In order to fully exploit the potential of the rapidly progressing digitalisation of technical systems, it is necessary to provide reliable and significant process and condition related data. In this context, solutions are especially aspired to allow a simple integration into the surrounding system and to influence it as little as possible. The main challenges regarding the measurement of process and condition data in the operation and control of technical systems as well as in test environments are identified and presented at the beginning of this article. A promising approach to meet the resulting requirements is the integration of sensory functions into simple standardised machine elements. In order to facilitate the discussion and interdisciplinary development of machine elements with sensory functions, an extension of the existing classification of mechatronic machine elements is introduced and illustrated with examples. The introduced classification takes into account the classification according to Stücheli and Meboldt and is based on a comparison of conventional and mechatronic machine elements on a functional level with regard to the function structure. As a result, the three classes sensor carrying machine elements, sensor integrating machine elements and sensory utilizable machine elements are introduced and subsequently discussed in more detail on the basis of examples. Finally, an outlook is given on the main research areas with regard to the development of mechatronic machine elements. Key aspects include working principles and effects for application in mechatronic machine elements, system analysis with regard to load conditions, power supply of sensor and data processor in the environment of the machine element as well as data processing and signal transmission under typical environmental conditions of mechanical engineering.

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The importance of considering disturbance factors in the product development process is often emphasized as one of the key factors to a functional and secure product. However, there is only a small number of tools to support the developer in the identification of disturbance factors and none of them yet ensures that the majority of occurring disturbance factors is considered. Thus, it is the aim of this contribution to provide a tool in form of a control list for the systematic identification of disturbance factors. At the beginning of this contribution, the terms “disturbance factor” and “uncertainty” are defined based on a literature review and different approaches for the classification of uncertainty are presented. Subsequently, the fundamentals of multipole based model theory are outlined. Moreover, a first approach in terms of a control list for a systematic identification of disturbance factors is discussed. Based on the discussed approach and taking the identified weaknesses as a starting point, a control list is presented that combines the existing basic concept of the control list with the fundamentals of multipole based model theory.

Close to process measuring improves the data quality of a condition monitoring process. A possibility to access such measurements comes with the addition of a sensory function in machine elements. For a systematic development of sensing machine elements, an approach is presented for the identification of possible measurands to determine a variable of interest. Based on a modelling of physical causeeffect- relationships by using an effect matrix and an effect catalogue it allows to consider both direct and indirect measurements for the determination of measurands in technical systems.The presented approach is initially applied to develop a sensory solution for self-lubricated fibrecomposite sliding bearings. The aim is to measure a variable of interest that can give a conclusion about the estimated remaining useful lifetime. The development process is described and possible solutions for measurement concepts are presented. The electrical capacity measurement, evaluated as the most promising concept, is described in detail and experimental results are presented.These results show the applicability of the sensory concept and therefore, the benefits of the presented approach.

A mandatory requirement for the concept of intelligent systems and of digital or cyber-physical twins is the availability of high-quality data. Therefore, the authors investigate the possibility to integrate sensors, actuators and information technologies in standardized machine elements such as screws, bearings and couplings. In this paper, the focus is on sensing machine elements, which are a sub-category of mechatronic machine elements. To gain insights about those in development as well as to verify and validate their functionality, prototypes are needed. Those prototypes should help the designer to gain knowledge about the product in development and they should preferably be developed with low efforts. Therefore, a method is proposed to analyse concepts of mechatronic machine elements, especially sensing machine elements, regarding critical aspects that may interfere with the functionality of the product. The method is based on analysing the flow of the signal that is used for the measurement, starting from its mechanical origin and ending at the analysis unit. Different examples of sensing machine elements are given in this article and the respective flow of the usable signal is analysed, leading to the identification of subsystems that can be tested individually. Based on this, prototypes for the subsystems are developed and introduced.