9 research outputs found
The impact of the kinematic parameters of bounce and pitch motions of sprung mass on wheeled vehicles handling
The impact of the kinematic parameters of bounce and pitch motions of wheeled vehicles’ (WVs’) sprung mass (SM) with non-linear power characteristics of the cushion system on vehicles handling is studied. The dependence of the critical value of the dynamic steering angle of directive wheels on the amplitude of bounce and pitch motions and the kinematic parameters of motion is developed. It is proven that the limit value of the dynamic steering angle of directive wheels is reduced during acceleration, and vice versa (it increases during braking, while the bounce and pitch motions are significantly reduced)
Methodology of Force Parameters Justification of the Controlled Steering Wheel Suspension
The methodology for selecting the main force parameters of nonlinear nonconservative suspension for the main performance characteristics of wheeled vehicles has been developed based on the longitudinal-angular oscillations. The following has been established: a) change limits of static deformation of the elastic suspension system and its other parameters at which the basic operational characteristics for various ranges of amplitude change are satisfied; b) the amplitude of the initial perturbation of oscillations
depending on the shape of the inequality and its entry speed; c) the influence of the main characteristics of damping devices on the amplitude frequency characteristics. The results of this work can be a basis for the choice of such parameters of the considered controlled suspension, which ensure the stability of the vehicle along the curved sections of the road, its controllability, etc
Rozwój Open Access na Ukrainie na przykładzie elektronicznego repozytorium Uniwersytetu Narodowego „Politechnika Lwowska”
[Developing Open Access in Ukraine – an example of electronic repository of the Lviv Polytechnic National University] Rapid development of information technology has a deep impact on the nature of worldwide scientific communication. In accordance with the mission of disseminating knowledge, well-known academic institutions not only gather information about academic achievements of their employees, but also build repositories that expose digital content to its members and to the broader research community. The paper presents the development of electronic archives in academies of Ukraine over the past 5 years. Content and size of the archives is characterized. The authors describe the creation process and operating principles of scientific electronic repository „Electronic Scientific Archive of the Lviv Polytechnic National University” (http://ena.lp.edu.ua). Conditions that are necessary for effective development of university repositories, document sources, provision and promotion of the idea of open access are considered. The authors analyze growth of the electronic repository of Lviv Polytechnic National University in the first year of operation and provide usage statistics by different categories of users, including Polish scientists. For statistical data analysis DSpace and Google Analytics tools were used. Major sources of electronic documents in the electronic repository of Lviv Polytechnic National University are defined. The authors conclude that effective cooperation between librarians and researchers is crucial factor in the successful development of an institutional repository
Interpreting the Main Power Characteristics Choice of the Wheel Vehicles Guided Cushioning System
The method of investigation of the non-linear vibrations of the wheel vehicles with the guided cushioning system has been developed. It is based on the idea of the perturbation methods combined with the theory of special periodic Atebfunctions. All these made possible to obtain analytical relations, which describe the characteristic features of the cushioning area vibrations. These relations can be the basis for creation of the software product of the guided cushioning system with the purpose to minimize the dynamic loadings on the transported people and cargo and to increase the stability characteristics of the vehicle movement along the curvilinear areas of the bump road
Study on Nonlinear Model of Dynamics of a System ‘Extruder Elastic Auger Working Body’
The model of dynamics of a system ‘extruder elastic auger working body’ is developed. The design of an extruder elastic screw working body is worked out. The article provides the proposition of calculation technique for determining of the theoretical dependences that would analyse the laws of amplitude changing and oscillation phase of a system ‘elastic auger working body’ in the non-resonant case. It also provides analytical dependences determining the characteristic features of different geometrical parameters of an extruder working body
THE IMPACT OF THE KINEMATIC PARAMETERS OF BOUNCE AND PITCH MOTIONS OF SPRUNG MASS ON WHEELED VEHICLES HANDLING
The impact of the kinematic parameters of bounce and pitch motions of wheeled vehicles’ (WVs’) sprung mass (SM) with non-linear power characteristics of the cushion system on vehicles handling is studied. The dependence of the critical value of the dynamic steering angle of directive wheels on the amplitude of bounce and pitch motions and the kinematic parameters of motion is developed. It is proven that the limit value of the dynamic steering angle of directive wheels is reduced during acceleration, and vice versa (it increases during braking, while the bounce and pitch motions are significantly
reduced)
Моделювання динаміки вібраційного сепаратора барабанного типу з концентричним розміщенням сит
In order to provide for a more efficient process of separation, we propose a new type of separator, in particular separator of the drum-vibratory type. It has a number of advantages over other separators:1) characterized by simplicity of design and maintenance;2) low sensitivity to the properties of the separated mixture;3) a variety of oscillation modes;4) possibility to automate the process of separation.In order to design a separator, theoretical study was conducted into its dynamics for the purpose of examining the impact of its structural and kinematic indicators on the intensity of separation process of bulk mixtures. This problem was solved by constructing a nonlinear mathematical model that describes dynamics of the separator. The model is built based on a number of mathematical methods and laws, in particular the asymptotic methods of nonlinear mechanics. It is a system of non-linear analytic expressions, which in character format includes kinematic and geometric parameters of separator. Based on the model and our studies, we selected parameters for a vibratory separator of the drum type, which will provide the most effective separation of mixtures according to the selected criteria.The developed mathematical model is uniform and parameterized. It allows speeding up the process to design a separator. It can be also used for designing and selecting the operation modes of separators of different types with a vibration drive, as well as for other vibratory processing machines.Разработана новая конструкция вибрационного сепаратора барабанного типа с концентрическим размещением сит и построена математическая модель описания его динамики, которая является нелинейной, унифицированной и параметрической. С ее помощью определено влияние основных конструкционных параметров сепаратора и кинематических показателей его привода на характеристики его движения и интенсивность процесса сепарации. Экспериментальные исследования подтвердили достоверность полученной моделиРозроблено нову конструкцію вібраційного сепаратора барабанного типу з концентричним розміщенням сит та побудовано математичну модель опису його динаміки, яка є нелінійною, уніфікованою та параметричною. За допомогою неї визначено вплив основних конструктивних параметрів сепаратора і кінематичних показників його приводу на характеристики його руху та інтенсивність процесу сепарації. Експериментальні дослідження підтвердили достовірність отриманої модел
Поздовжньо-кутові коливання колісних транспортних засобів із нелінійною силовою характеристикою системи підресорювання
Отримано у параметризованій формі аналітичні залежності, які описують визначальні параметри поздовжньо-кутових коливань підресореної частини колісних транспортних засобів. Показано, що для колісних транспортних засобів спеціального призначення, за базу яких вибрано шасі серійних автомобілів, більшою мірою ергономічним умовам задовольняє система підвіски з прогресивним законом зміни пружних амортизаторів.An in parameterized form of analytical dependences that describe the parameters defining a longitudinally - angular oscillation of the sprung wheeled vehicles. It is shown that for wheeled vehicles for special purposes for which the base is selected chassis production car, more ergonomically satisfying the conditions of suspension system with progressive law change resilient shock absorbers