Topology Optimization for Additive Manufacturing as an Enabler for Light Weight Flight Hardware

Abstract

Three case studies utilizing topology optimization and Additive Manufacturing for the development of space flight hardware are described. The Additive Manufacturing (AM) modality that was used in this work is powder bed laser based fusion. The case studies correspond to the redesign and manufacture of two heritage parts for a Surrey Satellite Technology LTD (SSTL) Technology Demonstrator Space Mission that are currently functioning in orbit (case studies 1 and 2), and a system of five components for the SpaceIL’s lunar launch vehicle planned for launch in the near future (case study 3). In each case, the nominal or heritage part has undergone topology optimization, incorporating the AM manufacturing constraints that include: minimization of support structures, ability to remove unsintered powder, and minimization of heat transfer jumps that will cause artifact warpage. To this end the topology optimization exercise must be coupled to the Additive Manufacturing build direction, and steps are incorporated to integrate the AM constraints. After design verification by successfully passing a Finite Element Analysis routine, the components have been fabricated and the AM artifacts and in-process testing coupons have undergone verification and qualification testing in order to deliver structural components that are suitable for their respective missions.

Review: The Impact of Metal Additive Manufacturing on the Aerospace Industry

“…DFAM aspects such as residual stress, build orientation, and support structure need to be considered to ensure that high-performance and complex geometry parts can be achieved in a practical and cost-effective manner [158]. For example, a topologically optimized DFAM is aimed at developing self-supporting structures, or structures with as little support as possible, to reduce material waste and incurred costs, while devising efficient heat transfer pathways to mitigate residual stress build-ups that could lead to part warpage [158,159].…”

“…While research on TO-DFAM consolidation in metal AM fabrication of parts for the aerospace sector is still an ongoing research subject, there have indeed been some success stories. These include the successful redesign and manufacture of two actively functioning heritage parts of a technology demonstrator space mission in orbit that was commissioned by Surrey Satellite Technology Ltd., and that of five components for the lunar launch vehicle system of SpaceIL that will be launched very soon [159].…”

Post-Processing of Complex SLM Parts by Barrel Finishing

“…In particular, SLM permits producing fully dense parts in a direct way, thereby saving on raw material with respect to subtractive technologies [6]. It promotes the possibility of producing customized metal components in a cost-effective manner, allowing great flexibility in production; the design freedom allows improving the efficiency [7] and the functionality [8,9] of existing designs, as well as the possibility to incorporate more complex features without drastically increasing the costs. This aspect includes the possibility to create features not fabricable conventionally, such as internal structures, e.g., lattice structures [10] or channels [11].…”

Topology and Response Surface Optimization of a Bicycle Crank Arm with Multiple Load Cases

“…Topology optimization has also been used for improving spacecraft design for years. A study by Orme et al [14] utilize additive manufacturing and topology optimization to develop space flight hardware. The additive manufacturing constraints include the minimization of support structures and heat transfer jumps that can cause artifact warpage.…”