Problems with standard Boolean maps produced through subjective interpretation of a phenomenon (i.e., forest or soils maps) are discussed and two alternatives based on spatial certainty are presented and discussed. One requires multiple interpretations of the phenomenon in order to construct a library of spatial uncertainties; such an Uncertainty Library can be used subsequently to estimate err...

We describe techniques for performing mobile robot localization using occupancy grids that allow subpixel localization and uncertainty estimation in the pixelized pose space. The techniques are based on a localization method where matching is performed between the visible landmarks at the current robot position and a previously generated map of the environment. A likelihood function over the sp...

This paper proposes a method to autonomously select stable visual landmarks from observed features by stereo vision and a given 2D obstacle map. The robot selects as stable landmarks vertical line segments which are distinct and on a vertical plane, because they are expected to be observed reliably from various viewpoints. Due to the vision and motion error of the robot, the observed feature po...

We present an incremental map building approach that is applied by a group of cooperating heterogeneous robots. Robots cooperate by sharing information in order to build their own maps. Environment information comes into the mapping process from two different sources: aerial images from a helicopter and sonar readings from several ground robots. Ground robots use the resulting map to plan paths...

This paper proposes a method to autonomously select stable visual landmarks from observed features by stereo vision and a given 2D obstacle map. The robot selects as stable landmarks vertical line segments which are distinct and on a vertical plane, because they are expected to be observed reliably from various viewpoints. Due to the vision and motion error of the robot, the observed feature po...

Risk maps are spatial models of environmental hazards such as predation on livestock. We tested the long-term validity of a published risk map built from locations where Wisconsin wolves attacked livestock from 1999-2006. Using data collected after model construction, we verified the predictive accuracy of the risk map exceeded 91% for the period 2007-2011. Predictive power lasting 5 years or m...

This paper proposes a method to extract on-line stable visual landmarks from sensory data obtained by stereo vision so as to adapt to changes of environment. Given a two-dimensional obstacle map, the robot Ž rst extracts vertical line segments which are distinct and inside planar surfaces not near boundary edges as they are expected to be observed reliably from various viewpoints. However, the ...

The Bayesian approach allows one to combine measurement data with prior knowledge about models of reality to draw inferences about the validity of those models. The posterior probability quantifies the degree of certainty one has about those models. We propose a method to explore the reliability, or uncertainty, of specific features of a Bayesian solution. If one draws an analogy between the ne...

In this paper we present an approach for multi-robot cooperative exploration based on the potential field generated by several basic behaviours. When an unknown environment is explored the uncertainty in the localization normally grows, this fact may cause the failure of the Simultaneous Localization and Mapping (SLAM) algorithm, and thus constructing an useless and inaccurate map. The explorat...

While the process of modeling and mapping a 100-year floodplain is inherently full of uncertainty, engineers are still required to determine a single line boundary for flood insurance rate and other floodplain studies. This is despite the fact that a good engineer knows that, within reasonable limits, different modeling parameters can be chosen that result in shifting the floodplain boundary ei...