Drive Shaft System Research Articles

Research on Plunging Resistant Force of Drive-Shaft Systems Based on Fractal Methods

When drive-shaft systems move axially, the friction between rollers and raceways inside tripod joints will generate a plunging resistant force (PRF). Excessive PRF causes significant noise in vehicles. To reveal the generation mechanism, an analytical model of the PRF is proposed by analyzing the axial motion mechanism of a drive-shaft system. Based on the analytical model and fractal methods, a fractal model of the PRF is proposed to reveal influencing factors of the PRF more comprehensively. An effective method for correcting distribution of asperities between rollers and raceways is proposed to describe the contact state accurately. The fractal model shows that influencing factors of the PRF include the fractal dimension and the characteristic scale coefficient related to the roughness of contact surfaces, the material parameters, the working angle, and the correction coefficient for distribution of asperities. A measurement method for the PRF is subsequently proposed, and the fractal dimension and the characteristic scale coefficient are measured and determined. The effectiveness of the fractal model is verified based on the measurement of the PRF and the determined fractal dimension and characteristic scale coefficient. Numerical analysis results show that reducing Poisson’s ratio, the yield strength, and the working angle, increasing the characteristic scale coefficient, the elastic modulus, and the correction coefficient, and selecting a fractal dimension lower than 1.544 or higher than 1.782 can effectively reduce the PRF, thereby reducing the noise caused by the PRF.

Dynamic characteristics analysis and the identification signal of the horizontal tail drive shaft system with the ballistic impact damage of a helicopter

The ballistic impact damage (BID) will change the dynamic characteristics of the horizontal tail drive shaft system (HTDSS) and will directly affect the flight safety of the helicopter. Aiming at the problem of how the BID affects the dynamic characteristics of the HTDSS and how to identify the BID in time, the dynamic characteristics of the HTDSS with the BID are studied in this paper. The BID is simplified as the ideal geometric damage, and the calculation method of the BID is given. The finite element dynamic equation of the HTDSS with the BID is established, and the effect mechanism of the ballistic impact parameters on the dynamic characteristics is revealed. The result shows: the BID causes the mass loss and the stiffness asymmetric of the ballistic impact position of the TDS; the eccentric excitation introduced by the BID leads to the obvious increase of the system response, and the stiffness asymmetry leads to the super-harmonic resonance of the system. The obvious increase of system response and the appearance of 2Ω frequency component can be used as the identification signal of the BID. Finally, the experiment was carried out, which verified the correctness of the established dynamic model, and explained the reliability of the proposed identification signal of the BID.

Dynamic Modeling and Vibration Characteristics Analysis for the Helicopter Horizontal Tail Drive Shaft System with the Ballistic Impact Vertical Penetrating Damage

Dynamic Modeling and Vibration Characteristics Analysis for the Helicopter Horizontal Tail Drive Shaft System with the Ballistic Impact Vertical Penetrating Damage

Modeling and analysis of nonlinear axial friction forces of tripod joints considering roughness characteristics of contact pairs

The nonlinear axial friction force (NAFF) induced by contact and friction between components of tripod joints constitutes an important dynamic characteristic of drive-shaft systems, which will lead to deterioration of the NVH (noise, vibration and harshness) performance of the vehicle. Based on the fractal theory, this paper proposes a novel modeling and analysis method for accurate estimation of NAFF considering micro contact and friction characteristics of contact pairs. An analytical model is developed for estimating the NAFF of tripod joints considering micro contact and friction characteristics of contact pairs. In the process of modeling, a modified distribution function is proposed to describe distributions of contact asperities between the curved surfaces to describe the contact and friction states between the rollers and the tracks inside tripod joints more accurately. The developed analytical model suggests that NAFF is related to the fractal parameters, the material parameters, the operating conditions and the distribution of asperities. The effectiveness of the analytical model is demonstrated by comparing the model-predicted NAFF with the measured data. Based on the developed model of NAFF, the influences of important input parameters on the magnitude of NAFF are qualitatively analyzed. Subsequently, Sobol' global sensitivity analysis method is used to further investigate the influences of important input parameters on the magnitude of NAFF. The results show that the proposed modeling and analysis method for estimating NAFF are essential to characterize relationships among NAFF and fractal parameters, material properties and distribution of asperities from a micro level, which could facilitate design optimization of the tripod joints.

Thermal analysis method of optical scanning system drive shaft system

In order to improve the heating problem of the rotating shaft components of the optical surveillance scanning system due to continuous operation, the feasibility of applying the oil-air lubrication technology to the drive shaft system of the optical surveillance scanning system was studied. Analyzed the contact load of the spindle bearing, obtained the calorific value of the heat source of the spindle component of the drive system, established the finite element analysis model of the temperature field of the spindle component, and calculated the thermal stability of the spindle component under the conditions of no lubrication and lubrication. Temperature rise. It is proposed to apply the oil-air lubrication method to the drive shaft system of the optical monitoring scanning system, and the corresponding lubrication parameters are calculated.

Interval Optimization for Generated Axial Force of Drive Shaft Systems Considering Rough Surface Characteristics

Interval Optimization for Generated Axial Force of Drive Shaft Systems Considering Rough Surface Characteristics

Interval analysis and optimization of axial friction force of drive-shaft systems considering rough surface characteristics

Interval analysis and optimization of axial friction force of drive-shaft systems considering rough surface characteristics

Hybrid uncertainties-based analysis and optimization methods for axial friction force of drive-shaft systems

The axial friction force (AFF) of automotive drive-shaft systems is an important nonlinear dynamic characteristic, which will directly cause the vibration and noise of vehicles. During the operation of drive-shaft systems, the AFF has great uncertainty. Taking a drive-shaft system as the research object, a hybrid random and interval uncertainties (HRIU) model of the AFF is proposed to study the AFF more effectively. In the HRIU model, the articulation angle and the pitch circle radius of tripod joints are regarded as random variables, while the input torque, the shaft angular position and the friction coefficient are regarded as interval variables. To enhance the efficiency and accuracy of the analysis and optimization, a novel method called as the perturbation-vertex method is proposed to calculate the responses of the HRIU model. Due to complex responses of the HRIU model, in order to optimize the AFF more effectively, a reliability-based optimization method for the AFF under the HRIU is proposed, and the lower bound of the AFF reliability is taken as the optimization objective to determine the best design parameters of drive-shaft systems. A test bench for measuring the AFF is subsequently established together with the model verification, as well the analysis and optimization of the AFF with the HRIU are performed through numerical examples. The results suggest that the proposed perturbation-vertex method is very suitable for the analysis and optimization with the HRIU, as well the influence of the HRIU on the AFF cannot be ignored when analyzing and optimizing the AFF.

Analysis and optimization for contact forces and transmission efficiency of an automotive ball joint

Contact forces and transmission efficiency of an automotive ball joint constitute important design goals of an automotive drive shaft system, which affect transmission performances of the ball joint and the drive shaft system. In order to analyze contact forces and transmission efficiency more comprehensively, a multi-body dynamic model for calculating contact forces and transmission efficiency of a ball joint is established. The effectiveness of the multi-body dynamic model is validated through experiments of contact forces and transmission efficiency of a ball joint. Based on the developed multi-body dynamic model, influences of the articulation angle, the ball number and the track offset on contact forces between the ball and the cage, and between the ball and the track are analyzed. To enhance the analysis and optimization efficiency of transmission efficiency, a proxy model for the transmission efficiency loss late is established on the basic of the multi-body dynamic model. Influences of the ball radius, the articulation angle, the friction coefficient, the central angle of the cross section of the cage rib, and the contact stiffness and the force exponent of contact pairs on the transmission efficiency loss late are analyzed. Using Sobol’ global sensitivity analysis method, the sensitivity of the proxy model is analyzed and influences of various factors on the transmission efficiency loss late are further determined. According to sensitivity analysis results, the articulation angle, the friction coefficient and the force exponent are selected as design parameters, and the transmission efficiency loss late is optimized through a numerical example.

Analysis and optimization for generated axial force of a drive-shaft system with interval uncertainty

In the design of a drive-shaft system, the magnitude of the generated axial force (GAF) by the tripod joint constitutes an important design goal. Owing to the uncertainties associated with the drive-shaft system operating environment, and dimensional and material parameters, the GAF exhibits considerable uncertainty. In this study, a comprehensive model of a drive-shaft system is formulated together with interval uncertainties using Chebyshev polynomials for an accurate and efficient analysis of the GAF. The input torque, the articulation angle, the angular position of the drive-shaft, the pitch circle radius (PCR) of the tripod joint, and the friction coefficient between the rollers and the tracks that affect the GAF are taken as interval variables. The upper and lower bounds (ULB) of the proposed GAF model are subsequently established considering the interval uncertainty parameters using the vertex method, so as to assess the influence of GAF on the drive-shaft system response. The results suggest that the vertex method is far more computationally efficient and accurate for establishing the ULB of the GAF compared with the Monte Carlo method. The proposed model together with the vertex method is used to identify favorable drive-shaft design parameters through minimization of the upper bound (UB) response considering the uncertainty of the design and operating parameters. The effectiveness of the proposed method for the analysis and optimization of the interval uncertainty of the GAF is demonstrated through numerical examples and experiments. It is concluded that the interval uncertainty analyses and design optimization are essential in order to ensure that the UB of the GAF remains within the specification under interval uncertainties.

Analytical and experimental analysis of axial force generated by a drive shaft system

The drive shaft system with a tripod joint is known to cause lateral vibration in a vehicle due to the axial force generated by various contact pairs of the tripod joint. The magnitude of the generated axial force, however, is related to various operating factors of the drive shaft system in a complex manner. The generated axial force due to a drive shaft system with a tripod joint and a ball joint was experimentally characterized considering ranges of operational factors, namely, the input toque, the shaft rotational speed, the articulation angle, and the friction. The data were analyzed to establish an understanding of the operational factors on the generated axial force. Owing to the observed significant effects of all the factors, a multibody dynamic model of the drive shaft system was formulated for predicting generated axial force under different operating conditions. The model integrated the roller–track contact model and the velocity-based friction model. Based on a quasi-static finite element model, a new methodology was proposed for identifying the roller–track contact model parameters, namely, the contact stiffness and force index. To further enhance the calculation accuracy of the multibody dynamic model, a new methodology for identifying the friction model parameters and the force index was proposed by using the measured data. The validity of the model was demonstrated by comparing the model-predicted and measured magnitudes of generated axial force for the ranges of operating factors considered. The results showed that the generated axial force of the drive shaft system can be calculated more accurately and effectively by using the identified friction and contact parameters in the paper.

Effects of Silicone Oil on Stiffness and Damping of Rubber-Silicone Oil Combined Damper for Reducing Shaft Vibration

The helicopter tail drive shaft system is a typical multi-point supported drive shaft system, with a long span that can lead to serious vibration problems. Shaft vibration can be effectively reduced by installing a rubber-silicone oil combined damper between the bearing and bearing pedestal at the support point along the tail drive shaft. Stiffness and damping characteristics of the rubber-silicone oil combined damper are important factors affecting shaft vibration. In this study, the effects of silicone oil on the stiffness and damping of rubber-silicone oil combined damper were analyzed through simulations. The simulation method was experimentally verified and factors influencing the static stiffness, dynamic stiffness, and damping characteristics of the damper were investigated. In addition, the influence of damper dimensions and external excitation frequency on the stiffness and loss factor of the damping ring in the presence and absence of silicone oil were examined. The presence of silicone oil increases the difference between the dynamic stiffness and the loss factor. As the viscosity of the silicone oil increases, the static stiffness, dynamic stiffness, and loss factor of rubber-silicone oil combined dampers increase. The results have important guiding significance in the design of dampers for shafting systems.

Stability of a multi-body driveshaft system excited through U-joints

The disk-shaft system is a power transmission system with several industrial applications. The shafts, depending on the mechanism application, can be connected by U-joints through different rotating axes. In spite of the many advantages, these joints transform a constant rotating speed into a variable output one. Therefore, the multi-body system is self-excited that lead to dynamic instability. Here, a driveline system including three elastic shafts, which carry three disks, is considered. The oscillating behavior and resonance phenomenon of this fluctuating mechanism are investigated qualitatively and quantitatively. The angle of joints, damping and stiffness effects are the major topics of the present contribution. Eventually, dynamic stability diagrams are obtained by using a reliable and exact method based on the Floquet theory. It can be found that variations of the first U-joint angle and the intermediate shaft characteristics have greater impact on the machine instability. It is revealed how the stability of the system can be achieved by changing the geometry, shaft damping and stiffness, which should be considered in design and practical applications.

Design and automated manufacturing of profiled composite driveshafts

AbstractThe high specific strength and stiffness characteristics of composite materials such as carbon fiber-reinforced plastic (CFRP) allow a significant weight reduction of the structural machine components such as automobile driveshafts. But high material cost and rather low productivity of the established manufacturing processes (e.g., filament winding) often inhibit the use of CFRP components in a high-volume car series. In this paper, a novel composite driveshaft system based on a profiled CFRP tube is presented. This system is designed to be produced by a continuous pultrusion process to achieve a significant reduction of the manufacturing costs. A cost assessment study was conducted to quantify the benefit of the developed continuous manufacturing process. In comparison with the state-of-the-art filament winding process, a cost reduction of 36% for the composite shaft body can be obtained. Moreover, the proposed fiber layup processes – braiding and continuous winding – offer the potential to manipulate the reinforcement architecture to maximize material utilization without reducing the manufacturing efficiency. This potential is investigated and validated by experimental tests. A difference in the load bearing capacity of more than 100% between different reinforcing architectures is shown.

Stability region of floating intermediate support in a shaft system with multiple universal joints

A floating intermediate support is designed to reduce kinematic and dynamic fluctuations caused by the change of joint angles in a shaft system with multiple universal joints. The dynamic equation of the shaft system is derived via the principle of virtual work, which suggests the angular displacement of the input shaft is the only independent variable. A drive shaft system used in an articulated dump truck is taken as an example to analyze the sensitivities of shaft speed and input torque of the system about structural parameters and system variables, which proves the effectiveness of floating support to attenuate the kinematic and dynamic fluctuations of the shaft system. The stability region of floating support aimed at shaft speed and input torque of the system keeping relatively stable is obtained by setting proper upper limits of objectives, and the analysis results are verified by dynamic simulation in MapleSim platform, which is helpful to decide proper stiffness and damping or determine an optimum control strategy for floating angle of support in design.

Development of formula varsity race car chassis

Three chassis designs have been developed using commercial computer aided design (CAD) software. The design is based on the specifications of UTeM Formula VarsityTM 2012 (FV2012). The selection of the design is derived from weighted matrix which consists of reliability, cost, time consumption and weight. The score of the matrix is formulated based on relative weighted factor among the selections. All three designs are then fabricated using selected materials available. The actual cost, time consumption and weight of the chassis's are compared with the theoretical weighted scores. Standard processes of cuttings, fittings and welding are performed in chassis mock up and fabrication. The chassis is later assembled together with suspension systems, steering linkages, brake systems, engine system, and drive shaft systems. Once the chassis is assembled, the studies of driver's ergonomic and part accessibility are performed. The completion in final fittings and assembly of the race car and its reliability demonstrate an outstanding design for manufacturing (DFM) practices of the chassis.

Application of Numerical Simulation in Closed-Die Forging Forming for Universal Joint Fork

A universal joint fork is one of the key parts of the automotive and tractor drive shaft system, which needs high requirements in dimensional accuracy and product quality. In this study, the numerical simulation analysis of closed-die forging of the universal joint fork was carried out using the rigid-visco-plastic finite element model. In view of formation, heat transfer and heating generation coupled, the variation rules of forming load, stress field and strain field were obtained. The numerical simulation results show that good process parameters conditions can effectively control forming load, enhance metal flow and improve die life.

Rotor Dynamic Design of a Helicopter Tail Drive Shaft System

This document concentrates on the relationship between critical speeds and geometrical dimensions such as length, outer diameter, thickness, support stiffness and so on. An effective method was summarized for helicopter tail drive shaft system rotor dynamic design. A tail drive shaft system designed by this method was mounted in a helicopter and performed its first flight-test successfully. According to the feedback of tests in the air or on test bench, the vibration level of this shaft system was very low and rightly met the design requirements.

The high-pressure viscometer up to 400MPa with primary method of viscous moment measurements

A new high-pressure high-shear stress viscometer for pressure up to 400MPa, Couette type (rotational), has been developed. The wide shear rates range and shear stress can be applied for investigations of non-Newtonian liquids. The moment of viscous forces, acting in measuring viscosity cylinders, are measured outside of high-pressure chamber using primary method or using moment (force) sensors. That was realized by use of two counter rotating drive shaft systems with computer controlled stepped motors. As a pressure source a 10:1 intensifier with high-pressure manganin sensor were used.

Super harmonic nonlinear lateral vibrations of a segmented driveline incorporating a tuned damper excited by non-constant velocity joints

Typical industrial vibration problem solving includes utilization of linear vibration measurement and analysis techniques. These techniques have appeared to be sufficient with most vibration problem solving requirements. This is partially due to the lack of proper identification of the nonlinear dynamic response in measured data of actual engineering systems. Therefore, as an example, a vehicle driveshaft exhibits a nonlinear super harmonic jump due to universal joint excitations. This phenomenon is partially responsible for objectionable audible noise in the vehicle. Previously documented measurements or analytical predictions of vehicle driveshaft systems do not indicate nonlinear jump as a typical vibration mode. Physical measurements of the phenomena will be provided with subsequent analysis. Second, the secondary moment exciting the driveshaft system is derived with subsequent analysis showing the harmonic and super harmonic excitations. Third, a derivation of a model incorporating the linear and nonlinear modeling of a large degree of freedom system is introduced. Finally, simulations with the derived model with the universal joint excitations will be presented showing the correlation to physical test results. Therefore, a typical automotive driveshaft system is capable of producing nonlinear response, and thus the assumption of linearity is not sufficient for design validation or problem resolution in this case.