# Development Workflow for Manifolds and Fluid Components Based on Laser Powder Bed Fusion
## 2 Methodology Development  
As previously identified, [PERSON] [5] offers a comprehensive process model for the universal development of AM parts. To guide the designer to a design that respects technological as well as economic aspects, this process constitutes the general structure of the proposed methodology. This structure is, however, supplemented with manifold-specific design phases and tasks. Additionally, suitable tools for the specific tasks are proposed. In that way, the methodology facilitates a complete exploration of the potentials enabled through advanced design while acknowledging the economic efficiency and reliable manufacturability of the resulting part. As depicted in Figure 2, the proposed development methodology starts with the planning and conceptual phase. These phases, including their individual steps, are transferred analogously from the VDI 2221 [7]. Based on the high significance of a detailed description of requirements, an independent list of requirements for the part is to be created in the first task. This list should describe all boundary conditions concerning the part, available AM technologies, material availability, and loads. This is a mandatory process step, which is executed for re-design tasks as well as new development tasks. Even though the requirements shall be formulated detached from the manufacturing technology used, AM-specific potentials and resulting requirements, for example, lightweight design, can already be addressed [5]. In the second task, the functional structure of the part is to be arranged hierarchically into main and sub-functions (cf. Figure 2) [21]. The exploration of design freedom in new- as well as re-designs benefits significantly from function-based thinking, being detached from conventional manufacturing restrictions. In doing so, all surfaces which serve a specific engineering function shall be identified, and their individual boundary conditions, for example, freedom of position, is specified. This facilitates a subsequent, flux of force-oriented design. Based on this analysis, different conceptual solutions for the identified, functional structure are to be developed in the third task. To assist the designer in exploring unconventional solutions, tools like \"AM-potential checklists\", \"the analysis of existing studies\" or \"cross-departmental brainstorming\" can be utilized during this task. It is important to conduct such an extensive conceptual phase for re-designs as well. Existing solutions may include conventional thinking barriers, whereas the presented steps and tools create a large solution space for innovative concepts [5]. In the following task four, the concept assessment, the acquired concepts are evaluated by \"pairwise comparison\" and \"value benefit analysis\", which are specified/recommended in VDI guideline [7]. The assessment criteria for the value benefit analysis need to be adapted to consider the new AM aspects [5]. The following criteria are proposed for the assessment of manifold concepts:  
* Potential for size reduction
* Potential for weight reduction
* Potential for improved hydraulic efficiency
* Technical feasibility/ development risk
* Degree of innovation
* AM material efficiency
* Profitability of the build job  
Based on the quantitative assessment, one concept is selected for the embodied design phase. In this phase, potentials for improved product performance can be realized through advanced design. The chosen concept is introduced to the decision knot, in which tasks five to seven are executed iteratively. First, the parts main elements are designed and positioned according to the specified boundary conditions [5]. For manifold bodies, these are primarily installation spaces, hydraulic connectors, fixation points for the motor, and  
Figure 2: Development methodology for Additive Manufacturing (AM) manifolds. Squared boxes: process-tasks; round boxes: process-outputs; diamond-shaped boxes: assessment-tasks. pump.