Off‐line programming: a success for the automotive industry

In recent years, industrial robots have been introduced to various production sites through teaching playback, enabling more efficient assembly lines and welding lines for large workpieces in automotive and other industries. Furthermore, offline programming is expected to be utilized for cutting workpieces that are becoming even larger in the next-generation EV giga-cast and construction industries. However, the machining accuracy of robots, in terms of motion accuracy, is lower than that of machine tools, and their low rigidity causes vibration. Therefore, in this study, we attempt to construct a system for the practical cutting of large workpieces by attaching a DC brushless motor controlled by a single-board computer and drill to the end-effector of a large industrial robot and examining the basic characteristics of this system. The relationship between the rotational speed and duty ratio of the pulse width modulation voltage is clarified, and the range where the rotation speed is stable is found such that any rotation speed can be output. It is also clarified that the mechanical time constant of the rotational speed of the motor changes when the temperature of the motor spindle changes.

HELGA, a graphical simulation program of the IBM 7535 robot, uses animation to simulate the motion of the robot. A feature of HELGA is its off-line programming capability which has been designed specifically for use as an educational tool. Included in this paper are a description of the HELGA simulation program, some of its commands, and an example of the system's off-line programming capability.

In this chapter, we described the design and integration of a robotic welding cell using a 3D simulation environment. The design was useful for building the CORBA-based distributed robotized welding cell in this research project. Issues such as layout definition, communication design, welding part design, robot and welding station commissioning were considered. The design also included a voice-command driven environment using the Microsoft Speech Application Interface V5.0. Definition of Context Free Grammars were used so that it was possible to start a typical robot task using a human operator's voice using verbal commands such as "weld perimeter" or "weld trajectory". The design and simulation previous to the implementation of an automated welding cell is useful, because possible errors can be prevented such as problems of area distribution, security, dimensions, etc. In addition to its great utility to save costs and avoid unnecessary damage to machinery and equipment. The design of complex robot systems using multisensorial inputs, high-level machine interfaces and distributed networked systems will be elements is of primary importance for advance robot manipulators in the near future so that the work reported in this chapter intents to demonstrate alternative guidelines to design such complex systems.

SUMMARYThis paper presents an overview of several European projects whose common activity is the development of simulation tools and design methodologies for mechatronic systems in automotive and railway industry. It also covers some standardisation efforts taken place in these projects to provide with common languages, data formats and environments to develop mechatronic systems.

In the narrow and dangerous working environment, the welding robot is an important way to guarantee the welding quality and improve the welding efficiency. During the process of the welding, the robotic abilities of environment perception and 3D measurement are the premise of robotic automatic planning and automatic control, especially in the narrow environment. Because the laser sensor has the characteristics of compact structure, non-contact measurement and high precision, the laser sensor is used to design a new 3D measurement system of welding workpiece combined with the practical application requirements of aluminum electrolytic cell. This system combines off-line programming mode of the special welding robot in the virtual environment to achieve semi-automatic batch welding tasks. At the same time, a calibration method based on monocular vision is designed to calibrate the laser sensor. Through the experimental verification, the system can well realize the 3D measurement of welding workpiece. Meanwhile, the angle measurement error is lower than 0.5 degree. And the results meet the actual welding demand through the actual welding experiment verification.

Offline CAD-based Robot Programming and Welding Parametrization of a Flexible and Adaptive Robotic Cell Using Enriched CAD/CAM System for Shipbuilding

The engineering process of creating cell control systems is described, and a Cell Control Engineering (CCE) concept is defined. The purpose is to assist people, representing different disciplines in the organisation, to implement cell controllers by addressing the complexity of having many systems in physically and logically different and changing manufacturing environments. The defined CCE concept combines state-of-the-art of commercially available enabling technologies for automation system software development, generic cell control models and guidelines for the complete engineering process. It facilitates the understanding of the task and structure of cell controllers and uses this knowledge directly in the implementation of the system. By applying generic models CCE facilitates reuse of software components and maintenance of applications. In many enterprises, software makes up an increasing part of any production installation and in addition the software element is often very critical as it is the integrating, controlling and co-ordinating system component. As such, a CCE concept providing high quality and high functionality as well as flexibility is an important aspect of a company's automation strategy. The concept has been validated and verified at ODENSE STEEL SHIPYARD Ltd. in several robotic arc welding systems in the production using an application enabler, UNIX, X, SQL and (wireless) Ethernet. Integration with off-line programming, production planning, monitoring and maintenance has been achieved resulting in increased utilisation of the capability and capacity of the robot systems.

A knowledge-based multipass welding distortion estimation method for a multi-robot welding off-line programming and simulation software

COMPUTER-AIDED PROGRAMMING TOOL FOR ROBOTICS

The most widely used welding joining method in the automotive industry is resistance spot welding. Resistance spot welding (RSW) is the welding area where heat is produced by the effect of resistance against the flow as a result of exposing the welded parts to a local electric current. It has become an important issue to apply an effective approach method to guarantee weld quality and optimize welding parameters. This is of high value in theory and practice. In the literature, the effects of spot welding process parameters on the weld core diameter and electrode penetration depth are mostly investigated. Weld strength in RSW is affected by many process parameters such as applied electric current, compression force, welding time. Due to the contact resistance and joule heating, a molten weld nugget zone is formed on the work pieces. It is desirable to have the maximum temperature at the interface of the parts to be joined. In practice, the production of welds of acceptable quality depends on the definition of optimum weld parameters and the application of appropriate controls to ensure constant weld quality over a long production period. In the experimental studies, the optimization of the welding parameters was studied in order to obtain the maximum tensile-shear strength. The most prominent process parameters in experimental studies are electrode force, welding currents and welding times. Different algorithms have been developed for the optimization of welding parameters. The verification tests clearly show that it is possible to increase the tensile-shear strength of the connection with the combination of appropriate welding parameters. As a result, the experimental results confirm the validity of the algorithms used to improve welding performance and optimize welding parameters in resistance spot welding processes.

This article discusses the imperative for the creation of a new collaborative interuniversity master’s program in Industry 4.0 across three Moldovan higher education institutions. Development of such a new master’s program is the main goal of the ERASMUS+ project titled “EnhaNcing MEchanical Engineering EDUcation in Moldova for Industry 4.0/ NeedEDU4.0”. The proposed master’s program will be created and executed through partnerships between technical educational institutions and the industrial sector. Its primary focus is to equip future engineers in automotive construction with current knowledge and skills by integrating best practices from European Union university partners. The introduction of this modern joint interuniversity master’s program in mechanical engineering is anticipated to facilitate collaboration between universities and enterprises, to enhance the employability of graduates from mechanical engineering programs, thus enhancing regional development, cultivating lifelong learning skills, encouraging social innovations, and promoting inclusivity. Keywords: higher education, Industry 4.0, NeedEDU4.0 project, automotive industry, master’s program

Topology modeling is a challenging topic in the design and development of tools that simulate the behavior of interconnection networks. During the last years we have seen the birth of several simulation tools and frameworks modeling interconnects, some of them doing brilliant efforts to do the code re-usable and extensible. The main differences among these simulation tools and frameworks is the level of granularity and abstraction of their network models. Different network models may generate duplicated efforts in modeling certain aspects of them, such as the network topology or the routing algorithm. If the topology generation and routing algorithm modeling were separated from the modeling of other network aspects, then the simulator developers could focus on developing non-existing models and new functionality, without wasting time in doing a work previously done by other simulation tool developers. In this paper we describe TopGen, an external library that can be integrated with any tool that simulates interconnection networks. TopGen provides a compendious of well-known network topologies that can be used to interconnect the network components, such as end nodes, channels, switches and routers. It also provides the corresponding knowledge to apply a compendious of routing algorithms to the modeled network topologies. TopGen also supports the definition of customized topologies that are not the standard ones, thanks to a special interface used for this purpose. We also provide details on how to integrate TopGen with a network simulator, by means of a simple API. Finally, we describe several use cases of the TopGen library.

The way towards thermonuclear fusion simulators

The scaling up of a hydrothermal oxidation (HTO) facility depends on the development of simulation tools. In this way, a new approach to simulate the reactor thermal behavior during a nonstationary regime such as the start, stop, or emergency stop of the unit is developed. A numerical procedure of nonstationary temperature profile simulation in the reactor is described in order to predict the reactor thermal behavior. This new model is validated from experimental data obtained with a quasi-adiabatic reactor, which allows one to follow the temperature profile evolution along the reactor during the HTO process. Performances of the numerical procedure are tested with the simulation of three kinds of real nonstationary conditions: facility start, pump defect, and waste concentration dilution...

Progress on the Development of Generic Tools for Real-Time Simulation and Control of Complex Systems