UML design and AWL programming for reconfigurable control software development of a robotic manipulator

The goal of the presented research is to face the topic of reconfigurable control software development in a concrete fashion, i.e., by presenting a control software system development approach which has been used for a specific, although easy to be generalized, robotized manufacturing cell component. In particular, a methodology for the control software development of a planar robot (2-degrees of freedom) is presented, from the conceptual design to the actual implementation. The methodology suggests UAL and object-oriented modeling and programming techniques for the design phase, while AWL programming language run by a PLC for the implementation phase. The analysis has been conducted considering the internal and external requirements of the manufacturing system which comprises the. robot, mostly driven by the contemporary industrial need of reconfigurable control systems, critical key to succeed in the new era of mass customization

la responsibilità sciistica

In the context of the legal discipline of civil liability, the subject of continuous debate and evolution, this volume aims to provide a picture as complete as possible of ski liability by dealing with the different profiles of responsibility: managers of skiable areas, users, ski instructors, subjects involved in the organization of competitive events. This collection of conference proceedings, in addition to the contributions of the speakers, contains important works by scholars and experts in the field.; Nell’ambito della disciplina giuridica della responsabilità civile, oggetto di continuo dibattito ed evoluzione, il presente volume mira a fornire un quadro quanto più possibilmente completo della responsabilità sciistica trattando i diversi profili di responsabilità: dei gestori delle aree sciabili, degli utenti, dei maestri di sci, dei soggetti coinvolti nella organizzazione di eventi agonistici. Questa raccolta di atti di convegno, oltre ai contributi dei relatori, contiene importanti lavori di studiosi ed esperti della materia

A user-friendly control system to easy reconfigure a manufacturing cell

Generic manufacturing enterprises need to interact with an environment characterized by a strong competition. In order to react to the mutable requests of market, control systems should confer to the manufacturing system capabilities for easy modifiability, and this can be achieved by reducing the necessary time to reconfigure the existing system. Following this main requirement, this paper presents a user-friendly control system that pursues three operational goals: Ability to easy re-program the sequence of operations of the manufacturing equipments of a manufacturing cell; Reconfigurability of the system, by allowing to add/remove a new/existing component in/from the manufacturing cell. Real time supervisioning of the system, by the visualization of the currently executing operation and the state of each element of the cell. The proposed control system user-interface has been realized in Microsoft Visual Basic common programming language; by using such interface the operator can create the sequences of movements and operations of the elements without being acquainted with the different equipment control systems and their programming languages. The control system, realized in an object-oriented approach, allows the user to simply build up operation sequences by simply selecting step by step the specific manufacturing resource and the operation that the resource should execute. Every programmed operation will then be translated into the specific language of the controlled components which perform that operation. A case study shows how the proposed control system has been implemented in a real robotized manufacturing cell

Off-line Programming and simulation for automatic robot control software generation

In this paper an off-line programming approach for welding robots is presented. The approach is based on the integration of a software tool for robot simulation and an user-friendly interface for automatic generation of the control program. The user can graphically arrange the components in a robotic work-cell and simulate the movements and operations of robotic arms before converting motions and operating sequences in controller-specific tasks. This methodology guarantees high level of flexibility of the robotic system when high variety of work-pieces needs to be welded. The approach has been implemented and tested in a real welding work-cell

Improving Of The Productivity And The Quality Of A Manufacturing Robotized Cell For Mig/Mag Welding

During the last years, globalization and the necessity to reduce production costs have pushed industry to employ more and more manufacturing robotized cells. This trend has been assimilated by arc welding too. The use of robotic systems allows to increase the performance of productive systems by means of reduction in lead-time, reproducibility of processes and increase in quality. However, process automation needs pre-scheduling of manufacturing cell movements and also a setup of different welding parameters, such as power provided by the welding generator, arc length and robot speed, all of which allows to get a joint without defects. An online scheduling of robotic systems brings certainly a delay in production times, whereas offline scheduling allows to maintain the desired production without any production stop. An interface that allows to easily translate the coordinate points established by a simulation software (such as Robcad) in some complete programs that can be sent to the controller of the manufacturing cell, has been developed. Besides, in order to improve the joint’s quality, an analysis of the joint quality has been carried out by macrographic analysis. The employment of image analysis techniques on the obtained macrographs allowed to translate the morphology of each joint in terms of a matrix. After different morphologies have been distinguished in numerical terms and correlated to the joint’s quality, these data have been introduced as input to the interface. The output, constituted by the program for the controller of the cell and the best welding parameters, under such conditions, has allowed to increase both the cell’s productivity and the quality of the joints. Therefore, during offline scheduling, the initial phase of loop control of the joint morphology allows to evaluate the best welding parameters both in terms of productivity and joint quality. The same interface allows also to plan the best parameters for different welded joints with varying thickness and typology, which makes the system more eflexible and maintains a high level of productivity. The whole system has been implemented on a robotized cell GMAW Gas Metal Arc Welding Comau, that foresees a welding robot with six degrees of freedom and a position system with other six freedom degrees. Different T fillet joints have been realized at using of weathering steel sheets 5 and 6 mm thick

An Agile methodology for Manufacturing Control Systems development

Robotized manufacturing cells are required more and more often to process high variety of short life-cycle product. This increases the need for methods and techniques for easy reconfiguration of software programs running in Programmable Logic Controllers (PLC), i.e., devices able to control manufacturing systems. PLCs run embedded code characterized by a procedural nature that does not make it quite reconfigurable. In this paper we propose an AGIle COntrol System Development (AGICOSD) methodology that uses various practices of Agile software development methodologies and the Design By Contract (DBC) practice for modeling and programming manufacturing control systems. In this context we propose a way to automatically generate IEC 61131-3 conformed instruction list code starting from object oriented code and contracts written in Java Modeling Language. A test-bed and some industrial trials have shown the effectiveness of our methodology with respect to the traditional development methodology in terms of fast reconfigurability of manufacturing systems, reusability of instruction list code and reliable translation of java code to IEC 61131-3 standard compliant code