Inertial parameter design of spatial mechanisms

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2003
Can, Fatih Cemal
In this thesis, the inertial parameters of a spatial mechanism are used in order to optimize various aspects of the dynamic behaviour of the mechanism (such as minimizing actuator torque/ force fluctuations, shaking force/moment balancing, etc.) while the effects of loads are considered as well. Here, inertial parameters refer to the mass, 6 elements of the inertia tensor and coordinates of the center of mass of the links. The concept of Force Fluctuation Number (FFN) is utilized to optimize the dynamic behaviour of the mechanism. By using the FFN concept, one obtains a number of linear equations to be satisfied by the optimal inertial parameters. In general, the number of such equations is less than the number of the inertial parameters. Therefore, some of the inertial parameters may be selected freely in order to satisfy other design constraints. Using MATHEMATICA, a program has been developed to obtain the linear equations to be satisfied by the optimal inertial parameters. The developed program includes a kinematic and force analysis module, which can be used independently for a complete kinematic and dynamic analysis of any one degree of freedom, single loop, spatial mechanism. The different closures of the mechanism may be identified by using the developed package and these analyses can be performed on any selected closure of the mechanism.

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Citation Formats
F. C. Can, “Inertial parameter design of spatial mechanisms,” M.S. - Master of Science, Middle East Technical University, 2003.