An investigation of the effects of various error components in a mobile robot system, which uses a navigation line, was previously reported by the author in 1985. An analysis of the effects of these error components on the navigation line-width determination and obstacle-range determination is presented that provided equations that are used to predict the error resulting from changes in various system parameters. In particular, the change in the rotation angle of the robot sensor about its optical axis, called the roll angle, is examined. Numerical examples showing the characteristics of the derived error equations are also given.>

Experimental results are presented that support theory published in the literature concerning the use of a navigation line for the guidance of mobile robots. A method for the determination of a robot's position is developed. A specialized edge operator, which aids in the segmentation of a navigation line from an image of a robot's environment, is given. Use of this specialized edge operator in conjunction with the Hough transform is also presented. These methods are used to verify the analytical results given previously. Comparisons are made between experimental data and expected results as a function of various system parameters. Real-time implementation of these methods is considered.

A continuous, straight-edged line is used for the visual navigation of an autonomous mobile robot in a factor environment. This line, which resides on the floor and contrasts with background, may also be used to determine range information. Two methods are developed for determining the range of an object in the sensor's field of view. The effects of various error conditions in the system geometry on each ranging method are determined. Equations are derived which yield the percent error in calculating ranges given estimates of these error conditions. Numerical examples using typical sensor parameters are given.

The use of a contrasting line for the visual navigation of autonomous mobile robots in a factory environment is developed. Minimum and maximum linewidths are determined analytically by considering sensor geometry, field of view, and error conditions present in the system. The effects of these error conditions on the width of the line, as seen in the image plane, determines the optimal linewidth. Numerical examples using typical sensor parameters are given.