Optimization of vibrator motion with air flow excitation

In the daily life and techniques people constantly interact with continuous media such like air or water. In this paper motion of a vibrator with constant air or water flow excitation is considered. Firstly, motion of the vibrator with constant air or water flow velocity excitation is investigated. The main idea is to determine optimal control law for variation of additional area of vibrating object within limits. The criterion of optimization is time required to move object from initial position to the final one. The maximum principle is used for solution of the high-speed problem. It is demonstrated that optimal control action is on bounds of area limits. Examples of synthesis of real mechatronic systems are give

Fiber orientation in viscous fluid flow with and without vibration

This early-stage investigation is related to determination of flow speed gradients of fresh steel fiber-reinforced concrete (SFRC). They are assumed to be the key parameters for computer modeling of orientation of steel fibers in form casting process. The aim of the research is to elaborate a computer model for evaluation of steel fiber orientation in casting process, which would provide an attractive possibility to predict concrete mechanical properties, optimization of casting process and costs due to proper use of ingredients. Fiber orientation in FRC is important for ensuring the best mechanical properties in the places where it is necessary. Task can be solved as: to obtain optimal fiber concentration and orientation or to use appropriate casting approach of concrete with the goal to obtain required mechanical properties in appropriate locations of the composite element. As an example the paper considers the case of trench filling by fiber concrete. Simulations provided distributions of vertical and horizontal velocities in real-time scale. Behavior of a single fiber in an inclined container with a viscous transparent liquid (potato-starch solution) was analyzed in order to confirm the possibility to obtain orientation of fibers on the basis of velocity gradients in viscous fluid. For precise modeling of potato-starch liquid, coefficient of dynamic viscosity was determined. The experiments performed on fibers in an inclined container demonstrated satisfactory agreement with the simulation results. Performed analysis indicates that velocity gradients can be applied for determination of position and orientation of fibers in fabrication of fiber-reinforced concrete product

Fin type propulsive devices with varying working area of vibrating tail

The object of the study is a fin type propulsive device of robotic fish moving inside water. The aim of the study is to establish optimal control law for variation of additional area of vibrating tail, which ensures maximal positive impulse of motive forces acting on tail. The problem has been solved using the maximum principle of Pontryagin. It is demonstrated that optimal control action corresponds to the case of bound values of area limits. The proposed method makes it possible to increase effective surface area of the fin within motion cycles, when useful tractive force is formed. But within cycles, when fin motion is hindered by water resistance forces, effective surface area is decreased. Thanks to this energy losses are minimized, and operation of fin propulsive device becomes more effective. Examples on synthesis of real mechatronic systems are provided as wel

Fiber orientation in viscous fluid flow with and without vibration

This early-stage investigation is related to determination of flow speed gradients of fresh steel fiber-reinforced concrete (SFRC). They are assumed to be the key parameters for computer modeling of orientation of steel fibers in form casting process. The aim of the research is to elaborate a computer model for evaluation of steel fiber orientation in casting process, which would provide an attractive possibility to predict concrete mechanical properties, optimization of casting process and costs due to proper use of ingredients. Fiber orientation in FRC is important for ensuring the best mechanical properties in the places where it is necessary. Task can be solved as: to obtain optimal fiber concentration and orientation or to use appropriate casting approach of concrete with the goal to obtain required mechanical properties in appropriate locations of the composite element. As an example the paper considers the case of trench filling by fiber concrete. Simulations provided distributions of vertical and horizontal velocities in real-time scale. Behavior of a single fiber in an inclined container with a viscous transparent liquid (potato-starch solution) was analyzed in order to confirm the possibility to obtain orientation of fibers on the basis of velocity gradients in viscous fluid. For precise modeling of potato-starch liquid, coefficient of dynamic viscosity was determined. The experiments performed on fibers in an inclined container demonstrated satisfactory agreement with the simulation results. Performed analysis indicates that velocity gradients can be applied for determination of position and orientation of fibers in fabrication of fiber-reinforced concrete product

Modernization of railway light led driver

The proof of the positive and negative aspects of various types of optical systems that have been introduced by the railway network. Special attention is paid to special LED lamps and their power driver modernization. Modelling of the power driver circuit in the SIMULINK environment has been finished

Modernization of railway light led driver

The proof of the positive and negative aspects of various types of optical systems that have been introduced by the railway network. Special attention is paid to special LED lamps and their power driver modernization. Modelling of the power driver circuit in the SIMULINK environment has been finished