The mathematical model and mechanical properties of variable center distance gears based on screw theory

2016 ◽  
Vol 101 ◽  
pp. 116-139 ◽  
Author(s):  
Fangyan Zheng ◽  
Lin Hua ◽  
Xinghui Han
2014 ◽  
Vol 527 ◽  
pp. 140-145
Author(s):  
Da Xu Zhao ◽  
Bai Chen ◽  
Guo Zhong Shou ◽  
Yu Qi Gu

In view of the existing problems of traditional interventional catheters, particularly poor activity, operation difficulty and mass blind area, a novel interventional catheter with a cable-driven active head-end is proposed, and a prototype was built to verify the performance. This paper deals with the kinematics and dynamics of the cable-driven prototype, a dynamic model based on Kanes method combined with screw theory was presented in this paper. According the mathematical model and the prototypes structure, the analysis of kinematics and dynamics of active head-end-end is done in the environment of Mathematica. The needed driving forces of every joint when the system moving along planned trajectory are calculated. The results can provide a basis for the structure design and motion control of the interventional active catheter.


Author(s):  
Yong-Sheng Zhao ◽  
Yu-Lei Hou ◽  
Zhi-Wei Yan ◽  
Hui-Ling Yuan ◽  
Jin Gao

This paper presents the research and design of a novel parallel architecture of pre-stressed six-component force/torque sensor based on the Stewart platform. The mathematical model of the structure was build by using the screw theory. The influence of joint frictional moment on the performances of the sensor is analyzed by using the concept of kinematic influence coefficient. In this paper, we define the indices of force/torque isotropy and generalized amplifying index to evaluate the performances of the sensor and discuss the optimal design of the sensor dimensions considering these indices. The prototype sensor was designed and manufactured. The theoretical and experimental study of the static calibration of the prototype is carried out, and the problem of the hyperstatic is solved perfectly. The results from the static calibration experimentation validate the correctness of the theoretical analysis.


2013 ◽  
Vol 631-632 ◽  
pp. 358-361
Author(s):  
Shang Wei ◽  
Yang Xiao Jing ◽  
Mao Cui ◽  
Guo Long

Polymethyl methacrylate (PMMA) has shown some excellent performances. However the humidity environment affects mechanical properties of PMMA seriously. In this work, the digital phase-shifting photoelasticity is used to test the humidity stress of the boundary according to which we concluded that the boundary stress decreases gradually from the boundary to the inner. The mathematical model of the boundary stress distribution is established based on the distribution law of the boundary stress. This mathematical model can be used to predict the effect of the humidity environment to the boundary stress, and guide PMMA to use safely.


10.12737/8462 ◽  
2015 ◽  
Vol 4 (4) ◽  
pp. 130-139
Author(s):  
Стародубцева ◽  
Tamara Starodubtseva ◽  
Аскомитный ◽  
Aleksey Askomitnyy

This article describes a technique for modeling of wood polymer-sandy composite. Interface input form of initial data for modeling; differential equations underlying the mathematical model are presented. To solve the system of differential and algebraic equations computer program "Program to simulate the struc-ture and mechanical properties of wood polymer-sandy composite" is developed. The program, developed in the environment of Borland Delphi 7.0, programming language Object Pascal, is intended for modeling the mechanical behavior of wood polymer-sandy composite of given composition.


2018 ◽  
Vol 196 ◽  
pp. 04034
Author(s):  
Vakhtang Matua ◽  
Sergey Sizonets ◽  
Dmitry Stroev

Optimization of the proportion and the properties of stabilized macadam and sand mixes (MSM) with introduction of the ANT additive was carried out by means of the mathematical designing of the experiment. This method allows a rather full and comprehensive assessment of the effect of the components on the properties of stabilized macadam and sand mixes (MSM), obtaining of the mathematical model of the process in graphic form, and obtaining of the theoretical model of assessment and prediction of the physical-mechanical and performance properties of the materials under study.At the first stage of the research percentages of a mineral binder, water and an additive were selected and the effect of the variability factor of these components on the mix’s physical-mechanical properties was studied. The following factors were selected as variates: X1 standing for quantity of water, %; X2 standing for the content of sulfate-resistant portland cement grade 500, %; X3 standing for the content of the ANT ionic stabilizer being essentially a water-soluble active organo-mineral additive containing amphoteric surfactants and microelements, %. The experimental design and the levels of the factors’ variability were specified on the basis of the test results.The principal factor exerting influence on the strength property of stabilized macadam and sand mixes is application of the ANT X3 ionic stabilizer.


2010 ◽  
Vol 139-141 ◽  
pp. 1308-1311 ◽  
Author(s):  
Jing Bing Wu ◽  
Lun Shu ◽  
He Ming Cheng

Based on the analysis and study of the composite reducer, the allocation of transmission ratio is considered to be the key to optimal design of multi-level planetary gear reducer. In view of so many discussion and study of the minimum volume as the optimization objective existed, this paper regards the maximum load capacity as the optimal goal on condition that the center distance or size is given, and then establishes the optimal mathematical model. The related constraints are given according to the theoretical knowledge and practical design experience. In this paper, an optimal function procedure that based on genetic is used to optimize the mathematical model. The satisfied result has been worked out combined with the practical example. Compared to the original program, the load capacity of 17.8% is improved. In addition, some references are provided to the optimal design of planetary gear reducer.


2021 ◽  
Vol 1042 ◽  
pp. 123-129
Author(s):  
S. Nallusamy ◽  
M. Rajaram Narayanan ◽  
K. Sujatha ◽  
R. Suganthini Rekha

The mechanical properties of epoxy granite composite are extensively influenced by the structure of porosity. The aim of this research work is to establish a mathematical model to estimate the correlation among damping and porosity. Also to estimate the correlation among flexural strength and porosity for given epoxy granite composites using experimental methods. The theoretical porosity of epoxy granite in terms of their component properties and volume fraction were determined and verified. Taguchi design of experiments was applied to plan the number of experiments to be carried out. The experimental results obtained from different test were plotted on graph over analytical results. Regression analysis was applied to establish the empirical relation between inherent properties and mechanical properties. Comparison between the analytical model and experimental results was carried out to validate the mathematical model


2020 ◽  
Vol 210 ◽  
pp. 08014
Author(s):  
Alexey Dyachenko ◽  
Tatiana Savostina

The present article is oriented on development of engineering and design parameters of a threshing separator designed as hyperboloid of revolution of one nappe for grain crop harvesting. Dependence of optimized cutting profiles on physical and mechanical properties of grain mass and parameters of a threshing separator is defined to ensure uniform supply of grain mass to threshing. The mathematical model of the profile defining process is developed to ensure uniform supply of grain mass to threshing.


Author(s):  
Olexandr Pavlenko ◽  
Serhii Dun ◽  
Maksym Skliar

In any economy there is a need for the bulky goods transportation which cannot be divided into smaller parts. Such cargoes include building structures, elements of industrial equipment, tracked or wheeled construction and agricultural machinery, heavy armored military vehicles. In any case, tractor-semitrailer should provide fast delivery of goods with minimal fuel consumption. In order to guarantee the goods delivery, tractor-semitrailers must be able to overcome the existing roads broken grade and be capable to tow a semi-trailer in off-road conditions. These properties are especially important for military equipment transportation. The important factor that determines a tractor-semitrailer mobility is its gradeability. The purpose of this work is to improve a tractor-semitrailer mobility with tractor units manufactured at PJSC “AutoKrAZ” by increasing the tractor-semitrailer gradeability. The customer requirements for a new tractor are determined by the maximizing the grade to 18°. The analysis of the characteristics of modern tractor-semitrailers for heavy haulage has shown that the highest rate of this grade is 16.7°. The factors determining the limiting gradeability value were analyzed, based on the tractor-semitrailer with a KrAZ-6510TE tractor and a semi-trailer with a full weight of 80 t. It has been developed a mathematical model to investigate the tractor and semi-trailer axles vertical reactions distribution on the tractor-semitrailer friction performances. The mathematical model has allowed to calculate the gradeability value that the tractor-semitrailer can overcome in case of wheels and road surface friction value and the tractive force magnitude from the engine. The mathematical model adequacy was confirmed by comparing the calculations results with the data of factory tests. The analysis showed that on a dry road the KrAZ-6510TE tractor with a 80 t gross weight semitrailer is capable to climb a gradient of 14,35 ° with its coupling mass full use condition. The engine's maximum torque allows the tractor-semitrailer to overcome a gradient of 10.45° It has been determined the ways to improve the design of the KrAZ-6510TE tractor to increase its gradeability. Keywords: tractor, tractor-semitrailer vehicle mobility, tractor-semitrailer vehicle gradeability.


Author(s):  
Oleksii Timkov ◽  
Dmytro Yashchenko ◽  
Volodymyr Bosenko

The article deals with the development of a physical model of a car equipped with measuring, recording and remote control equipment for experimental study of car properties. A detailed description of the design of the physical model and of the electronic modules used is given, links to application libraries and the code of the first part of the program for remote control of the model are given. Atmega microcontroller on the Arduino Uno platform was used to manage the model and register the parameters. When moving the car on the memory card saved such parameters as speed, voltage on the motor, current on the motor, the angle of the steered wheel, acceleration along three coordinate axes are recorded. Use of more powerful microcontrollers will allow to expand the list of the registered parameters of movement of the car. It is possible to measure the forces acting on the elements of the car and other parameters. In the future, it is planned to develop a mathematical model of motion of the car and check its adequacy in conducting experimental studies on maneuverability on the physical model. In addition, it is possible to conduct studies of stability and consumption of electrical energy. The physical model allows to quickly change geometric dimensions and mass parameters. In the study of highway trains, this approach will allow to investigate the various layout schemes of highway trains in the short term. It is possible to make two-axle road trains and saddle towed trains, three-way hitched trains of different layout. The results obtained will allow us to improve not only the mathematical model, but also the experimental physical model, and move on to further study the properties of hybrid road trains with an active trailer link. This approach allows to reduce material and time costs when researching the properties of cars and road trains. Keywords: car, physical model, experiment, road trains, sensor, remote control, maneuverability, stability.


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