Tim Sadek

Modelling Approach for the Integrated Development of Industrial Product-Service Systems

Shifting business focus from offering mere physical products to offering IPS2 an innovative strategy to meet customer requirements is revealed. The objective of this paper is to present a modelling approach for integrated development of IPS2-concepts in early development phases. The characteristics of the IPS2 concept modelling approach are deduced from a case study on a fictitious micro-manufacturing task. The proposed modelling approach abolishes established and mostly diffuse borders between products and services to assess systems behaviour already in early phases. Furthermore, applying the concept of modularisation to services in order to reduce complexity induced by specific IPS2-characteristics is discussed.

A Methodology for the Development, Production, and Validation of R-Phase Actuators

The R-phase transformation has interesting features with potential for applications that need a small temperature hysteresis and good dynamic behavior, such as thermostatic valves. The aim of this article is to show the development, production, and validation process of different R-phase shape memory alloy (SMA) actuators, starting with a semi-finished wire and concluding with a finalized R-phase spring actuator. This study focuses mainly on the calculation, the thermomechanical treatment, and experimental validation of the designed actuators. The first section of this article presents a mathematical dimensioning tool for different R-phase actuators, especially for extension SMA springs. The second part shows specific parameters on the R-phase transformation during thermomechanical treatment. The parameters Ni-content and annealing temperature are being varied to achieve different transformation behavior of the R-phase. The third section relates to the production process of calculated SMA spring actuators based on the R-phase transformation. In the fourth and last section of the article, the performance of selected actuators will be characterized in functional tests, and the results will be compared with the calculated results of the mathematical model.

Eine modellorientierte Methodik zur Unterstützung der Konzeptentwicklung industrieller Produkt-Service Systeme

Industrielle Produkt-Service Systeme (IPS2) sind durch eine lebenslauforientierte Integration von technischen Produkten der Investitionsguterindustrie und industriellen Services gekennzeichnet. IPS2 konnen aus einer beliebigen Kombination von Produkten und Dienstleistungen gebildet werden. Nach der Planung eines Leistungsangebotes ist es nunmehr Aufgabe der IPS2-Konzeptentwicklung, eine prinzipielle Losung zu generieren, die kundenspezifische Anforderungen erfullt. Basierend auf der heterogenen IPS2-Konzeptmodellierung wird in diesem Beitrag ein flexibler methodischer Ansatz prasentiert, der in der fruhen IPS2-Entwicklungsphase angewendet werden kann. Hierzu werden zunachst essentielle Grundlagen von IPS2 erlautert. Nachfolgend werden der heterogene Modellierungsansatz charakterisiert und die wesentlichen Bestandteile dieses Ansatzes vorgestellt, mittels dem eine integrierte Beschreibung von IPS2-Konzepten erfolgen kann. Im Anschluss werden die Methodenbausteine der modellorientierten IPS2-Konzeptentwicklungsmethodik erlautert und anhand eines Anwendungsbeispiels aus der Mikroproduktion verdeutlicht.

Knowledge Based Assistance for Conceptual Development of Industrial Product-Service Systems

The conceptual development of Industrial Product-Service Systems (IPS2) requires the integration of different domains, i.e. mechatronic and service engineering. Considering this integration, an IPS2 concept model and an IPS2 concept development methodology have been proposed. Applying model and methodology to an evaluation example reveals that even simple IPS2 can reach a high level of complexity in the conceptual design phase. To handle this complexity and to optimise the development of IPS2 concepts, developers need comprehensive knowledge of participated domains and effective development tools. In this paper an approach for a knowledge based assistance is presented, which supports developers in different tasks of IPS2 concept development. Focus of the paper is the knowledge based support of the IPS2 concept development methodology by deducing concepts for IPS2 from given requirements. Starting with the basic understanding of IPS2 concept modelling and conceptual development, the paper describes the requirements for a knowledge based assistance system. Based on these requirements, an approach has been developed and implemented in a software prototype. This paper concludes with the application of the approach on an evaluation example.

Traditional and project- and team-based education in mechatronic and robotic systems design

Basically, education in engineering design has to focus, on the one hand, on impartment of theoretical knowledge as well as, on the other hand, on gaining practical experiences. But additionally, teaching and education has to adequately cope with the fact that technical products and systems are becoming increasingly multidisciplinary. Best examples are mechatronic and robotic systems. Such products can effectively be developed only by a team of engineers and designers. The involved team members mostly have different background, knowledge and experiences. Consequently, already during their education students have to be adequately prepared for team-based work to be able to understand, communicate and work with the other team members. Hence, distinct team and soft skills gain significant importance. This paper reports on our educational concept combining traditional and advanced methods to gain, on the one hand, systems- and subject-related as well as, on the other hand, practice-related, personal and social competency. At its core are small-scaled design-and-build projects standing out due to their integrated approach.

Controlled Maneuverability of an Articulated Tracked Mobile Robot

Considerable potentials with regard to mobility in unstructured environment offer actively articulated mobile robots equipped with powered wheels or tracks. These potentials are obvious when dealing with a system’s trafficability and terrainability. However, maneuverability and steerability of articulated mobile robots are challenging. This is due to the fact that these robots represent a form of truck-trailer systems leading to interactions and influences between the individual vehicles resulting in significant problems like e.g. off-tracking with regard to a given path. Further on, when dealing with a mobile robot’s maneuverability there are only few scientific contributions covering articulated vehicles with actively powered trailers using tracks as propulsive elements. The described systems differ significantly with regard to their configuration with respect to the multi-redundant mobile robot in this work. To investigate the maneuverability of articulated tracked mobile robots a demonstrator has been developed. It is built up out of three identical modules which are connected with each other in a rowby means of a rotational and a translational degree-of-freedom. Each module has two tracks which can be powered independently. Overall, the system has got ten degrees-of-freedom whereas six of them are active and four passive. The developed demonstrator has been used for investigations dealing with maneuverability and steerability as well as modularization of the system’s control architecture. The paper summarizes the development of the mobile robot, its feedback control strategy as well as the tests carried out. The achieved results show a satisfying performance with regard to the implemented control strategy and the system’s maneuverability.Copyright

Sach- und dienstleistungsintegrierte Konzeptentwicklung

Im Anschluss an die HLB-Planung besteht die Aufgabe der HLB-Konzeptphase darin, prinzipielle Losungen fur ein hybrides Leistungsbundel zu entwickeln. Um die individuellen Kundenanforderungen an ein HLB nutzenmaximierend zu erfullen, ist bereits in der HLB-Konzeptentwicklung eine Berucksichtigung der Wechselwirkungen zwischen Sach- und Dienstleistungsanteilen erforderlich. Bisher existieren nur wenige modellbasierte Ansatze, die speziell einem Entwickler bei der sach- und dienstleistungsintegrierten Konzeptentwicklung zur Verfugung gestellt werden konnen. Um auf diesen Bedarf einzugehen, wurde ein IT-gestutzter Ansatz zur Modellierung von HLB-Konzepten entwickelt, der in diesem Beitrag vorgestellt wird. Hierzu wird zunachst die Stellung der HLB-Konzeptphase innerhalb des HLB-Entwicklungsprozesses erlautert. Nachfolgend werden die wesentlichen Bestandteile des HLB-Konzeptmodellierungsansatzes vorgestellt. Im Anschluss wird das prototypische realisierte Softwarewerkzeug zur integrierten HLB-Konzeptmodellierung erlautert und anhand eines Anwendungsbeispiels aus der Mikroproduktion verdeutlicht.

Analyzing the Practical Usability of the Heterogeneous Modeling Approach for Conceptual Product-Service System Development

Product-Service Systems are characterized by the integration of technical products and services along their lifecycle. To generate principle solutions of a PSS that meet customer-specific requirements, it is important to consider interdependencies between products and services already at an early phase of development. Thus, a suitable model-based approach for conceptual PSS development has been developed. Due to the complexity of this modelling approach, deficiencies regarding its practical usability could be revealed. This contribution aims at presenting initial requirements and optimization objectives concerning the practical usability of the modelling approach. Therefore, two PSS scenarios with practical relevance have been analyzed.

Wheeled, Kinematically Redundant Locomotion System for Mobility-Oriented Research and Experimentation

Mobile robots for inspection and surveillance of hard-to-reach and hazardous areas e.g. resulting from a building collapse in the course of a natural or man-made catastrophe have to possess enhanced rough terrain mobility capabilities. First, they must be able to navigate through a given environment and to avoid insurmountable obstacles. Second, they must have the ability to traverse different forms of ground without getting immobilized by a loss of traction. Third, they must be able to negotiate a wide spectrum of obstacles including e.g. wide gaps and high steps. These abilities can be described as a mobile robots performance indices “maneuverability”, “trafficability” and “terrainability”. As a consequence, mobile robot concepts for disaster control and search-and-rescue tasks always have to be developed and evaluated with regard to these performance indices. In principle, considerable potentials with regard to mobility in unstructured and rough environments offer kinematically redundant locomotion systems equipped with powered wheels or tracks which are inspired by their biological archetype snake. These potentials are based on the systems’ snake-like; modular design as well as their given kinematic redundancy. Due to their slender, modular and flexible design the systems are basically able to travel and maneuver through noticeable narrow passes and tunnels. Further on, their kinematic redundancy can be used for a purposeful posture and terrain adaptation to safeguard traction and the system’s trafficability, respectively. Finally, the systems’ modular and articulated design, both, can be used to achieve an outstanding terrainability and to be able to negotiate remarkable obstacles. The described and expected potentials of kinematically redundant locomotion systems have to be investigated in detail as well as evaluated in practice. To be able to do so, a demonstrator has been developed and implemented for intense mobility-oriented research and experimentation. The mobile robot and first experimental results are described in the paper at hand. The system stands out especially due to an innovative sensory for slip and contact force detection.Copyright

Adaptive Resetting of SMA-Actuators

Shape Memory Alloys (SMAs) have essential advantages compared to conventional actuators, in particular their high power density and their silent mode of operation. However, this material has not gained acceptance in technical applications yet. The main reasons are the missing simulation tools and a lack of knowledge of materials as well as the companies’ uncertainty how to handle SMAs. The resetting of the SMA element to generate a repeatable movement is often a defined problem. In this context reset springs made of steel are conventional solutions although their characteristics are a disadvantage. To reach a high level of power output and hence a high degree of efficiency, a reduction of the pre-load is necessary. A solution for this problem is an adaptive resetting. One main possibility to generate an adaptive resetting is given by the agonist-antagonist principle where two SMA-elements work against each other. Here the reset force can be applied if necessary. The advantage of this type of design is that a conventional return spring or a mechanical brake for clamping the position (electrically operated) is not necessary. Another possibility for adaptive resetting is to change the spring characteristics of a pseudoelastic SMA-element by heating. The aim of this study is to show the properties of the agonist-antagonist design and the other concepts. It also provides methods and the knowledge to support the development process of such resetting principles. The development of these methods is based on the analysis of different designs and requirements. Based on the results, instructions for the conception of adaptive resetting systems have been created.Copyright