Belt-driven System Research Articles

Failure analysis in predictive maintenance: Belt drive diagnostics with expert systems and Taguchi method for unconventional vibration features

Predictive maintenance to avoid fatigue and failure enhances the reliability of mechanics, herewith, this paper explores vibrational time-domain data in advancing fault diagnosis of predictive maintenance. This study leveraged a belt-drive system with the properties: operating rotational speeds of 500–2000 RPM, belt pretensions at 70 and 150 N, and three operational cases of healthy, faulty and unbalanced, which leads to 12 studied cases. In this analysis, two one-axis piezoelectric accelerometers were utilized to capture vibration signals near the driver and pulley. Five advanced statistics were calculated during signal processing, namely Variance, Mean Absolute Deviation (MAD), Zero Crossing Rate (ZCR), Autocorrelation Coefficient, and the signal's Energy. The Taguchi method was used to test the five selected features on the basis of Signal-to-Noise (S/N) ratio. For classifications, an expert system was used based on artificial intelligence where a Random Forest (RF) model was trained on untraditional parameters for optimizing the accuracy. The resulted 0.990 and 0.999, accuracy and AUC, demonstrate the RF model's high dependability. Evidently, the methodology highlights the features potential when progressed into expert systems, which advances predictive maintenance strategies for belt-drive systems.

Bubble clustering in turbulent boundary layer on a moving wall utilizing belt-driven system

Bubble clustering in turbulent boundary layer on a moving wall utilizing belt-driven system

Equivalent Consumption Minimization Strategy Based on Belt Drive System Characteristic Maps for P0 Hybrid Electric Vehicles

A P0 system is used in hybrid automobiles to improve engine economy and performance. An essential element of the P0 system for effectively transmitting power to the drive train is the belt drive system (BDS). The features of electric machine (EM) and internal combustion engines (ICE) are taken into account by standard energy management systems, such as the equivalent consumption minimization strategy (ECMS). In order to maximize the effectiveness of the P0 system, this work provides a novel formulation of the ECMS, which considers the power loss map of the BDS in addition to the characteristic maps of EM and ICE. A test bench is built up to characterize the BDS, and it is verified using an open-loop Hardware in the Loop (HIL) in the WLTP driving cycle. To find the most appropriate equivalence factors for the ECMS, which would ordinarily be tuned through trial and error, a genetic algorithm (GA) is used. With regard to the standard ECMS, the proposed methodology intends to reduce fuel usage and CO2 emissions. Two belts in BDS were tested in the WLTP to achieve CO2 savings of 1.1 and 0.9 [g/km], indicating the enhancement of system performance by using the BDS power loss maps in ECMS.

Analysis on Noise Source of Claw Pole Machine in Duplex Three-Phase and Belt-Driven System

The acoustic noise, which is generated in a belt-driven integrated starter and generator (BSG) system, is the recent issue. By many studies, it has been known that the noise can be caused by both radial and tangential components of electro-magnetic force. A duplex three-phase claw pole type machine is widely used in the BSG system. In this case, due to its structural feature and difficulty in control, additional noises at unexpected frequency can be generated. In this paper, a method to analyze noise sources was proposed and applied to a prototype that is the duplex three-phase and claw pole type machine designed for BSG system. First, the electro-magnetic force was calculated by a finite-element analysis considering the unbalanced current measured by the experiment. The obtained force was decomposed according to the frequency and then analyzed. Through the force harmonics, additional noises according to the frequency, which are generated by the unbalanced claw shape in the axial direction and current imbalance between phases, were deduced. Finally, the predicted noise sources were compared with the noise measured through the experiment.

Prediction of Dynamic Stick-Slip Events in Belt-Drives Using a High-Fidelity Finite Element Model

AbstractA high-fidelity dynamic finite element model of a one-pulley belt-drive system is used to study how Coulomb friction coefficient and adhesion stress affect belt stick-slip events over driver and driven pulleys. The model shows that at Coulomb friction coefficient below a certain critical value, the belt undergoes pure sliding in the slip arc on driver and driven pulleys with no stick-slip dynamic events. Above that critical friction coefficient value dynamic stick-slip events start to occur in both driver and driven pulleys resulting in torque pulses, which for practical belt-drives may cause nonsmooth operation, excessive belt noise and/or excessive belt wear. For driver pulleys the dynamic stick-slip events are in the form of Schallamach waves, while for driven pulleys the dynamic stick-slip events are in the form of expansion pulses. The model results are validated using recently generated experimental results.

Detachment Waves and Self-Oscillation in a Belt-Drive System Incorporating Tensile Cords

Abstract Recent experimental studies have shown that tension transition via detachment waves (rather than via sliding, as commonly accepted) occurs at the belt–pulley interface for systems using simple homogeneous or textured flat belts operating under slow speeds. This raises the question of whether or not such detachment waves are universal—e.g., will they persist in systems incorporating belts with composite cross sections, such as those used in commercial applications? Herein, we experimentally explore the behavior of a belt-drive system incorporating a composite belt with tensile cords, with and without a patterned contact surface, and document the persistence of detachment waves. This then leads to a re-evaluation of the Firbank model of belt shear. We also explore the effect of tensile cords on (i) the amplitude and frequency of the observed detachment waves, (ii) the ensuing oscillations of the pulley, (iii) the evolution of belt shear strain, and (iv) the frictional losses of the system. We find that the detachment frequency increases and the pulley rotates steadier with inclusion of tensile cords. The corded belt undergoes shear deformation starting from the entry point due to a speed differential between the pulley envelope and the tension members, which is consistent with the classical Firbank shear model. However, the Firbank model cannot predict the rapid relaxation of the shear traction via detachment waves at the exit region. Additionally, accounting for shear and detachment events, we find that frictional losses in the belt-drive system decrease with inclusion of tensile cords.

Automated Waste Transfer System using Dedicated Corridor in Cities

The Waste disposal techniques have become quite old for the modern period lately. The transfer of waste from the waste bins in the localities through the use of compactor trucks needs to be changed. It stands low on the efficiency scale. This can be improved by Channelizing waste through a separate corridor. The idea is to channelize the waste underground by using belt conveyor systems. The waste collector bins in the localities will be joined to the main conveyor heavy duty belts by small conveyor belts to move the waste. This waste will be taken to the waste processing plants by the belts fixed underground. The waste collector bins will be equipped with the pressure plates and will be connected to the network. As soon as the bin is full, it will send the information to the control centre. The operator at the centre can empty the bin by clicking a button. This will help to live monitor the waste and move it as soon as possible. The waste which is channelized can be easily segregated at the end where it enters the waste processing plant. Segregation of the waste will allow us to reuse the recyclable materials which most of the time are dumped in the landfills. The idea is to eliminate the Compactor Trucks as they cause pollution and congestion. Also many a times, waste materials are dropped out from the truck while carrying them to the processing plants which affects the riders behind it. The smoke from the trucks is dark and sooty which are the main causes for the lung diseases. Whereas the belt driven system will work on electricity. This energy can be harnessed by renewable energy resources or by power plants where the efficiency is the highest.

Segmented, modular synchronous reluctance direct‐drive minimising the drive‐train costs

High-torque motors in direct-drive applications are advantageous especially with regard to the current trend of compact, cost-effective system integration. This paper discusses the concept of segmenting a synchronous machine and the resulting beneficial motor modularisation. Thereby, high-efficient, inverter-driven torque motors are possible, preferably for a speed range of up to 3000 rpm. The output power can be scaled from a few kilowatt up to higher power levels. This modularised, high-efficient motor enables a new dimension of system integration for many industries and applications. The motor segmentation, furthermore, allows an overall drive system cost optimisation while reducing the maintenance intensive components. How the drive-train cost changes when using a segmented motor is compared to a conventional belt-driven system.

Schallamach Wave-Induced Instabilities in a Belt-Drive System

We experimentally study the dynamic behavior of a belt-drive system to explore the effect of loading conditions, driving speed, and system inertia on both the frequency and amplitude of the observed frictional and rotational instabilities. A self-excited oscillation is reported whereby local detachment events in the belt–pulley interface serve as harmonic forcing of the pulley, leading to angular velocity oscillations that grow in time. Both the frictional instabilities and the pulley oscillations depend strongly on operating conditions and system inertia, and differ between the driver and driven pulleys. A larger net torque applied to the pulley generally intensifies Schallamach waves of detachment in the driver case but has little influence on other measured response quantities. Higher driving speeds accelerate the occurrence of frictional instabilities as well as pulley oscillations in both cases. Increasing the system's inertia does not affect the behavior of contact instabilities, but does lead to a steadier rotation of the pulley and more pronounced fluctuations in the belt tension. A simple dynamic model of the belt-drive system demonstrates good agreement with the experimental results and provides strong evidence that frictional instabilities are the primary source of the system's self-oscillation.

Efficient 48V Application

Research and development into 48V applications in mild hybrid electric vehicles calls for efficient delivery of power, overcoming the challenges of belt-driven systems

Modeling and dynamic analysis of accessory drive systems with integrated starter generator for micro-hybrid vehicles

Belt-driven integrated starter generator system is a hybrid transmission that resembles the conventional serpentine belt-driven system. The system contains an integrated starter generator that performs a “start-stop” function on the engine. A two-pulley tensioner mechanism is attached to the integrated starter generator to maintain belt tension. The objectives of this paper are to develop modeling and calculation methods for estimating the performances of the belt-driven integrated starter generator system and to investigate the influence of damping of the two-pulley tensioner on vibration and shock. A systematic modeling and analysis method is proposed. The modeling method for the two-pulley tensioner is distinguished from any existing studies, which are generic for modeling the tensioner in belt-driven integrated starter generator systems with different layouts. A typical belt-driven integrated starter generator system is presented and a model is established to predict the dynamic response of rotational vibrations of pulleys, tensioner motions, and tension fluctuations. A parametric analysis is conducted to evaluate the two-pulley tensioner parameters with respect to their impact on the performances of the belt-driven integrated starter generator system.

Vibration reduction effect of one-way clutch on belt-drive systems

Abstract In order to study the vibration reduction effect of the one-way clutch on belt-drive systems, especially on the transporting belt, an experimental platform is built. The strongest resonant areas of the midpoint of the transporting belt with and without the one-way clutch are compared. The experimental results clearly show the vibration reduction effect of the one-way clutch on the resonance of the belt-drive system. In order to determine the optimum vibration reduction parameters of the one-way clutch, a two-pulley belt-drive dynamic model coupled is established. The commonalities between numerical simulation and experimental research are the inclusion of a translating belt, a driving pulley, a driven pulley and an accessory pulley. The difference is that there is no connection between the physical parameters of the numerical simulation and experimental studies. By establishing the relationship between the longitudinal vibration and transverse vibration of the translating belt spans, the coupled governing equations of the belt-drive system are derived to describe the coupling of the transverse vibration of the transporting belt and rotation of the pulleys. The natural frequency of the belt is determined by using the amplitude spectrum of the free vibration response of the system. Numerical results illustrate that the two main parameters of the one-way clutch, the wrap spring and the pre-load have little effect on the natural vibration frequency of the belt. However, these two main parameters are very sensitive to the vibration reduction effect of the one-way clutch. Therefore, this study is very helpful to understand the optimal design of the one-way clutch.

Dynamic Analysis of an Automotive Belt-Drive System With a Noncircular Sprocket by a Modified Incremental Harmonic Balance Method

A dynamic model of an automotive belt-drive system with a noncircular sprocket instead of a round sprocket is developed in this work to study the effect of reducing the angular variation of camshafts. There are two submodels in the belt-drive system, which are an engine model and a belt-drive model, and they are decoupled to simplify the analysis. When the belt-drive system operates at a steady-state, it is described by a nonlinear model with forced excitation, which can be approximated by a linear model with combined parametric and forced excitations. Steady-state responses of the engine and belt-drive models are calculated by a modified incremental harmonic balance method that incorporates fast Fourier transform and Broyden's method, which is efficient and accurate to obtain a periodic response of a multi-degree-of-freedom system. Steady-state responses of the angular variation of camshafts with different values of sprocket parameters are compared to investigate their optimal values to reduce the angular variation of camshafts. The optimal eccentricity and installation angle are larger and smaller than those from the kinematic model, respectively, which is consistent with published experimental results. This study first shows from a dynamic point of view why use of a noncircular sprocket can reduce the angular variation of camshafts in the operating speed of an engine. Simulation of a speed-up procedure for different sprocket parameters shows results that are consistent with steady-state responses. The belt-drive model developed in this work can be used to select sprocket parameters to minimize the angular variation of camshafts and numerically evaluate the dynamic performance of a belt-drive system with a given design of sprocket parameters.

Intelligent Belt Drive Systems in Hybrid Powertrains: a Multipurpose Test Rig

Abstract: In traditional engine setups Belt Drive Systems (BDS) are in charge of power transmission from the crankshaft to the accessories. They are complex and critical dynamic mechanisms, involving contact mechanics and vibration phenomena. The hybridization of vehicles has increased the severity of the operating conditions of these systems that have become even more critical. The traditional alternator was substituted by a Belt-Starter Generator (BSG), an electric machine that can power the BDS in particular operating conditions to improve the Internal Combustion Engine (ICE) performance or to allow regenerative braking. The aim of the present work is to describe the design and the main characteristic of a test rig conceived to investigate in laboratory environment on the behaviour of belt drive systems in dynamic conditions. Two permanent magnet electric motors are used to replicate the dynamic behavior of crankshaft and BSG in a realistic, though controlled and repaetable, manner.

Steady-state responses of a belt-drive dynamical system under dual excitations

The stable steady-state periodic responses of a belt-drive system with a one-way clutch are studied. For the first time, the dynamical system is investigated under dual excitations. The system is simultaneously excited by the firing pulsations of the engine and the harmonic motion of the foundation. Nonlinear discrete–continuous equations are derived for coupling the transverse vibration of the belt spans and the rotations of the driving and driven pulleys and the accessory pulley. The nonlinear dynamics is studied under equal and multiple relations between the frequency of the firing pulsations and the frequency of the foundation motion. Furthermore, translating belt spans are modeled as axially moving strings. A set of nonlinear piecewise ordinary differential equations is achieved by using the Galerkin truncation. Under various relations between the excitation frequencies, the time histories of the dynamical system are numerically simulated based on the time discretization method. Furthermore, the stable steady-state periodic response curves are calculated based on the frequency sweep. Moreover, the convergence of the Galerkin truncation is examined. Numerical results demonstrate that the one-way clutch reduces the resonance amplitude of the rotations of the driven pulley and the accessory pulley. On the other hand, numerical examples prove that the resonance areas of the belt spans are decreased by eliminating the torque-transmitting in the opposite direction. With the increasing amplitude of the foundation excitation, the damping effect of the one-way clutch will be reduced. Furthermore, as the amplitude of the firing pulsations of the engine increases, the jumping phenomena in steady-state response curves of the belt-drive system with or without a one-way clutch both occur.

Dynamic analysis and parameter estimation of coupled three-link planar manipulator with flexible belt-drive system

The coupled three-link planar manipulator mechanism is widely adopted in panel handling robots for the realization of straight-line translational motion of the end-effector with a single actuator and three belt-drive systems. This research analyzes and models the complex dynamics of the coupled three-link planar manipulator including the flexible belt systems. Equations of the motion of the manipulator are derived mathematically by using Lagrange method and the coupling constraints between the links are modeled and appropriately represented in the mathematical model. Also, joint friction is modeled with static, Coulomb and viscous models. Using the mathematical model a numerical simulation program is developed. The system parameters, including joint friction and belt damping, for the highly nonlinear model are estimated using the genetic algorithm that is one of the global optimization techniques. The validity of the simulation model is verified by comparing the simulation results with the experimental results.

Static and dynamic behaviors of belt-drive dynamic systems with a one-way clutch

This paper focuses on the nontrivial equi- librium and the steady-state periodic response of belt- drive system with a one-way clutch and belt flexural rigidity. A nonlinear piecewise discrete-continuous dynamic model is established by modeling the motions of the translating belt spans as transverse vibrations of axially moving viscoelastic beams. The rotations of the pulleys and the accessory are also considered. Further- more, the transverse vibrations and the rotation motions are coupled by nonlinear dynamic tension. The nontriv- ial equilibriums of the belt-drive system are obtained by an iterative scheme via the differential and integral quadrature methods (DQM and IQM). Moreover, the periodic fluctuation of the driving pulley is modeled as the excitation of the belt-drive system. The steady- state periodic responses of the dynamic system are, respectively, studied via the high-order Galerkin trun- cation as well as the DQM and IQM. The time his- tories of the system are numerically calculated based on the 4th Runge-Kutta time discretization method. Furthermore, the frequency-response curves are pre- sented from the numerical solutions. Based on the steady-state periodic response, the resonance areas of the dynamic system are obtained by using the fre- quency sweep. Moreover, the influences of the trun- H. Ding (B)· D.-P. Li

Efficient and ‘Green’ Vehicle Air Conditioning System Using Electric Compressor

Reducing energy consumption and ensuring thermal comfort are two important considerations in designing vehicle air conditioning system. Alternative approach to reduce energy consumption proposed in this study is to use an electrically-driven compressor (EDC) powered by a 12-volt lead-acid vehicle battery which is charged by the alternator. This system makes the speed of compressor to be independent of the engine crankshaft speed. Typical belt-driven compressor of automotive air conditioning system (AAC) caused cooling capacity to vary with engine speed. The current research activity focuses on the experimental investigation on cabin temperature and fuel consumption of a 1.3 liter 5 seater hatchback vehicle on roller dynamometer at variable speed of 1800, 2000, 2200, 2400 and 2500rpm with internal heat load of 1000W at temperature set-point of 21°C. The overall experimental results show that the performance of EDC is better than the conventional belt-driven system with the opportunity for a better energy control.

Equilibria and Free Vibration of a Two-Pulley Belt-Driven System with Belt Bending Stiffness

Nonlinear equilibrium curvatures and free vibration characteristics of a two-pulley belt-driven system with belt bending stiffness and a one-way clutch are investigated. With nonlinear dynamical tension, the transverse vibrations of the translating belt spans and the rotation motions of the pulleys and the accessory shaft are coupled. Therefore, nonlinear piecewise discrete-continuous governing equations are established. Considering the bending stiffness of the translating belt spans, the belt spans are modeled as axially moving beams. The pattern of equilibria is a nontrivial solution. Furthermore, the nontrivial equilibriums of the dynamical system are numerically determined by using two different approaches. The governing equations of the vibration near the equilibrium solutions are derived by introducing a coordinate transform. The natural frequencies of the dynamical systems are studied by using the Galerkin method with various truncations and the differential and integral quadrature methods. Moreover, the convergence of the Galerkin truncation is investigated. Numerical results reveal that the study needs 16 terms after truncation in order to determine the free vibration characteristics of the pulley-belt system with the belt bending stiffness. Furthermore, the first five natural frequencies are very sensitive to the bending stiffness of the translating belt.

Effect of one-way clutch on the nonlinear vibration of belt-drive systems with a continuous belt model

This study focuses on the nonlinear steady-state response of a belt-drive system with a one-way clutch. A dynamic model is established to describe the rotations of the driving pulley, the driven pulley, and the accessory shaft. Moreover, the model considers the transverse vibration of the translating belt spans for the first time in belt-drive systems coupled with a one-way clutch. The excitation of the belt-drive system is derived from periodic fluctuation of the driving pulley. In automotive systems, this kind of fluctuation is induced by the engine firing harmonic pulsations. The derived coupled discrete–continuous nonlinear equations consist of integro-partial-differential equations and piece-wise ordinary differential equations. Using the Galerkin truncation, a set of nonlinear ordinary differential equations is obtained from the integro-partial-differential equations. Applying the Runge–Kutta time discretization, the time histories of the dynamic response are numerically solved for the driven pulley and the accessory shaft and the translating belt spans. The resonance areas of the coupled belt-drive system are determined using the frequency sweep. The effects of the one-way clutch on the belt-drive system are studied by comparing the frequency–response curves of the translating belt with and without one-way clutch device. Furthermore, the results of 2-term and 4-term Galerkin truncation are compared to determine the numerical convergence. Moreover, parametric studies are conducted to understand the effects of the system parameters on the nonlinear steady-state response. It is concluded that one-way clutch not only decreases the resonance amplitude of the driven pulley and shaft's rotational vibration, but also reduces the resonance region of the belt's transverse vibration.