Half-vehicle Suspension Research Articles

Utilizing Hybrid Machine Learning Framework for Half-Vehicle Suspension Control to Minimize Road-Induced Vibrations

Utilizing Hybrid Machine Learning Framework for Half-Vehicle Suspension Control to Minimize Road-Induced Vibrations

Modeling and Simulation of Active Half-vehicle Suspension Based on a New Output-feedback H∞ Controller

Modeling and Simulation of Active Half-vehicle Suspension Based on a New Output-feedback H∞ Controller

Multi-Strategy Advanced Snake Optimizer-Based Optimal Feedback Control of Half Vehicle Suspension

Multi-Strategy Advanced Snake Optimizer-Based Optimal Feedback Control of Half Vehicle Suspension

Experimental and Numerical Study of Shock Absorber Characterization and The Implication on The Dynamics of Half Vehicle Suspension System Model

This study aimed to characterized shock absorber damping for passenger comfort. The riding comfort of the vehicle has direct correlation to the damping characteristic of the shock absorber of the suspension system. Two different shock absorbers were experimentally evaluated, and their damping characteristics were integrated into a half-car model to study the vehicle's dynamic response to harmonic road disturbances. The investigation involved numerical simulations of the half-car model subjected to harmonic road disturbances, represented by a set of ordinary differential equations solved using the Dormand-Prince method. Experimental data yielded average damping forces of 502.77 N for shock-absorber #1 and 192.03 N for shock-absorber #2. Calculations resulted in damping coefficients of 3888.57 N·s/m for shock-absorber #1 and 1397.85 N·s/m for shock-absorber #2, with corresponding damping ratios of 0.29 and 0.105. These damping ratios generally aligned with typical values for passenger car shock absorbers, except for shock-absorber #2, which deviated from the expected range. The study found that at 60 km/h and 90 km/h, shock-absorber #1 with ζ=0.29 exhibited superior performance in reducing displacement amplitude compared to shock-absorber #2 at ζ=0.105. However, at 120 km/h, both shock-absorbers displayed similar responses, with shock-absorber #1 slightly surpassing shock-absorber #2 in displacement amplitude.

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.

Determination of optimal battery locations for ride comfort in electric automobiles using a nonlinear half-vehicle suspension model

Batarya elektrikli araçların ağırlığına katkıda bulunan en büyük kalemlerden biridir ve konumu süspansiyon sisteminin performansını doğrudan etkilemektedir. Bu makalenin amacı tekerlek içi motorlu elektrikli otomobillerde sürüş konforu açısından optimal batarya konumlarının lineer olmayan bir taşıt süspansiyon modeli kullanılarak belirlenmesidir. Analizlerde tüm yay ve amortisörlerin lineer karakteristiklerine ilaveten kübik doğrusalsızlıklarının da hesaba katıldığı yedi serbestlik dereceli bir yarım taşıt süspansiyon modeli kullanılmıştır. Modelde yay ve amortisör doğrusalsızlıklarına ek olarak tüm trigonometrik doğrusalsızlıklar da dikkate alınmıştır. Sinüzoidal formda 48 farklı yol profili ve 3 farklı ilerleme hızı ile toplamda 144 farklı sürüş senaryosu oluşturulmuş ve her bir senaryo için aracın boylamasına ekseni boyunca 36 batarya konumu test edilerek optimal olanı bulunmuştur. Optimizasyon kriteri, sürücü ve koltuğunun dikey ivmesinin kök ortalama kare değerinin minimizasyonudur. Gerçekleştirilen 5184 analiz neticesinde optimal batarya konumunun 0,2 ila 5 m arasındaki dalga boylarına sahip yol profilleri için aracın orta kısmı; 10 ila 30 m arasındaki dalga boylarına sahip yol profilleri içinse aracın arka kısmı olduğu görülmüştür.

Effect of delayed resonator on the vibration reduction performance of vehicle active seat suspension

The combination of dynamic vibration absorber and partial state feedback with time-delay is called delayed resonator. In order to suppress the seat vibration caused by uneven road surface and improve ride comfort, the delayed resonator is applied to the seat suspension to realize active control of the seat suspension system. The dynamic model of the half-vehicle suspension system is established, and the time-delay differential equation of the system under external excitation is solved by the precise integration method. The root mean square of the time-domain vibration response of seat displacement, seat acceleration and vehicle acceleration are selected as the objective function. Then, the optimal time-delay control parameters are obtained by particle swarm optimization algorithm. The frequency sweeping method is used to obtain the critical time-delay value and time-delay stable interval of the system. Finally, an active seat suspension model with delayed resonator is established for numerical simulation. The results show that the delayed resonator can greatly suppress the seat vibration response regardless of the road simple harmonic excitation or random excitation. Compared with dynamic vibration absorber, it has a better vibration absorption effect and a wider vibration reduction frequency band.

A comprehensive comparison of the vehicle vibration energy harvesting abilities of the regenerative shock absorbers predicted by the quarter, half and full vehicle suspension system models

Regenerative shock absorber has been studied intensively for generating electricity from motion energy that would have been otherwise dissipated and wasted in the form of heat. Integration of the regenerative shock absorber with the vehicle suspension system can incorporate the interaction between the wheels and vehicle body, resulting in more accurate power output results. This paper presents the modellings of quarter, half and full vehicle suspension system models integrated with regenerative shock absorbers based on the same baseline vehicle. The time domain and frequency domain analyses enable a comprehensive comparison of all three suspension system models to be conducted in terms of the effects of vehicle speeds, position of vehicle center of gravity, road classifications (road class A, C and E) and driving speed cycles. The results suggest that the shift of vehicle center of gravity position does not affect the results of any suspension system models. All three suspension system models can respond well to road classification change and rougher road can yield higher power output. The quarter vehicle suspension system model does not present accurate power output results in the low frequency range. Moreover, it also behaves poorly with the vehicle speed variation, which limits its use to Highway Fuel Economy Test Driving Cycle. The half vehicle suspension system model resembles full vehicle suspension system model really well regardless of frequency range, vehicle speed variations and road classifications, when the transverse road profile is neglected.

The double-delay reducing vibration control for five-degree-of-freedom half-vehicle model in idle condition

When running in idle condition, the vehicle has no speeds and road excitation, and the engine vertical self-vibration is the main excitation source. In this paper, a five-degree-of-freedom half-vehicle suspension model with double-delay feedback control is proposed to improve the vibration performance in idle condition. First, according to the system amplitude–frequency characteristic, the multiobjective function combining the vehicle body acceleration and pitching angular acceleration is established. Then, utilizing particle swarm optimization in optimizing and analyzing, the optimal feedback gains and time delays of the suspension system are obtained. Subsequently, a new frequency scanning method is utilized to analyze the stability of the controlled suspension system with the optimal feedback parameters. Finally, numerical simulations in the Matlab/Simulink environment are conducted to validate the performance of time-delay reducing vibration control on different engine feedback condition. Simulation results indicate that the active suspension with time-delay feedback control based on engine acceleration has better reducing vibration performance, and the root mean square of vehicle body and pitching angular acceleration are, respectively, reduced 87.37 and 80.01% than that without time delay. The research on vehicle suspension system with time-delay feedback control can improve the vibration performance effectively compared to the conventional one.

Parameter study and optimization of a half-vehicle suspension system model integrated with an arm-teeth regenerative shock absorber using Taguchi method

Abstract This paper presents a novel regenerative shock absorber that utilizes an arm-teeth mechanism to convert linear to rotational motion and to amplify the generator input speed. The flywheel of the arm-teeth mechanism also acts as an energy-storing element, allowing for smooth operation especially on a rough and uneven road surface. The critical parameters are identified through experiments and the simulation model is established based on a half-vehicle suspension system model. The novelty of this work is the proposed arm-teeth mechanism and the optimization of the half-vehicle suspension system through the Taguchi method. In this method, the ratio of the peak output power over the squared excitation displacement amplitude and the frequency bandwidth of the front and rear shock absorbers are set as targets and evaluated respectively. The effects of each parameter on the targets and the optimal parameter combinations are identified through the Taguchi matrix calculations. The optimized system is evaluated under the excitation of the road surface profiles of Class A, C and E of ISO 8606. It is found that the optimized system is able to harvest more energy with a broader frequency bandwidth than the original system at a certain speed for all three random road profile classifications.

PSO-Fuzzy Gain Scheduling of PID Controllers for a Nonlinear Half-Vehicle Suspension System

PSO-Fuzzy Gain Scheduling of PID Controllers for a Nonlinear Half-Vehicle Suspension System

Optimized Fractional-Order Proportional Integral Derivative Controller for Active Vehicle Suspension System Performance Enhancement

In this paper, an optimal Fractional Order Proportional Integral Derivative (FOPID) controller is applied in vehicle active suspension system to improve the ride comfort and vehicle stability without consideration of the actuator. The optimal values of the five gains of FOPID controller to minimize the objective function are tuned using a Multi-Objective Genetic Algorithm (MOGA). A half vehicle suspension system is modelled mathematically as 6 degrees-of-freedom mechanical system and then simulated using Matlab/Simulink software. The performance of the active suspension with FOPID controller is compared with passive suspension system under bump road excitation to show the efficiency of the proposed controller. The simulation results show that the active suspension system using the FOPID controller can offer a significant enhancement of ride comfort and vehicle stability.

Dynamic output-feedback H ∞ control for active half-vehicle suspension systems with time-varying input delay

This paper addresses the new output-feedback H ∞ control problem for active half-vehicle suspension systems with time-varying input delay. By introducing multi-objective synthesis, a new dynamic output-feedback H ∞ controller is designed such that the closed-loop suspension system is asymptotically stable with guaranteed robust performance in the H ∞ sense. The proposed controller is formulated in terms of linear matrix inequality (LMI) based on the auxiliary function-based integral inequality method and the reciprocally convex approach. A new delay-dependent sufficient condition for the desired controller offers a wider range of control input delay. Numerical examples are provided to validate the effectiveness of the proposed design method.

SUSPENSION OPTIMIZATION USING DESIGN OF EXPERIMENT (DOE) METHOD ON MSC/ADAMS-INSIGHT

In this paper, the optimum setting for suspension hard points was determined from a half vehicle suspension system. These optimized values were obtained by considering the Kinematic and Compliance (K&C) effects of a verified PROTON WRM 44 P0-34 suspension model developed using MSC/ADAMS/CAR. For optimization process, multi body dynamic software, MSC/ADAMS/INSIGHT and Design of Experiment (DoE) method was employed. There were total of 60 hard points (factors) in x, y and z axis-direction for both front and rear suspension while toe, camber and caster change were selected as the objective function (responses) to be minimized. The values of 5 mm, 10 mm and 15 mm were used as relative values of factor setting to determine the factor range during optimization process. The hard point axis-direction that has the most effects on the responses was identified using the Pareto chart to optimize while the rests were eliminated. As expected result, a new set of suspension system model with a selected of Kinematic and Compliance (K&C) data set were obtained, and compared with the verified simulation data when subjected to the vertical parallel movement simulation test to determine the best setting and optimum suspension hard points configuration.

Robust quantised control for active suspension systems

This study investigates the robust quantised H∞ control problem for active suspension systems. First, based on the half-vehicle suspension model, the dynamical system with polytopic parameter uncertainties, which are caused by vehicle load variation, is established. In the meanwhile, the active suspension system performance, namely ride comfort, road holding and suspension deflection, are taken into account for the control design aim. Secondly, an input delay approach is utilised to transform the resulting active vehicle suspension system with sampling and quantisation measurements into a continuous-time system with a delay in the input sector bound uncertainty. Thirdly, robust quantised H∞ performance analysis and controller synthesis criteria are presented in the form of convex optimisation problem by exploiting the Lyapunov functional approach. The existing robust quantised H∞ controller condition not only guarantees the robust asymptotical stability of the closed-loop system, but also satisfies the output constrained performance. Finally, the effectiveness and application of the proposed method can be demonstrated by providing a design example.

Modeling and control of a nonlinear half-vehicle suspension system: a hybrid fuzzy logic approach

Modeling and control of vehicle suspension system are high noteworthy from safety to comfort. In this paper, an analytical nonlinear half-vehicle model which is included quadratic tire stiffness, cubic suspension stiffness, and coulomb friction is derived based on fundamental physics. A hybrid fuzzy logic approach which combines fuzzy logic and PID controllers is designed for reducing the vibration levels of passenger seat and vehicle body. Performances of designed controllers have been evaluated by numerical simulations. Comparisons with classical PID control, Fuzzy Logic Control (FLC) and Hybrid Fuzzy-PID control (HFPID) have also been provided. Results of numerical simulations are evaluated in terms of time histories of displacement and acceleration responses and ride index comparison. A good performance for the Hybrid Fuzzy-PID controller with coupled rules (HFPIDCR) is achieved in simulation studies despite the nonlinearities.

A HIL simulation experiment design based on a hierarchical modelling method

Due to a hierarchical modelling method that a half vehicle suspension could be considered as a combination of two parallel quarter suspensions, the experiment proposed not only displayed the controllability of a quarter vehicle suspension but also evaluated damping capacity of a half suspension according to equations of centre level. The semi-active control of a half vehicle suspension was executed by computer software equipped with some facilities such as a vibration table, a magneto-rheological damper and transducers, etc. The real time quadric Linear Quadratic Gaussian (LQG) control strategies were adopted by the front and rear quarter suspensions, respectively. The results verify the validity and practicability of the experiment designed in the paper.