Simulation of Output Angle Error of Spatial 7R 7-Link Mechanisms with Intersecting Axes

Abstract

The direction of driven link of the spatial 7R 7-link mechanism is expressed by two angles in the case where three adjacent axes and two adjacent axes intersect a point respectively. Namely, the driven link can be connected by universal joints at both ends, so this type of mechanism has two output angles. It is difficult to simulate the output angle error using the method of sensitivity analysis, because it is needed that the simulation using the same value of deviation of the kinematic constants agrees with two output angle error, simultaneously. In this paper, we show that the simulation can be done appropriately assuming the functional relationship between the input angle and the deviation of kinematic constants, and that functional relationship concerns with the input moment and the motion transmissibility.