Effect of the Magnetic Force on Ferrite Pendulum Oscillation Parameters: Parametric Analysis on Ferrite Pendulum

The magnitude of the damping force of the mathematical pendulum swinging on a medium is usually proportional to the speed of the pendulum. In this research, the pendulum oscillation parameters oscillating on an air medium under the influence of a magnetic field of 1.8 G will be investigated. In the initial stage, the effect of the magnetic force on the damping coefficient of ferrite pendulum oscillations with an initial deviation of 15 degrees observed. Furthermore, the study continued with varying the angle of deviation from 5 degrees to 25 degrees. The results of the data fitting amplitude (xi) at various swing times (ti) are using to analyze the effect of the angle of deviation on the maximum amplitude. The results showed that for the deviation angle of 15o the coefficient of damping of the medium affected by the magnetic force was 0,0022 greater than the coefficient of air damping 0,00006. It affects the amplitude, which decreases faster than the pendulum amplitude without the influence of magnetic force. Variation in the angle of deviation also affects the amplitude of the pendulum. In the deviation angle below 10, the pendulum motion is more influenced by the magnetic force, whereas in the deviation above 10, the pendulum motion is more dominated by gravity.

Laterale Pendelschwingungen beim Reiben*/Lateral pendulum oscillation in reaming

Geriebene Präzisionsbohrungen finden in vielen Branchen Anwendung, besonders die Automobilindustrie und Hydraulik-/Pneumatikbranche sind hier von großer Bedeutung. Bei der Serienfertigung von Komponenten des Antriebsstrangs, speziell des Motorblocks, ist das Einbringen von Präzisionsbohrungen unerlässlich für die Funktionserfüllung. Dieser Fachaufsatz befasst sich mit der Simulation des Reibprozesses und der experimentellen Verifizierung. Besondere Aufmerksamkeit gilt hierbei dem Effekt der lateralen Pendelschwingung.   Reamed precision drillings are used in many industries, especially the automotive industry and hydraulics / pneumatic industry are of great importance here. In the production of components of the powertrain, especially the engine block, the introduction of precision drillings is essential for the functionality of the workpiece. This technical paper describes the simulation of the reaming-process and its experimental verification. Particular attention is given to the effect of the lateral pendulum.

Analysis Characteristics Of Pendulum Oscillation In PLTGL-SB

Energy is an everlasting demand which sustains humanity and its activity throughout the world. The main problem energy for all country is still using fossil energy. Using fossil energy caused pollution and contaminate environment. Adopting Ocean wave energy we can convert the wave into eco-green energy. Wave energy in Indonesia very abundant, it’s coastal line is 95,181 km number 2 in the world after Canada. The device that used to convert ocean wave energy into electrical energy is called WECs (Wave Energy Converters). Latterly, there are many kinds of WECs that already developed by an engineer. Pendulum system is one sample of WECs, its has uncomplicated working principle. Zamrisyaf is The man who first invented the device in 2010. Recently, the researcher still haven’t found the parameter of pontoon geometry that can afford a good sea keeping for this WECs. In this research, the authors has been performed using experimental approach to test the pendulum system. The purpose of this study is to analyze the novel geometry of pontoon that identical to trimaran that can produce a large amplitude of pendulum oscillation through an experimental approach. The analyzed aspect is the combination of outrigger length, outrigger height, pendulum rod length, pendulum mass, and wave periods which have a maximum amplitude of pendulum oscillation. The analysis results show that the better solution is pontoon thus has outrigger height of 40 mm, pendulum rod length of 106.7 mm, outrigger length of 413 mm, pendulum mass of 20, and wave periods of 0.8 s have a maximum amplitude of pendulum oscillation as big as 60 degrees.

Holonomicity analysis of electromechanical systems

Electromechanical systems are described using state variables that contain electrical and mechanical components. The equations of motion, both electrical and mechanical, describe the relationships between these components. These equations are obtained using Lagrange functions. On the basis of the function and Lagrange - d’Alembert equation the methodology of obtaining equations for electromechanical systems was presented, together with a discussion of the nonholonomicity of these systems. The electromechanical system in the form of a single-phase reluctance motor was used to verify the presented method. Mechanical system was built as a system, which can oscillate as the element of physical pendulum. On the base of the pendulum oscillation, parameters of the electromechanical system were defined. The identification of the motor electric parameters as a function of the rotation angle was carried out. In this paper the characteristics and motion equations parameters of the motor are presented. The parameters of the motion equations obtained from the experiment and from the second order Lagrange equations are compared.

On nonlinear dynamics of a parametrically excited pendulum using both active control and passive rotational (MR) damper

This paper presents two control strategies for a parametrically excited pendulum with chaotic behavior. One of them considers active control obtained by nonlinear saturation control (NSC) and the other a passive rotational magnetorheological (MR) damper. Firstly, the active control problem was formulated in order to design the external torque for the pendulum, considering the NSC. Numerical simulations were carried out in order to show the effectiveness of this method for the active control of the pendulum oscillation. The ability of the control of the proposed NSC in suppression of the chaotic behavior, considering the proposed parameters, was tested by a sensitivity analysis to parametric uncertainties. In the case of the passive rotational MR damper, firstly the influence of the introduction of the MR in a pendulum was performed considering the 0-1 test. Different electric currents are applied to suppress the chaotic behavior of the system. The numerical results showed that the simple introduction of a passive rotational MR damper without electric current did not change the chaotic behavior of the system. However, it is possible to keep the pendulum oscillating with periodic behavior using the rotational MR damper with energizing discontinuity.

Vibration Analysis of the Free-Falling Microstructure Profiler

Free-falling microstructure profiler (FFMP) is the most effective platform for measuring ocean microstructure turbulence. Vibration is the key factor of influencing the accuracy of the measurement of the shear sensor mounted on the leading end of the FFMP. In the present work, vibration behavior of an FFMP called FFMP1000 was studied through fluid–structure interaction (FSI) simulations and field trials. Vibration characteristics and mechanism of the FFMP1000 were also discussed. Results showed that motion of the FFMP was like a compound pendulum oscillation, and was caused by vortex shedding at the trailing end of the FFMP. Empirical formulas used to predict the oscillation of the FFMP were deduced based on the characteristics of motion behavior and confirmed through sea trials. The present achievement provides scientific guidance for designing optimal hydrodynamic hull shape of the FFMP. It is also useful to estimate the low end detection limit of the FFMP and to modify the turbulence kinetic energy dissipation rate during ocean observations.

A Simple Method for Solving Dynamic Problems of Robotics

In this paper we find a general solution for the action function in the case of a heavy point moving on a sphere using the method of separation of the Hamilton-Jacobi equation variables. The solution contains two constants: the energy of a material point and the momentum projection onto a horizontal direction. We analyze the modes of a spherical pendulum oscillation. It is shown that the solution does not contain any errors of accumulation which are characteristic for evolution problems with long prediction periods.