The article presents the structural and geometric synthesis and mechanical parameter choice for a manipulation mechanism for measurement microphone positioning during acoustical tests in anechoic chamber. Usually the aims of acoustical measurements in anechoic chamber are: noise source Sound Power Level estimation, electroacoustical transducer directional characteristics measurement, sound diffusing characteristic of a structure measurement, measurement of Sound Pressure Level on a given measurement grid The specific of that kind of measurements brings up the need of measurement microphone positioning in many points of the measurement space accordingly to relevant standards. In most cases during the tests it is necessary to position the microphone in certain points on the hemisphere. In such cases utilizing of typical microphone stands impedes the measurement and extends the time needed for the tests. Those circumstances led to idea of measurement manipulator construction that would allow changing the microphone position during the measurement accordingly to a specified algorithm. The following assumptions for construction were taken: measurement microphone moves on the hemisphere with a maximal radius of 2 m, the weight of transported object (microphone or other) does not exceed 1 kg, positioning accuracy is 1 mm. Structural and geometric synthesis was made taking into account mounting conditions in anechoic chamber in Department of Mechanics and Vibroacoustics AGH-UST. There were several variants labored that fulfilled the assumptions. The choice of particular solution was made based on: • manipulator drives possible installation analysis with regard to their acoustical noise emission • structure stiffness analysis with regard to assumed positioning accuracy of the microphone Finally a modular construction of manipulator was chosen, which is composed of industrial turntable (built in the level of the wire netting) and two linear motion modules (long axis, short axis). That solution means that the device under test fixed on the turntable rotates in the range of 2π, and the measurement microphone moves on the track of one quarter of a circle. Specific angular position of the linear modules was chosen which allows minimal dimensions of linear modules. Simultaneously the control structure and the software part are developed. The usefulness of the manipulator will be definitely confirmed by a research that should evaluate the influence of the construction elements on the acoustical free field in an anechoic chamber.

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Industrial robots are mostly designed for tasks where working conditions are well known and do not change over time. However, there are many examples where robots require vision sensor-based control in order to perform complex operations and react to changes in the environment. Other areas where there is need for combining vision sensors with manipulators are quality inspection tasks of large or complex structured objects. The paper presents an overview of the methods used in robotic vision systems, taking into account their specific requirements and advantages. Experimental studies of a selected 2D/3D sensors mounted on industrial manipulators are presented including analysis of collected 3D points clouds. Additionally, a system of a reconfigurable manipulator that interchangeably uses various sensors and tools in complex inspection tasks is presented.

For years now, the industrial manipulators have substituted human in many types of works during the manufacturing process. With robots the production rate increases, as does the quality of the product. The application of industrial manipulators increases the safety in the factories which in turn leads to savings. However, there are several difficulties in introduction of robotics into the production line. One of them is usually large cost of purchase and implementation of the robot. The proposed concept of the intelligent system for tool exchange is to address the stated issue. The aim of the system is to provide a mechanism for quick tool exchange supported by a decision making module that will constitute the self-reconfigurable industrial manipulator that is able to assess the situation at the production line, recognize the product and make decision on the operations to be performed, their sequence and which tool to use to perform that operation. Such a system of manipulator equipped with functions for reconfiguration and adaptation will be a solution for all applications where the production assortment changes quickly and is made in short series, and in particular for SMEs, which cannot afford purchase of several robots. They would buy one instead and let it perform variable tasks.The article briefly presents the concept of the hardware part of the exchange system, which includes both construction and the electronic modules for the tools, and concentrates on the concept of software expert system and database that allows intelligent decision making. The software control of the system is divided into four levels: the basic level, technical level, task level and procedure level. The basic level defines the movement of the robot such as: positioning, rotation, approach to the position etc. This level uses to control system of the applied manipulator and the data contained in the electronic modules of the tools. The basic level reflects the typical low-level control of the manipulator. The technical level defines the technical movement of the robot, small procedures related to the calibration of the tools, operation with the tool magazine (picking up and putting away) and related to tool maintenance – locking, unlocking, power supply, air supply and similar. The task level defines the operations related to the task performed on the object. Depending on the defined task the proper tool is selected (e.g. gripper, camera or a laser scanner) and, based on the data collected from sensors, performs the operation (e.g. scans the surface of the object). The highest level of control is totally independent on the hardware control system of the manipulator and the hardware of the robotic stand. Using the available databases and the recognition systems (e.g. cameras) makes decisions on what type of object appears on the production line and what operation is to be performed. The operations are defined as metacode that is interpreted and performed by lower control levels structurally bound to the control system of the manipulator.

The FSW method is a modern and still not very common method for joining materials by mixing them after plasticising with a special tool. The rotary motion of the tool and its pressure against the welded surface causes friction and, as an effect, local heating of the material that then causes plasticisation. Then the tool moves linearly along the trajectory of welding, while the stem causes the mixing of materials and tool’s shoulder concentrates and presses the material in the produced weld. An important feature of the process is that the material does not pass to the liquid phase and remain in the solid phase. This method allows the combination of non-welding and difficult to weld materials, including combining different materials (dissimilar). The FSW method is a new method and there are no tools to assess the quality of the process, especially on-line, that is in the making of the weld. Currently, the research methods used include point temperature measurement and measurement of forces on the tool performed during welding, and metallographic methods that are destructive can be used after the weld. This article presents the authors’ method for monitoring the Friction Stir Welding (FSW) processes with use of a multi-spectral vision method. The monitoring method uses the system built of two visual channels that work in different light bands; hence, the name of the method ismulti-spectral.The main component of the system is an infrared camera that is used for the observation of the temperature distribution on the surface of the welded materials. The second visual channel uses the line-scan visual band camera for recording the image of the surface of the weld. Such observation allows the detection of weld defects and non-compliances, which include excessive burrs, discontinuities, uneven edge of the weld, as well as the subsurface faults such as cavities and sub-surface discontinuities. In addition, the temperature of the process is monitored to prevent under-and over-heating, which may result in a weak joint or cracks in the material. The presented method is applied for monitoring the FSW process and presents a worldwide novelty.