Browse Topic: Suspension systems

Items (3,589)
The merging problem in the highway merge zone has been a research focus in the field of transportation for a long time. The rise of Connected and Automated Vehicles (CAVs) provides the potential to improve traffic flow efficiency, alleviate congestion and handle safety issues. However, existing two-dimensional merging strategies are facing challenges such as high computational complexity and the inevitable traffic oscillations during merging, which hinder the stability of traffic flow and fail to meet the dynamic requirements of merging control. To address these issues, this study proposes a distributed control strategy for CAVs in highway merge scenarios. Firstly, a virtual rotation method is designed to transform the merging problem of two different lanes into a car-following problem of a virtual platoon, and a virtual leader vehicle is introduced, to reduce computational complexity and determine vehicle sequencing. Based on this method, a Spring Cooperative Merging System (SCMS) is
Liu, YandanQu, Xu
The effectiveness of the negative suspension structure (NSS) in isolating the driver’s seat vibrations has been demonstrated based on the seat’s model or vehicle’s one-dimensional dynamic model. To fully assess the effectiveness and stability of the seat’s NSS (S-NSS) on different models of vehicles, the three-dimensional models of the vibratory rollers (VR), heavy trucks (HT), and passenger cars (PC) have been built to assess the effectiveness of S-NSS compared to the seat’s passive suspension (S-PC) and seat’s control suspension (S-CS). The effectiveness of S-NSS is then investigated under all operating conditions of vehicles. The investigation results indicate that under a same simulation condition, S-NSS improves the ride comfort and health of the driver better than both S-PS and S-CS on all VR, HT, and PC. However, the effectiveness of S-NSS on PC is lower than on both VR and HT while the effectiveness of S-CS on PC is better than on both VR and HT. Besides, the effectiveness of S
Su, BeibeiWang, QiangSong, Fengxiang
Noise, Vibration, and Harshness (NVH) simulations of vehicle bodies are crucial for assessing performance during the design phase. However, these simulations typically require detailed computer-aided design (CAD) models and are time-consuming. In the early stages of vehicle development, when only high-level vehicle sections are available, designing the body-in-white (BIW) structure to meet target values for bending and torsional stiffness is challenging and often requires multiple iterations. To address these challenges, this study deploys a reduced-order beam modelling approach. This method involves identifying the beam-like sections and major joints within the BIW and calculating their sectional properties (area, area moments of inertia along the plane’s independent axes, and torsion constant). These components form a simplified skeleton model of the BIW. Load and boundary conditions are applied to the suspension mount locations at the front and rear of the vehicle, and torsional and
Khan, Mohd Zishan AliThanapati, AlokDeshmukh, Chandrakant
Due to stringent emission norms, all OEMs are shifting focus from Internal combustion engine (ICE) to Electric vehicle (EV). NVH refinement of EVs is challenging due to less background noise in EVs in comparison with ICE vehicles. Motor whine noise is perceived inside cabin till the speed of 20 kmph. Vehicle is powered by electric powertrain (EPT). Electric powertrain is connected to the subframe with the help of three powertrain mounts. Subframe is connected to the body with the help of four mounts. With the help of Transfer Path Analysis (TPA), it is identified that the noise is structure borne and the dominant path is identified. By optimizing the stiffness of the EPT mounts, the structure borne noise levels are reduced. But reducing the stiffness of EPT mount deteriorated the road noise levels. The reason behind deterioration of road noise is investigated. The performance of double isolation of EPT is compared with single isolation of EPT with respect to both road and motor noise
S, Nataraja MoorthyRao, Manchi VenkateswaraRaghavendran, PrasathSelvam, Ebinezer
Customers are expecting higher level of refinement in electric vehicle. Since the background noise is less in electric vehicle in comparison with ICE, it is challenging for NVH engineers to address even minor noise concerns without cost and mass addition. Higher boom noise is perceived in the test vehicle when driven on the coarse road at a speed of 50 kmph. The test vehicle is rear wheel driven vehicle powered by electric motor. Multi reference Transfer Path Analysis (TPA) is conducted on the vehicle to identify the path through which maximum forces are entering the body. Based on the findings from TPA, solutions like reduction in the dynamic stiffness of the suspension bushes are optimized which resulted in reduction of noise. To reduce the noise further, Operational Deflection Shape (ODS) analysis is conducted on the entire vehicle to identify the deflection shapes of all the suspension components and all the body panels like floor, roof, tailgate, dash panel, quarter panel and
S, Nataraja MoorthyRao, Manchi VenkateswaraRaghavendran, PrasathSelvam, Ebinezer
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, BoshiLi, LiangLiao, YinshengLv, HaijunQu, WenyingHu, ZhimingSun, Yue
Hydropneumatic Struts (HPS) are widely implemented in automobile, aerospace, and construction industries, mainly for the purpose of vibration and shock absorption. The HPS design with integrated gas–oil chamber is relatively more compact and robust, while mixing gas and oil inside the HPS generates gas–oil emulsion and more nonlinearities. This study formulated a nonlinear analytical model of the compact HPS with gas–oil emulsion, considering the real gas law and pressure-dependent LuGre friction model. The polytropic version of the van der Waals (vdW) method for real gas is applied to represent the thermodynamic behavior of nitrogen. The experimental data were collected at a near temperature of 30°C with three charging pressures under excitations in the frequency range of 0.5–6 Hz, considering two flow connection configurations between chambers as one- and two-bleed orifice. The nonlinear behavior of the gas volume fraction of the emulsion was identified based on peak strut velocity
Seifi, AbolfazlYao, YumengYin, YumingMoore, MasihRakheja, Subhash
This article presents a height control method for air suspension systems, which are influenced by strong nonlinearity and multiple coupling factors, based on model-free adaptive control (MFAC) using full-form dynamic linearization (FFDL). To address the impact of different damping coefficients of the shock absorber on the height control effect, an improved genetic algorithm is employed to globally optimize the relevant parameters involved in the design of the control law, thereby enhancing the height control performance. The precision of modeling the air suspension system has a direct impact on the simulation of both static and dynamic vehicle models, as well as the accuracy of height control. In this article, an equivalent thermodynamic model of the air suspension system is established based on the principle of energy conservation for height control research. Considering the nonlinearity of the air suspension system and the need to make additional assumptions before modeling, a MFAC
Yao, JiyangWu, GuangqiangWu, JianYang, YuchenYan, Xudong
The SAE Formula, a national stage of the international competition, consists of a student project at universities in Brazil that seeks to encourage engineering students to apply the theoretical knowledge obtained in the classroom to practice, dealing with real problems and difficulties in order to prepare them for the job market. The SAE Formula prototype is developed with the intention of competing in the SAE national competition, where teams from various universities in Brazil meet to compete and demonstrate the projects developed during the year. Focusing on the vehicle dynamics subsystem, which can be divided into the braking, suspension, and steering systems of a prototype, the steering system includes main mechanical components such as the front axle sleeves, wheel hub, steering arm, steering column, rack, wheel, and tire. All these components work together with the suspension systems, including suspension arms, “bell crank,” and spring/shock absorber assembly. These components
Rigo, Cristiano Shuji ShimadaNeto, Antonio Dos Reis De FariaGrandinetti, Francisco JoseCastro, Thais SantosDias, Erica XimenesMartins, Marcelo Sampaio
This paper aims to describe a quarter-car suspension test bench automation process to be utilized in an academic environment. The project is made up of pneumatic system modeling and control system design. An analysis of the bench’s pneumatic system is carried out. This pneumatic system is composed of a pneumatic actuator and a proportional directional control valve, which are responsible for generating the road profile. It is proposed a model to compensate the non-linearities present in the pneumatic system measurement process and the disturbances caused by the under test suspension system, as well as a control strategy for small displacements of the load through linear control approaches, which provide the necessary flexibility to directly influence the parameters affecting the dynamics of the excitation system platform’s displacement, thereby reducing the complexity of the controller design to be adopted. Furthermore, analyses are conducted on the effectiveness of the control in
Siqueira, Matheus AmaralGomes, Pedro CarvalhoTeixeira, Evandro Leonardo SilvaFortaleza, Eugênio Libório FeitosaMorais, Marcus Vinicius Girão
Autonomous vehicles for mining operations offer increased productivity, reduced total cost of ownership, decreased maintenance costs, improved reliability, and reduced operator exposure to harsh mining environments. A large flow of data exists between the remote operation and the ore haul vehicle, and part of the data becomes information for the maintenance sector which it monitors the operating conditions of various systems. One of the systems deserving attention is the suspension system, responsible for keeping the vehicle running and within a certain vibration condition to keep the asset operational and productive. Thus, this work aims to develop a digital twin-assisted system to evaluate the harmonic response of the vehicle’s body. Two representations were created based on equations of motion that modeled the oscillatory behavior of a mass-damper system. One of the representations indicates a quarter of the ore transport truck’s hydraulic system in a healthy state, called a virtual
Rosa, Leonardo OlimpioBranco, César Tadeu Nasser Medeiros
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 FabianTerra, Rafael Tedim
A serious problem of public healthcare around the world is the number of road vehicle accidents, every year almost 1,3 million people die and approximately 20 to 50 million people suffer a non-fatal accident because of a road vehicle accident [1]. As a result of that, in 2021 the World Health Organization stated the “The Second Decade of Action for Road Safety”, which the goal is to prevent at least 50% of deaths and injuries due traffic by 2030. To achieve this goal, the automobile companies have invested in technology and products that can enhance vehicle safety. Despite exist some control systems able to reduce roll, and consequently the roll over, such as active suspension, semi-active suspension, and stability control systems, none of them have as main purpose reduce the number of rollovers. The following study aims to examine the effects of an active anti roll bar, to improve the vehicle dynamics during corners and reduce the risk of a rollover by reducing the roll of the sprung
Gomes, Pedro CarvalhoTeixeira, Evandro Leonardo SilvaMorais, Marcus Vinicius GirãoFortaleza, Eugenio Liborio FeitoraSantos Gioria, Gustavo
The SAE Formula prototypes are developed by students, where in the competition, various aspects of project definitions are evaluated. Among the factors evaluated for scoring is the braking system, in which the present work aims to present the development and design of the braking system of a vehicle, prototype of Formula SAE student competition. As it is a project manufactured mostly by students, where the chassis, suspension system, electrical, transmission and powertrain are developed, it is important to first pass the static and safety tests, where the brakes of the four wheels are tested during deceleration at a certain distance from the track. To enable such approval and also to demonstrate, for the competition judges, the veracity of the system’s sizing, all the parameters and assumptions of the choice of the vehicle’s braking system are presented, thus ensuring their reliability, efficiency and safety. Using drawing and simulation software such as SolidWorks and Excel for
Gomes, Lucas OlenskiGrandinetti, Francisco JoséMartins, Marcelo SampaioSouza Soares, Alvaro ManoelReis de Faria Neto, AntônioCastro, Thais SantosAlmeida, Luís Fernando
Throughout the vehicles industry and electrification, vehicle ride comfort, road holding, and fuel/charge economy have always been important considerations for the design and development of shock absorbers. Vehicle suspension is one of the oscillating power dissipation sources in which the undesired mechanical energy is dissipated into heat waste. Therefore, in this study a regenerative MacPherson strut is modeled and validated to investigate the vehicle vertical dynamics performance as well as the harvestable power that can be used to charge batteries or power vehicle electrical loads. The optimal design parameters of the regenerative MacPherson strut (RE.M.S) is obtained by using multi-object genetic algorithm (MOGA) optimization for a better trade-off between regenerated power, ride comfort, and road holding. The results showed that RE.M.S can function as a semi-active shock absorber as change of duty cycle of charging circuit. Furthermore, the optimal selection of the design
Hegazy, Ahmed H.A.Kaldas, Mina M.Soliman, Aref M.A.Huzayyin, A.S.
As a part of an automobile suspension structure, fatigue durability performance of the automotive stabilizer bar linkage is crucial to the safety and reliability of the suspension system. In this study, the modeling and simulation analysis methods of the stabilizer bar linkage were described in detail, especially for the welded positions between the connecting rod and the spherical shells (or sleeves). Based on the equivalent structural stress method and the theory of critical distances, damage values of welded positions in the stabilizer bar linkage were solved. For the spherical shell end, the simulation reproduced the bench test; and for the sleeve end, the analysis approach was determined by comparing in several different modeling ways. Mooney-Rivlin model was adopted to fit the constitutive relationship of rubber material in the bushing. The above methods were applied to predict the fatigue durability performance of the stabilizer bar linkage product, and the effectiveness was
Wang, XuHan, ChaoDeng, Jianjiao
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, RaffaeleStrano, SalvatoreTerzo, MarioTordela , Ciro
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, ChangshengLiu, XiaoangJia, XingGong, BoXu, Bo
In the fast growing automotive sector, reliability & durability are two terms of utmost importance along with weight and cost optimization. Therefore it is important to explore new technology which has less weight, low manufacturing cost and better strength. It also seek for a quick, cost effective and reliable methodology for its design validation so that any modification can be made by identifying the failures. This paper presents the rig level real world usage pattern simulation methodology to validate and correlate the vehicle level targets for micro strain, wheel forces and displacement on suspension components like optimized Z spring, torque rods, pan hard rod & mounting brackets of newly developed air suspension for buses.
Tangade, Atul BanduBabar, SunilBankar, Milind AchyutraoMehendale, RavindraDhumal, KailasBhusari, DeepakSonawane, RavindraShinde, Saurabh
The parametrized twist beam suspension is a pivotal component in the automotive industry, profoundly influencing the ride comfort and handling characteristics of vehicles. This study presents a novel approach to optimizing twist beam suspension systems by leveraging parametric design principles. By introducing a parameter-driven framework, this research empowers engineers to systematically iterate and fine-tune twist beam designs, ultimately enhancing both ride quality and handling performance. The paper outlines the theoretical foundation of parametrized suspension design, emphasizing its significance in addressing the intricate balance between ride comfort and dynamic stability. Through a comprehensive examination of key suspension parameters, such as twist beam profile, material properties, and attachment points, the study demonstrates the versatility of the parametric approach in tailoring suspension characteristics to meet specific performance objectives. To validate the
Pakala, Pradeep KumarGanesh, Lingadalu
Sports Utility Vehicles (SUVs) Braking performance is a critical parameter, and it is described by the measure of stopping distance & stability of the vehicle at a specified speed. When it comes to electric vehicles, balancing tyre performance parameters like RRc, traction, wear, ride and handling, weight and NVH is challenging due to higher axle weights, higher moment of inertia and high instant torque delivery. This study presents the braking performances of EV-intended tyres at various contact surfaces in both dry & wet conditions. Impact of tyre design attributes like tyre tread pattern, contact patch, tread compound, tyre carcass construction & characteristics studied on 3 different tyres including ultra-high-performance tyres on braking performances. This paper contains the study & analysis of 1) Footprint analysis concerning the shape of the contact patch, pressure distribution, land-sea ratio, and contact area 2)Tyre tread design such as NSD, grooves, ribs & sipes design and
V, PadmasriVellandi, VikramanSundaram, RaghupathiSingh, Ram KrishnanP, PraveenChittibabu, Santhosh
December is a good time to reflect on the past year - to celebrate successes and consider opportunities for improvement - but it is also an opportune time to look to the future. As I think about the year ahead and appraise the tradeshow landscape that'll provide significant content for this magazine, mobilityengineeringtech.com, our e-newsletters and other multimedia products, none is bigger than Bauma in Munich, Germany, particularly in terms of the global construction and mining vehicle industries. The triennial event will cover an area that's equivalent to 86 soccer fields, according to Stefan Rummel, CEO of Messe München GmbH. Speaking to the press during an October virtual preview of Bauma 2025, which takes place from April 7-13, Rummel said that the number of exhibitors - expected to be about 3,600 - will be closer to the 2019 event versus the post-COVID-19 edition that was pushed back from its usual spring timeslot to the fall of 2022.
Gehm, Ryan
This study proposes a multi-mode switching control strategy based on electromagnetic damper suspension (EMDS) to address the different performance requirements of suspension systems on variable road surfaces. The working modes of EMDS are divided into semi-active damping mode and energy harvest mode, and the proposed mode switching threshold is the weighted root mean square value of acceleration. For the semi-active damping mode, a controller based on LQR(Linear Quadratic Regulator) was designed, and a variable resistance circuit was also designed to meet the requirements of the semi-active mode, which optimized the damping effect relative to passive suspension. For the energy harvest mode, an energy harvest circuit was designed to recover vibration energy. In order to reduce the deterioration of suspension performance caused by frequent mode switching in the mode switching strategy, as frequent system switching can lead to system disorder, deterioration of damping effect, and
Zeng, ShengZhang, BangjiTan, BohuanQin, AnLai, JiewenWang, Shichen
Air suspension systems are increasingly in demand in high-end cars due to their ability to vary ride height based on vehicle loads, road conditions, and speeds. This trend has driven manufacturers to enhance the performance of these systems. Predicting and optimizing the performance of the air spring system for various vehicle loads and conditions has become essential. The performance of an air suspension system is typically measured by its ability to suspend the vehicle within a specified target time. Therefore, it is necessary to model the air spring system—including the air spring, compressor, pneumatic lines, and valves—and integrate it with the vehicle. This modeling helps in predicting performance and optimizing the system. Additionally, a validated system model enables other important calculations, such as sizing the valves, pneumatic hoses, and compressors. In this study, a complete air spring system model has been developed alongside a 15-degrees-of-freedom car chassis to
Ahmed, Saad AnwarHupfeld, JanRajput, Brijesh
In order to modify both stiffness and damping rates according to various road conditions, this research introduces a pneumatic spring in conjunction with a magnetorheological (MR) fluid damper as a single suspension unit for each wheel in the truck. Preventing weight transfer and improving riding comfort during braking, acceleration, and trajectory prediction are the main objectives. A two-axle truck has been used, consisting of three degrees of freedom for the sprung mass, including vertical, pitch, and roll motions, and four degrees of freedom for the unsprung masses, which have been redesigned according to the different types of springs and dampers. Pneumatic-controlled springs, often referred to as dynamic or classic models, replace laminated leaf springs commonly found in vehicles. Additionally, an MR damper replaces a hydraulic double-acting telescopic shock absorber. These models are studied to evaluate the effect of pneumatic spring parameters on truck dynamics. Pneumatic
Shehata Gad, AhmedEl-Zomor, Haytham M.
Elastomeric bushings are common components in vehicles, used to reduce noise, vibration, and harshness. Rubber bushings are employed in suspension components such as control arm bushings, subframe bushings, and motor mount bushings, each with varying static and dynamic stiffness requirements depending on vehicle weight and ride and handling performance. Traditional rubber bush simulations typically use simple material models like hyperelastic or viscoelastic models. However, recent advancements have introduced more sophisticated material models to capture the nonlinear and time-dependent behavior of rubber materials. These advanced models may incorporate nonlinear viscoelasticity, strain rate dependency, and damage mechanics. Rubber bushings experience multiple physical phenomena simultaneously, such as mechanical loading, thermal effects, and fluid-structure interaction. New simulation techniques enable the coupling of different physics domains, allowing for a comprehensive analysis
Hazra, SandipMore, VishwasTangadpalliwar, Sonali
With the advent of electric and hybrid drivetrain in the commercial vehicle industry, electrically driven reciprocating compressors have gained widespread prominence. This compressor provides compressed air for key vehicle systems such as brakes, suspension systems and other auxiliary applications. To be a market leader, such an E-compressor needs to meet a myriad of design requirements. This includes meeting the performance by supplying air at required pressure and flow rate, durability requirements and having a compact design while maintaining cost competitiveness. The reed valve in such a compressor is a vital component, whose design is critical to meet the aforementioned requirements. The reed valves design has several key parameters such as the stiffness, natural frequency, equivalent mass, and lift distance which must be optimized. This reed valve also needs to open and close rapidly in response to the compressor operating speed. Since it is the order of milliseconds, the valve
J, BharadwajT, SukumarPendyala, Vamsi KrishnaPaul Pandian, Adheenthran
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, LeiLi, TaoYang, Guixing
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