Intermediate Shaft Research Articles

Parametric Optimization of Linear Ball Bearing with Four-Point Connection in Steer-by-Wire Steering Column by Means of Genetic Algorithm

This paper presents the process of the optimization of linear ball bearings with four-point connection using a genetic algorithm and the finite element method. Currently, modern steering systems without an intermediate shaft—steer-by-wire systems—are being developed. The focus of this paper was on the optimization of linear ball bearings with four-point connection, embedded between the outer and inner columns tube in terms of the number of balls in the bearing and the clearance between balls. The aim of the research was to maximize the first two natural frequencies in the steering system, which is crucial for improving the stability and efficiency of the system. Various factors influencing natural vibration such as bearing geometry, raceway and ball materials, and operating conditions (preload) were taken into account in the research. Preload is a major factor affecting not only linear motion but also natural frequency. In order to speed up the calculations, the author’s simplified model of a linear bearing with the use of a system of springs was proposed. The nonlinear properties of the spring were determined on the basis of Hertz’s theory. A genetic optimization process resulted in a linear bearing structure that meets the natural frequency criteria. In addition, the full reference model was numerically compared with the simplified one, which showed convergent results of natural frequencies.

Modal analysis of tripod-ball type universal coupling composite transmission shaft system

Abstract In order to improve the dynamic performance of the tripod-ball type universal coupling composite transmission shaft system, ANSYS Workbench modal analysis is carried out. By modal analysis of the transmission shaft system, the vibration characteristics of the coupling have been obtained, which can avoid its natural frequency in practical situations. The figures for the first ten modes have been obtained. The results indicate that the areas with the greatest deformation are on the intermediate shaft, bell housing, and trident sleeve. This provides a theoretical basis for further research on the transmission shaft system.

Research on a Real-Time Control System for Discrete Factories Based on Digital Twin Technology

Gear factories are most typical discrete manufacturing factories. Many gear factories are striving to explore how to achieve intelligent manufacturing in order to improve efficiency and reduce costs. Digital twin technology is currently one of the most reliable ways to achieve intelligent manufacturing. This article aims to establish a real-time control system in order to promote intelligent manufacturing for discrete manufacturing factories. Firstly, a model for a digital twin gear factory is put forward based on the characteristics of gear factories, and the composition of a real-time control system for gear factories is clarified. Then, a human–computer interaction architecture for the real-time control system is proposed. The real-time control system consists of three parts as follows: a monitoring module, a virtualizing module, and a controlling module. At work, it appears as a kind of human–machine interaction form with the three following interfaces: a monitoring window, a virtualizing window, and a controlling window. Finally, a gear factory, which is specialized in manufacturing the intermediate shaft dual gear of a new energy vehicle gearbox, develops a set of software for the real-time control system. The prototype software is obtained through some development activities such as 3D MAX and WebGL virtualization modeling and OPC UA and REST communication design.

An Analysis of the Kinematics and Dynamics Performance of a New Type of Three-Pronged Sliding Universal Coupling

The three-pronged sliding universal coupling is a new kind of three-pronged coupling. The purpose of this study is to demonstrate that, compared with a traditional unequal angular velocity universal coupling (such as the Hooke universal coupling), the universal coupling has the superior characteristics of constant angular speed transmission, simple structure and strong transmission capacity by performing kinematic and dynamic analysis of the new three-pronged sliding constant angular velocity universal coupling. It provides a broad prospect for applications in automotive and other fields. To study its kinematic and dynamic characteristics, directional cosine matrices are utilized as tools to analyze the coordinate systems by establishing simplified geometric models and corresponding motions. Through the analysis of the motions of the input and output shafts and employing the method of single-force element, a set of equilibrium equations for the forces acting on the output shaft and the input shaft are formulated for solution analysis. The research indicates that during the rotation process, there exists a small angular difference between the input shaft and the intermediate shaft, demonstrating the quasi-constant angular velocity characteristics of the new tripod sliding universal coupling. The curves of the forces and force moment acting on each component of the coupling approximate sinusoidal curves. The optimal operating angle range for the new tripod universal coupling is at angle , during which the system exhibits good transmission and mechanical performance. It can be widely used in the automobile industry, tie steel industry and other occasions that require angular transmission. It is especially used in high-speed operation and large transmission capacity.

A trade-off optimization model of environment impact and manufacturing cost for machining parts

Motivation: Throughout the life cycle, the environmental impact and manufacturing costs of a part are largely determined at the design stage. Therefore, a part design optimization method considering these two factors is proposed in this paper. At the same time, the comprehensive benefit is taken as the trade-off of these two factors. The reduction of the comprehensive benefit indicates that the optimized part has achieved better environmental and economic performance results. Methods: Firstly, the model is reconstructed using the dimension-driven method, and the feature information of the new part is extracted. Then, machining process planning is carried out based on the feature information. Secondly, a design optimization model for the comprehensive benefit is established based on the genetic algorithm. The model takes the dimension parameters of the part as the optimization variables and the reduction of the comprehensive benefit as the optimization objective. With the help of the Simulation plug-in for SolidWorks, the static analysis of the optimized model is conducted to determine whether it meets the performance requirements. Finally, the design optimization prototype system oriented to comprehensive benefit is established. The feasibility and effectiveness of the proposed method are verified by taking the intermediate shaft of the belt conveyor reducer-sixth order step shaft as an example. Results: The case study shows that the optimization result of comprehensive benefit is 1.63%, which verifies the feasibility and effectiveness of the part design optimization method proposed in this paper.

The risk matrix application to assess the installation of torsional vibration monitoring systems on ships

According to statistics, the number of accidents related to the failures of ship engine and propulsion systems remains in second place among the total number of accidents. One of the reasons for the destruction of diesel crankshafts, intermediate and propeller shafts, elastic couplings and other elements of shaft lines are torsional vibrations in combination with other types of fluctuations and vibrations. The main method for monitoring the level of torsional vibrations in ship’s shaft lines remains periodic torsiography or strain measurement. The widespread introduction of diagnostic and control systems on ships leads to the technical possibility of constant monitoring of the level of torsional vibrations, which will allow you to reduce the risks of accidents in the periods between torsiography. Like any new technical solution, the introduction of torsional vibration monitoring systems requires a scientific justification of the need for their application, which can be carried out with using risk theory. The results of applying the risk matrix to justify the installation of torsional vibration monitoring systems in marine propulsion systems are presented in the paper. As a result, a risk matrix with quantitative parameters is obtained to justify the installation of torsional vibration monitoring systems and reduce the risks of ship’s shaft line breakdowns. As an example, the application of the risk matrix for “OT” type tugs, which are widely used for various operations on the Russian waterways, is considered. It is established that for these types of vessels, the use of a monitoring system will be justified to reduce the risks of accidents, serious accidents and catastrophes that may arise from the development of dangerous torsional vibrations. A method for applying the assessment of the damage degree from an accident occurrence to determine the reduction of economic costs when using torsional vibration monitoring systems is proposed in the paper. It is found that for the “OT” type tugs, the installation of torsional vibration monitoring systems will be justified, both from the point of view of economics and reducing the accidents risks of ship engine and propulsion systems.

Cortical bone architecture of hominid intermediate phalanges reveals functional signals of locomotion and manipulation.

Reconstruction of fossil hominin manual behaviors often relies on comparative analyses of extant hominid hands to understand the relationship between hand use and skeletal morphology. In this context, the intermediate phalanges remain understudied. Thus, here we investigate cortical bone morphology of the intermediate phalanges of extant hominids and compare it to the cortical structure of the proximal phalanges, to investigate the relationship between cortical bone structure and inferred loading during manual behaviors. Using micro-CT data, we analyze cortical bone structure of the intermediate phalangeal shaft of digits 2-5 in Pongo pygmaeus (n = 6 individuals), Gorilla gorilla (n = 22), Pan spp. (n = 23), and Homo sapiens (n = 23). The R package morphomap is used to study cortical bone distribution, cortical thickness and cross-sectional properties within and across taxa. Non-human great apes generally have thick cortical bone on the palmar shaft, with Pongo only having thick cortex on the peaks of the flexor sheath ridges, while African apes have thick cortex along the entire flexor sheath ridge and proximal to the trochlea. Humans are distinct in having thicker dorsal shaft cortex as well as thick cortex at the disto-palmar region of the shaft. Variation in cortical bone distribution and properties of the intermediate phalanges is consistent with differences in locomotor and manipulative behaviors in extant great apes. Comparisons between the intermediate and proximal phalanges reveals similar patterns of cortical bone distribution within each taxon but with potentially greater load experienced by the proximal phalanges, even in knuckle-walking African apes. This study provides a comparative context for the reconstruction of habitual hand use in fossil hominins and hominids.

Bearing fault damage degree identification method based on SSA-VMD and Shannon entropy–exponential entropy decision

Aiming at the problem that the weak fault signal of rolling bearing is affected by background noise and the weak fault signal itself leads to the difficulty in extracting fault features, a weak fault diagnosis method of rolling bearing based on sparrow search algorithm-variational mode decomposition (SSA-VMD) and Shannon entropy–exponential entropy decision is proposed. Firstly, the failure energy ratio of the original signal is acquired to judge the bearing failure. Secondly, the original time-domain signal is decomposed by the VMD optimized by SSA-VMD to obtain the Intrinsic Mode Function (IMF) component, and the kurtosis and correlation coefficient are normalized and fused. The fusion parameter ratio (RV) is used to filter the IMF component, and the filtered component is reconstructed to achieve the noise reduction effect. The reconstructed signal is subjected to Hilbert transform to obtain the envelope spectrum of the vibration signal, and the fault type of the bearing can be judged. Finally, the entropy of the reconstructed signal is input into the model based on entropy-multilayer forward neural network (MFNN) to identify the degree of bearing fault damage. The effectiveness of the method is verified by using the experimental data of different fault types of intermediate shaft bearings in Shenyang Aerospace University and the self-built experimental data of outer ring fault detachment evolution. The results show that the fault energy ratio of the original signal is more conducive to judging whether the bearing has a fault than the reconstructed signal. The bearing fault type diagnosis method based on SSA-VMD and parameter fusion screening can effectively identify fault characteristic frequency and its frequency doubling of the inner and outer rings of rolling bearings. The entropy values of different bearing damage signals have different distribution regions, which verify the effectiveness of the bearing fault damage identification method based on entropy–MLP judgement.

СОВЕРШЕНСТВОВАНИЕ ТЕХНОЛОГИИ ДИАГНОСТИРОВАНИЯ ОПОРНЫХ УЗЛОВ ТРАНСМИССИИ АВТОМОБИЛЯ КАМАЗ-55111

The paper presents trends in the development of automatic diagnostics systems for mechanical transmission units. (Research purpose) The research purpose is substantiating the technology of automatic identifying the pre-failure condition of transmission units. (Materials and methods) The supporting components of the KamAZ-55111 transmission with rolling bearings 50412 and 53610 were chosen as the research material. The analysis of existing methods of labor intensity, methods for calculating machine parts, reference information on bearings, finite element analysis of temperature fields and regression analysis were used. (Results and discussion) The characteristics of the indicators of the transmission support units (rolling bearings) were described, methods of their diagnosis were considered. The forces acting on the bearings on the secondary and intermediate shafts of the KamAZ-55111 car were calculated. The design, technological and operational parameters were used to calculate the temperature in the friction zone. In order to improve the diagnostic technology, temperature fields were simulated using the APM FEM CAD Compass 3D application. A device for automatic temperature measurement in the friction zone and a sensor for temperature measurement have been developed. (Conclusions) The reliability of the transmission support units of agricultural machinery is affected by the working conditions. It was established that the most effective method of diagnosing the complexity of the transmission is the method of thermodiagnostics. Analysis of the temperature in the friction zone of bearings 50412 and 53610 from first to fourth gear showed a decrease in temperature. The study of temperature field maps made it possible to establish the relationship between the temperatures in the friction zone and in the control zone of bearings 50412 and 53610. A recorder for automatic monitoring of the technical condition of the nodes has been developed and tested.

Wind tunnel experimental study on static aerodynamic performance of SB-VAWT without intermediate support axes

Wind power generation is considered an effective way for ships to harness wind energy, and the aerodynamic characteristics of wind turbines determine wind energy utilization and efficiency. However, traditional vertical axis wind turbines have intermediate shafts and support rods, which result in large negative effects in the research of the wind turbine aerodynamic characteristics. To address this issue, a Straight-Bladed Vertical Axis Wind Turbine (SB-VAWT) without intermediate support axes is proposed. The turbine can flexibly change the number of blades, rotor diameter, and installation position of blades. The static aerodynamic performance of the wind turbine with different combinations was tested in a wind tunnel laboratory at 10 m/s. The results show that the radius of the wind turbine has a greater effect on the drag coefficient for the same number of blades, with an inverse relationship between the drag coefficient and radius, and a positive association between lift coefficient, static torque coefficient, and radius. The drag coefficient is proportional to the number of blades at the same radius, while the static torque coefficient is inversely proportional to the number of blades. According to the results, placing the initial location in the azimuth range between 30° and 50° can obtain the maximum initial starting torque. Moreover, a wind turbine with a radius of 16 cm can achieve a higher average torque. Changes in the number of blades can significantly impact turbine properties, resulting in wind turbines with distinct features.

Experimental Study of Geysering in an Upstream Vertical Shaft

Transient flows in stormwater systems can lead to damaging and dangerous operational conditions, as exemplified by geysering events created by the uncontrolled release of entrapped air pockets. Extreme rain and associated rapid inflows may result in air pocket entrapment, which causes significant changes in flow conditions and potentially geysering. Stormwater geysers have been studied in different experimental and numerical modeling studies, as well as from limited data gathered within real systems. However, there is still no complete understanding of geysering events, as stormwater system geometries vary considerably. Most past studies involved releasing air from an intermediate shaft, in which a significant fraction of the entrapped air may bypass the release. This work advances the understanding of geysering by considering uncontrolled air release through an upstream shaft or manhole. In such cases, the entire air pocket is released upon reaching the shaft, worsening the occurrence of geysering. Pressure and water level measurements were performed for various combinations of initial water pressure, trapped air pocket volume, and vertical shaft geometries, indicating the higher severity of these geysering events. The results obtained also corroborate previous studies in that the measured pressure heads were lower than the grade elevation. Future studies should include larger-scale testing and the representation of this geometry using CFD.

Influence of the Fixed Angle of the Non-Circular Gears on the Intermediate Shaft on the Gear Ratio Function Characteristics

The paper shows the influence of the fixed angle of non-circular gears (NCGs) on the gear ratio function characteristics of the compound non-circular gear (CNCG) train. The research established a mathematical model describing the centrodes of a typical CNCG train. The fixed angle β of non-circular gears on the intermediate shaft is changed to evaluate its effect on the gear ratio of the CNCG train. The results show that changing the fixed angle of non-circular gears on the intermediate shaft changes the transfer function law of the system and can increase the speed variation range on the output shaft. With the parameters of the designed CNCG train, changing the angle β can increase the amplitude of the gear ratio function to 30.19%. A CNCG train with a speed variation range from 1.37 to 5.11 has been experimentally designed and manufactured with an improved cycloid profile considering the tooth number distribution and satisfying the condition of avoiding undercutting. On that basis, an experimental system to determine the gear ratio of the CNCG train based on the meshing between the gear pairs in the CNCG train has been designed and manufactured. The experimental results showed that the maximum error of the gear ratio function is about 7.63% compared with theoretical ones. In this study, we have not considered the influence of force and torque on the experimental gear ratio. We can apply the results of this research to transmission systems to obtain a speed variation.

Structural Analysis of a Hollow Intermediate Shaft for Mass Reduction

Structural Analysis of a Hollow Intermediate Shaft for Mass Reduction

Designing a Computer Simulation Model to Study the Failure Mechanism in Rotating Shaft

The phenomenon of the failure of rotating mechanical structures is considered one of the dangerous phenomena that researchers are trying to study to find effective ways to avoid it. Many mathematical models describing the mechanism of crack formation in structures and the occurrence of failure in them have been adopted. In this paper, a computer simulation model of the failure mechanism in the intermediate conduction shaft of the ship's propeller (oil shuttle tanker) was designed based on the mathematical model that describes the stages of failure according to the number of revolutions that the shaft bears and the dimensions of fatigue cracks in it. In the beginning, a detailed mathematical model of the crack propagation mechanism was deduced as an initial stage, through which the differential equations that express the failure of the shaft were described. In the second stage, numerical simulations were implemented using the Euler and Rung-Kutta numerical methods used in solving ordinary differential equations. Also, for both methods using the Matlab language to reach the results and accurate graphs and analyze them. In this way it is possible to predict the number of cycles that the column will bear before the collapse, and this will reduce the occurrence of sudden collapses and save time, effort, and costs.

Computational Structural Analysis for Torsional Stiffness Test of Intermediate Shaft Assembly

Computational Structural Analysis for Torsional Stiffness Test of Intermediate Shaft Assembly

A new approach to solving the problems of increasing the efficiency of geothermal field development

The initial prerequisites for the effective development of geothermal deposits have been developed. Geological – reliable information about the geological structure of thermal water deposits, compositions, physical and mechanical properties of rocks in the “water-rock” system. Technical – means of well construction, design features and technological capabilities corresponding to the conditions of the mining environment, ensuring the production of highly informative geological material in the form of a core, maintaining the stability of the walls of wells from collapse and shedding. A series of diamond drill bits with a hydrojet effect of rock destruction, corresponding to the conditions of opening hot springs, have been developed and tested in practice for drilling wells. A scheme of a circulation system for the opening and development of geothermal deposits consisting of a vertically injection and an obliquely ascending well connected by a smooth bend of an intermediate shaft is proposed. The ideological novelty of the scheme, which differs from all known schemes for the development of geothermal deposits in the world, provides for the possibility of creating conditions for the manifestation of the internal energy of the earth’s interior and the thermal horizon, aimed at improving the efficiency of the development of geothermal deposits. The structural features of the scheme are that a vertical injection well lined with a filter column in the section of the thermal horizon is made with ledges, where shock waves of increased and decreased pressure are generated when water is supplied, by dividing the water flow into a central core and lateral components. As a result, the thermal horizon is affected by alternating hydraulic impulses, an increase in rock permeability and an acceleration of water inflow into the well. At the same time, by linking the borehole system with an intermediate trunk, and laying an ascending well with an obliquely cased filter column, the volume coverage of the thermal horizon is provided, increasing the uninterrupted operation period, where the circulation channel from the lower ledge to the entrance to the tank with smoothly bending joints is made with one diameter. This eliminates local pressure losses. By grinding the wall of the intermediate shaft with rock hardening, water leaks and pressure losses along the length of the circulation channel are eliminated. The significance of the circulation scheme – the extraction of hot water is carried out by forced self-discharge, without attracting energy from outside.

MODELING THE KINEMATICS AND DYNAMICS OF UNIVERSAL JOINT

The universal joint or Hooke joint, or U-joint is the main unit of the cardan transmission, which consists of two joints connected by an intermediate shaft. Cardan gears are widely used in various industries when creating machines with power transfer from the output shaft of the gearbox to the crank shaft in the absence of their coaxiality. A sufficiently large number of works are devoted to the study of the kinematics of the universal joint, and there are no works on its dynamics. Such a description became possible due to the use of matrix and quaternion formalism in describing the movement of the universal joint. In this paper, a complete description of the kinematics of the universal joint in its working cycle in terms of analogues of angular velocities is obtained and, on this basis, the dynamics of the joint is studied, taking into account its inertial characteristics. It is shown that taking into account the inertial characteristics of the U-joint cross can lead to a significant increase in the magnitude of the torque, the effectiveness on the spikes, in contact with the fork of the driven shaft.

Investigation of the heavy duty truck gear drive failure

For heavy vehicle systems, within the power transmission chain from the driving machine to the working components (wheels), gears have a large share of application in the form of gearboxes, differentials and speed reducers. Their purpose is to achieve the highest possible output torque at the working components. In one heavy-duty truck, the gearbox lost its working capacity due to the failure of its vital parts: a tapered roller bearing and a helical gear. The analysis presented in this paper, conducted on the basis of experimental and analytical methods, showed that, due to inadequate installation of the bearings’ outer ring in the gearbox housing in one intermediate shaft support, the roller bearing performed its elementary function in very unfavorable working conditions of mechanical and thermal nature. Due to the damage accumulation, the roller bearing gradually lost its working capacity. As a result, the intensity of the working conditions of the entire gearbox increased. At the moment when they reached the critical value from the aspect of the gear teeth bending strength, volumetric destruction occurred, i.e fracture of the helical gear tooth, and thus the cessation of gearbox power transmission.

Digital Twin Based Virtual Sensor for Online Fatigue Damage Monitoring in Offshore Wind Turbine Drivetrains

Abstract In this article a virtual sensor for online load monitoring and subsequent remaining useful life (RUL) assessment of wind turbine gearbox bearings is presented. Utilizing a Digital Twin framework the virtual sensor combines data from readily available sensors of the condition monitoring (CMS) and supervisory control and data acquisition (SCADA) system with a physics-based gearbox model. Different state estimation methods including Kalman filter, Least-square estimator, and a quasi-static approach are employed for load estimation. For RUL assessment the accumulated fatigue damage is calculated with the Palmgren–Miner model. A case study using simulation measurements from a high-fidelity gearbox model is conducted to evaluate the proposed method. Estimated loads at the considered intermediate and high-speed shaft bearings show moderate to high correlation (R = 0.50 − 0.96) to measurements, as lower frequency internal dynamics are not fully captured. The estimated fatigue damage differs by 5–15% from measurements.

Экономическая эффективность разработки системы диагностики судового валопровода

The ship shafting ensures the operation of power plants for a significant number of ships of the Russian fleet. Improving the methods of increasing its reliability is an important and urgent task. Part of the loads acting on the propeller and intermediate shafts are random in time and magnitude, that is why it becomes necessary to create a diagnostic system to record the loads and assess the technical condition in real time. The project for creating such a system is knowledge-intensive and involves a large amount of R&D and attraction of investments. There has been suggested an approach to substantiate R&D based on the description of its novelty, commercialization prospects, market analysis and segmentation, business model and calculation of planned economic indicators. The results of the statistical analysis of ship shafting failures are given. An approach is proposed to improve the reliability of a ship power plant based on the simultaneous registration of torsional, transverse and longitudinal vibrations. A quantitative assessment of the market volume was carried out, taking into account the volatility of the exchange rate. The total market size is estimated by the number of vessels in operation by using the methodology of PAM, TAM, SAM and SOM indicators. The target audience of the project was determined by available distribution channels. A nine-block model and commercialization scheme have been developed. The results of calculating the economic efficiency of the investment project are given: net present value and internal rate of return. The results obtained and the applied approaches can serve as a basis for substantiating the investment attractiveness of high-tech projects in the shipbuilding industry.