Study on the pin Track of Four-Bar Linkage with Clearances

2011 ◽  
Vol 120 ◽  
pp. 329-334
Author(s):  
Ying Cai Yuan ◽  
Yan Li ◽  
Xin Liu
Keyword(s):  
Mechanical System ◽  
High Speed ◽  
Mechanical Performance ◽  
Kinematics And Dynamics ◽  
Dynamics Model ◽  
The Stability ◽  
Center Track ◽  
Pin Track ◽  
Four Bar Linkage

The pair clearance is inevitably exists in the mechanical system. With the speed of mechanical system increasing, clearance does harm to the stability and precision of mechanical system. Using four-bar linkage as the example to research the clearances’ characters, a dynamics model is established based on the kinematics and dynamics relations of the mechanism. Through the dynamics model, the track of pin center to collar in pair can be gotten. The irregularity of pin center track is related to the clearance and velocity and seriously influences the mechanical performance. So, it has to pay more attention to the clearance, especially in high speed.

ON-LINE PERFORMANCE ASSESSMENT AND FAULT DIAGNOSIS OF MECHANICAL SYSTEMS

2015 ◽  
Vol 39 (3) ◽  
pp. 705-715 ◽  
Author(s):  
Shang-Liang Chen ◽  
Yin-Ting Cheng ◽  
Hsien-Cheng Liu ◽  
Yun-Yao Chen
Keyword(s):  
Fault Diagnosis ◽  
Performance Assessment ◽  
Mechanical System ◽  
High Speed ◽  
Mechanical Performance ◽  
Wavelet Packet ◽  
Principal Component ◽  
Spindle Motor ◽  
Diagnostic Model ◽  
On Line

This study integrates sensors, signal capture equipment, industrial computers and machinery health check-up software to develop an On-line Performance Assessment and Fault Diagnosis of Mechanical System, helping engineers predict mechanical conditions. Physical quantities captured by the sensors is utilized to process physical signals, and the Wavelet Packet Energy method is used for the feature extraction of non-stationary signals in coordination with the Principal Component Analysis for feature selection. This study establishes On-line Performance Assessment and Fault Diagnosis of Mechanical System based on Discriminant Analysis which is able to immediately determine the mechanical performance. When abnormal mechanical conditions occur, Bayesian Network will be activated to construct error diagnostic model and determine possible causes of error or malfunction of the machinery. Finally, the system is applied to the fan motor, high-speed spindle motor and AC motor of the machine tool. Experimental results show that the theory can effectively diagnose mechanical performance remarkable with an accuracy rate of 92.50% or higher.

scholarly journals Improving the Stability of the Passenger Vehicle by Using an Active Stabilizer Bar Controlled by the Fuzzy Method

Complexity ◽  
2021 ◽  
Vol 2021 ◽  
pp. 1-20
Author(s):  
Tuan Anh Nguyen
Keyword(s):  
High Speed ◽  
Control Method ◽  
Spatial Dynamics ◽  
The Body ◽  
Vertical Force ◽  
Dynamics Model ◽  
Track Dynamics ◽  
The Difference ◽  
Lift Off ◽  
The Stability

The rollover phenomenon is a particularly dangerous problem. This phenomenon occurs when the driver travels at high speed and suddenly steers. Under the influence of centrifugal force, the body vehicle will be tilted and cause the wheels to lift off the road. To solve this problem, the method of using an active stabilizer bar has been proposed. The active stabilizer bar is controlled automatically by a previously designed controller. The performance of the active stabilizer bar depends on the selected control method. Previous research often only used a half-car dynamics model combined with a linear single-track dynamics model to simulate the vehicle’s oscillation. In addition, most of the research focuses only on the use of linear control methods for the active stabilizer bar. Therefore, the performance of the stabilizer bar is not guaranteed. This paper focuses on establishing the model of spatial dynamics combined with the nonlinear double-track dynamics model that fully describes the vehicle’s oscillation most accurately. Besides, the fuzzy control method is proposed to control the operation of the hydraulic stabilizer bar. This is a completely novel model, and it is suitable for the actual traveling conditions of the vehicle. Also, simulations are done based on different scenarios. The results of the paper showed that the values of the roll angle, the difference in the vertical force at the wheels, and the displacement of the unsprung mass were significantly reduced when the vehicle used the active stabilizer bar, which is controlled by an intelligent control method. Therefore, the stability and safety of the vehicle have been guaranteed. This result will be the basis for performing other more complex research in the future.

scholarly journals Research on Stress Characteristics of Segment Structure during the Construction of the Large-Diameter Shield Tunnel and Cross-Passage

Symmetry ◽  
2020 ◽  
Vol 12 (8) ◽  
pp. 1246
Author(s):  
Zhongsheng Tan ◽  
Zonglin Li ◽  
Wei Tang ◽  
Xueying Chen ◽  
Junmeng Duan
Keyword(s):  
High Speed ◽  
Mechanical Response ◽  
Mechanical Performance ◽  
Large Diameter ◽  
Bending Moment ◽  
Shield Tunnel ◽  
Railway Network ◽  
Maximum Deformation ◽  
Intercity Railway ◽  
The Stability

With the intensive development of China’s high-speed railway network and intercity railway network, the construction of the large-diameter shield tunnels and cross-passages is gradually increasing. The construction of large diameter shield tunnels and the excavation of cross-passages puts forward higher requirements for the stability and safety of segment structure. Based on the Wangjing tunnel project, this paper studies the segment displacement and mechanical response of the shield tunnel with a diameter of 10.5 m in the process of shield construction and cross-passage construction. The results show that during the construction of large diameter shield tunnels, the vault and invert produce inward displacement, the invert uplift usually is more severe than the vault settlement, and the arch waist on both sides produces outward displacement. Near the segment K (capping block), the mechanical performance of the segment is close to that of the hinge or chain rod, which can only effectively transmit the axial force but cannot resist the bending moment and shear force. During construction of the cross-passage, the maximum deformation and stress of shield tunnel segment are symmetrically located at the interface of the main tunnel and cross-passage. The upper and lower edges of the segment at the interface tend to change from compression to tension. At the same time, the steel bars on the inside and outside of the segment vault and the arch waist change from compressive stress to tensile stress, which can easily lead to segment damage, so these positions can be reinforced by erecting section steel frames before construction.

The Robust Design of Four-Bar Linkage with Clearance Based on Sensitivity Analysis

2010 ◽  
Vol 34-35 ◽  
pp. 1656-1660 ◽  
Author(s):  
Ying Cai Yuan ◽  
Yi Lun Liu ◽  
Yan Li
Keyword(s):  
Sensitivity Analysis ◽  
Mechanical System ◽  
Robust Design ◽  
Optimization Design ◽  
Design Method ◽  
Dynamic Performance ◽  
Nonlinear Dynamic Model ◽  
The Stability ◽  
And Control ◽  
Four Bar Linkage

Clearance is inevitable，so, with the increasing of machine’s speed, nonlinear vibration phenomenon caused by clearance is more apparent, which influences the precision and stability of mechanical system. For increasing the stability of mechanical system, a robust design method based on sensitivity analysis is studied, by using four-bar linkage as the research object, deducing the nonlinear dynamic model with clearance and the sensitivity of dynamic response, based on the rational planning to the tracks and control the sensitivities. In the design example, it shows that although the track deviation of robust design is slightly bigger than that of optimization design, the comprehensive dynamic performance of the mechanical system is much better than the latter, which means the stability of mechanical system is improved greatly. Thus, the robust design based on sensitivity analysis is an effective way to improve the stability of the mechanical system.

RANCANG BANGUN MESIN PEMOTONG RUMPUT TENAGA SURYA UNTUK NAVIGASI

2015 ◽  
Vol 1 (1) ◽  
pp. 5-16
Author(s):  
John Ohoiwutun
Keyword(s):  
High Speed ◽  
Solar Power ◽  
Human Life ◽  
Operating Cost ◽  
Fuel Oil ◽  
Kinematics And Dynamics ◽  
Control Input ◽  
High Speed Cutting ◽  
Lawn Mower ◽  
Coal Fuel

Utilization of conventional energy sources such as coal, fuel oil, natural gas and others on the one hand has a low operating cost, but on the other side of the barriers is the greater source of diminishing returns and, more importantly, the emergence of environmental pollution problems dangerous to human life. This study aims to formulate the kinematics and dynamics to determine the movement of Solar Power Mower. In this study, using solar power as an energy source to charge the battery which then runs the robot. Design and research was conducted in the Department of Mechanical Workshop Faculty of Engineering, University of Hasanuddin of Gowa. Control system used is a manual system using radio wave transmitter and receiver which in turn drive the robot in the direction intended. Experimental results showed that treatment with three variations of the speed of 6.63 m / s, 8.84 m / s and 15.89 m / sec then obtained the best results occur in grass cutting 15.89 sec and high-speed cutting grass 5 cm. Formulation of kinematics and dynamics for lawn mowers, there are 2 control input variables, x and y ̇ ̇ 3 to control the output variables x, y and θ so that there is one variable redudant. Keywords: mobile robots, lawn mower, solar power

A Statistical Study of Process Variables to Optimize a High Speed Curtain Coater: Part I

TAPPI Journal ◽  
2009 ◽  
Vol 8 (1) ◽  
pp. 20-26 ◽  
Author(s):  
PEEYUSH TRIPATHI ◽  
MARGARET JOYCE ◽  
PAUL D. FLEMING ◽  
MASAHIRO SUGIHARA
Keyword(s):  
Boundary Layer ◽  
Experimental Design ◽  
High Speed ◽  
Statistical Study ◽  
Process Variables ◽  
High Speeds ◽  
The Stability ◽  
Air Removal ◽  
Removal System

Using an experimental design approach, researchers altered process parameters and material prop-erties to stabilize the curtain of a pilot curtain coater at high speeds. Part I of this paper identifies the four significant variables that influence curtain stability. The boundary layer air removal system was critical to the stability of the curtain and base sheet roughness was found to be very important. A shear thinning coating rheology and higher curtain heights improved the curtain stability at high speeds. The sizing of the base sheet affected coverage and cur-tain stability because of its effect on base sheet wettability. The role of surfactant was inconclusive. Part II of this paper will report on further optimization of curtain stability with these four variables using a D-optimal partial-facto-rial design.

LANDSLIDE RISK MANAGEMENT IN THE COASTAL ZONE OF THE KUIBYSHEV RESERVOIR DUE THE DESIGN OF HIGH-SPEED LINE "MOSCOW-KAZAN"

2017 ◽  
Author(s):  
Nikolai Petrov ◽  
Nikolai Petrov ◽  
Inna Nikonorova ◽  
Inna Nikonorova ◽  
Vladimir Mashin ◽  
...  
Keyword(s):  
High Speed ◽  
Computational Models ◽  
Stable State ◽  
Landslide Risk ◽  
Kuibyshev Reservoir ◽  
Stepped Surface ◽  
The Stability ◽  
Landslide Slope ◽  
The Village

High-speed railway "Moscow-Kazan" by the draft crosses the Volga (Kuibyshev reservoir) in Chuvashia region 500 m below the village of New Kushnikovo. The crossing plot is a right-bank landslide slope with a stepped surface. Its height is 80 m; the slope steepness -15-16o. The authors should assess the risk of landslides and recommend anti-landslide measures to ensure the safety of the future bridge. For this landslide factors have been analyzed, slope stability assessment has been performed and recommendations have been suggested. The role of the following factors have been analyzed: 1) hydrologic - erosion and abrasion reservoir and runoff role; 2) lithologyc (the presence of Urzhum and Northern Dvina horizons of plastically deformable rocks, displacement areas); 3) hydrogeological (the role of perched, ground and interstratal water); 4) geomorphological (presence of the elemental composition of sliding systems and their structure in the relief); 5) exogeodynamic (cycles and stages of landslide systems development, mechanisms and relationship between landslide tiers of different generations and blocks contained in tiers). As a result 6-7 computational models at each of the three engineering-geological sections were made. The stability was evaluated by the method “of the leaning slope”. It is proved that the slope is in a very stable state and requires the following measures: 1) unloading (truncation) of active heads blocks of landslide tiers) and the edge of the plateau, 2) regulation of the surface and groundwater flow, 3) concrete dam, if necessary.

Dynamic Performance of High-Speed Electric Multiple Unit within Multi-Body System Simulation

2019 ◽  
Vol 12 (4) ◽  
pp. 339-349
Author(s):  
Junguo Wang ◽  
Daoping Gong ◽  
Rui Sun ◽  
Yongxiang Zhao
Keyword(s):  
High Speed ◽  
Rapid Development ◽  
Dynamic Performance ◽  
Body System ◽  
High Speed Railway ◽  
Evaluation Indexes ◽  
Actual Operation ◽  
Multiple Unit ◽  
The Stability ◽  
Multi Body

Background: With the rapid development of the high-speed railway, the dynamic performance such as running stability and safety of the high-speed train is increasingly important. This paper focuses on the dynamic performance of high-speed Electric Multiple Unit (EMU), especially the dynamic characteristics of the bogie frame and car body. Various patents have been discussed in this article. Objective: To develop the Multi-Body System (MBS) model of EMU, verify whether the dynamic performance meets the actual operation requirements, and provide some useful information for dynamics and structural design of the proposed EMU. Methods: According to the technical characteristics of a typical EMU, a MBS model is established via SIMPACK, and the measured data of China high-speed railway is taken as the excitation of track random irregularity. To test the dynamic performance of the EMU, including the stability and safety, some evaluation indexes such as wheel-axle lateral forces, wheel-axle lateral vertical forces, derailment coefficients and wheel unloading rates are also calculated and analyzed in detail. Results: The MBS model of EMU has better dynamic performance especially curving performance, and some evaluation indexes of the stability and safety have also reached China’s high-speed railway standards. Conclusion: The effectiveness of the proposed MBS model is verified, and the dynamic performance of the MBS model can meet the design requirements of high-speed EMU.

scholarly journals Mechanical Performance of a Ballastless Track System for the Railway Bridges of High-Speed Lines: Experimental and Numerical Study under Thermal Loading

Materials ◽  
2021 ◽  
Vol 14 (11) ◽  
pp. 2876
Author(s):  
Yingying Zhang ◽  
Lingyu Zhou ◽  
Akim D. Mahunon ◽  
Guangchao Zhang ◽  
Xiusheng Peng ◽  
...  
Keyword(s):  
High Speed ◽  
Thermal Loading ◽  
Mechanical Performance ◽  
Track Structure ◽  
Box Girder ◽  
High Speed Railway ◽  
Ballastless Track ◽  
Track System ◽  
Girder Bridge ◽  
Track Slab

The mechanical performance of China Railway Track System type II (CRTS II) ballastless track suitable for High-Speed Railway (HSR) bridges is investigated in this project by testing a one-quarter-scaled three-span specimen under thermal loading. Stress analysis was performed both experimentally and numerically, via finite-element modeling in the latter case. The results showed that strains in the track slab, in the cement-emulsified asphalt (CA) mortar and in the track bed, increased nonlinearly with the temperature increase. In the longitudinal direction, the zero-displacement section between the track slab and the track bed was close to the 1/8L section of the beam, while the zero-displacement section between the track slab and the box girder bridge was close to the 3/8L section. The maximum values of the relative vertical displacement between the track bed and the bridge structure occurred in the section at three-quarters of the span. Numerical analysis showed that the lower the temperature, the larger the tensile stresses occurring in the different layers of the track structure, whereas the higher the temperature, the higher the relative displacement between the track system and the box girder bridge. Consequently, quantifying the stresses in the various components of the track structure resulting from sudden temperature drops and evaluating the relative displacements between the rails and the track bed resulting from high-temperature are helpful in the design of ballastless track structures for high-speed railway lines.

scholarly journals Influence of Whey Protein Micro-Gel Particles and Whey Protein Micro-Gel Particles-Xanthan Gum Complexes on the Stability of O/W Emulsions

Polymers ◽  
2021 ◽  
Vol 13 (14) ◽  
pp. 2301
Author(s):  
Man Zhang ◽  
Bin Liang ◽  
Hongjun He ◽  
Changjian Ji ◽  
Tingting Cui ◽  
...  
Keyword(s):  
Oxidative Stability ◽  
Whey Protein ◽  
High Speed ◽  
Xanthan Gum ◽  
Physical Stability ◽  
Theoretical Support ◽  
Gel Particles ◽  
Oil In Water ◽  
The Stability ◽  
The Impact

Appropriate pretreatment of proteins and addition of xanthan gum (XG) has the potential to improve the stability of oil-in-water (O/W) emulsions. However, the factors that regulate the enhancement and the mechanism are still not clear, which restricts the realization of improving the emulsion stability by directional design of its structure. Therefore, the effects of whey protein micro-gel particles (WPMPs) and WPMPs-XG complexes on the stability of O/W emulsion were investigated in this article to provide theoretical support. WPMPs with different structures were prepared by pretreatment (controlled high-speed shear treatment of heat-set WPC gels) at pH 3.5–8.5. The impact of initial WPC structure and XG addition on Turbiscan Indexes, mean droplet size and the peroxide values of O/W emulsions was investigated. The results indicate that WPMPs and XG can respectively inhibit droplet coalescence and gravitational separation to improve the physical stability of WPC-stabilized O/W emulsions. The pretreatment significantly enhanced the oxidative stability of WPC-stabilized O/W emulsions. The addition of XG did not necessarily enhance the oxidative stability of O/W emulsions. Whether the oxidative stability of the O/W emulsion with XG is increased or decreased depends on the interface structure of the protein-XG complex. This study has significant implications for the development of novel structures containing lipid phases that are susceptible to oxidation.

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