Kirsten Tracht

Universität Bremen | Uni Bremen · Department of Production Engineering

Production of complex and large-dimensioned goods in small lot sizes is a demanding task. To provide an adequate level of flexibility, multi-variant assembly operations are often executed manually by skilled workers. Human-robot collaboration can support workers by performing physically or psychologically stressful tasks. Existing procedures on tas...

The implementation of plug and fly principles for the assembly of high-lift systems requires the design of new work processes and jigs. Conventional jigs are inflexibly and lag of capabilities to adapt for product and process designs. Adaptive jigs provide higher flexibility and allow workers to position the product in accordance with their persona...

Tool wear and the decision when to replace tools is a universal challenge in the metal cutting industry. While the tool wear state can be accurately determined using optical measuring methods, the tool wear of milling tools is often examined by the CNC-machine operators, especially in small and medium enterprises. In order to increase the accuracy...

Once on Mars, maintenance and repair will be crucial for humans as supply chains including Earth and Mars will be very complex. Consequently, the raw material available on Mars must be processed and used. Factors such as the energy available for material production play just as important a role as the quality of the material that can be produced an...

Once on Mars, maintenance and repair will be crucial for humans as supply chains including Earth andMars will be very complex. Consequently, the raw material available on mars must be processed and used. Factors such as the energy available for material production play just as important a role as the quality of the material that can be produced and...

Fuel Cells (FC) are one of the most promising technologies for achieving the European climate targets, especially for future mobility. As part of the German government's national hydrogen strategy, measures for the further development and implementation of FC technology as a drive technology in automobiles as well as the production and use of hydro...

The handling of delicate spherical microsamples for applications in research and development requires a technique that does not damage or influence the sample. A particularly gentle grasping method is the grasping with dry-adhesive microstructures. A dry adhesive structure is holding the object passively, so there is no external influence to upkeep...

Image based classification enables the acquisition and transfer of data from manual assembly workstations into a digital environment. Based on the Methods-Time Measurement method, assembly processes are transformed into short, discrete basic operations that are recognised by means of image processing and used as input data for a multilayer neural n...

Despite increasing automation in manufacturing and assembly, production without humans is unlikely in the future. Instead, human-robot collaboration will play a central role with regard to future assembly processes. The accompanying changes in tasks require corresponding vocational training and continuing education measures for competence developme...

Virtual reality offers new opportunities in production education and training. The simulation of haptic perception is, however, still an ongoing topic of research. This paper describes the development of a simple tool replica to simulate different hand-held tools out of the production. Different attributes like shape, weight and functionality of th...

Virtual reality offers new opportunities in production education and training. The simulation of haptic perception is, however, still an ongoing topic of research. This paper describes the development of a simple tool replica to simulate different hand-held tools out of the production. Different attributes like shape, weight and functionality of th...

Visual sensor data of manual assembly operations offers rich information that can be extracted in order to analyze and digitalize the assembly. The worker’s interaction with tools and objects, as well as the spatial–temporal nature of assembly operations, makes the recognition and classification of assembly operations a complex task. Therefore, cla...

The assembly of products is often supported by jigs. Especially for large dimensional products, jigs and fixtures are used to align the components and ensure the stability of the assembly until all parts are firmly mounted. This paper describes the development of mobile, modular and adaptive assembly jigs, which are designed to support ergonomic wo...

Image processing enables the acquisition and transfer of data from manual assembly work spaces into a digital environment. The following paper addresses the question to what extent processes of manual assembly can be reliably derived from visual sensor data and classified by machine learning algorithm. Complex assembly processes are transformed int...

Micro systems technology is one of the key enabling technologies of the 21st century [Hes03], with increasing relevance due to a general trend towards miniaturisation in many industries. The main boosters for this trend are currently the consumer and communication electronics market and—to a lesser extent—medical technology (especially microfluidic...

The design of micro production processes and systems faces a variety of significant challenges today. This is due both to economic and to technological challenges. Generally speaking, in most industries micro production tends to be characterized by mass production, meaning very high lot sizes from several thousands (e.g. in medical technology) to l...

In the course of increasing automation and individualization of products, so-called collaborative robots (Cobots) play an increasingly important role. The systematic automation of manual assembly by adding automation components enables efficiency and cost advantages to be realized without the loss of flexibility. Previous industrial robots are not...

Sustainable production systems are characterized by systematic order control and scheduling to increase performance. Efficient scheduling considers all restrictions that occur during order processing, to achieve high utilization. This includes safety margins for ad hoc changes and in particular the scheduling of temporarily paced sequences. After p...

The use of physical mock-ups offers the possibility to evaluate the efficiency of assembly processes in early design stages of product development. Therefore, the challenges of assembly procedures, which arise during the implementation of new large-dimension assembly groups, can be managed prematurely. Assembly training with a derivative product in...

The interaction of human and machine in assembly, as applied in collaborative robotic systems, offers a great potential for a higher flexibility of production systems and the individualization of assembly operations. In order to make collaborative assembly systems save for workers that are not trained in programming and operating robotic systems, a...

Human-robot collaboration is a key technology for realising and optimising the assembly of multi-variant products. However, the long-term and economic operation of collaborative systems requires eligible methods for the consolidation of lifecycle information and the transfer of operational and product data from the shop-floor into planning systems...

The use of elementary production technologies allows to shift the knowledge and the effort of the design of manufacturing processes from the producers and towards the system manufacturers. Therefore, it enables urban producers that do not have complex process knowledge to implement robust and versatile process chains. This facilitates the utilizati...

Customized production and provision of tailor-made services are common business models in globalized production. These can be found for example in materials research by means of high-throughput systems and the overhaul of spare parts. In both cases, there are warehouses and buffers with different requirements and limited capacity in the systems. Th...

This Open Access proceedings presents a good overview of the current research landscape of industrial robots. The objective of MHI Colloquium is the successful networking at both academic and management level. Thereby, the colloquium focuses an academic exchange at a high level in order to distribute the obtained research results, to determine syne...

For the handling of samples for material testing, a gentle grasping method is necessary. While scaling effects in the micro domain typically pose a challenge for handling, an adhesive grasping system based on an artificial microstructure can utilize the Van-der-Waals force to advantage. For the design of a dry-adhesive grasping system, it is necess...

For precise and complex handling tasks, it might be necessary to measure forces that act on the handling object and the gripper respectively. Additional sensor modules decrease the remaining payload of the manipulator. By attaching strain gauges on the gripper fingers, the fingers themselves become force sensors. Several scientific publications and...

Sustainability is an important goal of today’s companies. The connectivity and decentral production are challenges while aiming at the reduction of CO2 pollution. For a higher utilization of transportation capacities, it is crucial to bundle freights cross-companywide. Therefore, the idle capacities of lots of transport companies must be notified c...

High-throughput screenings are established evaluation methods in the development of functional materials and pharmaceutical active ingredients. The transfer of this approach to the development of structural materials requires extensive adaptations. In addition to the investigation of new test procedures for the determination of material properties...

Deutschland ist im Weltmaßstab eine bedeutende Industrienation. Bei der Herstellung komplexer Industriegüter hat die Montage einen entscheidenden Anteil an der Wertschöpfung. Vor diesem Hintergrund hat das Bundesministerium für Bildung und Forschung (BMBF) im Jahr 2015 den Ideenwettbewerb „Kompetenz Montage – kollaborativ und wandlungsfähig“ ausge...

Der MHI e.V. ist ein Netzwerk leitender Universitätsprofessoren aus dem deutschsprachigen Raum, die sowohl grundlagenorientiert als auch anwendungsnah in der Montage, Handhabung und Industrierobotik erfolgreich forschend tätig sind. Die Gründung der Gesellschaft erfolgte im Frühjahr 2012. Der MHI e.V. hat derzeit 20 Mitglieder, die über ihre Instit...

Manual assembly is typical for complex products with large-scales and low repetition rates. The assembly control is usually realized by supervisors and claims a large part of their working time. The approach for decentralized assembly control is used for relieving the supervisors and for making the assembly process more efficient. In case of statio...

Die Handhabung von sphärischen Mikroproben stellt besondere Anforderungen an die Handhabung, aufgrund von Geometrie und Größe der Proben. Die Nutzung der Adhäsionskräfte, welche die Handhabung kleiner Teile in vielen Fällen erschweren, lassen sich hier vorteilhaft einsetzen. Eine Möglichkeit diesen Effekt zur gezielten Nutzung zu verstärken, beruht...

Kurzfassung Im Sondermaschinenbau sind viele Montagen als Gruppenmontage organisiert. Durch die steigende Komplexität der Produkte bei gleichzeitiger Produktindividualisierung sind die Verantwortlichen in der Montage zunehmend nur mit der Steuerung beschäftigt. In diesem Beitrag wird ein Ansatz zur dezentralen Montagesteuerung auf die Gruppenmontag...

The manufacturing of linked micro parts simplifies the handling and facilitates a consideration of trends due to the maintaining of the manufacturing order. These known changes of geometrical characteristics of parts are the basis for softening tolerances. The basic idea of the tolerance field widening is familiar with selective assembly. Instead o...

High-throughput screenings are widely accepted for pharmaceutical developments for new substances and the development of new drugs with required characteristics by evolutionary studies. Current research projects transfer this principle of high-throughput testing to the development of metallic materials. In addition to new generating and testing met...

In micro production, small tolerances, as well as size effects increase the requirement for a fast, precise, and reliable methodology that enhances the output of assemblies. In contrast to conventional approaches, a widening of the tolerance field enables an overall improvement of the output of a process chain while assuring functionality of parts....

Augmented reality as a technology for programming a collaborative robot is in comparison to existing practice a more intuitive, safe and quick approach. This paper shows a novel concept for connecting a physical robot with its virtual twin, using augmented reality as a visual output and a device for interacting with the simulation model. The core o...

Fast time to markets becoming increasingly important through dynamic product life cycles. An assembly planning in early project stages is necessary, which evaluates assembly procedures and the mountability. The use of derivative products offers this possibility since the simplified form can be used for examining important steps in assembly processe...

A collaboration between human and robot can implicate many advantages for complex industrial assembly processes, especially as increased flexibility and adaptability become a key feature of production systems. The use of virtual reality (VR) systems has the potential to simulate cooperative processes in advance and to include workers and their indi...

Production processes with small tolerances are still challenging the industry. The increasing competitive pressure raises the necessity of economically efficient processes. Assembling parts while considering part-specific clearance enables a widening of the tolerance field by considering trend specific clusters and matching. Two or more otherwise r...

Material testing in high-throughput systems facilitates a fast, precise and innovative method for the identification of metals with required characteristics. This material testing setup leads to highly flexible material flow between test stations similar to job shop fabrication. Various requirement specific test plans and the occurrence of temporar...

A modular assembly system is introduced for obtaining a high flexibility which consists of manual work stations and collaborative robot modules that can be individually arranged and connected, dependent on the actual process requirements and qualifications of workers. The modularization induces a fast adaption towards different product variants and...

An assembly planning parallel to the product development allows to identify the arising assembly challenges and their resulting requirements at an early stage. However, a reliable planning of assembly for large-volume assembly groups is difficult, as the implementation of assembly for new products is characterized by recurring optimization phases u...

The maintenance of large-scale products such as aeroplane engines or aeroplanes take place stationary. Due to the complexity of those products, the coordination of the workers is a large effort for the responsible people. This article presents a method for decentralised resource control in maintenance shops with stationary products. Therefore, an e...

Das Speichern ist ein essenzieller Prozessschritt bei der Fertigung von Mikrobauteilen im Teileverbund. Um eine plastische Verformung der Verbunde auszuschließen, wird in Wickelprozessen Zwischenmaterial zum Schutz von Bauteilen eingebunden. Aus der Funktionsstruktur dieses Prozesses wird ein morphologischer Kasten abgeleitet, um systematisch Speic...

Metal forming and joining of micro components is related to a high number of requirements. Especially small manufacturing tolerances, scaling effects and mechanical handling efforts are still challenging. Due to these factors, production processes from macro components cannot be transferred easily to micro range. One way to address these issues is...

For speeding up the development of new metallic materials, the collaborative research centre SFB1232 ‘Farbige Zustände’ researches a highthroughput method for material testing. This approach aims at generating metal spheres smaller than 1 mm in diameter, and applying different thermal and mechanical treatments on them. Afterwards the samples are in...

Der MHI e.V. ist ein Netzwerk leitender Universitätsprofessoren aus dem deutschsprachigen Raum, die sowohl grundlagenorientiert als auch anwendungsnah in der Montage, Handhabung und Industrierobotik erfolgreich forschend tätig sind. Die Gründung der Gesellschaft erfolgte im Frühjahr 2012. Der MHI e.V. hat derzeit 20 Mitglieder, die über ihre Instit...

Assistenzsysteme werden in der manuellen Montage vielfältig eingesetzt. Dieser Artikel stellt ein System vor, das Assistenzfunktionen zur kollaborativen Zusammenarbeit von Mitarbeiter und Roboter in ein Steuerungsprogramm integriert. Dieses umfasst eine Mensch-Maschine-Kommunikation, eine Adaption an den Mitarbeiter, ein Teach-In und eine Fortschri...

Die schnelle Entwicklung von metallischen Konstruktionswerkstoffen in einem Hochdurchsatzsystem bedarf aufgrund prozessinhärenter Restriktionen neuer Verfahren zur Planung und Steuerung. Prozessflexibilität, strukturelle Änderungen sowie Wiederholprüfungen sind ursächlich für eine hohe Komplexität, die zur Durchsatzsteigerung bereits in der Belegun...

Rotor blade carriers are custom build for each wind turbine rotor blade type. This causes high efforts in design processes, assembly preparation and raises the number of product variants. This paper presents an approach to apply the concept of modularisation on rotor blade carriers to induce serial production methods, optimise the easiness of assem...

High-Throughput Systems (HTS) are utilised predominantly in pharmaceutical and food industry as well as medical technology. Those rigidly linked systems with large outputs of up to 100,000 samples per day are used for screening or synthesis. The usage of HTS enables major increases in quantities and decreases in throughput time. With regard of test...

Learning Factories are implemented for multiple applications offering opportunities for practical research and training. The majority of learning factories is designed for very special purposes as training of lean methods and manufacturing logistics. The bime developed and installed an adaptable Learning Factory called BERTHA that is capable to run...

The digital progress monitoring of manual assembly processes at goods with huge dimensions is a challenging task. The paper presents an approach using 3D-image sensors for gesture control and progress recognition. The developed system is able to avoid time and effort consuming walks of workers between assembly objects and computer terminals. Progre...

High value and long life products require continuous maintenance throughout their life cycle to achieve required performance with optimum through-life cost. This paper presents foundations and technologies required to offer the maintenance service. Component and system level degradation science, assessment and modelling along with life cycle ‘big d...

A central challenge of micro forming production is the handling of component parts. The simple transformation from macro to micro scale of the forming and handling processes is complicated due to size effects. One solution for overcoming these effects is to handle the components as linked parts as long as possible. Linked parts are manufactured in...

The high amount of manual work in industrial assembly requires special measures in terms of progress monitoring and human-machine interaction to integrate these workstations into a digital production environment. A new concept for an assembly assistance system enables the incorporation of progress monitoring, gesture control and worker support by u...

Many enterprises that use expensive capital goods outsource the process of spare parts supply and stocking to a maintenance-, repair-, and overhaul provider (MRO-provider). Because of the high value, these spare parts are stocked in repairable item systems, in which defective parts are repaired after removal from the machine and put back into stock...

Kurzfassung Die Herstellung kundenindividueller Produkte ist insbesondere für Anbieter komplexer Investitionsgüter ein zentraler Wettbewerbsfaktor. Aufgrund der hohen Anzahl an Kundenspezifikationen und der resultierenden Kombinationsmöglichkeiten ist eine Automatisierung von Montagebereichen in diesen Unternehmen nicht möglich. Montagetätigkeiten...

For safe and reliable machine operation, maintenance, repair and overhaul (MRO) activities are required. Spare parts demand forecasting and inventory planning, which is an important part of MRO activities, must be accurate to avoid costs because of surplus spare parts or machine downtimes. The restriction of reduced accessibility to wind turbines d...

In machines a broad range of operational and failure information, like hours of operation, temperatures of components or information about surrounding conditions are available. However, this information is barely used for failure prediction or maintenance planning. At the same time, product life cycles shorten and machine variants increase, making...

Production of complex and large-dimensioned goods in small lot sizes is a demanding task. In order to react to varying customer demand and changing product specifications assembly tasks are executed manually by skilled workers that provide an adequate level of flexibility. Although the task of controlling these assembly processes gets more complex,...

Die mechanische Bearbeitung von Mikrokugeln stellt besondere Anforderungen an die Spanntechnik. Wenn eine größere Stückzahl an Kugeln auf einem Werkstückträger zusammengefasst und auf diesem sowohl transportiert, bearbeitet als auch gemessen wird, sind das Einbetten in niedrigschmelzende Legierungen und das Aufkleben mit schnell härtenden Klebstoff...

Hochdurchsatzprüfungen kommen in der Pharma- und Lebensmittelindustrie sowie der Medizintechnik zur Anwendung und gestatten Analysen für eine große Anzahl von Proben. Zur logistischen Steuerung von Hochdurchsatzprüfungen mit mehreren Bearbeitungs- und Prüfstationen sind derzeit keine Methoden bekannt. Der Fachartikel stellt einen ersten Ansatz der...

In automated production processes grasping devices and methods play a crucial role in the handling of many parts, components and products. This keynote paper starts with a classification of grasping phases, describes how different principles are adopted at different scales in different applications and continues explaining different releasing strat...

Accurate estimates of renewal instances are necessary to avoid both machine breakdowns as well as unnecessary replacements. These instances are based upon a prognosis of the remaining useful lifetime of the components investigated but their usability is limited because of insufficient failure time data. Therefore the paper at hand deals with the in...

Expensive parts of machines do not have to be discarded when broken. Instead they can be repaired and put back into stock, forming a repairable item system. Lots of methods are known to determine stock levels, the number of backordered parts and waiting times in repairable item systems. Some of these methods consider limited repair capacity, but as...

A new wire joining process for wires with sub-millimeter diameters applying the rotary swaging was investigated. The basic idea is to join two wire ends by a tube segment. In the study different material combinations using steel (AISI304) and copper (CW004A) were examined. Further the realization of a form-locked joint was investigated. The formed...

This paper focuses on the integration of elementary force sensors into the fingers of parallel grippers. The theory of the approach of integrating three sensor elements into a gripper finger is described and the results of the practical evaluations are given. Strain gauges are used as elementary sensor elements. Two different design approaches are...

A rising challenge for the industry is an increasing demand for smaller components. Simple scaling of tools and parts to sub millimeter range is not always applicable. It is necessary to develop new manufacturing and handling processes for micro-machining. One possibility is to leave the components in a linkage during processing in order to enable...

Manufacturing and handling of micro parts is a great challenge due to their small dimensions. Manufacturing processes and the state of knowledge in macro technologies are not smoothly transferable to the micro world. This can be justified, for example, by size effects and the related, changed component behaviour. It is assumed that known statistica...

The feasibility of maintenance processes relies on the availability of spare parts. Spare part inventory planning is capital intensive. It is based on demand forecasting, which possesses a high potential in reducing inventories. Even if condition monitoring systems are installed in technical systems, condition monitoring information is barely used...

The use of offshore wind energy is supposed to play a significant role in future energy supply. Because offshore wind farms will be built in greater water depths and distances to shore according to other already realized offshore projects, maintenance is far more influenced by different restrictive factors. Limited availability of vessels, dependen...

The operational readiness of an aircraft fleet is based on a reliable maintenance, repair and overhaul (MRO). In order to reduce the downtimes of aircrafts, damaged components are replaced on site. The need for immediate replacements associated with long lead times require spare parts stocking. To operate on a competitive basis, the optimization of...

In the aviation industry, reliable spare parts supply is essential for continuous aircraft operation. Spare parts of high value are repaired and returned to stock after removal from the aircraft, forming a closed-loop supply chain. Current planning methods of maintenance, repair, -and overhaul providers (MRO providers) as well as research findings...

Kurzfassung Die Produktion kundenindividueller Produkte ist in vielen Branchen zu einem essentiellen Wettbewerbsfaktor geworden. Insbesondere in der Herstellung von Produkten, welche durch die kundenspezifische Fertigung der einzelnen Komponenten auf die Bedürfnisse des Kunden optimal angepasst sind, erfordert dies eine hohe Flexibilität der an der...

There is a broad variety of ecological audits, which can be considered in production or disposal processes. None of them have been adapted to inventory planning. In this paper an approach of combining sustainability aspects with spare parts ordering will be presented. It is investigated how costs for CO2 emission must change or have to be changed b...

The production of large-dimensioned, customer specific goods like machinery, investment goods, and special vehicles is a demanding challenge because of the integration of numerous customer specific features and the need for short delivery times. In addition, complex assembly operations require highly skilled workers to ensure the flexibility of pro...

Inventory control for spare parts is an element of life cycle management for machines. For reliable spare part supply and low costs for part procurement and recycling, spares are provided by closed-loop supply chains. After removal from the machine broken parts are repaired and put back into stock. Estimations of demand level, repair time and reple...

A central challenge of micro forming production is handling of piece parts, because scaling effects in the micro and macro range are different. Hence, a transformation of technology from macro to micro scale is complicated. One solution for overcoming these difficulties is to manufacture the components as linked parts. Linked parts are manufactured...

Force measurement systems help to increase the functionality and flexibility of gripper systems. The approach presented in this paper, demonstrates how a force measurement system can be integrated in the structure of a gripper finger so that the mass increase is kept to a minimum. The performances of two different finger designs are compared. Furth...

An approach for overcoming negative influences of scaling effects in micro production is the manufacturing of micro parts in a linkage. Due to the linkage a process reliable handling is enabled and chaining of the single process steps for manufacturing becomes easier. The consideration of the technological view in development projects is often insu...

Kurzfassung Forschungsvorhaben finden oft über lange Zeiträume und in interdisziplinären Teams unterschiedlicher Institutionen statt. Die Projekte benötigen eine strukturierte Möglichkeit zur Erfassung und Weitergabe des dezentral generierten Wissens. Dieser Beitrag beschreibt Anforderungen an das Wissensmanagement in interdisziplinären Forschungsv...

Today, research is often conducted for long durations in interdisciplinary teams, consisting of members from different institutes and areas of expertise. Thereby, structured mechanics to manage the generated knowledge constitute a crucial factor of success. This article presents requirements for such a knowledge-management system, based on a case s...

Based on the CO2 emissions of 1990, European countries are supposed to reduce their emissions. Therefore the European Union agreed on an emissions trading system. From the year 2012 on, the trading system will be introduced for the aviation industry. Subject are airlines, but suppliers like maintenance, repair and overhaul (MRO) providers are affec...