K Foit

The modular design of robotic workcells in a flexible production line

In the case of large-scale and mass production lines often the same model of an industrial robot is used in various places of the line and is intended to various task. However, the replacement of one industrial robot to another is a long lasting and arduous process. It requires stopping all the production line and sometimes even dismantling the whole workcell. Such situations are not frequent in production lines that are not flexible. They are related the most often with the failure on an industrial robot. However, during the designing of a flexible production line the ability to replace any robot, which is unrestricted, fast and trouble-free, greatly increase the flexibility level of such line. It could be realized by modular design of the proposed production line. In this way it could be possible to change any elements of such production system. But this approach needs to apply the specialized informatics system.This paper presents the obtained design of several versions of the same production workcell. Each, succeeding version of the designed production workcell contains more and more modular elements. Thereby it would be presented the evolution of a workcell design beginning from the typical design and ending with the fully modular one. One of tools needed to realize this task is the elaboration of a base of modules and typical joint and mounting elements that could be utilised in the described designing process. It is also presented the guidance information about the designing and programming processes useful at each stage of analysed process.

Modular industrial robots as the tool of process automation in robotized manufacturing cells

Recently the number of designed modular machine was increased. The term modular machine is used to denote different types of machinery, equipment and production lines, which are created using modular elements. Modular could be both mechanic elements, and drives, as well as control systems. This method of machine design is more and more popular because it allows obtaining flexible and relatively cheap solutions. So it is worth to develop the concept of modularity in next areas of application. The advantages of modular solutions are: simplification of the structure, standardization of components, and faster assembly process of the complete machine Additional advantages, which is particularly important for manufacturers, are shorter manufacturing times, longer production series and reduced manufacturing costs. Modular designing is also the challenge for designers and the need for a new approach to the design process, to the starting process and to the exploitation process. The purpose for many manufacturers is the standardization of the components used for creating the finished products. This purpose could be realized by the application of standard modules which could be combined together in different ways to create the desired particular construction as much as possible in accordance with the order. This solution is for the producer more favorable than the construction of a large machine whose configuration must be matched to each individual order. In the ideal case each module has its own control system and the full functionality of the modular machine is obtained due to the mutual cooperation of all modules. Such a solution also requires the modular components which create the modular machine are equipped with interfaces compatible one with another to facilitate their communication. The individual components of the machine could be designed, manufactured and used independently and production management task could be divided into subtasks. They could be also outsourced to an independent manufacturer. Standardization and run of the entire modular machine should be easier if standardized are individual modules. The advantages of modular design, in addition to those mentioned above, there are many more.

The distributed agent-based approach in the e-manufacturing environment

The deficiency of a coherent flow of information from a production department causes unplanned downtime and failures of machines and their equipment, which in turn results in production planning process based on incorrect and out-of-date information. All of these factors entail, as the consequence, the additional difficulties associated with the process of decision-making. They concern, among other, the coordination of components of a distributed system and providing the access to the required information, thereby generating unnecessary costs. The use of agent technology significantly speeds up the flow of information within the virtual enterprise. This paper includes the proposal of a multi-agent approach for the integration of processes within the virtual enterprise concept. The presented concept was elaborated to investigate the possible solutions of the ways of transmission of information in the production system taking into account the self-organization of constituent components. Thus it implicated the linking of the concept of multi-agent system with the system of managing the production information, based on the idea of e-manufacturing. The paper presents resulting scheme that should be the base for elaborating an informatics model of the target virtual system. The computer system itself is intended to be developed next.

Agent-based models in robotized manufacturing cells designing

The complexity of the components, presented in robotized manufacturing workcells, causes that already at the design phase is necessary to develop models presenting various aspects of their structure and functioning. These models are simplified representation of real systems and allow to, among others, systematize knowledge about the designed manufacturing workcell. They also facilitate defining and analyzing the interrelationships between its particular components. This paper proposes the agent-based approach applied for designing robotized manufacturing cells.

Construction typification as the tool for optimizing the functioning of a robotized manufacturing system

Process of workcell designing is limited by different constructional requirements. They are related to technological parameters of manufactured element, to specifications of purchased elements of a workcell and to technical characteristics of a workcell scene. This shows the complexity of the design-constructional process itself. The results of such approach are individually designed workcell suitable to the specific location and specific production cycle. Changing this parameters one must rebuild the whole configuration of a workcell. Taking into consideration this it is important to elaborate the base of typical elements of a robot kinematic chain that could be used as the tool for building Virtual modelling of kinematic chains of industrial robots requires several preparatory phase. Firstly, it is important to create a database element, which will be models of industrial robot arms. These models could be described as functional primitives that represent elements between components of the kinematic pairs and structural members of industrial robots. A database with following elements is created: the base kinematic pairs, the base robot structural elements, the base of the robot work scenes. The first of these databases includes kinematic pairs being the key component of the manipulator actuator modules. Accordingly, as mentioned previously, it includes the first stage rotary pair of fifth stage. This type of kinematic pairs was chosen due to the fact that it occurs most frequently in the structures of industrial robots. Second base consists of structural robot elements therefore it allows for the conversion of schematic structures of kinematic chains in the structural elements of the arm of industrial robots. It contains, inter alia, the structural elements such as base, stiff members - simple or angular units. They allow converting recorded schematic three-dimensional elements. Last database is a database of scenes. It includes elements of both simple and complex: simple models of technological equipment, conveyors models, models of the obstacles and like that. Using these elements it could be formed various production spaces (robotized workcells), in which it is possible to virtually track the operation of an industrial robot arm modelled in the system.

Determination of the robot location in a workcell of a flexible production line

Location of components of a manufacturing cell is apparently an easy task but even during the constructing of a manufacturing cell, in which is planned a production of one, simple component it is necessary, among others, to check access to all required points. The robot in a manufacturing cell must handle both machine tools located in a manufacturing cell and parts store (input and output one). It handles also transport equipment and auxiliary stands. Sometimes, during the design phase, the changes of robot location are necessary due to the limitation of access to its required working positions. Often succeeding changes of a manufacturing cell configuration are realized. They occur at the stages of visualization and simulation of robot program functioning. In special cases, it is even necessary to replace the planned robot with a robot of greater range or of a different configuration type. This article presents and describes the parameters and components which should be taken into consideration during designing robotised manufacturing cells. The main idea bases on application of advanced engineering programs to adding the designing process. Using this approach it could be possible to present the designing process of an exemplar flexible manufacturing cell intended to manufacture two similar components. The proposed model of such designed manufacturing cell could be easily extended to the manufacturing cell model in which it is possible to produce components belonging the one technological group of chosen similarity level. In particular, during the design process, one should take into consideration components which limit the ability of robot foundation. It is also important to show the method of determining the best location of robot foundation. The presented design method could also support the designing process of other robotised manufacturing cells.

Controlling the Movement of the Robot's Effector on the Plane Using the SVG Markup Language

In certain situations the robots effector must be moved strictly according to some path. The example of such case could be painting, cutting, milling, welding, glue applying etc. The common feature of the mentioned operations is that in the most of cases, the movement of the tool is realized on the plane. The advantage of use of a tool operated by a robot is that the work area could be placed anywhere in the manipulators workspace and can be set at almost any angle relative to ground. By specifying a local coordinate system, the operator can define the path of the tool. Referring to the earlier studies of the author, this paper continues the discussion of the possibility of using the markup languages in the field of robotics. The further part describes a proposal for the application of SVG markup language to describe the objects forming the path of a tool. Just like XML, the SVG code can be processed in many ways, giving the possibility of translation to the particular robots programming language. The described method has also some disadvantages arising from the purposes of the SVG standard, like the 2D nature of a path.

Analysis and Optimization of the Piston System Using CAD/CAE Engineering Environment

This article presents the approach to the problem considered with optimizing the stress distribution and functioning of a crankshaft system of a piston engine. One of possible methods of investigating such a problem is simulation of work of the analyzed mechanical system. This approach allows observing the work of a modeled system and improving the designed system. In this work was applied the PLM Siemens NX software. This advanced CAD/CAE/CAM environment let to model any complex system of a technical mean. Using this environment it is possible to model and analyze new solution, which allow significantly optimizing the functioning conditions of a piston engine. One of such a solution is the MDI system presented in the work.

Experimental determination of dynamic parameters of an industrial robot

In an industry increasingly used are industrial robots. Commonly used are two basic methods of programming, on-line programming and off-line programming. In both cases, the programming consists in getting to the selected points record this position, and set the order of movement of the robot, and the introduction of logical tests. Such a program is easy to write, and it is suitable for most industrial applications. Especially when the process is known, respectively slow and unchanging. In this case, the program is being prepared for a universal model of the robot with the appropriate geometry and are checked only collisions. Is not taken into account the dynamics of the robot and how it will really behave while in motion. For this reason, the robot programmed to be tested at a reduced speed, which is raised gradually to the final value. Depending on the complexity of the move and the proximity of the elements it takes a lot of time. It is easy to notice that the robot at different speeds have different trajectories and behaves differently.

Modelling of industrial robot in LabView Robotics

Currently can find many models of industrial systems including robots. These models differ from each other not only by the accuracy representation parameters, but the representation range. For example, CAD models describe the geometry of the robot and some even designate a mass parameters as mass, center of gravity, moment of inertia, etc. These models are used in the design of robotic lines and sockets. Also systems for off-line programming use these models and many of them can be exported to CAD. It is important to note that models for off-line programming describe not only the geometry but contain the information necessary to create a program for the robot. Exports from CAD to off-line programming system requires additional information. These models are used for static determination of reachability points, and testing collision. Its enough to generate a program for the robot, and even check the interaction of elements of the production line, or robotic cell. Mathematical models allow robots to study the properties of kinematic and dynamic of robot movement. In these models the geometry is not so important, so are used only selected parameters such as the length of the robot arm, the center of gravity, moment of inertia. These parameters are introduced into the equations of motion of the robot and motion parameters are determined.