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According to the principle of acoustic black hole effect, a badminton racket design method of embedded one-dimensional acoustic black hole structure was proposed. Based on the finite element simulation analysis, the broadband vibration attenuation characteristics of one-dimensional acoustic black hole structure were studied. The results show that this structure can not only ensure the light quality of the system, but also achieve good vibration reduction effect. In the absence of damping, a small truncation can make the reflection coefficient increase rapidly, and the larger the truncation, the worse the vibration suppression effect. The combination form of one-dimensional acoustic black hole structure and damping material shows obvious formant suppression in the wide band range, and the larger the thickness of the damping layer and the closer the location of the damping layer to the tip, the more obvious the damping effect.

A machine learning method (MLM) developed based on fuzzy logic control (FLC) has been proposed to control the vibration of the car’s suspension systems. To apply the MLM, a quarter car model with two degrees of freedom has been established via MATLAB/Simulink. The reduction of the vertical car body’s acceleration response is the objective function. Through FLC’s logic rule and data maps of the different road surfaces, the MLM of ANFIS has been trained via its self-learning process to control the car’s suspension system. The result indicates that the vibration response of the car’s suspension system controlled by both FLC and MLM is reduced in comparison without the control. Particularly, the MLM has an obvious effect on reducing the acceleration response of the car body under different excitations of the road surface in comparison with the FLC. Consequently, the car’s suspension system controlled by the MLM could further enhance the car’s ride comfort compared to the traditional control methods.

To enhance the compacting performance and the asphalt density during the tamper-asphalt mixture interaction (TAMI), a dynamics model of the TAMI is established to analyze the compacting energy of TAMI under the different excitation frequencies of the compacting mechanism. The MATLAB/Simulink software is then applied to solve the vibration equations of TAMI based on the lumped parameters of the compacting mechanism and hot mix asphalt. The experimental research is also performed to verify simulation results and force distribution characteristics of the compacting mechanism on the asphalt pavement. The research results indicate that the vibration excitation of the compacting mechanism should be used in a range from 18 to 22 Hz and the number of vibrations of the compacting mechanism at the same position should be used by N= 4 or 5 to improve the compacting performance and the asphalt density. Additionally, the experimental results also show that the compacting force distribution of compacting mechanisms is asymmetric, thus, the design parameters of the vibration screed system should be optimized to enhance the compacting performance of the asphalt paver.

To control the cab shaking of the vibratory roller, an auxiliary damping mount (ADM) used for the cab isolation system in horizontal direction is proposed. Based on the off-road vibratory roller dynamic model under the conditions of the vehicle moving and compacting, the damping characteristic and installation position of the ADM for reducing vibration of the cab are respectively analyzed. The weighted root-mean-square (RMS) of acceleration responses of the vertical driver’s seat and pitching cab angle are chosen as the objective functions. The research results show the cab shaking is greatly reduced by using the ADM in comparison without ADM. Additionally, the drive’s seat vibration is also significantly decreased under both the compacting and moving conditions of the vibratory roller.

To evaluate the acceleration-frequency characteristics of the suspension system of the heavy vehicles, a nonlinear dynamic model of two-axle heavy vehicles is established. A calculation method based on the complex domain is applied to solve the vibration equations of the heavy vehicle in the frequency domain instead of the traditional time domain. Matlab software is then used to calculate the vibration equations under various operating conditions. The research results show that the resonant frequency of the suspension system is not affected by the vehicle speed and the road surface, while it is clearly influenced by the weight of the vehicle and the stiffness of the suspension system. However, the acceleration-frequency characteristics of the vertical vehicle body, pitching vehicle body, and vertical front/read axles are greatly influenced under various operating conditions, especially at the high speed 30 m.s-1, a wavelength of the road surface 6 m, and 80 % of the vehicle load.

The hydro pneumatic isolation (HPI) of the cab combined by the high static stiffness and nonlinear viscous damping of the pneumatic isolation; and nonlinear adjustable damping of the hydraulic isolation are proposed. Based on the simulation and experimental studies, a nonlinear dynamic model of the soil compactor interacting with the deformable terrains is built to analyze the low frequency ride comfort of the HPI. The HPI’s performance for improving the ride comfort and health of the driver is evaluated via both the power-spectral-density and root-mean-square of acceleration responses of the driver’s seat heave, pitching and rolling cab angles. The research results show that the HPI’s characteristics with high static stiffness and nonlinear damping have an obvious impact on reducing low frequency vibration and controlling the cab shake of the vehicle in comparison with the traditional rubber mounts.

To improve the soil compactor ride comfort, a combined control method of Fuzzy and PID control is proposed to control the cab isolation system of soil compactor based on the non-linear vehicle dynamic model. The vibration excitation sources are concerned by the vibrator drum and elastoplastic soil (EPS) interactions in the compression process. The power-spectral-density (PSD) and weighted root-mean-square (RMS) of acceleration responses of both the vertical driver’s seat and pitching cab angle are chosen as the objective functions. The research results show that both the PSD and weighted RMS values of the vertical driver’s seat and pitching cab angle are significantly reduced by using the PID-Fuzzy control under various EPSs in the low-frequency region, especially on the EPS with high-density.

The hybrid finite element method and statistical energy method was used to study the vibro-acoustic coupling characteristics of an engineering vehicle cab. The parameters of the statistical energy method, such as modal densities, damping loss factors and coupling loss factors of substructures, were acquired by numerical and analytical methods. The acoustic-structure coupling of the cab was established based on the modal densities of substructures. The vibration and noise excitations of the cab were measured by test and the sound pressure level response of the driver’s ear was predicted. It was shown that the prediction results based on the hybrid method are in agreement with the experiments and the proposed method can be applied to predict the mid-frequency response of complex vibro-acoustic coupling systems with a moderate computational cost and accuracy.

Hydraulic mounts can provide a better vibration attenuation performance than elastomeric mounts especially in the low frequency range. However, it is incapable of providing a response-dependent damper for the mount system to improve the ride comfort. In this study, a semi-active hydraulic cab mount (SHM) with control optimization was designed to improve ride comfort for the heavy vibratory roller. And a 7-DOF non-linear dynamic model of the vehicle was established for evaluation of the performance of hydraulic cab mounts based on different control optimization algorithms. To simulate roughness height the ISO level D road surface and deformed soil model were employed under the compaction work condition. The optimization study for two performance objectives as measured by responses of the vertical driver’s seat and cab pitch angle was carried out. It was shown that the SHM optimized by the fuzzy logic and proportional, integral, derivative controller methods (FLC-PID) giving best optimum values of the objective vector as compare to by multi-objective genetic algorithm (MOGA) and PID controller based on genetic algorithm (GA-PID).

This study proposes a combined method of the multi-body system theory and the Jourdain’s principle to study the automotive vibration. A 3D dynamic model of the automotive is built based on the multi-body system theory, the vibration equations are described based on two methods including a method of the Jourdain’s principle and the traditional method of the Newton-Euler’s principle. Matlab/Simulink software is used to solve the vibration equations under the excitation of the step road. The results show that the acceleration responses of the vertical, pitch and roll vibrations of the vehicle’s body with the Jourdain’s method are similarly in comparison with the traditional method. Therefore, the Jourdain’s method not only is applied for studying the kinetic and dynamic model of multi-body systems but also can be applied for studying the automotive vibration. Especially, nonlinear properties of objects in the vibration model can be clearly described by the Jourdain’s method via the recursive Jacobian matrices.

In this paper, unlike the existing studies, vibro-acoustic modeling and analysis of a rectangular acoustic cavity bounded by a flexible panel is conducted by three modeling techniques in a broad frequency range (up to 6.4 kHz). The finite element method (FEM) and statistical energy analysis (SEA) are employed at the low and high frequency range respectively. For the mid-frequency range, a hybrid FE-SEA method is employed to deal with the drawbacks in application of single deterministic or statistical methods. In this case, studies of the interior sound pressure and panel vibration responses for the structure-acoustic coupled system are made under external normal concentrated force acting at the flexible plate. And then comparisons are used to validate the three models and verify their accuracy through experimental investigations. Deviations between the numerical and test results are also discussed.