This volume contains a series of papers originally presented at a NATO Advanced Research Workshop (ARW) entitled Kinematic and Dynamic Issues in Sensor Based Control. The workshop, one of a series concerned with topics in sensory robotics, took place at II Ciocco, Castelvecchio di Pascoli, Italy in October 1987. Attendance was by invitation only and the majority of participants are recognised leaders in their field- some from the robotics community, others with a more general control background. The main topics of interest were grouped into eight sessions represented by the eight main sections of the book: 1: Modelling Techniques: General Kinematic and Dynamic Issues 2: Sensor Signal Processing 3: Force Control 4: Further Control Topics 5: Vision Based Control 6: Further Kinematic and Dynamic Issues 7: Computational Issues 8: Learning from Sensor Input Also included are brief reports of the roundtable discussions which sought to determine important future directions of research in this area. My thanks to all those who made the workshop possible: The NATO Scientific Affairs Division and the panel on Sensory Systems for Robotic Control who provided most of the financial support; the workshop committee, Dr. B. Espiau, Dr. P. Coiffet, Dr. P.

Most industrial robots today have little or no sensory capability. Feedback is limited to information about joint positions, combined with a few interlock and timing signals. These robots can function only in an environment where the objects to be manipulated are precisely located in the proper position for the robot to grasp (i. e. , in a structured environment). For many present industrial applications, this level of performance has been adequate. With the increasing demand for high performance sensor-based robot manipulators in assembly tasks, meeting this demand and challenge can only be achieved through the consideration of: 1) efficient acquisition and processing of intemaVextemal sensory information, 2) utilization and integration of sensory information from various sensors (tactile, force, and vision) to acquire knowledge in a changing environment, 3) exploitation of inherent robotic parallel algorithms and efficient VLSI architectures for robotic computations, and finally 4) system integration into a working and functioning robotic system. This is the intent of the Workshop on Sensor-Based Robots: Algorithms and Architectures - to study the fundamental research issues and problems associated with sensor-based robot manipulators and to propose approaches and solutions from various viewpoints in improving present day robot manipula tors in the areas of sensor fusion and integration, sensory information processing, and parallel algorithms and architectures for robotic computations.

Geometry is a powerful tool to solve a great number of problems in robotics and computer vision. Impressive results have been obtained in these fields in the last decade. It is a new challenge to solve problems of the actual world which require the ability to reason about uncertainty and complex motion constraints by combining geometric, kinematic, and dynamic characteristics. A necessary step is to develop appropriate geometric reasoning techniques with reasonable computational complexity. This volume is based on a workshop held in Grenoble, France,in September 1991. It contains selected contributions on several important areas in the field of robotics and computer vision. The four chapters cover the following areas: - motion planning with kinematic and dynamic constraints, - motion planning and control in the presence of uncertainty, - geometric problems related to visual perception, -numerical problems linked to the implementation of practical algorithms for visual perception.

This book treats visual feedback control of mechanical systems, mostly robot manipulators. It not only deals with image processing techniques and robot control schemes but also covers the latest investigation of the design of the visual servo mechanism based on modern linear and nonlinear control theory, the adaptive control scheme, fuzzy logic, and neural networks. New concepts for utilizing visual sensory information for real-time manipulator control are derived and the performances are evaluated through simulations and/or experiments.The contributors to this book are robotics specialists from all over the world. The book gives a practical perspective on visual servoing to researchers, engineers, and students working in this area.

This book contains the written record of the NATO Advanced Research Workshop on Traditional and Non-Traditional Robotic Sensors held in the Hotel Villa del Mare, Maratea, Italy, August 28 - September 1, 1989. This workshop was organized under the auspicies of the NATO Special Program on Sensory Systems for Robotic Control. Professor Frans Groen from the University of Amsterdam and Dr. Gert Hirzinger from the German Aerospace Research Establishment (DLR) served as members of the organizing committee for this workshop. Research in the area of robotic sensors is necessary in order to support a wide range of applications, including: industrial automation, space robotics, image analysis, microelectronics, and intelligent sensors. This workshop focused on the role of traditional and non-traditional sensors in robotics. In particular, the following three topics were explored: - Sensor development and technology, - Multisensor integration techniques, - Application area requirements which motivate sensor development directions. This workshop'brought together experts from NATO countries to discuss recent developments in these three areas. Many new directions (or new directions on old problems) were proposed. Existing sensors should be pushed into new application domains such as medical robotics and space robotics.

Design of intelligent robots is one of the most important endeavors in robotics research today. The key to intelligent robot design lies in sensory systems for robotic control and manipulation. In an unstructural environment, robotic sensing translates measurements and characteristics of the environment and working objects into useful information. A robotic system is usually equipped with a variety of sensors to perform redundant sensing and achieve data fusion. This book contains revised versions of papers presented at a NATO Advanced Research Workshop held in Florida in September 1989 within the activities of the NATO Special Programme on Sensory Systems for Robotic Control. The fundamental issues addressed in this volume were: - Theory and techniques, including knowledge-based systems, geometrical fusion, Boolean fusion, probabilistic fusion, feature-based fusion, error-estimation approach, and Markov process modeling. - General concepts, including microscopic redundancy at the sensory element level, macroscopic redundancy at the sensory system level, parallel redundancy, and standby redundancy. - Implementation and application, including robotic control, sensory technology, robotic assembly, robot fingers, sensory signal processing, sensory system integration, and PAPIA architecture. - Biological analogies, including neural nets, pattern recognition, low-level fusion, and motor learning.

T. Viéville: A Few Steps Towards 3D Active Vision appears as Vol. 33 in the Springer Series in Information Sciences. A specific problem in the field of active vision is analyzed, namely how suitable is it to explicitly use 3D visual cues in a reactive visual task? The author has collected a set of studies on this subject and has used these experimental and theoretical developments to propose a synthetic view on the problem, completed by some specific experiments. With this book scientists and graduate students will have a complete set of methods, algorithms, and experiments to introduce 3D visual cues in active visual perception mechanisms, e.g. autocalibration of visual sensors on robotic heads and mobile robots. Analogies with biological visual systems provide an easy introduction to this subject.

This volume contains revised papers based on contributions to the NATO Advanced Research Workshop on Multisensor Fusion for Computer Vision, held in Grenoble, France, in June 1989. The 24 papers presented here cover a broad range of topics, including the principles and issues in multisensor fusion, information fusion for navigation, multisensor fusion for object recognition, network approaches to multisensor fusion, computer architectures for multi sensor fusion, and applications of multisensor fusion. The participants met in the beautiful surroundings of Mont Belledonne in Grenoble to discuss their current work in a setting conducive to interaction and the exchange of ideas. Each participant is a recognized leader in his or her area in the academic, governmental, or industrial research community. The workshop focused on techniques for the fusion or integration of sensor information to achieve the optimum interpretation of a scene. Several participants presented novel points of view on the integration of information. The 24 papers presented in this volume are based on those collected by the editor after the workshop, and reflect various aspects of our discussions. The papers are organized into five parts, as follows.

Limp materials are used in many economically impo~tant industries such as garment manufacture, shoe manufacture, aerospace (composites) and automobiles (seats and trim). The use of sensors is essential for reliable robotic handling of these materials, which are often based on naturally occurring substances such as cotton and leather. The materials are limp and have non-homogeneous mechanical properties which are often impossible to predict accurately. The applications are very demanding for vision and tactile sensing and signal processing, adaptive control systems, planning and systems integration. This book comprises the collection of papers presented at the NATO Advanced Research Workshop on 'Sensory Robotics for the Handling of Limp Materials', held in October 1988 at II Ciocco, Tuscany, Italy. The aim of the workshop was to examine the state of the art and determine what research is needed to provide the theoretical and technological tools for the successful application of sensory robotics to the handling of limp materials. The meeting also acted as the first-ever forum for the interchange of knowledge between applications-driven researchers and those researching into the provision of fundamental tools. The participants were drawn from academia (20), industry (5), and other non-university research organisations (5).

The successful implementation of applications in spatial reasoning requires paying attention to the representation of spatial data. In particular, an integrated and uniform treatment of different spatial features is necessary in order to enable the reasoning to proceed quickly. Currently, the most prevalent features are points, rectangles, lines, regions, surfaces, and volumes. As an example of a reasoning task consider a query of the form "find all cities with population in excess of 5,000 in wheat growing regions within 10 miles of the Mississippi River. " Note that this query is quite complex. It requires- processing a line map (for the river), creating a corridor or buffer (to find the area within 10 miles of the river), a region map (for the wheat), and a point map (for the cities). Spatial reasoning is eased by spatially sorting the data (i. e. , a spatial index). In this paper we show how hierarchical data structures can be used to facilitate this process. They are based on the principle of recursive decomposition (similar to divide and conquer methods). In essence, they are used primarily as devices to sort data of more than one dimension and different spatial types. The term quadtree is often used to describe this class of data structures. In this paper, we focus on recent developments in the use of quadtree methods. We concentrate primarily on region data. For a more extensive treatment of this subject, see [SameS4a, SameSSa, SameSSb, SameSSc, SameSga, SameSgbj.