In order to enable even complex processes such as the joining of additively manufactured components by laser in production in a quality-assured way, the existence of specialist knowledge in companies is absolutely essential. To bundle this knowledge for process control and monitoring independently of personnel, an expert system is being developed in the IGF research project of FQS - Forschungsgemeinschaft Qualität e.V. entitled "Quality assurance in laser beam welding of additively manufactured thermoplastic components (QualLa)". By integrating specialist knowledge into the expert system, this knowledge can be secured in companies in the long term and processes can continuously be carried out with high qualitative standards.
additive manufacturing, 3D printing, FDM, laser transmission welding, laser beam welding
Qualitative uncertainties are a key challenge for the further industrialization of additive manufacturing. To solve this challenge, methods for measuring the process states and properties of parts during additive manufacturing are essential. The subject of this review is in-situ process monitoring for material extrusion additive manufacturing. The objectives are, first, to quantify the research activity on this topic, second, to analyze the utilized technologies, and finally, to identify research gaps. Various databases were systematically searched for relevant publications and a total of 221 publications were analyzed in detail. The study demonstrated that the research activity in this field has been gaining importance. Numerous sensor technologies and analysis algorithms have been identified. Nonetheless, research gaps exist in topics such as optimized monitoring systems for industrial material extrusion facilities, inspection capabilities for additional quality characteristics, and standardization aspects. This literature review is the first to address process monitoring for material extrusion using a systematic and comprehensive approach.
Material extrusion, Fused deposition modeling, Process monitoring, Sensor technology, Research gaps
The machine learning based method for layout optimization of smallscale modular conveyor systems, which is developed within a research project at IPH – Institut für Integrierte Produktion Hannover gGmbH, provides SMEs a decision support, which enables them to execute complex layout planning independently. In addition, the machine learning method is intended to reduce the cost and time required for planning and to improve the quality of the solution compared to manual layout design.
Small-scale modular conveyors, conveyor systems, machine learning, artificial intelligence
Factory planning is an important tool for
manufacturing companies to raise their efficiency and to
maintain their competitiveness by changing market or
customer requirements. A special challenge is the acquisition
of layout data and the processing of this data in suitable
planning tools. Current approaches still measure manually
or have to transfer acquired data from laser scanners by
hand into planning tools, which leads to a high effort and
error proneness.
This paper presents a holistic concept for automated
and systematic data acquisition and processing for factory
planning processes.
3D factory planning, automated drone flight, point cloud processing, 3D layout scan
In this article, a method for automatic visual obstruction detection and masktype congruent visual obstruction compensation, based on the principal of augmented reality, is presented. The method is based on the superposition of a simulated operator’s field of view with information from a scene reconstructed by two RGB-Cameras. These cameras are arranged in a way that they can record the scene information be-hind the view restriction. Besides the presentation of the test rig, a detailed presentation of the image pro-cessing software is given. With a view to the later use of the system in a forklift truck, the real-time capa-bility of the system will be tested and optimization possibilities will be discussed.
augmented reality, driver assistance system, forklift trucks, image processing, obstacle detection
The service life of rolling contacts is dependent on many factors. The choice of materials in particular has a major influence on when, for example, a ball bearing mayfail.Within an exemplary process chain for the production of hybrid high-performance components through tailored forming, hybrid solid components made of at least two different steel alloys are investigated. The aim is to create parts that have improved properties compared to monolithic parts of the same geometry. In orderto achievethis, several materials are joined prior to a forming operation. In this work, hybrid shafts created by either plasma(PTA)orlaser metal deposition (LMD-W) welding are formed via cross-wedge rolling(CWR)to investigate the resulting thickness of the material deposited in the area of the bearing seat. Additionally,finite element analysis (FEA)simulations of the CWRprocessare compared with experimental CWR results to validate the coating thickness estimation done via simulation. This allows for more accurate predictionsofthe cladding materialgeometry after CWR,and the desired welding seam geometrycan be selected by calculating the cladding thicknessvia CWR simulation.
Cross-Wedge Rolling, Forming, hybrid, tailored forming
Processing technology to improve the manufacturing of thermoelectric generators (TEGs) is a growing field of research. In this paper, an adaptable and scalable process comprising spray-coating and laser structuring for fast and easy TEG manufacturing is presented. The developed process combines additive and subtractive processing technology towards an adaptable ceramic-based TEG, which is applicable at high temperatures and shows a high optimization potential. As a prototype, a TEG based on Ca3Co4O9 (CCO) and Ag on a ceramic substrate was prepared. Microstructural and thermoelectric characterization is shown, reaching up to 1.65 μW cm−2 at 673 K and a ΔT of 100 K. The high controllability of the developed process also enables adaptation for different kinds of thermoelectric materials.
thermoelectric, laser structuring
Upfront investment costs for the tooling of injection molds are the basis for deciding if a mold is tooled and hence if a part is viable for mass-production. If tooling costs are too high, a product may not viable for production. If tooling costs are estimated too low by the tool shop, contract implications may arise.
The goal of this research is to develop a method with humanlike quotation accuracy, achieve standardization, factor in historic quotation data and shorten quotation process times. The machine learning approach developed is based on geometry data of parts and additional meta-information.
injection molding, tooling, industry 4.0
Quality assurance methods are a central success factor for the further industrialization of additive manufacturing. This paper presents an approach for an optical inspection system that controls the quality of additive material extrusion layer by layer. The inspection task gets analyzed, hardware components for data acquisition are designed and a first step towards texture-analytical detection of defects is presented.
additive manufacturing, 3d printing, material extrusion, fused deposition modeling, image processing
The processing of ceramics is an important technology for various technical applications. In this paper, a highly
controllable process consisting of spray-coating and laser structuring to design ceramic layers on a versatile
applicable substrate is presented. A thermoelectric oxide, Ca3Co4O9, which is a type of thermoelectric material,
is used in the process and applied to a flexible ceramic substrate. The resulting structures have highly controllable
shapes and good thermoelectric properties, and they can be used to produce a printable thermoelectric
generator (TEG). The use of a flexible ceramic substrate and the high feasibility of the process lead to a universally
applicable procedure that can be used to process ceramics with unique structures and designs.
thermoelectric, printed electronic, laser structuring, printed ceramics, spray coating
The structured and future-orientated planning of factory layouts is an important factor in maintaining the competitive ability. However, conventional planning methods with 2D Layouts reach their limits because they can no longer map the increasingly complex factory structures in detail. Alternatives are offered by 360° environmental scanning methods, which currently only serve as a template for postmodeling. This article presents a method for planning directly in the factory image. The aim is to make the factory planning process more effective and less error-prone.
3D-factory layout, factory planning, production planning, point cloud, point cloud processing
This article shows how the abilities known to humans to be flexible and adapt to changing environmental conditions, which are reflected in human cognitive characteristics, can be transferred to industrial trucks in intralogistics. As examples for the implementation of Industry 4.0 in intralogistics, technologies are presented that enable industrial trucks to recognize their environment, communicate information, draw conclusions, act autonomously, make decisions, learn or plan. These capabilities will be realized by an optical positioning system for position determination, camera-based storage/retrieval support and sensor technology integrated into tires, as well as novel forms of interaction for industrial trucks in the form of speech and gestures.
automated guided vehicle, augmented reality, smart glasses
Driverless transport systems are a building block for more efficient production systems in intralogistics, but have weaknesses in human-machine interaction. In a complex research project, a voice-based assignment is being developed, among other things, which is intended to make human-machine interaction more intuitive and increase its acceptance.
automated guided vehicle, augmented reality, smart glasses, voice control
Belt conveyor systems are an excellent way of conveying bulk material. With increasing load and transport distance, these systems become larger and energy efficiency becomes an important factor. Rollers are an integral part of belt conveyor systems. The running behaviour of idlers during operation has an impact on the energy efficiency of the entire system. The development of driven idlers is seen as one way to reduce the energy consumption of belt conveyor systems. This contribution shows that the investigation of conventional and driven idlers under different conditions is necessary and that a test rig for the investigation of these idlers has been developed at the Institut für Integrierte Produktion Hannover.
idlers, rollers, driven idler, bulk material handling
The Collaborative Research Centre 1153 (CRC 1153) “Process chain for the production of hybrid high-performance components through tailored forming” aims to develop new process chains for the production of hybrid bulk components using joined semi-finished workpieces. The subproject B1 investigates the formability of hybrid parts using cross-wedge rolling. This study investigates the reduction of the coating thickness of coaxially arranged semi-finished hybrid parts through cross-wedge rolling. The investigated parts are made of two steels (1.0460 and 1.4718) via laser cladding with hot-wire. The rolling process is designed by finite element (FE)-simulations and later experimentally investigated. Research priorities include investigations of the difference in the coating thickness of the laser cladded 1.4718 before and after cross-wedge rolling depending on the wedge angle, cross-section reduction, and the forming speed. Also, the simulations and the experimental trials are compared to verify the possibility of predicting the thickness via finite element analysis (FEA). The main finding was the ability to describe the forming behavior of coaxially arranged hybrid parts at a cross-section reduction of 20% using FEA. For a cross-section reduction of 70% the results showed a larger deviation between simulation and experimental trials. The deviations were between 0.8% and 26.2%.
cross-wedge rolling, hybrid forming, FEA, coating thickness
Abstract: For factory planning projects the layout capturing and layout processing process need a huge amount of effort, because they are typically done by hand. These processes could be accelerated and optimized by using a drone and automated analysis algorithms. Furthermore, this article shows a way to raise the digitization level for industrial processes. The key aspect lies on the usage of a drone in indoor environment and the processing of three-dimensional point cloud models for factory planning processes.
drone, factory planning, 3D-factory layout, object recognition
In this paper, the validation of an inductive sensor for an energy self-sufficient sensor for condition monitoring of wet-running steel disc clutches in marine gearboxes is presented. For a reliable operation of these a permanent monitoring of their state is advisable. As part of condition-based maintenance, more and more sensors are being installed in machines. Reliability becomes even more important when people are endangered by possible failure of the machines. In shipping, it is essential that, for example, the powertrain and thus the transmission are in perfect condition. In case of long distance traveling, wear or even damage of important components has to be known so that maintenance can be carried out proactively. To address this need an energy self-sufficient and wireless sensor network is developed. Miniaturized sensor nodes monitor torque, rotational speeds, temperatures as well as the wear condition of the torque transmitting components. The energy needed to operate these sensors is obtained from the surrounding environment. Thus, the system operates wirelessly and without an external energy supply, whereby the installation and maintenance costs decrease significantly. In addition to the concept of sensor integration in the transmission, the energy harvesting concept is also described in more detail. Finally, measurements are taken in a gear-like environment and the behavior of a magnetoinductive sensor in a not constantly supplied situation has been examined.
ship, gearbox, wear, sensor, torque
This paper describes the development and prototypical implementation of an energy self-sufficient sensor for condition monitoring of wet-running steel disc clutches in marine gearboxes. For the precise control of an automated system and the monitoring of its performance, the knowledge about the possible wear is an essential prerequisite. In addition, the storage of sensor data over the life of the system offers the possibility of long-term condition monitoring. The combination with various other technological components creates a solution that enables cost-effective condition monitoring of marine gearboxes. Compared to existing systems, for example, the costs for installation and maintenance are significantly reduced. Both the methodology from the morphological box to the fine concept as well as the first measurements of the sensors are presented.
automated system, condition monitoring, metrology, clutch, gearbox
Structured factory planning is a key to ensure the competitiveness concerning to the increasing pressure from globalization and the high market dynamic. Companies though avoid to do factory planning projects, because of the high effort. For this reason, the processes of factory layout capture and factory layout assessment are in need of improvement in order to increase the efficiency, which will be achieved through new technologies and a semi automation of the processes.
factory planning, drone, photgrammetry, laserscan, image data processing
Black marking as micrometer scaled binary coding applied on shafts by ultrashort pulsed lasers with high contrast and without ablation as a non-contact sensor system for combined measurement of angular position and torque.
laser materials processing, sensors, absorption, image analysis
