Performance Of Gearbox Research Articles

Convformer-NSE: A Novel End-to-End Gearbox Fault Diagnosis Framework Under Heavy Noise Using Joint Global and Local Information

The application of convolutional neural network (CNN) has greatly promoted the scope and scenario of intelligent fault diagnosis and brought about a significant improvement of intelligent model performance. Solving the feature extraction and fault diagnosis of machinery with heavy noise is beneficial for stable industrial production. However, the local properties of CNN prevent it from obtaining global features to collect sufficient fault information, leading to the degradation of fault diagnosis performance of CNN under heavy noise. In this article, a novel framework named Convformer-NSE is developed to extract robust features that integrate both global and local information, aiming at improving the end-to-end fault diagnostic performance of gearbox under heavy noise. First, Convformer is constructed to improve the nonlinear representation of the feature map, in which the sparse modified multi self-attention is used to model the long-range dependency of the feature map while keeping attention on local features. Then, the extracted spatial features at various scales are fused and fed in the designed novel Senet (NSE) for channel adaptivity learning. The Convformer-NSE is used for the analysis of raw vibration data of different gearbox systems. The experimental signal analyses demonstrate that our developed framework is superior to others.

A Preliminary Experimental Study on the Effects of Wear on the Torsional Stiffness of Strain Wave Gears

Strain wave gears, also known as harmonic drives, are employed in a wide range of fields such as robotics and aerospace, where light weights, precision, and reliability are essential to the correct execution of the tasks. For this reason, their understanding and optimization are of high interest for both academia and industry. Previous studies have been mainly focused on investigating and modeling the working principle of strain wave gears in nominal operating conditions. On the contrary, the present paper describes the results of an experimental campaign aimed to introduce wear in gears of two different suppliers and its impact on the gear torsional stiffness. Results show how the change in the gear performance strongly depends both on the gear manufacturer and the location of wear. For the analyzed components, a damaged wave generator–flexspline interface reduces the gear stiffness up to one-fourth of its nominal value, while the non-nominal shape of the teeth jeopardizes the gearbox performance, leading up to just 4% of the nominal stiffness values, and resulting in backlash. Such data can be used to properly model the presence of wear in strain wave gears and to train data-driven diagnostics and prognostics routines to effectively detect such a fault.

Investigation of Tribological Properties of TiO2, MoS2 and CaF2 Particles as Vegetable Oil Additives and Their Effects on Gearbox Performance

Investigation of Tribological Properties of TiO2, MoS2 and CaF2 Particles as Vegetable Oil Additives and Their Effects on Gearbox Performance

A Review on Design and Efficiency Improvement of Worm and Worm Wheel of a Gear Motor

Geometry and operating standards determines that worm drives are critical components in and of applications within the power transmission industry. In one reduction point, it is used in large drive ratios with compact assembly dimensions. Worm and worm wheels are provided with a quiet operation owing to the movement of slipping between the worm and worm wheels tooth flanks. Its efficiency depends significantly on the thickness of the lubricating film, which in turn is dependent on various operating parameters. The different researchers have performed detailed research in the field of worm and worm wheel construction. Many researchers have developed and suggested methods for the prediction of worm and worm wheel gearbox performance with respect to different factors such as tribology, analytic and geometry. This paper includes a comprehensive literary analysis to obtain thorough knowledge of trends in the fields of worm and worm gears.

Comparative Investigation of Worm Positions for Worm Gear-box Performance under No-Load Condition

The Worm Gear drive is a gear arrangement where the worm shaft meshes with a worm wheel (gear). The worm shaft plays an important role in reduction ratio & efficiency. This worm shaft can be used at the top and the bottom in the gearbox. This technical research paper provides a comprehensive comparative evaluation of Input torque analysis & heating rate of lubricant inside the gearbox for two positions of the worm shaft in the worm gearbox under no-load condition. Worm shaft at the top and worm shaft at the bottom were assessed at variable speed (1000-1400 rpm), the different splashed volume of lubricant (1.5-2.7 liter), and variable temperature of lubricant (30-50 ºC). Input torque was measured with the help of a direct torque measurement technique. Similarly, the heating rate of the lubricant was also measured with a temperature sensor for both orientations of the worm shaft. Full factorial experiments were performed on a specially designed and fabricated worm gear test rig. The experiments showed that the input torque requirement for the worm at the bottom position is 20 -25% higher than the worm at the top position at an average speed. The heating rate remains almost the same for both orientations. This study aimed to find the suitable orientation of the worm shaft which reduces the power losses and increases efficiency.

WITHDRAWN: Optimization of process parameters by Hybrid Taguchi-Grey Relational Analysis for thermal behaviours of lubricant oil of worm gearbox

In this research work, the major focus is given on thermal behaviours of lubricant oil of worm gearbox. In worm gearbox due to sliding motion between teeth's of worm and worm wheel cause friction energy loss. The friction energy loss is converted into heat energy and that heat energy is dissipated into lubricant oil of worm gearbox. The performance of lubricant oil is decreasing due to the rise in temperature which causes decreases in the overall performance of gearbox. To observe thermal behaviour of lubricant oil of worm gearbox Lubricant Heating Time (time required to increase the temperature of the oil from 35 °C to 50 °C) and the Viscosity of oil (at 50 °C) is taken as response parameters while Load on the worm wheel (L), Volume of oil (V) and Type of oil (T) are taken as process parameters. Every process parameter is varied at three dissimilar levels. Taguchi optimization technique (L9) is used for the optimization of experiments for this Minitab19 software is used. Grey Relational Analysis (GRA) is used to determine the optimum levels of process parameters. The optimum levels of process parameters for maximum Lubricant Heating Time and maximum Viscosity are L1V2T2 i.e. the lowest level of Load on the worm wheel, intermediate level of Volume of oil and Type of oil B. ANOVA is performed to determine the relative contribution of process parameters on Lubricant Heating Time. ANOVA results show that Type of oil is the maximum influence parameter (98.26%) followed by Load on the worm wheel (0.99%) and Volume of oil (0.72%) on Lubricant Heating Time. There exist an inverse relationship between oil viscosity and lubricant heating time.

Dynamic failure analysis of renewable energy systems in the remote offshore environments

AbstractFor effective integrity management of marine renewable energy systems in the dynamic and uncertain ocean environments, understanding the failure dynamics is crucial. The cost of investment in marine/offshore renewable energy infrastructures and the associated cost due to failure and loss of energy production necessitate a predictive monitoring methodology that is dynamic and adaptive. This paper presents an integrated multi‐state pure‐birth‐pure‐death Markovian‐net profit value model for the offshore turbine subsystem failure analysis and its cost‐based consequences. The integrated model captures the offshore turbine subsystem's dynamic failure states and its economic implications due to the cost of energy loss and downtime for the period under consideration. The model applies a phase‐type exponential distribution to describe the monotonic state of failure. The methodology is demonstrated with an offshore wind turbine gearbox, and it captures the dynamic state of the system and its failure mechanisms. The cumulative effect of the subelements deterioration decreases the gearbox performance by over 35% within the first 2 years of operation.

MODEL PREDICTIVE CONTROL OF A HYDRAULIC ACTUATOR IN TORQUE APPLYING SYSTEM OF A MECHANICALLY CLOSED-LOOP TEST RIG FOR THE HELICOPTER GEARBOX

Transmission health is an important factor in safety and maintenance costs in industries, so construction of test rigs for testing high-powered gearboxes under different operating conditions of helicopters is required. The studied test rig, which is developed at Sharif University of Technology branch of ACECR (Academic Centre of Education, Culture and Research) is mainly used for testing high-powered gearboxes through a mechanically closed-loop procedure. For providing a variety of speeds and torques in test rigs, torque applying system is required. According to generation of higher forces, reduced size of equipment and accurate positioning, electro hydraulic actuators (EHAs) are used for applying torques for planetary gearboxes of this test rig. Due to the importance of applying accurate torques in evaluation of the gearbox performance, first an accurate model of EHA is derived, which captures the system dynamics using system identification method with low consumed time and simple relations. After that, a type of model predictive controller called dynamic matrix controller is proposed for controlling EHA under determined requirements. Then, the performance of proposed controller under normal conditions as well as in presence of disturbance is investigated. The results show a good tracking of controller for various reference inputs in different conditions. Moreover, the performance of the proposed controller is compared with the performance of classical proportional-integral-derivative (PID) controller and superior characteristics of the proposed controller is concluded.

A Fuzzy Performance Evaluation Model for a Gearbox System Using Hidden Markov Model

In order to track and grasp the operation situations of the gearboxes, the vertical vibration signals of three different gear fault states, normal, worn and broken teeth, are collected via a gearbox vibration experiment. An online diagnosis and performance evaluation model with hidden Markov model (HMM) and fuzzy comprehensive evaluation is proposed. To address the limitation of maximum membership principle in the case of equal membership or the membership is very close to each other, a closeness evaluation strategy is proposed by defining the likelihood ratio of HMM as a similarity and selecting an combined membership function of the semi-trapezoidal and intermediate-ridge distribution. Results show that the online diagnosis has achieved a good performance with the similarity strategy. Compared with the evaluation strategy of the maximum membership principle, the proposed gearbox performance model with the closeness evaluation strategy is more accurately distinguished from the evaluation results of the broken teeth state and the worn state, especially for the case of the equal membership.

Topology optimization of Workbench gearbox Box reinforced bar based on ANSYS

In order to improve the structural performance of gearbox and improve the service life of gearbox, a method based on topology optimization to improve the layout of reinforcement is proposed in this paper. In this paper, a three-dimensional model of gearbox is established in CREO3.0, and the simulation analysis is carried out by using ANSYS Workbench software to optimize the layout of stiffeners and obtain the best scheme.The results before and after optimization are compared and analyzed, and it can be seen that there is a reduction in stress concentration after optimization.

Digital Modeling and Testing of Tractor Characteristics

A kinematic model of the gearbox and a simplified kinematic model of a tractor are developed. These models take account of the characteristics of the internal-combustion engine employed, corresponding to the customer requirements on gearbox performance. Virtual tests of the tractor establish the tractional and dynamic characteristics of the tractor and its tractional class according to State Standards GOST 27021–86 and GOST 30745–2001 (ISO 789-9–90).

Experimental Investigation to Enhance the Performance of High Speed Reduction Gearbox using Nano Blended Lubricants

The sliding motion between worm and worm wheel is the inherent factor that makes the worm and worm wheel drives less efficient among all the gear drives. Efficiency of these gears varies between 40 to 90%. They need good lubricants, which has high heat dissipation capacity and low coefficient of friction for improving the efficiency. The lubricants considered in the current investigation play a significant role in decreasing the power losses in gearbox besides the geometry of the gears. Nano blended lubricants are found to have efficient tribological and thermal physical properties such as, less frictional coefficient and high heat transfer coefficient. Al2O3 Nano particles of 30 nm size dispersed in SAE 140 mineral oil at different volume fractions resulted decrease in frictional coefficient and found varying from 0.1 to 0.5% nano particle volume fractions. Further, heat transfer coefficient is enhanced by 46.35% for volume fraction of 0.5% and also temperature rise of nano blended lubricant was found to be less than that of base lubricant. The overall efficiency of the selected gearbox with which the experimentation has been done was found to be increased with usage of nano blended lubricant. The performance of the gearbox using nano lubricant at 0.5 volume percent is found improved by 4.85 and 7.86% at operating temperatures 35 and 60oC, respectively compared to the performance of the gearbox using base lubricant.

Experimental investigation on interaction of wave disk generator with flexible gear

AnnotationPower processes that proceed upon interaction between the flexible gear and the wave disk generator were investigated. Experimental values of the normal load q distribution in an area of the flexible gear contact with the wave generator disks were determined. This load was applied to the flexible gear on the side of the wave generator disks (from the principal axis φ of the wave gearing) and selected for various torque M2 values being transmitted. Moreover, a dependence of the resultant force R, impressed by the flexible gear to the wave generator disks, on the torque M2 values was determined. An experimental investigation under conditions of the heavy engineering has been scheduled. A wave gearing built in the Type VZ-1120 Gearbox of the MP-600AS torpedo car swivel mechanism was used as the prototype. It was investigated on a universal test stand with an opened power loop. Investigation results obtained in such a way are used in heavy engineering as the guiding data for performance of the development and design engineering works and optimization of the heavy wave gearbox performance.

PERANCANGAN GEARBOX TRAKTOR TANGAN 2 KECEPATAN 1 MUNDUR DENGAN SISTEM PEMINDAH GIGI SYNCHROMESH

Abstrak
 
 Saat ini Polman Bandung sedang melakukan pengembangan hand tractor atau traktor tangan melalui Pusat Pengembangan Power Train Otomotif (P3TO) dengan fokus kajian yang penting untuk dilakukan saat ini adalah perancangan gearbox baru untuk traktor tangan yang akan dikembangkan. Pengembangan-pengembangan yang akan dilakukan saat ini ialah penambahan kecepatan pada gearbox, peningkatan perfoma gearbox dan peningkatan kemudahan operasi dari gearbox yang dilihat dari segi sistem pemindah gigi yang ada pada gearbox. Hal ini didasarkan pada model-model gearbox pada traktor tangan yang ada di Indonesia, dinilai memiliki kekurangan pada aspek-aspek yang akan dikembangkan saat ini terutama pada jumlah kecepatan dan sistem pemindah giginya, maka dari itu pada tugas akhir ini dipilih multi speed gearbox dengan 2 kecepatan 1 mundur dengan sistem pemindah gigi synchromesh untuk mengatasi kekurangan-kekurangan gearbox traktor tangan yang ada saat ini. Tahapan perancangan dilakukan berdasarkan metode perancangan VDI 2222. Penelitian ini bertujuan untuk menghasilkan rancangan gearbox yang sesuai dengan daftar tuntutan dengan sistem dan performa yang lebih baik dari yang ada saat ini di pasaran.

FEA Simulation Based Performance Study of Multi Speed Transmission Gearbox

The main objective of this research work is to investigate the performance of automobile transmission gearbox under the influence of thermal properties variation of gearbox lubricant. An assumption has been made that the air-gear oil mist within transmission is under steady state condition, in isothermal equilibrium with the transmission gear oil bath of lubricant. The lubrication in multi speed transmission is subjected to thermo-elastohydrodynamic lubrication. The study here analyzed transmission in second gear pair. In full torque loading condition the high temperature generated due to meshing action of gears and frictional conditions between the transmission gear train changes the thermo-physical property of gear oil. The overall vehicle transmission gearbox performance is governed by the gear oil properties and it also effects the fuel consumption. This research study was performed at two higher different temperature range of gear oil.The analysis result shows that the gearbox oil thermal properties directly effect the performance and life span of automobile transmission gearbox.

Analysis of Shock Resistance on GWC6066 Marine Gearbox

The dynamic finite element model of entire gearbox, including gears, shafts, bearings and gearbox housing was established by using the truss element, spring element and tetrahedral element at first. Then the shock spectrum of GWC6066 gearbox was gotten according to German specification BV043/85. After the shock spectrum converted into equivalent time-domain acceleration curve, the vibration velocity, vibration acceleration and dynamic stress of GWC6066 gearbox under the double half-sine acceleration shock excitation were simulated. At last, the shock resistance performance of gearbox was analyzed combining with the strength criterion.

Topology Optimization Design of Gearbox Housing in Electric Bus

The virtual prototyping technology in corporation with a finite element analysis was first used to analyze the strength and stiffness of gearbox casing in an electric bus. On the basis of this analysis, the topology optimization technology (TOT) based on the variable density method was introduced into the design of gearbox casing which takes the minimized total flexibility of gearbox as the objective function, the density of each cell as the design variable and the volume as the design constraint. Then, according to the results of topology optimization and the requirements of manufacturing process, the structure of gearbox casing was designed in detail. Finally, the stress analysis of the housing model of the final design was carried out. The results show that the optimized housing not only meets the design requirements of stiffness and strength, but also reduces its quality, which can make the performance of gearbox achieve optimal.

Shock Response Analysis of Marine Gearbox

The shock spectrum of gearbox was gotten according to German specification. And the equivalent time-domain acceleration curve was converted from shock spectrum. After the dynamic finite element model of entire gearbox was established by using the truss element, spring element and tetrahedral element, the shock response including the vibration velocity, acceleration and dynamic stress of gearbox subjected to the acceleration shock excitation were simulated. At last, the anti-shock performance of gearbox was analyzed combining with the strength criterion.

The Performance Analysis and Prognosis Techniques of Gearbox

Under the situation of increasingly stringent requirements for production speed and quality, gearboxes in many manufacturing equipment production lines lose final processing quality after long-term severe service.Machine fault prognosis is for experts or on-site maintenance personnel to use measurement equipment to capture signals and conduct diagnosis and maintenance based on personal experience. As technologies are advancing rapidly and equipment is evolving with increasing level of scale, automation and complexity, traditional diagnostic methods are no longer applicable. The article aims at vibration signal of gearbox to establish analysis and prognosis techniques. Principal components analysis is utilized to effectively capture the characteristic signal. Logistic regression and autoregressive moving average models are utilized to establish the correlation between characteristic signal and gearbox health status and performance trend model for on-site maintenance personnel to instantly understand gearbox health status and potential problems.In addition, Self-organizing map is utilized to establish fault identification model for maintenance personnel to significantly reduce troubleshooting time. In the article, gear-rotor experiment platform is used to assess the feasibility of gearbox performance analysis and prognosis techniques. It is expected to provide gearbox makers and users with understanding of gearbox health status and total solutions.

Optimizing the Performance Evaluation of Robotic Arms with the Aid of Genetic Algorithm

In recent decades, the robotic system is becoming more and more significant and this leads the humans to perform precarious tasks at secure distances. In this paper, we planned to improve the performance of robotic gear box. Like our human hand, the robot hands are utilized for performing various tasks. To facilitate the task, flexible robotic arms is necessary to improve the performance of robotic arm gear box. In existing research, only static parameters were considered to make the robotic arms as flexible but such parameter itself is not enough to obtain the optimized value for the gear box to perform. In order to attain the optimized value for the robotic arm gear box, we considered both dynamic and static parameters. By using such parameter values, the optimized value for the gear box is obtained, which result in better gear box performance. Thus, our proposed work fills the gap occurs in the existing works and this paves the way for obtaining flexible robotic arms. Our result obtained by considering various parameters has shown better performance than the existing works.