Methodology for Calculating the Resolution of a Planar Parallel Mechanism

摘要

There exists factors that will affect the workings of a machine or mechanism. This paper proposes a methodology to analyze the variations in the positions of the 3RRR Planar Parallel Mechanism. This methodology is called point-point and it consists in plotting a straight line inside the workspace as ideal trajectory lines of reference, horizontal as well as vertically, this shifts the mobile platform following the tangents while plotting the points that it obtains. From these points and the reference line the resolution is calculated, and the accuracy and the approximation error to the straight line. It can be concluded that in the 3RRR PPM, the exactitude is different in its horizontal movements then in its vertical movements; and that the resolution does not improve even when the steps (microsteps) are decreased, and the error of approximation increases as it advances in the direction of the tangent no matter if it's a normal step or a microstep.