In sandwich structures, mass can be reduced or mechanical properties increased if the challenging local load distribution can be improved. Through numerical optimizations, novel designs can be determined and investigated in physical and virtual tests. This paper presents an approach for load path-optimized design of sandwich structures and novel design concepts. The approach is applied to the design concept of honeycombs filled with potting compound. Due to the shown transferability to higher structural levels, it can be used as a basis for the design optimization of any sandwich structure.

Adaptive structures have the potential to play a significant role in saving resources in the construction industry in the future. For realisation, this requires actuators that meet the requirements of different buildings with their specific load-bearing structures. In the past, the actuators were mainly developed particularly for one exemplary load-bearing structure. This paper analyses the primary classifications for buildings, followed by challenges of adaptive structures, before outlining the draft of a framework for actuators for adaptive structures to speed up and simplify development.

This paper presents a method for the lightweight design of robotic links subject to dynamic loads and requirements on the overall system stiffness. It includes (1) a decomposition scheme to enable separate component optimization and (2) an approach based on topology optimization for optimal load path design of screw connections. The approach reduces computing cost and mass of designs with screw connections.

Hybrid manufacturing enables to overcome additive manufacturing (AM) constraints regarding the maximum feasible part dimension and/or complexity through part separation and subsequent adhesive joining of AM sub-parts. To ensure structural integrity of the joint at a minimum use of substrate volume, the AM inherent freedom of design can be exploited by realizing 3D micro scarf adhesive joints. The performance of this novel adhesive joint design was assessed by conducting optical measurements and static tensile tests using samples fabricated by laser-based powder bed fusion of metals (PBF-LB/M).

With increasing life expectancy, the risk of diseases of the central nervous system, such as cancer, strokes, etc., also increases. Strokes often result in injury to the sciatic nerve, which is responsible for controlling the calf muscles (plantar and dorsal flexors). A so-called ankle joint orthosis (AFO) helps to support the pathological gait and to avoid foot drop during gait. Passive orthoses are of particular importance for research, as they do not require additional incoming energy from outside to the orthotic system. However, current passive orthoses are often not personalized. On the one hand, because they usually have only a temporary muscle-building function and, on the other hand, because the individual design process is computationally time consuming and thus expensive. This paper presents a possibility to pre-dimension and pre-design passive orthoses fast and cost-efficiently by reducing the complexity of the model based on volume-optimized truss elements. Therefor a traditional high calculation intensive design procedure is compared with the complexity reduced model to show its effectiviness and the similarity of the results.

Tuned mass dampers may be used to improve vibrational behavior of structures. However, they require space to move. This paper presents an approach to incorporate tuned mass dampers into a lightweight-optimized structure without extra space requirement. It is based on (1) topology optimization (TopOpt) with unit cells and (2) vibration reduction with multiple tuned mass dampers (m-TMD) within the unit cells. The topology optimization is performed with a physics-informed penalty factor, unique to the chosen unit cell. Subsequently, the weight optimal density distribution is realized by populating the design domain with unit cells of ten different densities. To reduce the induced vibration, m-TMDs are placed inside the cavities of the unit cells in the grey scale regions. The effectiveness of the approach is demonstrated for the design of a 2-segment robot arm. The resulting unit cell robotic arm (UC-Arm) is 3.6% lighter than the reference model, maintains the same static performance, and shows a 60% smaller dynamic displacement in the observed frequency range. No extra space is required for the motion of the m-TMD.

Aluminum foam sandwich (AFS) is an innovative material for lightweight structures, consisting of an aluminum foam core surrounded by two face sheets of aluminum. The advantages of AFS are a low density combined with a high bending stiffness, good energy absorption properties, and high recyclability, meaning it can be used for many different applications. However, the number of realized series applications with AFS is low caused by a lack of design knowledge, as shown in various studies. In order to address this lack of design knowledge, a design guideline is to be developed. This paper focuses on the development of such a design guideline based on requirements and demands from the industry and presents a structure. In addition, the individual contents of the design guideline are explained in more detail in order to clarify how designers can be supported in the future when designing products with AFS, so that the full potential of this material can be realized. Finally, a survey in an industrial context evaluates the extent to which this design guideline is a useful form of support, in order to check whether its application can improve the design process with AFS.

Drive units of eBikes are used in every type of bicycle and for different riding scenarios and riders. Due to the different riders and bike types, an enormous variety of influencing parameters and load spectra must be considered during the design process. Therefore, in this paper, a systematic approach for the optimization of the drive unit is presented, which adopts and combines several approaches from design theory. The focus is on efficient modeling and simulation of the relevant parameters and load spectra to minimize uncertainties in the design process.

Based on a system analysis, dimension-reduced parameter spaces are formed for the simulation of the system, meta-models are integrated into the simulation model and the results of the simulation are transferred into a data-based surrogate model to cover the parameter space in an efficient way with a minimum number of time consuming FE simulations. Furthermore, a coordinate-based evaluation method is presented for the FE model in order to form the input for the surrogate model, reduces the amount of data, and to allows a geometry- and mesh-independent evaluation to compare different models.

Topology Optimization (TO) is an established method for the development of high strength and lightweight structural components. However, its results have to be geometrically revised to obtain a computational model that meets product development requirements. Design has to be in accordance with manufacturing constraints. Geometry reconstruction therefore still is a typically manual and tedious task, but increasingly supported by computational and automated approaches. In this paper, the inclusion of a casting constraint in an automated Medial Axis based reconstruction method is presented. Since the Medial Axis provides cross-section values by the computation of maximally inscribed spheres, this information is used for geometry reconstruction and even further for the purposeful adaption of the cross-section to match Heuver's circle method. Thereby, the directed solidification of molten material is considered. With a predefined feeder position, the demonstrator of a suspension control arm is used to show the application of the method. Resulting CAD-models are also structurally evaluated for their stiffness characteristics.

The potentials of additive manufacturing for objectives such as lightweight construction are not yet fully exploited. In this paper, the possibilities of integrative function and system modelling for this challenge will be discussed. In a design study, a triathlon trailer is designed considering the constraints of AM. A suitable system boundary is to be detected using the one-part device method. The findings of the study will help to understand in which form methods such as functional modelling can be applied or adapted for the application of additive manufacturing.

Aluminum foam sandwich (AFS) is an innovative material for lightweight structures due to its various advantages (e.g. low specific mass). Today, many material properties (e.g. strength) are still not well researched, which is why AFS is not yet considered in current material selection processes. Therefore, AFS has rarely been used in the past and its application potential remains unused. This paper presents an approach toward an appropriate method for considering AFS in material selection processes to assist designers in evaluating whether the use of AFS in an application is profitable.

By means of additive manufacturing, especially laser powder bed fusion, particle dampers can be integrated locally into structural components and thus significantly reduce component vibrations. However, detailed design recommendations for additively manufactured particle dampers do not yet exist. The research question in this paper is: How can the effect of particle damping be described as a function of excitation force, cavity width and cavity length? For beams made of AlSi10Mg, it is shown that a powder-filled cavity of 2.5% to 5% is sufficient to increase the damping by more than x10.

Biological solutions are often used for developing technically innovative products in a biomimetic process. However, biological solutions do not always make it into a successful technical product, e.g. due to a lack of knowledge on the mechanisms of action. A new approach is presented for transferring biological solutions based on complex mechanisms of action. It is based on mathematical optimization methods and applied to the lightweight design of the musculoskeletal system. Finally, first technical implementations in the field of robotics, among others, will be presented.

Truss structures are a stiff, economical, and efficient lightweight design, the limiting factor of these structures are usually the load transfer elements. This paper presents an analytical design method for optimized adhesive tubular lap joints between CFRP tubes and aluminium inserts. The analytically optimized design agrees very well with the numerical simulations and experimental results. Although the experiments show a highly non-linear behaviour, where a linear elastic correlation is expected, the total load capacity is only reached when the adhesive is fully plasticised.

Aircraft cabin monuments must be optimized in terms of lightweight design, cost structure and variance. Model-based approaches support the aircraft data and help to modify them consistently during further development. In this paper, a holistic methodological approach for product families of aircraft cabin development is shown, which integrates lightweight and cost-efficient aspects, in addition to the variance focus. For this purpose, the development of cost-efficient and ligthweight optimized cabin modules is supported in a model-based way.

Lightweight design in interconnected systems becomes more and more complex as the interdependencies cannot be overseen by the product developer. Varying one component might not only influence the interfaces to other components but also the underlying production systems.

Therefore, this contribution focuses on the product/production interdependencies and how they can be supported within lightweight design. Based on a functional description of the product it is possible to derive new lightweight design solutions and also to evaluate the change propagation in the production system. For this, a method for the impact and risk analysis is integrated in the lightweight design method Extended Target Weighing Approach (ETWA). By doing so, a risk value for the adapted production system can be calculated and different design concepts can be compared.

The application of the developed method on a simplified use-case shows great potentials when evaluating the impact of a newly developed lightweight design solution on an already existing production system supporting the product development in decision making.

Aluminum foam sandwich (AFS) is an innovative material combination for designing lighter products and has many advantages such as a high bending stiffness at a low density and good energy absorption properties. Although the material is ready for series production, the number of industrial applications is low because of the high costs of the material, a lack of design knowledge and missing reference applications. This paper focuses on the aspect of missing reference applications and how to improve this situation in order to give designers an idea of where the material could be used profitably and to provide the basis for a selection method. Therefore, a systematic literature review is carried out to identify profitable applications with their respective advantages. As a main result, a set of motivators for the use of aluminum foam sandwich is developed, which will support the designer in evaluating the potential use of aluminum foam sandwich.

As a result of the increasing challenges in the field of lightweight constructions, the demand for efficient joining technologies is continuously rising. For this purpose, cold forming processes offer an environmental friendly and fast alternative to established joining methods (e.g. welding). However, to ensure a high reliability, not only the selection of an appropriate procedure, but also the dimensioning of the individual joint is essential. While product designers can rely on a wide range of design principles for thermal processes, the dimensioning and evaluation of mechanical joining processes is mainly based on expert knowledge and a few experimental tests. Although few studies already investigated the numerical analysis of mechanical joints, an approach for the sustainable and consistent optimization of the strength and reliability of joining connections for varying use-cases is not available yet. Motivated by this lack, this paper presents an approach for the automated transfer of information within the process chain and the data-based analysis of mechanical joints by using clinching as an example. Therefore, the CRISP-DM reference model is used for the systematic data mining.

The approach of functional integration has the potential to solve challenges regarding lightweight design and resource efficiency since the number of parts and therefore the weight and needed installation space can be reduced. One important step in developing integrative concepts is the pre-selection of suitable functions or components. Previous methods of pre-selection take various aspects into account. However, pre-selection based on these methods usually requires additional tables and forms, whose preparation and editing quickly becomes time-consuming. At the same time, most of the development engineers are working on CAD models. However, their use in the selection of suitable integration partners is not yet supported sufficiently. The development of more than 80 concepts on five different vehicles has shown that the consideration of geometric properties (position, orientation, size) is effective, as they can be identified with minimal analysis effort while working on CAD. In this paper a four-step procedure is presented how integration partners can be identified directly on the basis of CAD models. A following evaluation with development engineers in practice completes the research.

Polygon meshes and particularly triangulated meshes can be used to describe the shape of different types of geometry such as bicycles, bridges, or runways. In engineering, such polygon meshes can occur as finite element meshes, resulting from topology optimization or laser scanning. This article presents an automated parameterization of polygon meshes into a parametric representation using subdivision surfaces, especially in topology optimization. Therefore, we perform surface skeletonization on a volumetric grid supported by the Euclidian distance transformation and topology preserving and shape-preserving criterion. Based on that surface skeleton, an automated conversation into a Subdivision Surface Control grid is established. The final mid-surface-like parametrization is quite flexible and can be changed by variating the control gird or the local thickness.