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I n t h e p r e s e n t work, t h e s t a t i c balancing of the forearm of a robot i s analyzed; the advantages and disadvantages of using a mass o r a s p r i n g f o r t h e balancing are discussed and t h e i r e f f e c t s on t h e s y s t e m n a t u r a l f r e q u e n c i e s a r e i l l u s r a t e d u s i n g numerical examples.The three-dimensional finite element analysis has been used as a mathematical t o o l f o r f i n d i n g t h e n a t u r a l f r e q u e n c i e s .

The prediction of boiling burnout in the jet-disk configuration by Lienhard and Eichhorn (based on the mechanical energy stability criterion) is used to recorrelate the data of Katto, Monde, and others. This new correlation includes the identification of the ranges of influence of viscosity (of a Reynolds number) and of gravity (of a Froude number.) The correlation brings the data together within a standard deviation of ±8.66 percent in the range in which viscosity and gravity exert no influence.

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The dynamic analysis of an elastically supported lathe spindle-workpiece system subjected to random cutting forces is presented. The stochastic partial differential equation characterizing the behavior of the system was formulated from the Euler-Bernouli equation. Based on free vibration analysis and experimental verification of the natural frequencies, the hinged boundary condition was considered for the running center. A finite element technique in conjunction with the modal analysis method were used to calculate the mean square displacement of the workpiece. The experimentally calculated power spectral density of the cutting forces was used as the input excitation to the mathematical model. The effect of bearing stiffness and damping, and bearing spacing on the mean square displacement were studied. A direct search optimization technique was carried out to select optimal bearing stiffness and the bearing spacing. Results are presented in the form of plots and tables.