Two algorithms are presented which deal with translating an elliptic object, A, without collision amidst elliptic obstacles. These are:

(i) An exact algorithm, of complexity O(N log N), where N is the number of obstacles, yielding all directions along which the object is separable from the obstacles by a single translation.

(ii) An algorithm quadratic in N, which yields, with a degree of approximation determined by the user, a path of the object from its initial to its final position.

We consider the problem of distance estimation in the context of a mobile camera, as, for example, when the camera is attached to a robot arm. It is natural in this case to consider stereo motion, and we present here the theoretical basis for an axial stereo method based on cross-correlation using the Fast Fourier Transform, which is appropriate in the context considered here. Finally, we describe the state of implementation of the system in our laboratory.

Owing to advances in machine vision, it is now possible to study automatic gripping of moving parts. This complex task requires a precise knowledge of the displacements of objects in a camera field.

In this paper, a method to analyse the motion of parts is presented; it is based on the correlation of numerical images. The treatment of data provided by the image background makes this method quite original.

The utilization of this method, often considered as rather awkward, makes it possible, in this case, to develop a position feedback operation of the robot actuators controlled in an open loop (step by step motors).

An efficient on-line scheme for computing the inverse joint solution of robotic manipulators is combined with an improved formulation of robust, non-linear feedback control in joint space to produce a realizable Cartesian control scheme. Parametric uncertainties in the robot model are highlighted by the inclusion of compliance at each joint. Simulation results for a two link, coupled manipulator demonstrate that this Cartesian control enables the tip of the arm to track the demanded trajectory with arbitrarily small error in response to realistic actuator torques.

The paper describes a study of potential industrial applications where modular robots can be used in preference to conventional pedestal mounted robots and/or specially designed automatic machines. The study was conducted with reference to a particular family of pneumatically actuated robot modules.

The paper also describes a modular robotic system which was designed to automate assembly processes in the manufacture of a family of egg coddlers. The manipulator comprises multi-axis groups of modules which operate concurrently to perform the assembly operations. Flexibility is incorporated through the use of a hierarchical control system architecture.

One of the most important specifications associated with a robot manipulator is repeatability. Unfortunately, there are no standard procedures for determining or specifying the repeatability of a robot. This situation has resulted in a good deal of confusion when attempting to use a published repeatability specification to determine if a robot will meet the requirements of an application.

The purpose of this paper, therefore, is to propose a systematic procedure for the determination and specification of robot repeatability. To accomplish this, three aspects of repeatability analysis are examined. First, a method of collecting data to study repeatability is discussed. A data acquisition system is described as well as an associated test procedure. Next, a procedure for utilizing the acquired data to develop a repeatability specification for a robot is proposed. This procedure results in a specification of the robot's ability to orient objects as well as the classical specification for positioning repeatability. A methodical approach to determining where in the workspace the repeatability test should be made is also addressed. Finally, an approach is presented whereby the data collected during the repeatability test may be used to determine which joints contribute most to the variations in robot repeatability.

The concepts of entity-relationship diagram have been applied to picture description. Primitive picture entities, picture relationships, and picture grammars are presented with illustrative examples. A high-level description of a two-level picture generation system is proposed using either string description or ER diagram description. Illustrative examples are also given. The advantages of ER diagram description together with its comparison to string description are also presented. The results may have useful applications in robotics, artificial intelligence, expert systems, picture processing, pattern recognition, knowledge engineering and pictorial database design.

This paper presents current trends in robot programming. The open problems with current robot programming systems are outlined and indications for solutions are given. Since computer controlled robots have been introduced, the methodology of robot programming has seen a great deal of development. Two completely different approaches to robot programming have been considered in the past. On the one hand within the Artificial Intelligence community a lot of research has been done to provide robots with autonomous reasoning capabilities. On the other hand, the need to control industrial robots has pushed the development of simple but effective methods for robot programming. To put it simply, Artificial Intelligence researchers have taken a top-down approach trying to solve the difficult problem of reasoning and have assumed that all the rest was easy. Others have taken a bottom-up approach first trying to control robots and only later trying to incorporate intelligence. The complexity of industrial automation tasks requires programming systems more sophisticated that those in use today. Artificial Intelligence is the best candidate to create the next generation of robot programming systems.

In regard to work-space controller design, a derivation of the relationships between the operational approach and the decoupling method is introduced. The given generating rules, which are valid for nonredundant robots, permit the design of a Position-Speed-Acceleration controller or hybrid Force-PSA controllers.

Engineers have traditionally invested in Advanced Manufacturing Technology (AMT), such as FMS, Robots, CAD/CAM, CNC and MRP to achieve a reduction in the labour force. Similarly, government incentives for introducing AMT, have also placed an undue emphasis on the ‘need to replace labour with technology’. This policy creates severe industrial relations problems and leads to the view that technology, especially robots, ‘competes’ with human beings for employment. Research at U.M.I.S.T. has shown that AMT is much more viable when the objective of the investment is to increase a company's overall competitive ability, thereby generating increased sales which, in turn, necessitates an INCREASED labour force. The paper discusses various aspects of AMT and in each case it is shown how the acceptability of the investment is improved when the new technology is viewed ‘company-wide’. When this occurs, technology is viewed as being ‘complementary to’ and not ‘instead of’ humans.