Drive Selection of Multidirectional Mechanism with Excess Inputs

Mechanisms with excess inputs are mechanisms in which the number of engines is higher than the number of degrees of freedom. While the mechanism is in operation, some engines are disengaging, while other engines are switching on, whereas the number of active engines at each given moment equals the number of degrees of freedom. These mechanisms create better conditions for power transmission than mechanisms without excess inputs. However to realize full potential of these mechanisms it is necessary to solve the problem of operational drive selection. This article describes a mechanism of a spatial platform with excess inputs. For the purpose of this article, the following criteria were used to carry out a quality assessment of the configuration presented below: Jacobian determinant of equations in sequence for geometric analysis of the mechanism, sum of squares of the balancing forces and minimal natural frequency of the mechanism with fixed engines and flexible transmission device. This article also considers variations of motion of the movable operating element at pre-set conditions with an alternative engines activation under all three mentioned criteria, as well as variations for simultaneous operation of all engines.