This paper addresses the coupled tasks of constructing a spatial representation of the environment with a mobile robot using noisy sensors (sonar) and using such a map to determine the robot's position. The map is not meant to represent the actual spatial structure of the environment so much as it is meant to represent the major structural components of what the robot \sees". This can, in turn,...

Self-supervised learning (SSL) is a reliable learning mechanism in which a robot enhances its perceptual capabilities. Typically, in SSL a trusted, primary sensor cue provides supervised training data to a secondary sensor cue. In this article, a theoretical analysis is performed on the fusion of the primary and secondary cue in a minimal model of SSL. A proof is provided that determines the sp...

In this paper, we show how linguistic expressions can be generated to describe the spatial relations between a mobile robot and its environment, using readings from a ring of sonar sensors. Our work is motivated by the study of human-robot communication for novice robot users. The ultimate goal is to exploit these linguistic expressions for navigation of the mobile robot in an unknown environme...

Mobile robots need to navigate in their environment in order to perform useful tasks. Doors appear in almost every office-like indoor environment and they have to be crossed often during the navigation process. We present in this paper a new approach that uses visual information to anticipate that a door has to be crossed. Combining then visual information with ultrasonic sensors, the robot app...

Robotics research is heavily dependent on fast, accurate, reliable and cheap sensors. Sonar sensing can fulfil these requirements in air and underwater environments. Moreover sonar physics provides robotics researchers with a natural selection capability for landmark detection in navigation problems. This paper presents new sonar results that allow high-speed accurate measurement and classifica...

Our goal is to manipulate and guide an object across an unknown environment toward a goal in a known location in space. Our tools include a system of manipulation robots, which are “blind” and one mobile scout robot who relies on a series of sonar sensors for information about the environment. Previous solutions to this problem have taken a simultaneous guiding and manipulating approach, moving...

This paper proposes an exploration method for robots equipped with a set of sonar sensors that does not allow for complete coverage of the robot’s close surroundings. In such cases, there is a high risk of collision with possible undetected obstacles. The proposed method, adapted for use in urban outdoors environments, minimizes such risks while guiding the robot towards a predefined target loc...

In this paper we describe our effort to automate ship hull inspection for security applications. Our main contribution is a system that is capable of drift-free self-localization on a ship hull for extended periods of time. Maintaining accurate localization for the duration of a mission is important for navigation and for ensuring full coverage of the area to be inspected. We exclusively use on...

Noise fields in most sonar models are characterized nonparametrically wherein a noise coherence matrix for the array of sensors is estimated across frequency. Arrays are now becoming so large that is difficult to estimate this matrix reliably because of the nonstationarity. In many environments shipping is a dominant part of the noise field and it does not take much source receiver motion to le...

We present an approach for indoor mapping and localisation using sparse range data, acquired by a mobile robot equipped with sonar sensors. The paper consists of two main parts. First, a split and merge based method for dividing a given metric map into distinct regions is presented, thus creating a topological map in a metric framework. Spatial information extracted from this map is then used f...