Robust Integrated Assembly Design and Conformance Methods for Direct Digital Manufacturing

该研究计划的主要长期目标是开发新的方法和工具，用于模拟、预测和验证直接数字制造(DDM)过程中功能组件的机械、功能和几何质量规范，重点是熔融沉积建模和选择性激光烧结/熔化过程。与减法制造工艺不同，DDM工艺在原料、工艺、零件几何形状和机械性能参数(变形、残余应力)之间具有复杂的、非线性的、高度耦合的、时间相关的行为。他们还受到与质量、集成公差的能力以及验证和演示相关的问题的困扰。目前，在用于模拟和预测多组件功能组件的几何和机械行为、可靠性和重复性(材料特性、尺寸精度)的模型方面存在知识缺口。具备这一能力将开启添加剂制造(AM)在制造全功能组件方面的潜在未来应用，这将对缩短机械产品的设计和制造周期的时间和成本产生巨大影响。 机械组件是机器的关键部件，在所有需要能量/材料转换的技术系统中都是必需的。几何精度和公差精度以及可预测的机械行为是装配的最重要特征。尽管有潜力，但目前AM工艺的成熟度水平不允许直接打印真正整合的设计元素所需的精密功能组件。拟议的设备将允许基础理论和实验研究，以创建用于设计和优化关键工艺参数的准确模型，以及在直接设计到制造功能部件的尺寸、几何、运动学和机械性能行为方面具有一致构建质量的多材料/多组分几何模型。 预计该项目的高潮将导致开发新的模型，这些模型将显著提高添加剂制造工艺的工艺能力，同时减少返工和报废形式的浪费。它还将减少设计和制造所花费的时间，从而缩短周期时间。该过程的交付成果将允许设计和打印合并的功能组件。该项目还将培训一些在设计和制造领域的HQP，重点是具有生产精密组件的能力和知识的综合直接数字设计和制造。

The primary long term objective of the research program is to develop novel methods and tools for simulation, prediction, and validation of mechanical, functional and geometrical quality specifications of functional assemblies for direct digital manufacturing (DDM) processes with a focus on fused deposition modeling and Selective laser sintering/melting processes. Unlike subtractive manufacturing processes, DDM processes have complex, non-linear, highly coupled, time dependent behavior between the feedstock, process, part geometry, and the mechanical properties parameters (deformations, residual stresses). They also suffer from issues related to quality, capability to integrate tolerances, and validation and demonstration. Currently, there is a knowledge gap in the areas of models for simulating and predicting geometric and mechanical behavior, reliability and repeatability (material properties, dimensional accuracy) for multi-component functional assemblies. Having the capability would unlock potential future applications of additive manufacturing (AM) for manufacturing fully functional assemblies which would have an immense effect on reducing the time and cost of design and manufacturing cycle of a mechanical product. Mechanical assemblies are a critical component of machines and are required in all technological systems requiring energy/material transformations. Geometrical and tolerancing precision and predictable mechanical behavior are the most important characteristics of an assembly. Despite having the potential, the current level of maturity of AM processes do not allow direct printing of precision functional assemblies which is required for truly consolidated design elements. The proposed equipment will allow fundamental theoretical and experimental research to create accurate models for design and optimization of critical process parameters as well as multi material/multi component geometric models with a consistent build quality in terms of dimensional, geometric, kinematic, and mechanical property behavior of direct design to manufacturing of functional parts. The project culmination is expected to result into development of novel models that would significantly improve process capability of additive manufacturing process, while simultaneously reducing the waste in form of rework and rejection. It would also reduce the time spent in design and manufacturing leading to shorter cycle times. The deliverables from the process will allow design and printing of consolidated functional assemblies. The project would also train a number of HQP in the field of design and manufacturing with a focus on integrated direct digital design and manufacturing with capabilities and knowledge pf producing precision assemblies.