The complex model presented in this paper consists of three main parts: (a) a model of the robot; (b) tools for building and displaying models of workpieces to be painted; (c) a model of the spatial distribution of the paint particles. The simulation process is preceded by the creation of the surface to be coated. A colour graphic display is used for this purpose. The surface appears on the screen together with the robot (hidden line elimination is included). The “spray gun” is installed at the robot's tip and its orientation, performance and other characteristics are to be set. The paint particles sprayed are supposed to form a cone, and by considering its intersection with the surface, the amount of paint delivered to any point can be evaluated and visualized in different colours. The operator simulates the process of painting by moving the spray gun, changing the parameters (speed, distance, etc.), erasing and repeating any step of the process. He can also work in an automatic path generation mode. The result is a near-to-optimal path of the robot's tip (minimizing paint loss and providing a good evenness of coating).

Off-line programming of robots has a number of clear advantages over traditional ‘teach1’ methods which require the robot to be taken out of production. However, off-line programming techniques require extensive geometric facilities which are ideally provided by a geometric modelling system.

The use of modelling covers the planning of the robot workcell, as well as the detailed planning of the robot operations. Assembly, in particular, requires detailed geometric information concerning geometric features and solid properties.

The paper describes a newly developed three-dimensional computer animation system to be used for creating motion programs for a set of actors. The animation package includes a language for describing spatial motion of bodies, as well as an interactive tool to be used for assigning geometrical attributes to them and for guiding and visualizing the play-back of motion programs. One of the main uses of the package is robot programming and motion simulation. A geometrical modeller, which is a an aid in creating the models of animated bodies, is also described.

Computer simulation is a major tool in validation of robot motion planning systems, since, on the one hand, underlying theory of algorithms typically requires questionable assumptions and simplifications, and, on the other hand, experiments with hardware are necessarily limited by available resources and time. This is especially true when the motion planning system in question is based on sensor feedback and the generated trajectory is, therefore, unpredictable. This paper describes a simulation system ROPAS (for RObot PAth Simulation) for testing one approach — called Dynmic Path Planning (DPP) — to sensor-based robot collision avoidance in an environment with unknown obstacles. Using real time graphics animation of the motion planning system, the user can simulate the behavior of an autonomous vehicle or a robot arm manipulator with a fixed base. The overall structure of the system is described, and examples are presented.

Programming and control of industrial robots in a flexible manufacturing environment is a problem of increasing complexity. The paper deals with a software system, which is as much as possible independent of the real robot and suitable for different microprocessor configurations. It contains, furthermore, some components for off-line programming.

We present an analysis of currently available user language facilities for sensor-based programming of robot assembly tasks. A common criterion is defined that a language support for sensor-based programming must satisfy. Finally, drawing upon a novel mechanism of generalized exception, we present a framework for a complete solution of these problems in a high level block structured and complex language, as well as a possible implementation of such tools.

The optimum control of an industrial robot can be achieved by splitting the problem into two tasks: off-line programming of an optimum path, followed by an on-line path tracking.

The aim of this paper is to address the numerical solution of the optimum path planning problem. Because of its mixed nature, it can be expressed either in terms of Cartesian coordinates or at joint level.

Whatever the approach adopted, the optimum path planning problem can be formulated as the problem of minimizing the overall time (taken as objective function) subject to behavior and side constraints arising from physical limitations and deviation error bounds. The paper proposes a very general optimization algorithm to solve this problem, which is based on the concept of mixed approximation.

A numerical application is presented which demonstrates the computational efficiency of the proposed algorithm.

This work describes a hierarchically structured geometric database in an off-line robot programming system. The data structure contains the numerical definition of the frame variables, as well as an indicator of the respective reference frames. Moreover, the physical relations between the objects in the environment are included. The database is implemented such that it continuously reflects the actual structure of the environment. As a result, all calculations of the frame locations are carried out automatically. Moreover, the programming system is capable to autonomously updating the numerical information after changes in the environment. Making this database the heart of a robot programming system greatly simplifies the off-line programming of complex robot tasks, like f.i. assembly tasks.