Suspension Performance Research Articles

Design and experimental analysis of magneto-rheological damper featuring a labyrinthic dual-channel valve

For the sake of improving the damping performance of the cab suspension system, the MR damper featuring the labyrinthic dual-channel valve (LDCV-MRD for short) is proposed in this paper, which is composed of a mixture of circular channel, circular disk channel and circular tube channel. The LDCV-MRD is designed structurally and the magnetic circuit is analyzed. The output damping force mathematical model is established, and the coil’s number of turns is computed. The magnetic field in the damping channel of LDCV-MRD is simulated and analyzed. The processed and fabricated LDCV-MRD is tested, and the experimental results are compared and analyzed with the simulation results. The results show that the simulated values of the maximum damping force and the adjustable coefficient fit well with the experimental results. The peak output damping force of the experiment achieves 21 008 N. The adjustable coefficient reaches about 5.61, when the input current gets to 2 A.

Event‐triggered based finite‐frequency control for vehicle electrohydraulic suspension with force tracking

AbstractThis study investigates the problem of event‐triggered based finite‐frequency control for vehicle electrohydraulic suspensions with force tracking. A novel hierarchical control methodology is proposed by designing event‐triggered finite frequency and active force tracking controllers to improve the suspension performance. In practical application, active suspension system can be constructed as the network control system under consideration of the electrohydraulic actuator's nonlinear dynamics and parametric uncertainties, and in‐vehicle network delay in a unified framework. Then, due to the more sensitiveness of the human body to vertical vibrations in 4–8 Hz and limited in‐vehicle network communication resource, an event‐triggered finite frequency controller is developed based on the generalized KYP lemma and Lyapunov stability theory. The triggered condition is designed for the network control system with in‐vehicle network delay. Other physical constraints including suspension working space, tire dynamic load and actuator saturation are also introduced in this controller design. It can generate the target force to satisfy suspension performance requirements under each triggered instant period. Furthermore, since the nonlinearity and uncertainty always exist in the electrohydraulic actuator, a filter‐based adaptive sliding mode control method is employed to design the active force tracking controller. It can precisely drive electrohydraulic actuator to track the target constant force generated by event‐triggered finite frequency controller. Finally, the results validate the effectiveness and saving communication resource capability of the proposed control methodology.

Active suspension for all-terrain vehicle with intelligent control using artificial neural networks

The automotive industry focuses on developing advanced protection and stability control systems, particularly for suspension and steering, to enhance vehicle comfort, luxury, and safety. This research presents an intelligent controller for all-terrain vehicle (ATV) suspension systems based on Artificial Neural Network (ANN) technology. The controller leverages ANN capabilities to optimize system performance. MATLAB simulations were conducted to evaluate its effectiveness under various disturbances. A comparative analysis compared the ANN regulator, classic ANFIS regulator, and passive performance in different disturbance scenarios. The simulation results demonstrate exceptional performance of the ANN-based controller in displacement reduction, speed, acceleration, and robustness. The controller effectively mitigates disturbances, enhancing overall suspension system performance. These findings highlight the advantages of employing ANN technology in ATV suspensions. This research contributes to intelligent control systems advancement in the automotive industry, specifically in ATV suspensions. The demonstrated improvements have the potential to enhance passenger comfort, vehicle stability, and safety across terrains. By implementing ANN-based controllers, automotive manufacturers can optimize suspension systems, leading to improved vehicle performance. Several indicators, including RMSE, MRE, and R2, were utilized to test and validate the models. The R2 values for the three quality parameters ranged from 0.989 to 0.999, indicating a high level of consistency in the predictions made by the ANN, a "5-12-1" structure is employed. The results of this study add to the expanding body of knowledge endorsing the efficacy of ANNs in simulating and optimizing quarter-vehicle dynamics.

Performance improvement study of nonlinear bionic suspension based on inerter and on–off control strategy

How to improve the dynamic performance of nonlinear suspension systems is a focus of attention. The combination of inerter and on–off control strategy can effectively improve the dynamic performance of linear suspension systems, but it will also bring some adverse effects. This paper puts forward a nonlinear suspension system performance enhancement scheme based on semi-active on–off control strategies of inerter to eliminate the adverse effects of the introduction of the inerter and to enhance the dynamic performance of nonlinear suspension systems. This paper takes the nonlinear double-diamond bionic kangaroo leg suspension system as an example and adopts the above scheme to carry out dynamic modeling, time–frequency domain dynamic characteristics analysis, and control characteristics research. The results show that the dynamic performance of the proposed nonlinear suspension system with passive inerter is partially better than that of the original suspension system in time–frequency domain, while the overall dynamic performance of the proposed nonlinear suspension system with semi-active inerter is better than that of the original suspension system. The proposed nonlinear suspension system with semi-active inerter shows good stability and adaptability under different working conditions, and the proposed control strategies can eliminate the adverse effects of passive inerter. The above results indicate the correctness of the proposed scheme and the effectiveness of the control strategies.

Determination of Coal Spontaneous Combustion Zone in Overlaying Multilayer Goaf and Its Control Technology of Thickened Slurry

ABSTRACT In order to study the law of coal spontaneous combustion and prevention methods in the overlying multilayer goaf, this study combined the situation of 378 working face and overlying multilayer goaf in Anyuan Coal Mine and determined the coal spontaneous combustion zone in the overlying multilayer goaf by overlaying the oxidation zones divided by wind velocity and oxygen concentration, and verified it. Subsequently, a new type of thickened slurry was prepared based on sodium alginate, carboxymethyl cellulose, loess, and water as the main raw materials, and a thickened slurry fire prevention technique suitable for overlying multilayer goaf was proposed. The research results indicated that the coal spontaneous combustion zone was located near the 3117 return air roadway and the 378 return air roadway in 378 working face, as well as the upper part of 3117 return air roadway in 372 (4) goaf. When the water-soil ratio was 8:1 and thickener concentration was 0.3%, the suspension performance of the thickened slurry was better. At this point, the corresponding yield stress was the smallest and the flow ability was better. Through the used of fixed-point grouting and regional sealing of a thickened slurry fire prevention technique, it was found that the CO concentration gradually decreased to zero in the 372 (4) goaf. The oxygen concentration significantly decreased and the pressure difference remained stable in the sealing wall in the return air roadway. The outlet water temperature were below 25°C all boreholes.

Probing the roles of surface characteristic of suspended nanoparticle in shear thickening suspensions

The surface characteristic of suspended nanoparticle is an extremely important property for the non-Newtonian behavior of shear thickening suspensions. Easy access to distinct surface characteristics and a deep understanding of the role of friction and adhesion forces remains challenging yet critical to study the suspension performance. In this work, by synthesizing mesoporous silica with different surface roughness and groups, the influence of surface characteristics on the non-Newtonian behavior of suspension is comprehensively explored. The results show that the suspensions containing particles with rough surface and hydroxyl groups on the surface have higher shear thickening power, lower critical shear rate, lower discontinuous shear thickening transition fraction and lower jamming fraction. Furthermore, the test of the first normal stress difference N1 shows that the interparticle friction and adhesion both reduce the critical volume fraction of the transition from fluid lubrication dominance to frictional contact dominance in the suspension. This finding deepens the understanding of phase transformation mechanism, and open an approach to accelerate the advanced shear thickening suspensions design for next-generation intelligent materials.

Loofah sponge crosslinked polyethyleneimine loaded with biochar biofilm reactor for ecological remediation of oligotrophic water: Mechanism, performance, and functional characterization

The removal of complex pollutants from oligotrophic water is an important challenge for researchers. In this study, the HCl-modified loofah sponge crosslinked polyethyleneimine loaded with biochar (LS/PEI@biochar) biofilm reactor was adapted to achieve efficient removal of complex pollutants in oligotrophic water. On the 35 d, the average removal efficiency of chemical oxygen demand (COD), ammonia nitrogen (NH4+-N), calcium (Ca2+), and phosphate (PO43--P) in water was 51, 95, 81, and 77 %, respectively. Additionally, it effectively used a low molecular weight carbon source. Scanning electron microscopy (SEM) results showed that the LS/PEI@biochar biocarrier had superior biofilm suspension performance. Meanwhile, analysis of the biocrystals confirmed Ca2+ and PO43- removal through the generation of CaCO3 (calcite and vaterite) and Ca5(PO4)3OH. This study demonstrated that the system has great efficiency and application prospect in treating oligotrophic water on the laboratory scale, and will be further validated for practical application on large-scale oligotrophic water.

Research on Inertial Force Attenuation Structure and Semi-Active Control of Regenerative Suspension

To improve the energy recovery ability of the energy-regenerative suspension, a transmission is generally used to increase the motor speed, but this results in a significant increase in the equivalent inertial mass of the suspension. The research on energy-regenerative suspension has been ongoing for more than 20 years, but there have been few product applications, mainly due to the failure to solve the problem of the deterioration of suspension performance caused by equivalent inertial mass. This paper proposes a new suspension configuration with the suspension shock absorber connected to a high-frequency vibration reduction structure and establishes a vibration transmission model. Through frequency domain analysis, it has been conclusively proven that the new-configuration can significantly reduce both the sprung mass acceleration and relative dynamic load of the energy regenerative suspension. On the basis of frequency domain analysis, a scheme based on PWM control of the dissipation resistance value of the energy regenerative suspension is proposed, and through bench comparison experiments, it has been verified that the new-configuration suspension can eliminate the oscillation of the damping force curve of the shock absorber and significantly improve the suspension performance. Further experiments show that using the skyhook semi-active control algorithm the new-configuration suspension can further reduce the sprung mass acceleration and relative dynamic load.

Performance enhancements of semi-active vehicle air ISD suspension

To explore an innovative approach for enhancing the vibration isolation performance of vehicle air suspension systems, this study introduces the inerter element into the vehicle air suspension and investigates the dynamic behavior of the semi-active vehicle air ISD (inerter-spring-damper) suspension. Initially, a dynamic model of the quarter semi-active vehicle air ISD suspension is established, followed by conducting multi-objective optimization of the core parameters using the genetic algorithm. Subsequently, the dynamic performance of the semi-active vehicle air ISD suspension is thoroughly examined through simulations and analyses in both the time and frequency domains. The results demonstrate notable improvements in various aspects: the root-mean-square (RMS) value of the vehicle body acceleration in the semi-active vehicle air ISD suspension is reduced by 12.8%, the RMS value of the suspension working space is decreased by 37.3%, and the RMS value of the dynamic tire load experiences an 8.9% reduction. The findings of this paper indicate that the proposed semi-active vehicle air ISD suspension outperforms both the passive vehicle air suspension and the semi-active vehicle air suspension without an inerter, significantly enhancing the vehicle’s ride comfort, handling stability, and driving safety.

Performance analysis of vehicle magnetorheological semi-active air suspension based on S-QFSMC control

The performance of the suspension is a crucial criterion for evaluating both vehicle handling and passenger comfort. To enhance suspension performance, this study proposes the design of a Quantum Genetic Fuzzy Sliding Mode Controller (S-QFSMC) based on the Smith predictor estimator, building upon the foundation of the vehicle magneto-rheological semi-active air suspension. According to the physical model of the vehicle suspension, a mechanical model of a quarter-vehicle magneto-rheological semi-active air suspension with time delay is established. On this basis, a conventional sliding mode controller is designed, and quantum genetic algorithm and fuzzy control principles are employed to optimize the chattering issue associated with sliding mode control. The Smith predictor estimator is utilized to effectively compensate for the time delay in the suspension system. Subsequently, a simulation analysis of the vehicle suspension performance is conducted. The results indicate that, compared to passive suspension control, both the QFSMC controller and the S-QFSMC controller improve the suspension performance, with the S-QFSMC controller exhibiting superior comprehensive improvement. This validates the effectiveness of the designed controllers.

Optimization Design of Double Wishbone Front Suspension Parameters for Large Mining Dump Truck and Analysis of Ride Comfort

With the advancement of technology, mining trucks are gradually becoming larger, imposing higher performance requirements on the front suspension. There is a need to transform the original integral non-independent front axle of mining dump trucks with a payload exceeding 300 tons into an independent front suspension with a double-wishbone suspension. The changing of the front suspension is bound to have an impact on the overall vehicle’s handling stability and ride comfort. Therefore, the following research is conducted to investigate and analyze these effects. Firstly, the paper proposes a method for optimizing the parameters of the double-wishbone front suspension. The double-wishbone front suspension is modeled, and a comparison with a kinematic model is conducted to validate the accuracy of the model. Secondly, unreasonable hardpoint parameters are optimized. Thirdly, a dynamic model of the entire vehicle is established based on the optimized parameters, and an analysis of handling stability and ride comfort for the entire vehicle is performed. Finally, simulation results are compared and analyzed against experimental data. The results indicate that the optimized positioning parameters not only effectively enhance the suspension performance of the mining dump truck but also meet the requirements for handling stability and smoothness. The overall smoothness of the vehicle is significantly improved after the modification. This study not only holds significant engineering value in reducing vibrations in dump trucks and enhancing driver comfort, but also provides theoretical support for subsequent research and development in the industry.

Influence of structural properties on the suspension performance of ultra-high temperature stabilizers

One of the key challenges preventing the exploration and development of ultra-deep oil and gas deposits is the settlement instability of cement slurry at extremely high temperatures. In the previous work, an ultra-high temperature suspension stabilizer was created to enhance the cement slurry's high temperature settlement stability. This work investigates its mechanism from the standpoint of structural characteristics based on the prior research. Thermal stability tests and calculations of the pyrolysis activation energy were used to examine the structural features of the suspension stabilizer. The viscosity-temperature relationship, the microstructure of the suspension stabilizer solution, the molecular structure change of the suspension stabilizer in the solution environment, and the interaction energy with water molecules were all studied in conjunction with contemporary material testing techniques and molecular dynamics simulation calculations. The findings indicate that: 1) The bulk structure of the suspension stabilizer has a pyrolysis temperature of 330 °C, which indicates a degree of heat resistance; 2) In a solution environment, the viscosity of the solution is a critical factor in determining the stability of the cement slurry's sedimentation, which is dependent on the integrity of the amide group in the suspension stabilizer. The cyclic functional group's ortho action prevents the amide monomer from hydrolyzing in the ultra-high temperature suspension stabilizer. The cement slurry has good sedimentation stability because the hydrogen link between the retained amide group and the water molecule has not entirely broken down, and the solution still has some viscosity.

An Improved Mathematical Model for Speed Sensorless Control of Fixed Pole Bearingless Induction Motor

In a fixed pole bearingless induction motor (FPBIM), the influence of the suspension winding is neglected in the traditional mathematical model, leading to the inaccurate speed estimation of speed sensorless control. Aiming at this problem, this paper proposes an improved mathematical model. First, considering the influence of the suspension winding, the resistance matrix and inductance matrix are extended based on the traditional natural coordinate model and the FPBIM's natural coordinate model (in the <italic xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">a-b-c</i> stationary frame) is established. Secondly, through the rotation transformation by an extended transformation matrix, the FPBIM's two-phase stationary coordinate model (in the α-β stationary frame) is obtained and the flux linkage equations are extracted from it. Finally, to verify the effectiveness and feasibility of this improved mathematical model, it is applied to the speed sensorless control based on model reference adaptive system (MRAS). The simulations and experiments show that the FPBIM improved mathematical model gets more accurate speed estimation and better rotation performance under no-load, load, load disturbance and displacement disturbance, while the suspension performance is not affected.

A nonlinear model predictive control for air suspension in hub motor electric vehicle

The hub-motor electric vehicle (HM-EV) is considered as an ideal configuration for electric vehicles (EVs). However, the electromechanical coupling effect deteriorates HM-EV ride comfort, which limits its widespread application in EVs. In this study, the HM-EV dynamic system with air springs is proposed to intervene in vehicle attitude and ride comfort. The HM-EV dynamic model with air spring, considering the electromechanical coupling effect, is established and the test validation is investigated. Then quasi-infinite horizon nonlinear model predictive control (QIH NMPC) is designed to improve the longitudinal and vertical dynamic performance. The dynamic performance of passive suspension, air suspension based on QIH NMPC, air suspension based on MPC, and PID control receptively, are compared under several random road scenarios. Finally, the results indicated that the proposed control algorithm can improve ride comfort, reduce motor vibration, and improve longitudinal and vertical dynamic performance.

Investigation of a semi-active suspension system for high-speed trains based on magnetorheological isolator with negative stiffness characteristics

As the operation speed of high-speed train increases, trains with fixed suspension stiffness will encounter dramatical vibrations, especially when its lateral resonance occurs. This greatly affects the ride comfort and safety of the trains. Based on this motivation, a novel stiffness variable suspension system using magnetorheological elastomer (MRE) isolator with negative stiffness is proposed. The controllable stiffness can make the train avoid lateral resonance while the negative stiffness characteristics can provide an actuating force similar to the active control, which further improve the vibration attenuation performance of the suspension. The new MRE isolator was firstly fabricated and tested to verify its stiffness variability, especially negative stiffness characteristics. Four different suspension systems were then tested on a 6-DOF vibration platform for the performance comparison. The experimental results show that this new semi-active lateral suspension system has improved vibration attenuation performance than the passive system and the traditional MRE isolation system without negative stiffness. The vibration attenuation performance of the new suspension system is even comparable to that of some of the existing active suspensions while avoiding the disadvantages of the active control.

Improvement of vibration isolation performance of multi-mode control seat suspension system through road recognition using wavelet-LSTM approach

Improvement of vibration isolation performance of multi-mode control seat suspension system through road recognition using wavelet-LSTM approach

Research on the Vibration Reduction Performance of Swing Cylinder Type Hydro-pneumatic Suspension for Tracked Vehicles

Research on the Vibration Reduction Performance of Swing Cylinder Type Hydro-pneumatic Suspension for Tracked Vehicles

Оценка работоспособности магнитных индикаторов при магнитопорошковом контроле деталей подвижного состава железных дорог

Purpose: To evaluate the performance of various luminescent magnetic suspensions on the example of individual small-sized parts of railway transport, differing in geometric shape, color, surface roughness and the presence of paint coating. To show the need to test magnetic suspensions, including ready-made ones, in aerosol cans on tuning (control) samples, taking into account the color, the presence of a non-magnetic coating, and other characteristics. Methods: Comparison of the obtained magnetic powder indications during wet magnetic powder control under conditions of magnetization of rolling stock parts by the applied field method using the MD-12PSH flaw detector. In practice, identical conditions have been maintained for magnetizing components at the center of the solenoid, uniformly applying magnetic suspension through aerosol can and sprayer to the surface, as well as inspecting for the presence of accumulations of magnetic powder particles under both daylight and ultraviolet irradiation. Results: The experiment has shown that the technical characteristics of the magnetic indicator stated in the passport by the manufacturer shouldn’t be fully trusted and relied on. At the same time, the use of one or more standard or tuning (control) samples with a huge range of control objects is not enough. Practice shows that, taking into account the fact that surfaces of parts differ, it is necessary to conduct a comparative analysis of magnetic suspensions for the brightness of powder glow, contrast, measured length of the magnetic indication on parts with artificial or natural defects with exactly the same surface. Practical significance: The article shows that it is necessary to use for each control object its own tuning or control sample. Only those objects of control that are identical or comparable in size, shape, color, roughness, and other characteristics fall under the exception. Therefore, only one sample can be used for them.

Synthesis, characterization and application of a magnetic nanoencapsulated PCM in enhancing the natural convection in a cube cavity

Encapsulation of phase change materials (PCMs) is an intelligently effective way to overcome the challenges of PCMs usage in heat storage and transfer applications. At the first stage of the current study, a novel magnetic nanoencapsulated PCM (M−NEnPCM) consisting of n-Octadecane (n-C18) coated with a poly methyl methacrylate (PMMA) shell was synthesized through the miniemulsion ultrasonic-assistant polymerization technique. The magnetic property was introduced to the nanocapsules by adding surface-modified Fe3O4 nanoparticles into the core during the formation step. The dynamic light scattering (DLS) results showed an average nanocapsule size of 78 nm. The scanning electron microscope (SEM) along with transmission electron microscope (TEM) images confirmed the spherical shape with a core/shell structure of the M−NEnPCM. According to the differential scanning calorimetry (DSC), M−NEnPCM had melting and crystallization latent heats of 116.47 and 124.71 J/g, respectively. Moreover, based on vibrating sample magnetometry (VSM) results, the superparamagnetic property of M−NEnPCM is proved. At the second stage, the performance of water suspensions containing different amounts of the as-prepared nanocapsules in enhancing the natural convection in a cube cavity was investigated under various heat fluxes and magnetic field flux densities. The results illustrated that the use of nanocapsules leads to enhance the natural convection up to 2 times higher than that of pure water; while there are optimum levels of M−NEnPCM concentration and magnetic field flux density at which the heat transfer coefficient is maximized.

A new energy-feeding variable damping control strategy for electromagnetic hybrid suspension systems

Traditional energy-feeding suspensions exhibit a non-adjustable damping characteristic during energy recovery, which can compromise the dynamic performance of the suspension system. To overcome this issue, this paper proposes an energy-feeding variable damping control strategy (EFVD) predicated on an electromagnetic hybrid suspension system. This strategy aims to achieve adjustable damping during energy recovery, reducing energy losses while ensuring optimal suspension performance. Building on a half-vehicle suspension model, we construct a dynamic model of the electromagnetic hybrid suspension. By leveraging an enhanced hybrid-skyhook and ground-hook control algorithm (HSGH), we solve for the target control force. We then design a force distribution controller based on the EFVD strategy, aiming to optimize suspension dynamic performance and energy feeding efficiency. And we conduct a simulation study, measuring power supply efficiency and suspension dynamic performance as key evaluation metrics. The results demonstrate the superiority of the proposed EFVD strategy over conventional passive and active suspension control strategies, highlighting its effectiveness and reliability in maintaining dynamic performance while enhancing energy efficiency. This underscores the potential of the EFVD strategy as a practical solution for future suspension system design and energy management.