Measurement Indices of Positional Uncertainty for Plane Line Segments Based on the εσ Model

摘要

Firstly,eight cases of the random line segments are discussed. Secondly,to the eight existing cases of line segment,the analytic expressions of the error band for the εσ uncertainty model of line segment are deduced,the parameter equations of the error band boundary are gotten,and it is proved that the boundary of the error band is continuous. Thirdly,the average error band width and the algebraic expressions of the uncertainty region area bounded by error band are calculated. Finally,the visual graphics of the error band are drawn with analytic expression of the error band by examples. Thus,three indexes are given to measure the precision of the line uncertainty: the average error band width,the uncertainty region area and the visual graphics.