Abstract The safety and reliability of mechanical equipment are ensured by rolling bearings, which play a crucial role as vital elements rotating machinery. However, the complex fault features bearings cannot be fully characterized single-channel data, feature distribution is significantly varied under varying operating conditions, leading to substantial decline in model diagnostic performance. To address these issues, multi-channel data-driven domain adaptation (DA) method based on central...

Abstract Currently, the diagnostic performance of many deep learning algorithms may drop dramatically when distribution training data is significantly different from that test data. Moreover, fault diagnosis approaches based on single-channel suffer problems such as large precision fluctuation, low reliability, and incomplete expression features. To overcome above deficiencies, a novel multi-channel data-driven recognition method fusion sparse filtering (SF) discriminative domain adaptation...

To improve the ride comfort of vehicle and high-efficiency control requirements suspension, this paper proposes a time-delay strategy idea using linear motor as actuator. This analyses damping characteristics in time domain frequency domains. A equivalent excitation method is proposed to optimise optimal parameters under complex excitations. The stability system analysed. effect active suspension verified by numerical simulation. An experimental hardware platform was built further verify...

As the key component to transmit power and torque, fault diagnosis of rotating machinery is crucial guarantee reliable operation mechanical equipment. Regrettably, sample class imbalance a common phenomenon in industrial applications, which causes large cross-domain distribution discrepancies for domain adaptation (DA) results performance degradation most existing approaches. To address this issue, novel DA approach that simultaneously reduces difference geometric proposed, defined as MRMI....

A 2-DOF vehicle active suspension system model with time-delay feedback control is established. The stability region of the obtained by using Routh-Hurwitz criterion and polynomial discriminant theory. multi-objective optimization function established taking into account ride comfort, driving safety, handling stability, optimal parameters are particle swarm optimization(PSO) algorithm. vibration characteristics systems under different road excitations studied through experiments simulations...

The energy harvester based on the piezoelectric effect can convert vibration in environment into electricity to power network nodes. In order broaden effective frequency bandwidth of and reduce resonant system, a liquid slosh-type is proposed this paper. Based theory effect, mechanical model electromechanical coupling were established, dynamic characteristics slosh analyzed. theoretical experimental test, studied. By making prototype building experiment platform, capture tested...

The existing available research outcomes on vibration attenuation control for time-delay feedback indicate that, the delay dynamic absorber with fixed parameters, under harmonic excitation, a good effect occurs of main system. However, is not obvious complex excitation. Aiming at above problems, in short time interval, excitation same displacement size as was established. Then, by calculating its equivalent amplitude and frequency, method proposed this paper. parameters were adjusted...

A novel chitosan microsphere for encapsulating pine cone polyphenols (PP) from P. koraiensis was successfully prepared using an emulsion crosslinking technique. The characteristics of polyphenol-loaded microspheres (PPM) were determined scanning electron microscopy (SEM) and a laser particle size detector. It found that PPMs spherical in shape with uniform distribution patterns. drug content encapsulation rate the 7.47% 73.6%, respectively, at Ch/GA mass ratio 0.7. animal experiments showed...

Considering the nonlinear properties of spring and damping suspension, a quarter-car model with time-delayed control is established. The Routh–Hurwitz stability criterion switching method are used to analyze system obtain region diagram. multiobjective optimization function established by considering ride comfort, driving safety, handling stability. optimal parameters obtained simulation under harmonic excitation random excitation. In addition, responses active suspension time-delay passive...

The nonlinear time-delay dynamic absorber has a good control effect on the main system under harmonic excitation, but complicated excitation is not obvious. In previous study, they do have an effective method to obtain parameters different external excitations. Because of above problems, this paper proposed innovative absorbers. For vibration including absorber, transient time-integration was used solve delay differential equation specific excitation. Then, quantitative relationship...

In this paper, a nonlinear two-degrees-of-freedom active suspension system model with time-delayed feedback control is studied. It well known that time delay has destabilizing effect in mathematical models. A stability judgment method proposed, which produced the process of seeking analytic solutions by using multiple-scales method. The influence parameters on vibration reduction optimal parameter combination obtained. Numerical simulations are provided to support theoretical analysis....

<title>Abstract</title> This article focuses on the study of nonlinear active suspension tracking control problems based an adaptive reference model. To mitigate drawback compromised ride comfort caused by errors while trajectory body displacement, paper explores a controller with dual objectives. includes PD for desired and sliding mode concerning velocity acceleration. approach ensures that displacement approximately tracks significantly improving comfort, additionally, this method has...

Abstract This paper investigated the response and residual compression properties of honeycomb sandwich structures subjected to single quasi-static indentation (QSI) repeated QSI (RQSI). The damage depth after low-velocity impact (LVI) was considered as governing parameter during experiments. Three-dimensional digital image correlation method applied determine deformation front panels LVI describe structures. For specimens with same depth, it is found that strength less than close RQSI....

In this paper, the dynamic vibration absorber considering time delay is taken as research object, and effect of on characteristics studied by combining theory experiment. a time-varying time-delay feedback control method proposed. Firstly, instantaneous frequency complex excitation obtained wavelet analysis. The determines critical parameters with quantity. Then, optimal fixed gain calculated improved particle swarm optimization. Finally, parameter controls absorber. reduction approach under...