract: In order to improve the lateral stability and energy optimization of four-wheel hub motor distributed drive vehicles under complex road conditions, a layered control strategy for yaw stability is proposed. The upper controller is designed based on the sliding mode control principle to create a yaw moment controller, establishing both a two-degree-of-freedom model and a seven-degree-of-freedom model for the vehicle, tracking the desired yaw rate, desired center of mass side slip angle, actual yaw rate, and actual center of mass side slip angle to obtain the corresponding additional yaw moment. Moreover, the state of the vehicle is analyzed using the phase plane method of the center of mass side slip angle and yaw rate, and the total additional yaw moment for the vehicle is computed based on weighted calculations according to the state. Additionally, an unscented Kalman filter observer is established to enhance the tracking accuracy of the actual yaw rate and actual center of
shi, cheng'ao, liu, bingsen, Zou, Xiaojun, Wang, Tao, Zhang, Ming
Rapid Prediction Method for Crankshaft dynamic balancing Based on SolidWorks2026-01-0494To be published on 04/07/2026
As the core component of high-speed power systems such as internal combustion engines and compressors, the crankshaft’s dynamic balancing performance is a key factor influencing overall machine vibration, noise and operation reliability of the whole machine. In response to the problem whereby the traditional dynamic balancing correction method relies on empirical formulas and repeated trial weights, resulting in a long design cycle, this paper proposes a rapid prediction and optimized design method for the dynamic balancing performance of crankshafts based on SolidWorks. The method first determines the center of mass and the moment of inertia of the crankshaft through mass properties analysis, and then uses the motion simulation module for dynamic simulation to accurately predict the imbalance force and moment. In order to overcome the common numerical convergence difficulties and oscillations in the result curves in simulation, this study introduces a series of optimization strategies
Yang, Minghao, Zheng, Yuqing, Ma, Honghui, Chen, Hao
Rigid Two- and Three-Wheeled Vehicle Roll Over vs. Pitch Over Threshold Models: Testing and Analytical Modifications2026-01-0538To be published on 04/07/2026
The phenomenon of bicycle pitch over is simple in concept, yet determining threshold criteria for pitch over has yet to be well established, particularly when it comes to determining whether or not a bicycle’s front wheel will roll over a particular obstacle or not. Two prior SAE papers have laid out 3 different approaches to determining this threshold criteria; however, all three remain untested and thus unvalidated. To test the two analytical models, the dimensions and center of gravity location for a test rider on a tricycle were measured, and the test subject system was ridden over a series of progressively taller square edge obstacles until the tricycle transitioned from rolling over to stopping/pitching over. The test speeds were varied between 5 and 10 mph to keep the tricycle from fully pitching over and/or damaging the test tricycle. From this testing, it was demonstrated that the test tricycle and rider was able to ride over taller obstacles than calculated by the analytical
Sweet, David Michael, O'Brien, Nathan, Bretting, Gerald
Aircraft Tow BarARP1915E (Current)2/12/2026
This SAE Aerospace Recommended Practice (ARP) specifies dimensional and physical requirements of tow bar connections to tractor and aircraft (see Figure 1). It is applicable to all types of commercial transport category aircraft tow bar. The purpose of this SAE Aerospace Recommended Practice (ARP) is to standardize tow bar attachments to airplane and tractor according to the mass category of the towed aircraft, so that one tow bar head with different shear levels can be used for all aircraft that are within the same mass category and are manufactured in compliance with AS1614 or ISO 8267.
AGE-3 Aircraft Ground Support Equipment Committee
Evaluation of Methods Used to Determine Vehicle Center of Gravity Height2026-26-05131/16/2026
This paper contains theoretical and experimental studies of the measurement accuracies of two methods commonly used by vehicle industries and other stakeholders to determine vehicle center of gravity (CG) height. The two methods, which both appear in international standards, are the Axle Lift method and the Stable Pendulum method. The Stable Pendulum method requires a dedicated swinging platform mechanism*, but it is generally considered to be more accurate than the Axle Lift method. Both methods rely on equations for computing CG height that are based on static balance models of a vehicle tested at various pitch angles. For each method, the accuracy of the resulting CG height computations is a function of the individual measurements needed in the model equations. The individual measurements needed depend on the method used, but they include weights, angles, and distance measurements. A theoretical error analysis study is presented that provides insight into the accuracy of both
Heydinger, Gary, Zagorski, Scott, Bartholomew, Meredith, Andreatta, Dale
Static Rollover Stability Analysis of Heavy Tipper Vehicle2026-26-00901/16/2026
Heavy tipper vehicles are primarily utilized for transporting ores and construction materials. These vehicles often operate in challenging locations, such as mining sites, riverbeds, and stone quarries, where the roads are unpaved and characterized by highly uneven elevations in both the longitudinal and lateral directions of vehicle travel. During the unloading process, the tipper bodies are raised to significant heights, which increases the vehicle's centre of gravity, particularly if the payload material does not discharge quickly. Such conditions can lead to tipper rollover accidents, causing severe damage to life and substantial vehicle breakdowns. To analyse this issue, a study is conducted on the vehicle design parameters affecting the rollover stability of a 35-ton GVW tipper using multi-body simulations in ADAMS software. The tilt table test was simulated to determine the table angle at which wheel lift occurs. Initially, simulations are performed with the rigid body model
Vichare, Chaitanya Ashok, Patil, Sudhir, Gupta, Amit
Driver-in-the-Loop Optimization of Tire-Vehicle Dynamics for Variant Application through Physical Tire Model2026-26-00991/16/2026
Today due to time to market requirements, Original Equipment Manufacturers (OEM) prefers platform modularity for Product Development in Automotive Domain. Money and time being main constraint we need to focus on single platform which can give flavors of different category just by changing Ride height and Tyre and some extra tunable. Taking this as challenge still tyre development for new variant demands lot of time and iterations which can lead to delays in time to market. This study provides a virtual development process using driver in loop Simulator and Multi body dynamics simulation which are real time capable and integrating physical tire models. The proposed alteration introduces ride height changes, weight distribution changes, and center of gravity changes from existing vehicle design. The proposed new vehicle variant also introduces tire change from highway terrain type to all-terrain type as it was intended to deliver some off-roading capabilities, thereby vehicle dynamics
Shrivastava, Apoorv, Asthana, Shivam
Advance Techniques to Optimize Variable Gear Ratio Steering for High Centre of Gravity Vehicles2026-26-00861/16/2026
Vehicles with a high center of gravity (CG) and moderate wheel track, like compact Sport Utility Vehicles (SUVs), have a relatively low Static Stability Factor (SSF) and thus are inherently less stable and more susceptible to rollover crashes. Moreover, to be more maneuverable in highly populated urban areas, a smaller Turning Circle Diameter (TCD) is necessary. Here, Variable Gear Ratio (VGR) steering systems have major benefits over traditional Constant Gear Ratio (CGR) systems in terms of enhancing both roll stability and agility. To adapt VGR steering systems to a particular vehicle dynamic, Full Vehicle (FV) and Driver-in-the-Loop (DIL) simulations are utilized. Using this method, exact calibration is possible according to realistic driving conditions so that the VGR steering C-factor curve is properly tuned for optimal handling in on-center, off-centre, and transitional areas of the Steering Wheel Angle (SWA). Primary performance measures—e.g., SWA gradients at different lateral
Rewale, Pratik, Kopiec, Jakub, Kumar, Deva, Rasal, Shraddhesh, Hussain, Inzamam, Nehal, S B
Design of the BIW Structure for Battery Pack Protection in Case of Side Pole Impact2026-26-00251/16/2026
Electric vehicles (EVs) are becoming more popular than Internal Combustion Engine (ICE) powered vehicles, but their battery and motor components elevate their Gross Vehicle Weight (GVW), posing unique collision risks. Manufacturers strategically mount the high voltage (HV) battery packs under the passenger compartment to lower the Centre of Gravity and shield them from the front impacts. However, side impacts remain a concern, as the battery deformation in such instances could trigger fires or explosions, endangering occupants. To address this, crashworthiness designs adhere to New Car Assessment Program (NCAP) standards, particularly against side pole impact and side mobile barrier impact. Unlike the frontal section of BIW, which typically has larger crush space to absorb the crash energy, extensive design attention is required to the vehicle's side structure to absorb pole impacts without transmitting excessive force to the battery pack. Utilizing aluminium extrusions and sheet
Nivesh, Dharun, Namani, Prasad, Ramaraj, Rajasekar
Architecting ATA 28 with Model-Based Systems Engineering: Center of Gravity Balance and System Performance01-18-03-00151/7/2026
The fuel management system for a fixed-wing aircraft has been developed and explored with the model-based systems engineering (MBSE) methodology for maintaining the center of gravity (CoG) and analyzing flight safety. The system incorporates high-level modeling abstractions that exploit a mix of behaviors and physical detail resembling real-world components. This approach enables analysis for a multitude of system requirements, verification, and failure scenarios at high simulation speed, which is necessary during system definition. Initially, the CoG is maintained by directly accessing the flight deck valves and pumps in both wings and controlling them through the bang-bang control law. In the refinement phase of the fuel system controller, the manual and individual controls of the valves and pumps are replaced with an autonomous fuel transfer scheme. The autonomous scheme achieves no more than a 20 kg difference in fuel between the wings during normal conditions. In the event of
Zaidi, Yaseen, Michalek, Ota
Research and HIL Test of Rear Wheel Steering Control Strategy Based on Zero Sideslip Angle2025-01-732312/31/2025
This paper briefly introduces the vehicle characteristics of four-wheel steering. Based on the parameters of an electric SUV, a linear two-degree-of-freedom vehicle dynamics model is established, and the transfer function of the rear wheel steering angle is derived to keep the sideslip angle at the center of gravity(CoG) constant at zero and proportional to the front wheel steering angle under steady state. The active rear wheel steering control strategy based on zero sideslip angle is established by MATLAB/Simulink, and a co-simulation model is built with CarSim and the HIL test bench to simulate and analyze the proposed control strategy. Subsequently, through classic handling stability test conditions such as the snake test, steering angle step test, and double lane change test, the influence of active rear wheel steering on vehicle dynamic response indicators such as sideslip angle, lateral acceleration, and yaw rate is studied, and the control effect is compared with that of the
Xu, Xiangfei, Qu, Yuan, Liu, Jiabao
Monte Carlo Methods for Evaluating Flight Performance of Sounding Rockets in the International Rocket Engineering Competition2025-36-010612/18/2025
In the launch of sounding rockets, several factors can affect their performance, including uncertainties in aerodynamic design, environmental conditions at the launch site (e.g., wind and temperature), and propulsion-related aspects like the thrust curve and possible deviations. Given these variables, conducting extensive simulations becomes essential to map their influence on the flight. Monte Carlo simulation is a numerical analysis technique that uses random numbers to solve complex problems involving uncertainties and stochastic variables. In rocketry, this method helps analyze the rocket’s flight behavior while accounting for uncertainties in key inputs. In this context, this study presents the Monte Carlo method for simulating university-level sounding rockets, enabling an assessment of the sensitivity of key parameters. To conduct this analysis, five variables were taken into account, including wind, propulsion uncertainties, aerodynamic coefficient uncertainties, and mass
Oliveira Junior, Wilson Luiz de, Fazzolari, Heloise Assis, Paiva Carvalho, Carlos Alberto de
Research on Low-Power Control of Offshore Wind Sail Stabilization Devices Based on Single Pendulum Control Simulation2025-99-013111/11/2025
To tackle persistent operational instability and excessive energy consumption in marine observation platforms under wave-induced disturbances, this paper introduces a novel ultra-low-power stabilization system based on pendulum dynamics. The system employs an innovative mechanical configuration to deliberately decouple the rotation axis from the center of mass, creating controlled dynamic asymmetry. In this behavior, the fixed axis serves as a virtual suspension pivot while the camera payload functions as a concentrated mass block. This configuration generates intrinsic gravitational restoring torque, enabling passive disturbance attenuation. And its passive foundation is synergistically integrated with an actively controlled brushless DC motor system. During platform oscillation, embedded algorithms detect angular motion reversals. In addition, their detection triggers an instantaneous transition from motor drive to regenerative braking mode, and transition facilitates bidirectional
Zhang, Tianlin, Liu, Shixuan, Xu, Yuzhe
Optimizing Forklift Performance Through Multibody Simulation: Analyzing the Role of Tires and Counterweight in De-Rated Capacity2025-28-025411/6/2025
The de-rated capacity of forklifts plays a crucial role in determining their safety, efficiency, and overall performance, particularly when modifications are introduced to meet stringent industrial standards. The term "de-rated capacity" refers to the reduction in a forklift's rated load-carrying capacity caused by various factors, including load center shifts, lifting height, attachment usage, tire types, and counterweight adjustments. This reduction occurs as a safety measure to account for potential instabilities or mechanical limitations when operating under less-than-ideal conditions. Accurate understanding and calculation of de-rated capacity are vital to ensure safe and efficient forklift operation. This research provides a detailed examination of forklift variants, specifically evaluated under the IS 4357:2004 standards [1], to understand the intricate relationship between tire types and counterweight adjustments on the derated capacity. With advanced Multibody Simulations, as
Shende, Kalyani, Shingavi, Shreyas, Hingade, Nikhil
Enhancing Tipper Stability during Descent with Dynamic Angle Adjustment2025-28-027611/6/2025
Tippers transporting loose bulk cargo during prolonged descents are subject to two critical operational challenges: cargo displacement and rear axle lifting. Uncontrolled cargo movement, often involving loose aggregates or soil, arises due to gravitational forces and insufficient restraint systems. This phenomenon can lead to cabin damage, loss of control, and hazardous discharge of materials onto roadways. Simultaneously, load imbalances during descent can cause rear axle lift, increasing stress on the front steering axle, resulting in tire slippage and compromised maneuverability. This study proposes a dynamic control strategy that adjusts the tipper lift angle in real time to align with the descent angle of the road. By synchronizing the trailer bed angle with the slope of the terrain, the system minimizes cargo instability, maintains rear axle contact, and enhances braking performance, including engine and exhaust braking systems. Computational modelling is employed to assess the
Vijeth, Abhishek, Bhosle, Devidas Ashok, Cherian, Roshni, Dash, Prasanjita
Design IQ: An Integrated System for Smart Engineering Metrics2025-28-032711/6/2025
Weight and cost are pivotal factors in new product development, significantly impacting areas such as regulatory compliance and overall efficiency. Traditionally, monitoring these parameters across various stages involves manual processes that are often time-intensive and prone to delays, thereby affecting the productivity of design teams. In current workflows, designers must manually extract weight and center of gravity (CG) data for each component from disparate sources such as CAD models or supplier documents. This data is then consolidated into reports typically using spreadsheets before being analyzed at the module level. The process requires careful organization, unit consistency, and manual calculations to assess the impact of each component on overall system performance. These steps are not only laborious but also susceptible to human error, limiting agility in design iterations. To address these challenges, there is a conceptual opportunity to develop a system that could
Patil, Vivek, Sahoo, Abhilash, Ballewar, Sachin, Chidanandappa, Basavaraj, Chundru, Satyanarayana
Impact of Battery Electric Conversion on Rollover Safety of Large Passenger Buses per UN ECE R6609-13-02-00098/1/2025
The electric conversion of a large passenger vehicle was investigated, in which the internal combustion engine and associated components were replaced by electric powertrain components. As this will have an influence on the rollover safety performance of the vehicle, compliance to the requirements of UN ECE Regulation No.66 was assessed. The vehicle geometry was captured through physical inspection. The unladen kerb mass of the vehicle was experimentally determined as 10660 kg. This mass excludes the mass of occupants as the vehicle is not fitted with occupant restraints. The location of the center of gravity was estimated using a representative CAD model. The center of gravity is located at a distance of 3580 mm behind the front axle and at a height of 1195 mm above the ground. An implicit nonlinear finite element (FE) analysis was conducted to quantify the energy absorption capability of a rollover hoop. This value was calculated as 5.65 kJ for a single rollover hoop and 67.80 kJ for
Raats, Daniel James, Venter, Gerhard, Bredell, Johann
Balancing Machines: Tooling Design CriteriaARP4163A (Current)7/9/2025
This document establishes general design criteria, tolerances, and limits of application for tooling, fixtures, and accessories for mounting and driving gas turbine engine rotors on horizontal and vertical balancing machines.
EG-1A Balancing Committee
Road Surface Adaptive Stationary Steering Coordinated Control of Four-Wheel Hub Motor Vehicles2025-01-50314/29/2025
The wheel hub motor–driven electric vehicle, characterized by its independently controllable wheels, exhibits high torque output at low speeds and superior dynamic response performance, enabling in-place steering capabilities. This study focuses on the control mechanism and dynamic model of the wheel hub motor vehicle’s in-place steering. By employing differential torque control, it generates the yaw moment needed to overcome steering resistance and produce yaw motion around the steering center. First, the dynamic model for in-place steering is established, exploring the various stages of tire motion and the steering process, including the start-up, elastic deformation, lateral slip, and steady-state yaw. In terms of control strategy, an adaptive in-place steering control method is designed, utilizing a BP neural network combined with a PID control algorithm to track the desired yaw rate. Additionally, a control strategy based on tire/road adhesion ellipse theory is developed to
Huang, Bin, Cui, Kangyu, Zhang, Zeyang, Ma, Minrui
Necessity of Body Torsional Rigidity of Personal Mobility Vehicles (PMVs) with an Inward Tilting Mechanism2024-32-00134/18/2025
In traditional four-wheeled automobiles, the imbalance between the roll moment, which is the product of the centrifugal force during a turn acting on the center of gravity and the height of the center of gravity, and roll stiffness, which is the product of the left-right difference in tire vertical load and the tread width and commonly used among automotive suspension engineers, of the front and rear sections necessitates body torsional rigidity. However, there is a lack of specific cases and guidelines for constructing the body structure of three-wheeled PMVs (Personal Mobility Vehicles) with a tilting mechanism from the perspective of vehicle dynamics characteristics. In this paper, the basic considerations related to the dynamics of such three-wheeled PMVs are investigated. We use the term “torsional rigidity” to refer to the stiffness as the torsional deformation of the body itself, and the term “roll stiffness” to refer to the moment that counteracts the roll moment during a turn
Haraguchi, Tetsunori, Kaneko, Tetsuya
Heavy Tracked Vehicles: Preliminary Design for Mobility2025-01-83374/1/2025
Modern military operations prove that increased terrain mobility is critical for heavy tracked vehicles’ (HTVs) survivability and lethality. HTV major system packaging as a component of preliminary design with many physical constraints and assumptions poses great challenges for mobility. This paper develops an approach and a method that accounts for such constraints/assumptions and optimizes the packaging of the HTV system assembly, including vehicle armor, armament and munition, powertrain, and fuel tanks. The optimization purpose is to accommodate the center of gravity for improving ground pressure distribution and then reducing the sinkage. This work is based on a literature review and combines numerous techniques rooted in Western literature and Eastern Soviet- and post-Soviet-era literature. The optimization process is developed using a genetic algorithm. The Mean Relative Design (MRD) parameter is proposed to study the average system rearrangement (i.e., re-packing) that is
Vardi, Haggay, Vantsevich, Vladimir, Gorsich, David
Stability Control for Distributed Drive Electric Vehicles Using Particle Filter and Fuzzy Integral Sliding Mode Control2025-01-88114/1/2025
The Distributed Drive Electric Vehicles (DDEVs) offer advantages such as independently controllable driving and braking forces at each wheel, rapid response, and precise control. These features enable effective electronic stability control (ESC) by appropriately distributing torque across each wheel. However, traditional ESC systems typically employ single-wheel hydraulic differential braking, failing to fully utilize the independent torque control capabilities of DDEVs. This study proposes a hierarchical control strategy for distributed driving and braking ESC based on particle filter (PF) and fuzzy integral sliding mode control (FISMC). First, the vehicle state estimation layer uses a three-degree-of-freedom vehicle model and the PF to estimate sideslip angle and vehicle speed. Next, the target torque decision layer includes a target speed tracking controller and a yaw moment decision controller. The yaw moment decision controller uses the FISMC to determine additional yaw moment by
Li, Xiaolong, Zheng, Hongyu, Kaku, Chuyo
Research on Seakeeping Performance of Amphibious Rescue Vehicle Based on CFD2025-01-87954/1/2025
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
A Torque Distribution Strategy for the Six-Wheeled Lunar Rover2025-01-83084/1/2025
As a crucial tool for lunar exploration, lunar rovers are highly susceptible to instability due to the rugged lunar terrain, making control of driving stability essential during operation. This study focuses on a six-wheel lunar rover and develops a torque distribution strategy to improve the handling stability of the lunar rover. Based on a layered control structure, firstly, the approach establishes a two-degree-of-freedom single-track model with front and rear axle steering at the state reference layer to compute the desired yaw rate and mass center sideslip angle. Secondly, in the desired torque decision layer, a sliding mode control-based strategy is used to calculate the desired total driving torque. Thirdly, in the torque distribution layer, the optimal control distribution is adopted to carry out two initial distributions and redistribution of the drive torque planned by the upper layer, to improve the yaw stability of the six-wheeled lunar rover. Finally, a multi-body dynamics
Liu, Pengcheng, Zhang, Kaidi, Shi, Junwei, Yang, Wenmiao, Zhang, Yunqing, Wu, Jinglai
A Steering Control Method Applicable to an Eight-Wheeled Planetary Laboratory2025-01-83054/1/2025
In future planetary exploration missions, the Eight-Wheeled Planetary Laboratory (EWPL) will have sufficient capacity for tasks but will experience significant lateral slips during high-speed turns due to its large inertia. Modern technology allows for independent steering of all eight wheels, but controlling each wheel's steering angle is key to improving stability during turns. This paper introduces a novel rear-axle steering feed-forward controller to reduce sideslip. First, a mathematical model for the vehicle's steering is established, including kinematic equations based on Ackermann steering. Feed-forward zero side-slip control is applied to the third and fourth axles to counteract the side-slip angle of the center of mass. A multi-body dynamics model of the EWPL is then built in Chrono to evaluate the turning radius and optimize steering angle ratios for the rear axles. Finally, a steady-state cornering simulation on loose terrain compares the performance of the proposed
Liu, Jun, Zhang, Kaidi, Shi, Junwei, Yang, Wenmiao, Zhang, Yunqing, Wu, Jinglai
Optimized Design and Analysis of a High-Performance, Track-Focused Quad Bike for the Indian Market2025-28-00612/7/2025
This paper presents a complete approach to the optimized design and analysis of a trach-focused quad bike suitable for the Indian market. The process of design integrates several analytical factors, including driver ergonomics, aesthetics, and strategic component placement, to establish optimum vehicle dimensions. The primary objective is to address the unique demands of the Indian terrain and user preferences through ensure comfort, functionality, and visual appeal. The selection process for tires and suspension geometry is precisely conducted with the advanced OptimumKinematics software. This optimization provides greater performance and stability that the vehicle can accurately manage a variety of road conditions. The space frame chassis of a vehicle’s core structure features, engineered to minimalize tubing and facilitate ease of fabrication, contributing to both structural integrity and weight reduction. A robust 600cc four-cylinder engine is selected that emphasizing an optimal
Thanikonda, Praveen Kumar, Shaik, Amjad, Tappa, Raju, Ratlavath, Ramu, Navar, Adarsh, Challa, Ajith Kumar
Integrated Control of Intelligent Vehicle Driving Stability Using Three-Dimensional Phase Space10-09-01-000210/16/2024
To enhance vehicle dynamic stability during driving, we developed a three-dimensional phase space model that incorporates the sideslip angle of center of mass, yaw rate, and lateral load transfer rate. This model enabled real-time evaluation and active control of vehicle stability. First, longitudinal and lateral controllers were implemented to ensure precise vehicle trajectory. Second, a hierarchical control strategy was designed to actively manage the desired sideslip angle, yaw rate, and roll angle based on the vehicle’s destabilizing conditions, thereby maintaining the vehicle within a stable state space. We simulated and tested the stability analysis methods and integrated control strategies for both cars and trucks under DLC (double lane change) and CDC (circular driving condition) scenarios using joint simulations with CarSim/TruckSim and Simulink. The proposed integrated stability control strategy, which combined MPC-based trajectory tracking with direct yaw moment control and
Lai, Fei, Xiao, Hao, Huang, Chaoqun
829 Guidance for Wireless Use of COTS Crew DevicesARINC829 (Current)7/24/2024
This standard provides guidance on the preferred methods for establishing wireless connectivity and security for EFB devices. The Wireless Access Point (WAP) may be connected to an Aircraft Interface Device (AID) and/or the Inflight Entertainment System (IFE). Passenger devices are out of scope for this standard.
Airlines Electronic Engineering Committee
858P1-1 Internet Protocol Suite (IPS) for Aeronautical Safety Services, Part 1, Technical RequirementsARINC858P1-1 (Current)7/2/2024
ARINC 858 Part 1 defines the airborne data communication network infrastructure for aviation safety services using the Internet Protocol Suite (IPS). ARINC 858 builds upon ICAO Doc 9896, Manual on the Aeronautical Telecommunication Network (ATN) using Internet Protocol Suite (IPS) Standards and Protocol. IPS will extend the useful life of data comm services presently used by operators, e.g., VDL, Inmarsat SBB, Iridium NEXT, and others. It represents the evolutionary path from ACARS and ATN/OSI to the end state: ATN/IPS. ARINC 858 includes advanced capabilities such as aviation security and mobility. This product was developed in coordination with ICAO WG-I, RTCA SC-223, and EUROCAE WG-108.
Airlines Electronic Engineering Committee
Reference Velocity Estimation with Variable Gain Based on Powertrain Dynamics for Production Hybrid Electric Vehicle2024-01-21474/9/2024
Reference velocity (i.e. the absolute velocity of vehicle center of gravity) is a key parameter for vehicle stability control functions as well as for the powertrain control functions of hybrid electric vehicle (HEV). Most reference velocity estimation methods employ the vehicle kinematic and tire dynamic equations to construct high order linear or nonlinear model with a set of parameters and sensor measurements. When using those models, delicate algorithm should be designed to prevent the estimates from deviating along with the increase of nonlinearity, modeling error and noise that introduced by high order, parameter approximation, and sensor measurements, respectively. Alternatively, to improve the function robustness and calibration convenience, a straightforward online estimation method is developed in the paper by using a second-order powertrain dynamic model that only need a small set of vehicle parameters and sensor values. First, the HEV powertrain dynamic model is established
Li, Huan, Liu, Xuewu, Wang, Jinhang, Chen, Lihua, Xu, Yin, Wu, Meng
Spectrum-Based Method for Fatigue Damage under Excitation of Sinusoidal Sweeps for Automotive Systems2024-01-22604/9/2024
Vibration from a mechanical system not only produces unwanted noises annoying to people around, but also runs a risk of fatigue failure that would actually hinder its functionality. There are several forms of vibration depending on the sources of excitation forms. Mechanical systems with rotating components can be subjected to sinusoidal excitation due to the fact the center of mass is not perfectly aligned with the rotating axis. If the rotating speed is strictly ramping up or ramping down, this can create an excitation whose frequency is changing with time in a frequency range corresponding to the speeds swept. Compared with a single sinusoidal excitation, the issue with fatigue at swept sinusoidal excitation, is that as it sweeps through a wide frequency range, some swept frequencies will definitely coincide with the natural frequencies of the system. Certainly, the stress response exactly at the resonant frequency becomes the highest and could account for a lot of fatigue damage
Yang, Zane, Zhou, Lin
Accuracy of 2016-2022 EDRs in IIHS Crash Tests2024-01-28904/9/2024
Event data recorders (EDRs) were harvested and imaged after Insurance Institute for Highway Safety (IIHS) 56 km/hr frontal and 64.4 km/hr frontal offset crashes of 15 different brands of 2016-2022 vehicles. The speed and delta-V in the EDR were compared to reference instrumentation. Speed data was accurate within the generally accepted range of +/-4%. The 40% overlap tests had generally similar vehicle kinematics, and their delta-Vx data was accurate. However, there was a much greater variance in the small (25%) overlap tests. Some outliers in the small overlap delta-Vx tests required further analysis using overhead video analysis. The video analysis more closely matched the EDR recorded values. These offset tests create significant post-crash rotation, and both EDR and IIHS instrumentation were affected by their location away from the center of gravity. The Y-axis was affected much more than the X-axis. The data scatter in Y-axis was significant, particularly in the IIHS reference
Ruth, Richard, King, Charles, Rich, Andrew, Sadrnia, Hamed
Multi-Objective Optimization of Occupant Survival Space of a Medium-Duty Vehicle under Rollover Condition2024-01-22634/9/2024
Due to the high center of gravity of medium-duty vehicles, rollover accidents can easily occur during high-speed cornering and lane changes. In order to prevent the deformation of the body structure, which would restrict the survival space and cause compression injuries to occupants, it is necessary to investigate methods for mitigating these incidents. This paper establishes a numerical model of right-side rollover for a commercial medium-duty vehicle in accordance with ECE R66 regulations, and the accuracy of the model is verified by experiment. According to the results, the material and size parameters of the key components of the right side pillar are selected as design variables. The response result matrix was constructed using the orthogonal design method for total mass, energy absorption, maximum collision acceleration, and minimum distance from the survival space. A multi-objective optimization of 25 sets of sample points was performed using a multi-factor weight analysis
Zhang, Jiangfan, Zou, Xiaojun, Yuan, Liu-kai, Zhang, Tang-yun, Wang, Tao, Wang, Liangmo
Telescope Baffle Mass Simulator Design Using Shape Optimization2024-01-19343/5/2024
A case study of an application of Shape optimization techniques in the design of a mass simulator has been presented. A simple mass Simulator is to be designed as a replacement for a Telescope Baffle Mass for testing purposes. The simulator is made of simple plate structures like flat plates and cylindrical plates joined together. The overall mass, location of center of gravity and first few modes of the simulator need to be close to the Telescope Baffle, it is replacing. This ensures that the Simulator is a good replacement for the Telescope Baffle both in statics and dynamics performance. Shape Optimization techniques using approximate direct linearization method of MSC/Nastran software have been used to fine-tune the baseline Simulator design to achieve target properties of mass, cg, frequencies, etc.
Krishna, Murali MR
Simulation Methodology Development for Vibration Test of Bus Body Structure Code AIS-153:20182024-26-02491/16/2024
A bus is integral part of public transportation in both rural and urban areas. It is also used for scheduled transport, tourism, and school transport. Buses are the common mode of transport all over the world. The growth in economy, the electrification of public transport, demand in shared transport, etc., is leading to a surge in the demand for buses and accelerating the overall growth of the bus industry. With the increased number of buses, the issue of safety of passengers and the crew assumes special importance. The comfort of driver and passenger in the vehicle involves the vibration performance and therefore, the structural integrity of buses is critically important. Bus safety act depicts the safety and comfort of bus operations, management of safety risks, continuous improvement in bus safety management, public confidence in the safety of bus transport, appropriate stakeholder involvement and the existence of a safety culture among bus service providers. In order to provide
Bijwe, Vilas B., Mahajan, Rahul, Vaidya, Rohit, Patel, Kaustubh, Hiwale, Diwakar, Walke, Abhijit Ashok
A Novel Approach for Combi Braking System Design Considering Tire’s Nonlinear Behavior2024-26-00581/16/2024
The standard usage of Combined Braking System (CBS) in lower cc/power 2-wheeler vehicles serves to reduce stopping distance and improve braking stability. The CBS system achieves this by engaging both the front and rear wheel brakes, taking advantage of the high load transfer characteristic during 2-wheeler braking. However, the current design of the CBS system relies on linear system analysis, based on vehicle geometry, load distribution, and tire-road friction. This approach overlooks the non-linearities inherent in braking dynamics, such as tire behavior and dynamic Center of Gravity (CoG) location. Consequently, the current CBS design methodology exhibits limitations, particularly in extreme scenarios where wheel lock-up may occur, such as on low friction surfaces or during panic braking. This paper proposes the incorporation of tire non-linearities into the design of CBS systems using Pacejka’s tire model. Initially, calculations are performed to optimize the braking
Khandekar, Piyush, Badiger, Kartik, Gautam, Ashish, Soni, Lokesh
Impact of Toe and Thrust Angle Misalignment on Roll Behaviour of a Heavy Commercial Road Vehicle2024-26-00561/16/2024
Heavy Commercial Road Vehicles (HCRVs) may be more susceptible to rollover incidents due to their higher centre of gravity position than passenger vehicles, and rollover is one of the significant causes of HCRV accidents. Therefore, variation in vehicle roll behaviour becomes crucial to the safety of an HCRV. Toe misalignment is a commonly observed phenomenon in HCRVs, and studying its impact on roll behaviour is important. In this study, the impact of the symmetric toe and thrust misalignment on the roll behaviour of an HCRV is analysed using IPG TruckMaker®, a vehicle dynamics simulation software. A ramp steer manoeuvre was used for the simulations, and the toe misalignment on a wheel was chosen from the range [-0.21°, 0.21°]. Variation in roll behaviour was quantified using the steering wheel angle at which one-wheel lift-off (OWL) occurred (SWAL). Additionally, an analytical model was formulated to predict OWL and the model predictions were compared with the results from IPG
Chandran, Amarchand, Grandhe, Roshan, Mukhopadhyay, Arko, Sharma, Mitanshu, Shankar Ram, C S
SUV Multi-Link Rigid Axle Control Links Optimization for Ride and Handling Improvement2024-26-00481/16/2024
In automotive world role of suspension system is to absorb vibrations from the road, and to provide stability while vehicle is going over bumps or uneven roads, cornering, acceleration and braking etc. For body on frame SUVs which are typically characterized by high center of gravity, it is quite critical to find best balance in ensuring stability of the vehicle and having comfortable ride performance. Rigid axle rear suspension is quite a typical choice in such vehicles, wherein lower and upper control links are two important components subjected to lateral, longitudinal, and vertical loads. These links allow the vehicle to move smoothly throughout the entire range of suspension travel. Kinematics and compliance optimization of these links is a major factor in definition of ride-handling performance of the vehicle. The present study describes key challenges and methodology to define position as well as orientation of control links, where-in multiple inter-related handling and comfort
Hussain, Inzamam, Jani, Harshil, Rasal, Shraddhesh, Asthana, Shivam, Ahire, Manoj, Jadhav, Prashant, Lenka, Visweswara, Vellandi, Vikraman
633-5 AOC Air-Ground Data and Message Exchange FormatARINC633-5 (Current)1/9/2024
The purpose of ARINC 633 is to specify the format and exchange of Aeronautical Operational Control (AOC) communications. Examples of ARINC 633 AOC Structures/Messages include: Flight Plans, Load Planning (i.e., Weight and Balance and Cargo Planning Load Sheets), NOTAMs, Airport and Route Weather data, Minimum Equipment Lists (MEL) messages, etc. The standardization of AOC messages enables the development of applications shared by numerous airlines on different aircraft types. Benefits include improved dispatchability and reduce operator cost. ARINC 633 is a complete definition of AOC message sets used in commercial aviation with XML schema definitions included.
Airlines Electronic Engineering Committee
Matching and Optimization Design of Electric Drive Assembly Mounting System of Electric Vehicle2023-01-700210/30/2023
The design method for the powertrain mounting system in internal combustion engine vehicles is well-established. Electric vehicles experience higher vibration frequencies and more significant transient responses when accelerating or braking than fuel vehicles due to their high speed and fast response. Therefore, the design of the electric drive assembly mounting system requires further development. The modeling of electric drive assembly mounting systems often neglects the mounting bracket’s influence, which significantly affects the center of mass and rotational inertia of the electric drive assembly. This paper examines the effect of the mounting bracket in the electric drive assembly mounting system. It establishes a mathematical model with six degrees of freedom for the mounting system, considering the mounting bracket. By comparing the natural characteristics and the transient response, it is discussed whether the mass of the mounting bracket greatly influences the system. Further
Zhang, Lijun, Wang, Yifan, Meng, Dejian, Liu, Dengcheng, Zhou, Xiao Ming
Understanding Head Injury Risks during Car-to-Pedestrian Collisions Using Realistic Vehicle and Detailed Human Body Models2022-22-00066/27/2023
Traumatic brain injury (TBI) is the leading cause of death and long-term disability in road traffic accidents (RTAs). Researchers have examined the effect of vehicle front shape and pedestrian body size on the risk of pedestrian head injury. On the other hand, the relationship between vehicle front shape parameters and pedestrian TBI risks involving a diverse population with varying body sizes has yet to be investigated. Thus, the purpose of this study was to comprehensively study the effect of vehicle front shape parameters and various pedestrian bodies ranging from 95th percentile male (AM95) to 6 years old (YO) child on the dynamic response of the head and the risk of TBIs during primary (vehicle) impact. At three different collision speeds (30, 40, and 50 km/h), a total of 36 car-to-pedestrian collisions (CPCs) were reconstructed using three different vehicle types (Subcompact passenger sedan, mid-sedan, and sports utility vehicle (SUV)) and four distinct THUMS pedestrian finite
Gunasekaran, Kalish, Islam, Sakib Ul, Mao, Haojie
End-of-Line Vehicle Driveline Balancing Process Design and Improvement, and Variability in the Influence Method2023-01-50366/23/2023
Automotive driveline imbalance is a result of rotating components or assemblies being manufactured with their centers of mass not being coincident with their centers of rotation. For vehicle mass production, an end-of-line (EOL) driveline balancing process may be required, depending on vehicle sensitivity and component control costing. In this investigation, the process and facility design for an EOL automotive driveline balancing process is outlined, including important considerations in the measurement configuration of the balancing facility. Initial results from prototype vehicle testing with conventional influence balancing techniques, based on commercially available equipment, are given. The role of the influence coefficient in the balancing process and of car-to-car variability in the influence coefficient were investigated. An equation for the influence coefficient was derived, providing an improved understanding of the nature of the influence coefficient, along with sources of
Leslie, Andrew, Baddeley, Viv, French, David K.
Horizontal Balancing Systems - Isolating Repeatability Issues in Challenging ApplicationsARP6911 (Current)6/5/2023
This SAE Aerospace Recommended Practice will serve as a practical resource that offers guidance to both the machine operator and process engineer for isolating the source(s) of non-repeatability in measured unbalance data. The content of this standard addresses: Machine capability to achieve the specified unbalance tolerances and repeat within those tolerances. Tooling capability to repeat within the specified unbalance tolerances. Rotor characteristics that may preclude repeating within the required unbalance tolerances.
EG-1A Balancing Committee
Design, Material Selection, Simulation and Manufacturing of ROPS and FOPS for Motor Grader2023-28-13485/25/2023
Motor grader is self-propelled, versatile machine widely used for road construction and maintenance in mining and construction applications. It required working in rugged terrain with uneven and slippery surfaces. Probability of rollover in motor grader is more due to the vehicle profile and high centre of gravity. In light of the above, Roll over Protective Structure (ROPS) is essential to safe guard the operator from any fatal injuries / life during the operation of the equipment at different terrain conditions. Considering DGMS (Directorate of General Mines and safety) requirements, a rugged two post Rollover Protective Structure (ROPS) was designed as per ISO 3471 criteria for ROPS and Falling object Protection Structure (FOPS) as per ISO 3449 Material selection for ROPS and FOPS is one of significant factor in design process by meeting the design criteria. It should have dual characteristic, firstly, it is expected to tough enough to withstand sudden impact forces. Secondly, it
Varadaraj, Kumar, hs, Satish Chandra
Development of Inverter Drive Unit for Battery Electric Vehicle2023-01-05284/11/2023
Toyota Motor Corporation has developed a new battery electric vehicle (BEV) on the dedicated e-TNGA platform for BEVs, which was designed to lower the center of gravity of the vehicle and increase body stiffness. In addition to a full-time 4WD system, another feature of this new BEV is its pleasurable driving experience. A new inverter drive unit was developed for this system. Unlike the previous inverter, the advantage of the new inverter is that it is small enough to be mounted inside the transaxle housing, thereby contributing to the availability of interior and luggage space. The temperature rise of the power semiconductors in the inverter was reduced considerably by the development of a new power semiconductor for BEVs. This enables a parallel layout of two power semiconductors instead of three. The components of the inverter were also downsized. A coreless current sensor was adopted, and capacitors were developed with significantly lower capacitance. The rear inverter adopts
Yuichi, Shimo, Kanzaki, Takao, Yanagi, Takashi, Goto, Yukio, Kurihara, Takashi, Kobayashi, Masayoshi
Trajectory Planning on Autonomous Truck with Dual-Modular Chassis Using Artificial Potential Field and Polynomial2023-01-06904/11/2023
Autonomous truck with modular chassis has the characteristics of high driving flexibility and strong load capacity. It can be equipped with different numbers of modular chassis according to the task requirements. The application of autonomous truck can solve the problems of traffic accidents and shortage of drivers effectively, which is the development trend of trucks in the future. For the collision-free trajectory planning problem of dual-modular chassis autonomous truck, this paper designs a hierarchical local trajectory planner that combines the artificial potential field method with polynomial curve fitting method. This planner plans the center of mass trajectory firstly, and then generates the modular chassis trajectories according to the position relationship between the center of mass and the chassis. The center of mass local trajectory cluster satisfying the environment constraints and truck motion constraints is obtained by polynomial curve fitting method for sampling the
Liu, Tao, Shen, Yanhua, Wang, Haoshuai, Liu, Zuyang
An Autonomous Steering Control Scheme for Articulated Heavy Vehicles Using - Model Predictive Control Technique2023-01-06584/11/2023
This article presents an autonomous steering control scheme for articulated heavy vehicles (AHVs). Despite economic and environmental benefits in freight transportation, lateral stability is always a concern for AHVs in high-speed highway operations due to their multi-unit vehicle structures, and high centers of gravity (CGs). In addition, North American harsh winter weather makes the lateral stability even more challenging. AHVs often experience amplified lateral motions of trailing vehicle units in high-speed evasive maneuvers. AHVs represent a 7.5 times higher risk than passenger cars in highway operation. Human driver errors cause about 94% of traffic collisions. However, little attention has been paid to autonomous steering control of AHVs. To improve the directional performance of AHVs under a high-speed lane-change maneuvers, an autonomous steering control scheme is proposed for a tractor/semi-trailer using a model predictive control (MPC) technique, which controls the steering
Sharma, Tarun, He, Yuping, Huang, Wei
Items per page:
1 – 50 of 876