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ABSTRACTEffective radiotherapy for cancer treatment requires precise and reproducible positioning of patients at linear accelerators. Assistance systems in digitally networked radiotherapy can help involved specialists perform these tasks more efficiently and accurately. This paper analyses patient positioning systems and develops new knowledge by applying the Design Science Research methodology. A systematic literature review ensures the rigour of the research. Furthermore, this article presents the results of an online survey on assistance systems for patient positioning, the derived design requirements and an artefact in the form of a conceptual model of a patient positioning system. Both the systematic literature review and the online survey serve as empirical evidence for the conceptual model. This paper thereby contributes to broadening the academic knowledge on patient positioning in radiotherapy and provides guidance to system designers.

The number and variety of paints and coating systems in the automotive industry have increased in recent years. However, the basic requirement for the quality of the paints still depends on the surfaces on which they are applied. This applies not only to the large body parts but also to all components that are integrated.

The influence of heat, developed in process, on the performance of bearings applied in rotational systems is often studied. In the present work, the influence of thermal expansion on the reduction of the radial clearance after assembly and the dynamics of the self-aligning ball bearing are experimentally studied. The course of the temperature change in the interior and exterior of the bearing was measured for several values of the radial clearance (RIC) and different rotational speeds. The results show a correlation between the temperature difference inside and outside the bearing and the clearance. Furthermore, it demonstrates the importance of the precise alignment of the clearance, as it was accepted.

The AIAG established the MSA, 4th Edition, as an international guideline to determine if the selected measurement system is capable and can be used for the intended purpose. The MSA guideline provides a practical basis for decision-making and is applied in both scientific and industrial contexts. In addition to the MSA, the Guide to the Expression of Uncertainty in Measurement (GUM) has standardized the determination of measurement uncertainties at an international level. This paper provides a practical example of using a surface comparator to demonstrate the limitations of the MSA for roughness parameters. Additionally, it presents a new method for assessing the capability of a measuring system for roughness measurements by considering the aspects from MSA and GUM. This work considers all information, distinguishing between existing and experimentally generated data. The experimental investigations for the application of the new method were carried out using a confocal laser scanning measuring microscope. The approach presents a new practical opportunity for both science and industry.

Flexibility and versatility in production put high demands on the planning, simulation and ramp-up of assembly systems and processes. For this purpose, a digital twin of a laser-based assembly assistance system for manual mounting tasks was developed, implemented and analyzed. A capability model was elaborated using quantitative and qualitative studies. The capability model was realized as a Unity 3D model. In the augmented reality implementation using the Microsoft HoloLens users can control the digital twin through hand gestures and voice control. The implementation shows that the digital twin of the laser-based assembly assistance supports the planning, simulation and training of employees at the shop floor.

A modular framework ensuring zero defect manufacturing developed for applications in different production processes was successfully tested on a polishing machine. Algorithms, predicting the optimal time to change the tools, were deployed to the framework and showed reproducible results under similar polishing conditions. Due to the modular software framework the algorithms, can be easily adjusted and changed, enabling the system to self-improve over time with minimal effort. The algorithms have been implemented into an embedded system.

The aim of this work is to develop a method for measuring radial clearance of bearings during the assembly process. A dedicated measuring device was developed. The clearance can now be measured before, during and after the process of mounting bearings. Furthermore, a corresponding intelligent algorithm developed within the frame of this work adapts to different bearing configurations, replaces the metrological identification of the test load. The curve progression of the test load was abstracted by a mechanical model and the characteristic curve correlated with the clearance. The sensor technology originally required could be replaced by an intelligent software system.

In this work, a method for measuring the radial clearance of bearings mounted on a shaft before and after assembling in an automatically and standardized way will be described. A setup was constructed, which enables to measure the radial clearance of different types of bearings with different dimensions. Tests with roller and ball bearings with tapered bore and adapter sleeves show that the developed system provides as good or better results than the manual test method. The results are reliable, objective, independent from the user and reproducible. Based on the results, the process of assembling could be readjusted. By using a closed loop method, it will be achieved that bearings will be mounted on a shaft with the specified radial clearance which is defined by the manufacturer of the bearing.

The aim of the work is to develop a method for measuring the radial clearance of mounted antifriction bearings in an automatically and standardized way. The measurement of the radial clearance should take place on bearings mounted on a shaft before and after assembling.

The dimensions of a workpiece have been measured during the milling process using a 3D laser inspection system. Re-clamping of the work piece has been avoided but a short interruption of the milling process took place. All three dimensions of the part have been measured, height and width using a profile scanning devise based on the laser triangulation method and the length using also the displacement features of the machine tool. Gauge blocks with the reference dimension of 4, 8, 10, 14, 18 and 23 mm have been used for the verification of the measurements. The measured values for the height deviate from the real value between 0 to 19 μm. The deviations of the length lie between 0 and 33 μm. The deviations of the width are higher and they lie between 0 and 150 μm, because of the scanning steps of the devise. The measurement of the width could be improved using a second scanner perpendicular to the first one in order to achieve an overall part inspection with deviations lower than 33 μm.