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Rational positioning of 3D-printed voxels to realize high-fidelity multifunctional soft-hard interfaces

Cruz Saldivar, M. (author), Veeger, Robin Petrus Elias (author), Tay, E.T.W.S. (author), Fenu, M. (author), Klimopoulou, M. (author), van Osch, G.J.V.M. (author), Fratila-Apachitei, E.L. (author), Doubrovski, E.L. (author), Mirzaali, Mohammad J. (author), Zadpoor, A.A. (author)

Living organisms use functional gradients (FGs) to interface hard and soft materials (e.g., bone and tendon), a strategy with engineering potential. Past attempts involving hard (or soft) phase ratio variation have led to mechanical property inaccuracies because of microscale-material macroscale-property nonlinearity. This study examines 3D...

journal article 2023

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Xpandables: Single-filament Multi-property 3D Printing by Programmable Foaming

Ozdemir, Mehmet (author), Doubrovski, E.L. (author)

We propose a new approach to obtain local property variations in 3D-printed objects using a single-nozzle 3D printer and one filament. We use foaming filaments which expand at different rates due to different temperatures. We present an approach to harness this varying expansion by including parameters of the 3D printing process in the design...

conference paper 2023

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Feasibility of On-demand Additive Manufacturing of Spare Parts

van Oudheusden, A.A. (author), Buijserd, A.J. (author), Doubrovski, E.L. (author), Flipsen, Bas (author), Faludi, Jeremy (author), Balkenende, R. (author)

Spare parts availability is crucial for extending the life of consumer products. However, long-term availability could lead to high stocks of spare parts, which might not be used. Instead, on-demand manufacturing of spare parts with additive manufacturing (AM) is a promising alternative. This paper presents a method to evaluate parts on their...

conference paper 2023

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Photogrammetric Reconstruction of a Stolen Statue

Liu, Z. (author), Doubrovski, E.L. (author), Geraedts, Jo M.P. (author), Yam, Y (author), Wang, W. (author), Wang, C.C.L. (author)

In this paper, we propose a method to reconstruct a digital 3D model of a stolen/damaged statue using photogrammetric methods. This task is challenging because the number of available photos for a stolen statue is in general very limited – especially the side/back view photos. Besides using standard structure-from-motion and multi-view stereo...

conference paper 2023

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Cyano-Chromic Interface: Aligning Human-Microbe Temporalities Towards Noticing and Attending to Living Artefacts

Zhou, J. (author), Kim, Raphael (author), Doubrovski, E.L. (author), Soares de Oliveira Martins, J. (author), Giaccardi, Elisa (author), Karana, E. (author)

Microbes offer designers opportunities to endow artefacts with environmental sensing and adapting abilities, and unique expressions. However, microbe-embedded artefacts present a challenge of temporal dissonance, reflected by a “time lag” typically experienced by humans in noticing the gradual and minute shifts in microbial metabolism. This...

conference paper 2023

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Bioinspired rational design of bi-material 3D printed soft-hard interfaces

Cruz Saldivar, M. (author), Tay, E.T.W.S. (author), Isaakidou, A. (author), Moosabeiki, Vahid (author), Fratila-Apachitei, E.L. (author), Doubrovski, E.L. (author), Mirzaali, Mohammad J. (author), Zadpoor, A.A. (author)

Durable interfacing of hard and soft materials is a major design challenge caused by the ensuing stress concentrations. In nature, soft-hard interfaces exhibit remarkable mechanical performance, with failures rarely happening at the interface. Here, we mimic the strategies observed in nature to design efficient soft-hard interfaces. We base...

journal article 2023

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Advancing design for Additive Manufacturing Education: A focus on computational skills and competencies

Graziosi, Serena (author), Wu, J. (author), Doubrovski, E.L. (author), Meisel, Nicholas (author), Schütz, Martin (author), Stankovic, Tino (author)

The summer school is realized as a joint teaching project between several partner universities under the auspices of the IDEA League alliance. The school trains students and young researchers on exploring and applying the potential of computational-based strategies in design for additive manufacturing, while engaging in dedicated team working...

journal article 2023

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Nonlinear coarse-graining models for 3D printed multi-material biomimetic composites

Cruz Saldivar, M. (author), Doubrovski, E.L. (author), Mirzaali, Mohammad J. (author), Zadpoor, A.A. (author)

Bio-inspired composites are a great promise for mimicking the extraordinary and highly efficient properties of natural materials. Recent developments in voxel-by-voxel 3D printing have enabled extreme levels of control over the material deposition, yielding complex micro-architected materials. However, design complexity, very large degrees of...

journal article 2022

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Personalized product design through digital fabrication

Minnoye, A.L.M. (author), Tajdari, F. (author), Doubrovski, E.L. (author), Wu, J. (author), Kwa, F.S.S. (author), Elkhuizen, W.S. (author), Huysmans, T. (author), Song, Y. (author)

Personalized designs bring added value to the products and the users. Meanwhile, they also pose challenges to the product design process as each product differs. In this paper, with the focus on personalized fit, we present an overview as well as details of the personalized design process based on design practice. The general workflow of...

conference paper 2022

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Computational Design for Digitally Fabricated 3D Inductive Power Transfer Coils

Xu, J. (author), Doubrovski, E.L. (author), Geraedts, Jo M.P. (author), Song, Y. (author)

The geometric shapes and the relative position of coils influence the performance of a three-dimensional (3D) inductive power transfer system. In this paper, we propose a coil design method for specifying the positions and the 3D shapes of a pair of coils to transmit the desired power. Given region of interests (ROIs) for designing the...

journal article 2022

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Memory-Efficient Modeling and Slicing of Large-Scale Adaptive Lattice Structures

Liu, Shengjun (author), Liu, Tao (author), Zou, Qiang (author), Wang, W. (author), Doubrovski, E.L. (author), Wang, Charlie C.L. (author)

Lattice structures have been widely used in various applications of additive manufacturing due to its superior physical properties. If modeled by triangular meshes, a lattice structure with huge number of struts would consume massive memory. This hinders the use of lattice structures in large-scale applications (e.g., to design the interior...

journal article 2021

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Knitting 4D garments with elasticity controlled for body motion

Liu, Z. (author), Han, Xingjian (author), Zhang, Yuchen (author), Chen, Xiangjia (author), Lai, Y. (author), Doubrovski, E.L. (author), Whiting, Emily (author), Wang, C.C. (author)

In this paper, we present a new computational pipeline for designing and fabricating 4D garments as knitwear that considers comfort during body movement. This is achieved by careful control of elasticity distribution to reduce uncomfortable pressure and unwanted sliding caused by body motion. We exploit the ability to knit patterns in...

journal article 2021

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Bonding between silicones and thermoplastics using 3D printed mechanical interlocking

Rossing, Lars (author), Scharff, R.B.N. (author), Chömpff, Bryan (author), Wang, C.C. (author), Doubrovski, E.L. (author)

Silicones have desirable properties such as skin-safety, high temperature-resistance, and flexibility. Many applications require the presence of a hard body connected to the silicone. Traditionally, it has been difficult to create strong bonding between silicones and hard materials. In this study, a technique is presented to control the...

journal article 2020

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Multi‐material 3D printing of functionally graded hierarchical soft–hard composites

Mirzaali, Mohammad J. (author), Cruz Saldivar, M. (author), Herranz de la Nava, Alba (author), Gunashekar, Deepthishre (author), Nouri Goushki, M. (author), Doubrovski, E.L. (author), Zadpoor, A.A. (author)

Hard biological tissues (e.g., nacre and bone) have evolved for millions of years, enabling them to overcome the conflict between different mechanical properties. The key to their success lies in the combination of limited material ingredients (i.e., hard and soft constituents) and mechanistic ingredients (e.g., functional gradients and building...

journal article 2020

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Mechanics of bioinspired functionally graded soft-hard composites made by multi-material 3D printing

Mirzaali, Mohammad J. (author), Herranz de la Nava, A. (author), Gunashekar, D. (author), Nouri Goushki, M. (author), Veeger, R. P.E. (author), Grossman, Q. (author), Angeloni, L. (author), Ghatkesar, M.K. (author), Fratila-Apachitei, E.L. (author), Ruffoni, D. (author), Doubrovski, E.L. (author), Zadpoor, A.A. (author)

Functional gradients are material transitions that are found in nature and are known to result in materials with superior properties and multiple functionalities. The emerging multi-material 3D printing (=additive manufacturing, AM) techniques provide a powerful tool for the design and fabrication of bioinspired functionally graded materials ...

journal article 2020

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A Framework for Adaptive Width Control of Dense Contour-Parallel Toolpaths in Fused Deposition Modeling

Kuipers, T. (author), Doubrovski, E.L. (author), Wu, J. (author), Wang, C.C. (author)

3D printing techniques such as Fused Deposition Modeling (FDM) have enabled the fabrication of complex geometry quickly and cheaply. Objects are produced by filling (a portion of) the 2D polygons of consecutive layers with contour-parallel extrusion toolpaths. Uniform width toolpaths consisting of inward offsets from the outline polygons...

journal article 2020

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Reprintable paste-based materials for additive manufacturing in a circular economy

Sauerwein, M. (author), Zlopasa, J. (author), Doubrovski, E.L. (author), Bakker, C.A. (author), Balkenende, R. (author)

The circular economy requires high-value material recovery to enable multiple product lifecycles. This implies the need for additive manufacturing to focus on the development and use of low-impact materials that, after product use, can be reconstituted to their original properties in terms of printability and functionality. We therefore...

journal article 2020

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Color-Based Proprioception of Soft Actuators Interacting with Objects

Scharff, R.B.N. (author), Doornbusch, Rens M. (author), Doubrovski, E.L. (author), Wu, J. (author), Geraedts, Jo M.P. (author), Wang, C.C. (author)

Actuators using soft materials feature a large number of degrees of freedom. This tremendous flexibility allows a soft actuator to passively adapt its shape to the objects under interaction. In this paper, we propose a novel proprioception method for soft actuators during real-time interaction with previously unknown objects. First, we design...

journal article 2019

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Exploring the potential of additive manufacturing for product design in a circular economy

Sauerwein, M. (author), Doubrovski, E.L. (author), Balkenende, R. (author), Bakker, C.A. (author)

Additive manufacturing, also known as 3D printing, is acknowledged for its potential to support sustainable design. In this paper, we explore whether the opportunities that additive manufacturing offers for sustainable design are also useful when designing for a circular economy, and to what extent additive manufacturing can support design...

journal article 2019

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Fracture Behavior of Bio-Inspired Functionally Graded Soft–Hard Composites Made by Multi-Material 3D Printing: The Case of Colinear Cracks

Mirzaali, Mohammad J. (author), Herranz de la Nava, Alba (author), Gunashekar, Deepthishre (author), Nouri Goushki, M. (author), Doubrovski, E.L. (author), Zadpoor, A.A. (author)

The functional gradient is a concept often occurring in nature. This concept can be implemented in the design and fabrication of advanced materials with specific functionalities and properties. Functionally graded materials (FGMs) can effectively eliminate the interface problems in extremely hard–soft connections, and, thus, have numerous and...

journal article 2019