Page 37 - ESAM-1-1
P. 37

Engineering Science in
            Additive Manufacturing                                                   Gen-AI for lattice structure design



            high-performance applications ranging from aerospace   design strategy available. Conventional approaches such as
            components to biomedical implants. 4,8,9  AM’s freedom of   topology optimization, parametric modeling, and physics-
            design has pushed lattice design to a new level, allowing   based simulations have long been employed to generate
            engineers to lightweight parts (minimize material and   and refine lattice geometries. 31,32  These methods, while
            weight) when maintaining or even improving mechanical   effective, often require significant computational resources
            performance. 10-12  Such lattices provide high surface area   and manual intervention to achieve optimal results. What
            and tunable stiffness for improved biological integration.   distinguishes Gen-AI from traditional computational
            The materials used for AM-built lattice structures   design methods is its scalability, adaptability, and capability
            encompass both metallic and polymer-based materials. 13,14    to uncover non-intuitive solutions within vast design
            Metallic lattices, often fabricated from materials like   spaces. Traditional methods often rely on iterative manual
            titanium, stainless steel, or aluminum alloys, are widely   adjustments or rule-based algorithms, which can be time-
            used in aerospace, biomedical implants, and automotive   consuming and limited in scope. In contrast, Gen-AI
            components due to their high strength, durability, and   rapidly evaluates numerous design permutations, identifies
            thermal resistance. 15-19  On the other hand, polymer-based   optimal solutions, and adapts to complex, multiobjective
            lattices,  crafted from materials such as nylon, polylactic   constraints. This ability accelerates the design process and
            acid (PLA), or thermoplastic polyurethane (TPU), are   fosters innovation by unveiling lattice configurations that
            advantageous for applications requiring lightweight,   may not be immediately apparent through conventional
                                            20
            flexible, or biocompatible structures.  The choice of   approaches. In essence, AM offers the capability to fabricate
            material significantly influences the design strategy,   highly complex lattice structures, while Gen-AI serves as
            performance outcomes, and process considerations in   the intelligent engine that designs these structures for peak
            lattice fabrication. Therefore, understanding material-  performance. The synergy between AM and Gen-AI not
            specific design requirements is essential for optimizing the   only streamlines the design-to-production workflow but
            performance and manufacturability of lattice structures in   also pushes the boundaries of what is achievable in lattice
            diverse application scenarios.                     architecture. 33,34
              In recent years, Gen-AI has emerged as a transformative   Figure  2 presents a typical example of lattice
            approach in automating and enhancing lattice design for   structure generation using Gen-AI, demonstrating
            AM. 23-25  Gen-AI in design, often referred to as generative   the transformation from initial Gaussian noise to final
            design in engineering contexts, utilizes sophisticated   implicit and mesh representations suitable for AM.
                                                                                                            35
            machine learning algorithms to autonomously explore an   Lattice structures have emerged as a transformative design
            extensive array of design possibilities that satisfy predefined   strategy in various industries due to their unique ability to
            performance objectives. 26,27  Unlike conventional machine   balance lightweight characteristics with high mechanical
            learning models that primarily focus on prediction or   performance. However, optimizing lattice architectures
            classification  tasks,  Gen-AI  models  actively  generate   for specific functionalities, such as energy absorption,
            new data instances, enabling the creation of novel and   biomedical customization, mechanical strength, and
            optimized design solutions. 28,29                  thermal management, remains a complex challenge. 36,37

              Common Gen-AI techniques applicable to lattice     In  applications  requiring  energy  absorption  and
            design include generative adversarial networks (GANs),   impact resistance, Gen-AI can optimize lattice parameters
            variational autoencoders (VAEs), and diffusion models,   like cell size, shape, and wall thickness to achieve
            as illustrated in Figure 1. Each of these models operates   controlled deformation under impact, enhancing safety in
            on distinct mechanisms: GANs employ a competitive   automotive, aerospace, and protective gear applications. 38,39
            framework between a generator and a discriminator to   In the medical field, customized lattice orthoses and
            create  realistic designs;  VAEs encode  input data  into  a   implants benefit from generative design, where Gen-AI-
            latent space and decode it to generate variations; and   driven models, combined with patient-specific 3D scans,
            diffusion models progressively refine random noise into   enabled the fabrication of ergonomic, lightweight orthoses
            structured  designs.  These  models  empower  engineers   via AM. 40,41  For lightweight strength and mechanical
            to set specific design goals, such as maximizing stiffness   optimization, Gen-AI excels in creating lattice structures
            when minimizing weight, and allow the algorithms to   that minimize weight without compromising strength,
            autonomously propose optimal lattice geometries. 30  which is especially valuable in aerospace and automotive
              While Gen-AI has emerged as a transformative approach   sectors. 42,43  Finally, in heat dissipation and thermal
            to lattice structure design, it is not the only computational   management, Gen-AI facilitates the design of lattices




            Volume 1 Issue 1 (2025)                         2                          doi: 10.36922/ESAM025110006
   32   33   34   35   36   37   38   39   40   41   42