scholarly journals Analysis of the Torque Loss of High-Speed Transmission Mechanism with a Stacked Roller Set

Machines ◽  
2021 ◽  
Vol 9 (8) ◽  
pp. 140
Author(s):  
Ke Zhu ◽  
Chuantan Ruan ◽  
Heyuan Wang ◽  
Sheng Li ◽  
Jian Ruan
Keyword(s):  
Mathematical Model ◽  
Rotational Speed ◽  
High Speed ◽  
Theoretical Data ◽  
Transmission Mechanism ◽  
Inertia Force ◽  
Load Pressure ◽  
Enveloping Surface ◽  
Torque Loss ◽  
The Mathematical Model

Two-dimensional pumps have broad application prospects in aerospace. However, the performance of the pump is degraded because of the clearance problem of the current 2D transmission mechanism. In order to eliminate the clearance between the cam rail and the rollers, a high-speed transmission mechanism with a stacked roller set is proposed. The stacked roller set is compressed by the load pressure. The axial inertia force is balanced when the transmission mechanism works at high speed, via the equal acceleration and reverse movement of two cam rail sets. Thus, the transmission mechanism meets the high-speed demand. In this paper, the mathematical model of the transmission mechanism is established based on the enveloping surface theory and the differential geometry principle. Afterwards, numerical analysis of the mathematical model is performed based on MATLAB, combined with the experiment, to study the influence of load pressure and rotational speed on the torque loss. Then, the torque characteristics of the transmission mechanism is obtained. According to a test, the deviation between theoretical data and experimental data is 11.9%; therefore, the mathematical model can predict the torque of the transmission mechanism effectively. It is concluded that the torque loss of the transmission mechanism increases linearly with the load pressure, and the rotational speed has a slight effect on the torque loss.

scholarly journals Research on the Volumetric Efficiency of 2D Piston Pumps with a Balanced Force

Energies ◽  
2020 ◽  
Vol 13 (18) ◽  
pp. 4796
Author(s):  
Yu Huang ◽  
Jian Ruan ◽  
Yong Chen ◽  
Chuan Ding ◽  
Sheng Li
Keyword(s):  
Mathematical Model ◽  
Rotational Speed ◽  
Sliding Friction ◽  
Friction Pair ◽  
Weight Ratio ◽  
Volumetric Efficiency ◽  
Load Pressure ◽  
Axial Piston Pumps ◽  
Working Principle ◽  
The Mathematical Model

Axial piston pumps with high rotational speeds are required in many fields to increase the power-to-weight ratio. However, three main sliding friction pairs in the pump restrict the increase in rotational speed. To solve this problem, we propose a 2D piston pump with a balanced force that contains a sliding friction pair. Firstly, the mechanical structure and working principle of the pump are described. Then, the pump volumetric efficiency is studied by mathematical modeling, and volumetric losses containing backflow and leakage are analyzed and discussed from the perspectives of load pressure and rotational speed. A test bench that verifies the mathematical model is built to measure the volumetric efficiency of the tested pump. We have found that the increase in rotational speed can help to increase the pump volumetric efficiency, and the mathematical model is consistent with the tested data for 1000 rpm but demonstrates a remarkable difference from the tested data for 3000 rpm. Thus, the temperature field of the pump and the viscosity-temperature characteristics of the oil must be taken into account to increase volumetric efficiency further.

scholarly journals A Pot-Like Vibrational Microfluidic Rotational Motor

Micromachines ◽  
2021 ◽  
Vol 12 (2) ◽  
pp. 177
Author(s):  
Suzana Uran ◽  
Matjaž Malok ◽  
Božidar Bratina ◽  
Riko Šafarič
Keyword(s):  
Mathematical Model ◽  
Rotational Speed ◽  
Mechanical Energy ◽  
Real Life ◽  
Frequency Region ◽  
Theoretical Research ◽  
Practical Challenge ◽  
The Mathematical Model ◽  
Motor Structure ◽  
Proper Balance

Constructing a micro-sized microfluidic motor always involves the problem of how to transfer the mechanical energy out of the motor. The paper presents several experiments with pot-like microfluidic rotational motor structures driven by two perpendicular sine and cosine vibrations with amplitudes around 10 μm in the frequency region from 200 Hz to 500 Hz. The extensive theoretical research based on the mathematical model of the liquid streaming in a pot-like structure was the base for the successful real-life laboratory application of a microfluidic rotational motor. The final microfluidic motor structure allowed transferring the rotational mechanical energy out of the motor with a central axis. The main practical challenge of the research was to find the proper balance between the torque, due to friction in the bearings and the motor’s maximal torque. The presented motor, with sizes 1 mm by 0.6 mm, reached the maximal rotational speed in both directions between −15 rad/s to +14 rad/s, with the estimated maximal torque of 0.1 pNm. The measured frequency characteristics of vibration amplitudes and phase angle between the directions of both vibrational amplitudes and rotational speed of the motor rotor against frequency of vibrations, allowed us to understand how to build the pot-like microfluidic rotational motor.

Research on the Performance Simulation of the Transmission System of Loader with Secondary Regulating Technique

2010 ◽  
Vol 426-427 ◽  
pp. 299-302
Author(s):  
Fa Ye Zang
Keyword(s):  
Mathematical Model ◽  
Fuzzy Control ◽  
Energy Saving ◽  
High Speed ◽  
Transmission System ◽  
Performance Simulation ◽  
Constant Torque ◽  
Braking Torque ◽  
The Mathematical Model ◽  
Inertial Energy

Based on deeply analyzing the working principles and energy-saving theory of loader secondary regulating transmission system, regenerating the transmission system’s inertial energy by controlling constant torque was put forward. Considering large changes of the parameters of the transmission system and its non-linearity, a fuzzy control was adopted to control the transmission system, and the mathematical model of the system was established, then the simulations of the performance of the transmission system has been conducted. The conclusion was made that the inertial energy can be reclaimed and reused in the system by the application of the secondary regulation technology, and braking by controlling constant torque is stable, it can ensure the security of braking at high speed and also permits changing the efficiency of recovery by changing the braking torque. The system’s power has been reduced and energy saving has been achieved.

Assessment of roadability and stability of a vehicle movement on the bend

2020 ◽  
Keyword(s):  
Mathematical Model ◽  
Road Surface ◽  
Inertia Force ◽  
Speed Limit ◽  
The Road ◽  
Inertial Moment ◽  
The Mathematical Model ◽  
Computer Imitation ◽  
Vehicle Movement

The paper presents the mathematical model and the technique of computer imitation of a vehicle movement on bend. Research of roadability and stability of the truck and the schedules illustrating change of characteristics of the steered movement have been obtained. The critical modes of the movement causing separation of wheels from road surface and side slippage have been defined. Speed limit of the steered movement on trajectory of the set curvature have been determined. Keywords vehicle, wheel, cross and longitudinal reactions of the road, inertia force, inertial moment, trajectory of a vehicle movement, angles of withdrawal of wheels, spring weight angle of heel, side slippage, vehicle drift

Increasing the mobility of a high-speed tracked vehicle based on a controlled skid algorithm

2020 ◽  
pp. 29-33
Author(s):  
S. V. Kondakov ◽  
O.O. Pavlovskaya ◽  
I.D. Ivanov ◽  
A.R. Ishbulatov
Keyword(s):  
Mathematical Model ◽  
Dynamic Stability ◽  
Simulation Modeling ◽  
Automatic System ◽  
High Speed ◽  
Control Algorithm ◽  
Loss Of Stability ◽  
Tracked Vehicle ◽  
Hydrostatic Transmission ◽  
The Mathematical Model

A method for controlling the curvilinear movement of a high-speed tracked vehicle in a skid without loss of stability is proposed. The mathematical model of the vehicle is refined. With the help of simulation modeling, a control algorithm is worked out when driving in a skid. The effectiveness of vehicle steering at high speed outside the skid is shown. Keywords: controlled skid, dynamic stability, steering pole displacement, hydrostatic transmission, automatic system, fuel supply. [email protected]

scholarly journals The analysis of flutter characteristics based on generalized parameters of eigen modes of vibrations

2021 ◽  
pp. 95-102
Author(s):  
K. I Barinova ◽  
A. V Dolgopolov ◽  
O. A Orlova ◽  
M. A Pronin
Keyword(s):  
Mathematical Model ◽  
High Speed ◽  
Dynamic Pressure ◽  
Mode Shapes ◽  
Scaled Model ◽  
Design Specifications ◽  
Operation Conditions ◽  
Flutter Analysis ◽  
Generalized Parameters ◽  
The Mathematical Model

Flutter numerical analysis of a dynamically scaled model (DSM) of a high aspect ratio wing was performed using experimentally obtained generalized parameters of eigen modes of vibrations. The DSM is made of polymer composite materials and is designed for aeroelastic studies in a high-speed wind tunnel. As a result of the analysis, safe operation conditions (flutter limits) of the DSM were determined. The input data to develop the flutter mathematical model are DSM modal test results, i.e. eigen frequencies, mode shapes, modal damping coefficients, and generalized masses obtained from the experiment. The known methods to determine generalized masses have experimental errors. In this work some of the most practical methods to get generalized masses are used: mechanical loading, quadrature component addition and the complex power method. Errors of the above methods were analyzed, and the most reliable methods were selected for flutter analysis. Comparison was made between the flutter analysis using generalized parameters and a pure theoretical one based on developing the mathematical model from the DSM design specifications. According to the design specifications, the mathematical model utilizes the beam-like schematization of the wing. The analysis was performed for Mach numbers from 0.2 to 0.8 and relative air densities of 0.5, 1, 1.5. Comparison of the two methods showed the difference in critical flutter dynamic pressure no more than 6%, which indicates good prospects of the flutter analysis based on generalized parameters of eigen modes.

scholarly journals Suppression of Ground Borne Vibration Induced by High-Speed Lines

2018 ◽  
Vol 152 ◽  
pp. 02001
Author(s):  
Ali Mohamed Rathiu ◽  
Mohammad Hosseini Fouladi ◽  
Satesh Narayana Namasivayam ◽  
Hasina Mamtaz
Keyword(s):  
Mathematical Model ◽  
Analytical Model ◽  
High Speed ◽  
Moving Load ◽  
Ground Vibration ◽  
Harmonic Excitation ◽  
Vibration Response ◽  
Vibration Velocity ◽  
Velocity Response ◽  
The Mathematical Model

Vibration of high-speed lines leads to annoyance of public and lowering real estate values near the railway lines. This hinders the development of railway infrastructures in urbanised areas. This paper investigates the vibration response of an isolated rail embankment system and modifies the component to better attenuate ground vibration. Mainly velocity response is used to compare the responses and the applied force is of 20 kN at excitation frequencies of 5.6 Hz and 8.3 Hz. Focus was made on ground-borne vibration and between the frequency range of 0 and 250 Hz. 3D Numerical model was made using SolidWork software and frequency response was produced using Harmonic Analysis module from ANSYS Workbench software. For analytical modelling MATLAB was used along with Simulink to verify the mathematical model. This paper also compares the vibration velocity decibels (VdB) of analytical two-degree of freedom model mathematical model with literature data. Harmonic excitation is used on the track to simulate the moving load of train. The results showed that modified analytical model gives the velocity response of 75 VdB at the maximum peak. Changes brought to the mass and spacing of the sleeper and to the thickness and the corresponding stiffness for the ballast does not result in significant vibration response. Limitations of two-degree analytical model is suspected to be the cause of this inactivity. But resonance vibration can be reduced with the aid of damping coefficient of rail pad. Statistical analysis methods t-test and ANOVA single factor test was used verify the values with 95% confidence.

Dynamic Model and Response of Robot Manipulators With Joint Irregularities

1993 ◽  
Vol 115 (1) ◽  
pp. 70-77 ◽  
Author(s):  
R. J. Chang ◽  
T. C. Jiang
Keyword(s):  
Mathematical Model ◽  
Dynamic Model ◽  
High Speed ◽  
Robotic Manipulator ◽  
Irregular Surface ◽  
Positioning Accuracy ◽  
Linearization Methods ◽  
Accuracy And Precision ◽  
Covariance Propagation ◽  
The Mathematical Model

The dynamic equation of a robotic manipulator with joint irregularities is formulated and employed for the prediction of the positioning accuracy and precision of a robotic manipulator in high-speed operation. The mathematical model is derived by incorporating a dynamic model of irregular joints in an ideal robotic equation and employing the Lagrangian formulation. The joint irregularity is modelled as an elastic sliding pair which consists of a journal with an irregular surface sliding on the surface of an elastic bearing. By employing Gaussian linearization methods, the operational accuracy and precision of the robotic manipulator are obtained from mean and covariance propagation equations of the robotic system. The operation of a single-arm robotic manipulator with joint irregularities is investigated for demonstrating the applications of the present techniques.

Optimization of Torsional Dynamic Properties of Hydraulic Excavator Slewing Transmission Mechanism

2012 ◽  
Vol 538-541 ◽  
pp. 2536-2542
Author(s):  
Zhao Jun Li ◽  
Yu Ling Zhang ◽  
Tao Mao ◽  
Xu Juan Yang
Keyword(s):  
Mathematical Model ◽  
Torsional Vibration ◽  
Dynamic Properties ◽  
Optimization Theory ◽  
Moment Of Inertia ◽  
Transmission Mechanism ◽  
Hydraulic Excavator ◽  
Vibration Equation ◽  
Working Device ◽  
The Mathematical Model

A hydraulic excavator is taken as the object to study. Considering the characteristics of slewing transmission mechanism of hydraulic excavator, the torsional vibration equation is established by the finite element method. According to the torsional vibration equation, the effects of the equivalent moment of inertia of working device on the torsional dynamic properties of slewing transmission mechanism are analyzed. Using the optimization theory, the mathematical model is built, which is by means of the equivalent moment of inertia of working device as objective function and by means of the position parameters of the working device as design variables. Based on the mathematical model, the optimization of torsional dynamic properties of slewing transmission mechanism is studied. Finally, a numerical example is presented.

Acoustic response of high-speed deep groove ball bearing by modifying the internal geometry

2020 ◽  
pp. 146441932095511
Author(s):  
Deepak Borse ◽  
VB Tungikar
Keyword(s):  
Mathematical Model ◽  
Contact Stress ◽  
Noise Level ◽  
High Speed ◽  
Ball Bearing ◽  
Experimental Result ◽  
Acoustic Behaviour ◽  
Internal Geometry ◽  
Elliptical Contact ◽  
The Mathematical Model

In this paper, a mathematical model to predict acoustic responses of high-speed bearing has been developed and demonstrated in an application of Induction motors. Effect on the acoustic behaviour of bearing has studied by modifying the internal geometry, such as the number of rotating elements, curvature ratio, rotating speed with the oval shape of the track raceway due to pre-operational damage. The mathematical model predicts the contact stress, elliptical contact area, noise level dB and Frequencies of waviness pattern. High-speed bearing is tested at four different speeds to monitor acoustic behaviour. This drive end bearing undergoes different rotational speeds; however, the author has simulated the results at a majorly driven constant speed. The author has incorporated application-level testing at the customized test rig. The mathematical model has simulated using coupled governing equations with the help of the Ranga-Kutta method. The simulation and experimental results presented in this paper in the form of a waterfall diagram, FFT spectrum and colour pressure plots. Acoustic characteristics during measurements of the rolling bearing have shown systematically to correlate the mathematical model with an experimental result. Results indicate the remarkable influence of raceway nonconformities of bearing on the noise level. The novelty of research study is to estimate the amplitude of noise level due to waviness generated on rings of bearing after pre-operation damage which is the realistic scenario that occurred after a complaint recorded by the motor manufacturer. The authors believe that this technique enables the bearing designer to choose the appropriate diametric ratio of the ball and track curvature for elliptical contact stress as well as acoustic level. This method is developed specifically for an application of drive-end position ball bearing. Practical use of this method is to determine the Noise level of an electric motor (up to 60 kW capacities) due to improper handling and inappropriate installation of bearing which cause inherent waviness on components.

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