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Ankle foot orthoses (AFOs) are medical devices prescribed to support the foot and ankle of drop-foot patients. Passive-dynamic AFOs (PD-AFOs) are an effective solution for less severe cases. While off-the-shelf PD-AFOs are rather inexpensive, they provide poor anatomical fit and do not account for the required patient-specific biomechanical support. Three-dimensional (3D) scanning and manufacturing technologies allow manufacturing PD-AFOs customized for the patient’s anatomy and functional needs. This paper aimed to report the overall procedure for designing and manufacturing a novel, fiberglass-reinforced polyamide, custom PD-AFO. The feasibility of the proposed procedure was tested in a case study. The methodology can be divided into the following steps: (i) foot and leg scanning, (ii) 3D design, and (iii) additive manufacturing via selective laser sintering. A custom PD-AFO was designed and manufactured for a 67-year-old male drop-foot patient following paraparesis in severe discarthrosis after spine stabilization surgery. AFO mechanical properties were measured via an ad hoc setup based on a servohydraulic testing machine. The functional outcome was assessed via gait analysis in three conditions: shod (no AFO), wearing an off-the-shelf PD-AFO, and wearing the patient-specific PD-AFO. As expected, wearing the PD-AFO resulted in increased ankle dorsiflexion in the swing phase with respect to the shod condition. Sagittal rotations of the hip, knee, and ankle joints were similar across PD-AFO conditions, but the custom PD-AFO resulted in faster walking speed with respect to the off-the-shelf (walking speed: 0.91 m/s versus 0.85 m/s). Additionally, the patient scored the custom PD-AFO as more comfortable (VAS score: 9.7 vs. 7.3). While the present analysis should be extended to a larger cohort of drop-foot patients, the novel PD-AFO seems to offer a valid, custom solution for drop-foot patients not satisfied with standard orthotics.

The Emergent Reefs project draws on the potential that emerges from a coherent utilization of the environment's inherent ecological structure for its own transformation and evolution, using an approach based on digitally simulated ecosystems and sparked by the possibilities and potential of large-scale 3D printing technology. Considering tourism as an inevitable vector of environmental change, the project aims to direct its potential and economic resources toward a positive transformation, providing a material substrate for the human-marine ecosystem integration with the realization of spaces for an underwater sculpture exhibition. Such structures will also provide a pattern of cavities which, expanding the gradient of microenvironmental conditions, break the existing homogeneity in favor of systemic heterogeneity, providing the spatial and material preconditions for the repopulation of marine biodiversity.Starting from a digital simulation of a synthetic local ecosystem, a generative technique based on multi-agent systems and continuous cellular automata (put into practice from the theoretical premises in Alan Turing's paper "The Chemical Basis of Morphogenesis" through reaction-diffusion simulation) is implemented in a voxel field at several scales, giving the project a twofold quality: the implementation of reaction-diffusion generative strategy within a nonisotropic three-dimensional field, and integration with the large-scale 3D printing fabrication system patented by D-Shape®.Out of these assumptions, and with the intention of exploiting the expressive and tectonic potential of such technology, the project has been tackled exploring voxel-based generative strategies. Working with a discrete lattice eases the simulation of complex systems and processes across multiple scales (including nonlinear simulations such as computational fluid dynamics), starting from local interactions using, for instance, algorithms based on cellular automata, which then can be translated directly to the physical production system. The purpose of Emergent Reefs is to establish, through strategies based on computational design tools and machine-based fabrication, seamless relationships between three different aspects of the architectural process: generation, simulation, and construction, which in the case of the used technology can be specified as guided growth.

Polyhedral structures are a fascinating and efficient case of structural virtuosity. However, their adoption to date has been limited because of geometrical, structural and fabrication complexities. This paper introduces a modelling pipeline to provide a rigorous -yet practical-approach to the challenges linked to the realisation of 3D polyhedral structures, from early-stage design to fabrication. A custom-developed modelling add-on is utilised for reconstructing the underlying topology of 3D polyhedral structures and implementing a component-based approach for the design development. Concurrently, an innovative digital fabrication strategy based on Additive Formwork Manufacturing is presented, with a detailed description of the process and illustration of a fully-functional physical prototype. Methodological and software developments are applied to the fabrication experiments where the approach is tested with in-depth design and construction insights. The approach is ultimately discussed for the development of real-world structures and in light of the potential adoption by non-expert computational designers.

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