ABSTRACT
The present paper proposes a method for evaluating the change in the kinematic free response for a torque pulse input in mechanisms and mechanical systems. Therefore, two generic four-bar mechanisms were analysed, doing the initial flywheel sizing based on the energy variations in one revolution of the system by a developed method of integration and stipulating a coefficient of fluctuation in the recommended intervals. The changes in the angular velocities were obtained by the power spectral density (PSD) with Welch’s method, varying the number of points of the fast Fourier transform (NFFT), evaluating the magnitude (PSD) and frequency changes by a created C-coefficient, considering both. For coefficients close to the natural, no relevant frequency change was observed, compared with the magnitude changes, also noting that the C-coefficient changes exponentially when it is distant from the natural value, without flywheel. Significant changes were computed showing the sensitivity of the method, stabilising with the increase of the NFFT. For the integration method for flywheel sizing, a good result was obtained with small angle steps and small torque curves, obtaining an error of 0.00001 in the case of study.
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Yago Pablo Rodrigues Bueno
Yago P. R. Bueno is an Undergraduate Student of Mechanical Engineering at Federal Institute of Education, Science and Technology of Piauí, Brazil. He develops research in the areas of Mechanical Design, Solid Mechanics, Numerical Methods, Dynamics and Vibration of Mechanical Systems. He has also developed research in the areas of Vehicle Dynamics, Analysis of Composite Materials and Experimental Stress Analysis applied to high performance bicycles while Intern in an industry of the branch.
Ricardo Cardoso Soares
Msc. Ricardo C. Soares is M.Tech, effective professor of Mechanical Engineering at Federal Institute of Piauí, Brazil. He received his B.Tech in Mechanical Engineering from Federal Institute of Piauí, Brazil in 2012, M. Tech in Mechanical Engineering from Federal University of Santa Catarina, Brazil in 2018. His researchs are based in Mechanical Mechanisms, Vehicle Dynamics, Fatigue Methods and Stress Analysis. He is currently working in Numerical Analysis of Dynamics Vehicle.