Soft Robotic Matter group @AMOLF

The Soft Robotic Matter group focusses on the design, fabrication and fundamental understanding of materials that are capable of autonomously adapting to – and even harnessing – variations in their environment. The group aims to uncover principles that help us understand how non-linearity and feedback can result in the emergence of complex – but useful – behavior in soft actuated systems. To this end, the Soft Robotic Matter group explores active and sensing elements to implement feedback capabilities and computation in soft architected materials, and uses a combination of computational, experimental and analytical tools. This line of research uniquely combines concepts from soft robotics and architected materials, providing new and exciting opportunities in the design of compliant structures and devices with highly non-linear behavior.

Principal Investigator

Johannes T.B. (Bas) Overvelde

About the PI
In May 2016, Overvelde became a tenure-track Group Leader @AMOLF, in Amsterdam, where he started his Soft Robotic Matter group. He is the third Group Leader within the Designer Matter initiative, a relatively new research line at AMOLF. 

Between 2004 and 2012, Overvelde studied applied physics and mechanical engineering at the Delft University of Technology, where he received both his BSc and MSc degrees in mechanical engineering cum laude. In April 2016, Overvelde finished his PhD in applied mathematics at Harvard University under the direction of professor Katia Bertoldi at the John A. Paulson School of Engineering and Applied Sciences. Overvelde’s PhD research focussed on harnessing compliance and instabilities in engineered structural materials and devices to achieve function. 

Job openings
We are currently recruiting talented students for a temporary intern positions in the Soft Robotic Matter group @ AMOLF. Interested? Apply online on the AMOLF-website.



Sabine Penning



Niels Commandeur



Dennis Kistemaker

PhD students


Agustin Iniguez-Rabago

PhD students

Giorgio Oliveri

Visiting students

Andor Bent

Bachelor student
@The Hague University of Applied Sciences

Mark ten Hooven

Bachelor student
@The Hague University of Applied Sciences

Aravind Jayasankar

PhD student
Max Planck Institute of Colloids and Interfaces

Yun Li

Bachelor student
Amsterdam University College


Origami-inspired Metamaterial

Recent years have seen an uprise of new materials with interesting and unusual properties that result from their regular periodic microstructure. Origami-based metamaterials based on the Miura fold pattern have gained a lot of attention for their ability to drastically change their shape and therewith creating a programmable metamaterial. In this line ofwork, we propose a completely new class of actuated 3D foldable materials with three degrees of freedom that can drastically change their shape, volume and stiffness by folding.
[Read more] [Last update 18 January 2017]

Tension Instability

A range of instabilities can occur in soft bodies that undergo large deformation. While most of them arise under compressive forces, it has previously been shown analytically that a tensile instability can occur in an elastic block subjected to equitriaxial tension. Guided by this result, using numerical simulations we designed an experimental setup, and conducted centimeter-scale experiments on thick elastomeric samples under generalized plane strain conditions and observed for the first time this elastic tensile instability.
[Read more] [Last update 21 September 2016]

Snap-through Soft Actuators

To increase the capabilities of mechanical devices, soft materials are emerging in the field of engineering. The stiffness of these soft materials makes them ideally suited for application in devices that deal with delicate and diverse tasks. To enable the necessary large deformation and actuation, these soft actuators and robots typically rely on large external input. In our research we aim to limit external input by exploiting snap-through instabilities in the design, therewith paving the way for fully autonomous soft robots.
[Read more[Last update 1 September 2015]

Functionally Graded Soft Robot

In this work, we describe the advantages of using advanced 3D printing techniques in the fabrication of soft robots that can jump using energy from combustion reactions. These techniques allow us to simplify the design and fabrication processes, but also enable the use of functionally graded material to solve problems related to interfacing rigid driving components to soft materials.
[Read more] [Last update 10 July 2015]

Tunable Photonic Crystal

In this work, we describe experimental and theoretical characterizations of both the photonic response and the mechanical properties of a dynamically tunable bio-inspired 3D gyroid photonic crystal structure that was fabricated using 3D printing methods at the centimeter scale. Our results show that this structure can be electromagnetically tuned by applying a deformation to the structure using mechanical loading.
[Read more] [Last update 7 October 2015]

Soft Sensors

Soft sensors comprising a flexible matrix with embedded circuit elements can undergo large deformations while maintaining adequate performance. These devices have attracted considerable interest for their ability to be integrated with the human body and have enabled the design of skin-like health monitoring devices, sensing suits, and soft active orthotics. We introduce a 3D finite element-based numerical tool to simultaneously characterize the mechanical and electrical response of fluid-embedded soft sensors of arbitrary shape, subjected to any loading.
[Read more] [Last update 20 December 2014]

Soft Medical Devices

A new class of devices is emerging that is constructed from soft materials instead of rigid materials. Soft actuators form a specific class of these devices and can be applied in for example the medical field as devices for rehabilitation or for predicting biomimetic motion of muscles. Besides fabrication and testing of these soft actuators, a large part of the research focuses on the use of Finite-Element Analysis to predict the non-linear response of the actuators, and therewith increasing the efficiency of the design process and the quality of the designs.
[Read more] [Last update 28 April 2015]

Metamaterial Design

The goal of this work is to design a new class of soft reconfigurable porous structures. By changing the pore shape of these structures we can not only tune the non-linear stiffness and Poisson’s ratio, but also the type of instability that occurs, i.e. microscopic or macroscopic instability. Both numerical and experimental work has been done to characterize these porous structures under uniaxial loading.
[Read more] [Last update 21 July 2015]

Topology Optimization

For my Master’s thesis at the Delft University of Technology I worked on a fluid-inspired topology optimization method called the ‘Moving Node Approach’ (MNA). In this method, we seek the optimal shape of a structure under applied boundary and loading conditions and specific constraints. In the MNA, the structure is represented by a fixed number of particles that can ‘flow’ through the design space, guiding the particles towards configurations that are more optimal.
[Read more] [Last update 2 April 2012]



(16) Overvelde, J. T. B., Mixe, M., Hoberman, C., Weaver, J., Bertoldi, K., (2017). ReBot: Untethered Reconfigurable Multi-gate Robotic System Constructed from Foldable Building Blocks. In preparation.

(15) Overvelde, J. T. B., Weaver, J., Hoberman, C., Bertoldi, K., (2017). Rational Design of Reconfigurable Prismatic Architected Materials. Nature, 541, 347-352. [De Volkskrant] [De Volkskrant online] [News & Views in Nature] [Harvard News] [pdf] 

(14) Wang, Z., Galloway, K., Overvelde, J. T. B., Polygerinos, P., Bertoldi, K., Walsh, C. J., (2016). Interaction Forces of Soft Fiber Reinforced Bending Actuators. IEEE/ASME Transactions on Mechatronics, 99. [pdf]

(13) Babaee, S., Overvelde, J. T. B., Chen, E. R., Tournat, V., Bertoldi, K., (2016). Reconfigurable Origami-inspired Acoustic Waveguides. Science Advances, 2(11), e1601019. [pdf]

(12) Overvelde, J. T. B., Dykstra, D. M. J., de Rooij, R., Weaver, J., Bertoldi, K., (2016). Tensile Instability in a Thick Elastic Body. Physical Review Letters, 117, 094301. [Harvard News] [pdf]

(11) Overvelde, J. T. B., de Jong, T. A., Shevchenko, Y., Becerra, S. A., Whitesides, G. M., Weaver, J., Hoberman, C., Bertoldi, K., (2016). A three-dimensional actuated origami-inspired transformable metamaterial with multiple degrees of freedom. Nature Communications. [NRC Handelsblad] [Financial Times] [Tech Insider] [Daily Mail] [The Telegraph] [Smithsonian] [ResearchGate featured article] [New Scientist] [Mic] [The Engineer] [TU Delta] [Harvard News] [pdf]

(10) Pouya, C., Overvelde, J. T. B., Kolle, M., Aizenberg, J., Bertoldi, K., Weaver, J. C., Vukusic, P., (2015). Characterization of a Mechanically Tunable Gyroid Photonic Crystal Inspired by the Butterfly Parides sesostris. Advanced Optical Materials. [pdf]

(9) Overvelde, J. T. B., Kloek, T., D’haen, J. J. A., Bertoldi, K., (2015) Amplifying the Response of Soft Actuators by Harnessing Snap-through Instabilities. Proceedings of the National Academic of Sciences of the United States of America. [Harvard News] [The Engineer] [TU Delta] [cover] [pdf]

(8) Coulais, C., Overvelde, J. T. B., Lubbers, L. A., Bertoldi, K., van Hecke, M., (2015). Discontinuous Buckling of Wide Beams and Metabeams. Physical Review Letters, 115, 044301[pdf]

(7) Bartlett, N. W., Tolley, M. T., Overvelde, J. T. B., Weaver, J., Mosadegh, B., Bertoldi, K., Whitesides, G. M., Wood, R. J., (2015) A 3D Printed, Functionally Graded Soft Robot Powered by Combustion. Science, 349, 161-165. [The Washington Post] [IEEE Spectrum] [Discovery] [Harvard News] [Popular Mechanics] [pdf]

(6) Polygerinos, P., Wang, Z., Overvelde, J. T. B., Galloway, K., Wood, R., Bertoldi, K., Walsh, C. J., (2014). Modeling of Soft Fiber-reinforced Bending Actuators. IEEE Transactions on Robotics, 31(3), 778-789. [pdf]

(5) Overvelde, J. T. B., Mengüç, Y., Polygerinos, P., Wang, Y., Wang, Z., Walsh, C. J., Wood, R. J., Bertoldi, K., (2014). Numerical Mechanical and Electrical Analysis of Soft Liquid-embedded Deformation Sensors. Extreme Mechanics Letters, 1, 42-46[pdf]

(4) Overvelde, J. T. B., Bertoldi, K., (2014). Relating Pore Shape to the Non-linear Response of Periodic Elastomeric Structures. Journal of the Mechanics and Physics of Solids, 64, 351-366. [pdf]

(3) Roche, E. T., Wohlfarth, R., Overvelde, J. T. B., Vasilyev, N. V., Pigula, F.A., Mooney, D. J., Bertoldi, K., Walsh, C.J., (2014). Bioinspired Soft Actuated Materials. Advanced Materials, 26(8), 1200-1206. [Research Highlight in Nature Materials] [News & Views in Nature Materials] [NRC Handelsblad] [Harvard News] [cover] [pdf]

(2) Overvelde, J. T. B., Shan, S., Bertoldi, K., (2012). Compaction Through Buckling in 2D Periodic, Soft and Porous Structures: Effect of Pore Shape. Advanced Materials, 24(17)2337-2342[pdf]

(1) Li, J., Shim, J., Deng, J., Overvelde, J. T. B., Zhu, X., Bertoldi, K., Yang, S., (2012). Switching Periodic Membranes via Pattern Transformation and Shape Memory Effect. Soft Matter, 8(40), 10322-10328. [pdf]

Documentaries and Exhibitions

“10 Degrees” (Sept 2016 – Jan 2017), exhibit at le Laboratoire, Cambridge US [web]

“The Origami Code” (2016), documentary by Francois-Xavier Vives, Dutch premiere INScience [web], aired NPO on 6 Nov. (min 32:49 – 35:01)

Selected Media Coverage

(33) Van Calmthout, Martijn. (2017) “Hogere knutselkunde.” De Volkskrant 11 March. [web] [web]

(32) Karhof, Joost. (2016) “Wetenschappers adopteren Origami.” Radio show NPO1 Nieuws en Co 4 November. [web]

(31) Vives, Francois-Xavier. (2016) “The Origami Code.” Documentary at Inscience Festival 2-6 November. [web]

(30) Aan de Brugh, Marcel. (2016) “Octopus als Robot.” NRC Handelsblad and NRC Next 3 September. [pdf] [pdf]

(29) Van Kasteren, Joost. (2016) “Dichte muur krijgt gaten met een keertje vouwen.” NRC Handelsblad 16 April. [pdf]

(28) Cookson, Clive. (2016) “Origami comes into the tech fold.” Financial Times  26 March. [pdf]

(27) Hansman, Heather. (2016) “A New Material Could Make Medical Devices That Expand and Collapse.” Smithsonian 18 March. [web]

(26) Joosten, Carla. (2016) “Zachte Robotica.” Elsevier 17 March. [pdf]

(25) Knapton, Sarah. (2016) “Bizarre shape-shifting material invented by Harvard.” The Telegraph 11 March. [web]

(24) Web editor (2016) “Researchers design versatile shapeshifting material.” ResearchGate 11 March. [web]

(23) Ceurstemont, Sandrine. (2016) “Shape-shifting matter could let houses crumple themselves away.” New Scientist 11 March. [web]

(22) Reader, Ruth. (2016) “Researchers Have Created a Shapeshifting Material Inspired by Origami.” Mic 11 March. [web]

(21) Web editor (2016) “Harvard team develops origami-inspired 3D structural material.” The Engineer 11 March. [web]

(20) Wassink, Jos. (2016) “Transforming materials.” DELTA 11 March. [web]

(19) Burrows, Leah. (2016) “Transforming materials.” Harvard News and Views 11 March. [web]

(18) Web editor (2015) “Delft Students Help Make More Dextrous Robots.” TU Delft Robotics Institute 27 August. [web] and other TU Delft web publications [EWI] [LR] [3ME]

(17) Edelman, Peter. (2015) “Niet-lineair gedrag handig gebruikt in kunstmatige spier.” Mechatronica & Machinebouw 21 August. [web]

(16) Wassink, Jos. (2015) “Ballooning muscles for robots.” DELTA 20 August. [web]

(15) Web editor (2015) “Soft actuator could remove need for robotic tethers.” The Engineer 18 August. [web]

(14) Burrows, Leah. (2015) “Controlling the uncontrollable.” Harvard News and Views 17 August. [web]

(13) Wright, Katherine. (2015) “Runaway buckling.” APS Physics 21 July. [web]

(12) Zegers, Gabby. (2015) “Metamaterial undermines 250-year-old construction principles” FOM 21 July. [web]

(11) Morad, Renee. (2015) “Jumping, Froglike Robot Takes a Big Leap Forward.” Robotics, Discovery 9 July. [web]

(10) Ackerman, Evan. (2015) “3D-Printed Explosive Jumping Robot Combines Firm and Squishy Parts.” IEEE Spectrum, 9 July. [web]

(9) Burrows, Leah. (2015) “Harvard Researchers Create Jumping Soft Robot Using 3-D Printer.” Harvard Gazette 9 July. [web]

(8) Feltman, Rachel. (2015) “This Jumping, Squishy Robot Looks Like a Tiny UFO.” Speaking of Science, The Washington Post 9 July. [web]

(7) Herkewitz, William. (2015) “Nearly Unbreakable Soft Robot Ignites Explosions to Jump.” New Technology, Popular Mechanics 9 July. [web]

(6) Ball, Philip. (2014) “Soft-hearted Robots.” News and Views, Nature Materials Vol. 13 April. [pdf]

(5) Martiradonna, Luigi. (2014) “Heart Twists.” Research Highlight, Nature Materials Vol. 13 January. [pdf]

(4) Aan de Brugh, Marcel. (2014) “Een nieuwe hartkamer van zachte kunststof.” NRC Handelsblad 28 February. [pdf]

(3) Kusek, Kristen. (2014), “Arti ficial muscles do the twist.” Wyss Institute 26 February. [web]

(2) Bosman, Annemieke. (2013) “Vliegende Hollander” Transfer Magazine, 4. [pdf]

(1) Elshof, Loes. (2009) “Excellence Program” Delft University of Technology[movie]

Invited Talks & Colloquia

(15) Soft Robotic Matter (2017) ICMS Complexity Science Winter School, Eindhoven (NL)

(14) Rational Design of Reconfigurable Prismatic Architected Materials (2017) 4D Printing & Meta Materials Conference, Sittard-Geleen (NL)

(13) Embracing Compliance and Instabilities to Achieve Function in Mechanical Metamaterials and Devices (2016) Soft Matter Meeting, Wageningen (NL)

(12) Soft Robotic Matter (2016) AMOLF Friday Seminar, Amsterdam (NL)

(11) Embracing Compliance in Robots to Achieve Function (2016) 3D Printing Materials Conference, Maastricht (NL)

(10) Controlling Soft Structures and Devices by Embedded Actuation and Sensing (2015) Designer Matter, AMOLF (NL)

(9) Actuated Materials, Smart Actuated Structures and Devices that Harness Compliance and Instabilities (2015) Aerospace Structures and Computational Mechanics, TU Delft (NL)

(8) Soft Matter Physics Seminar: Mechanical Metamaterials that harness instabilities and folding (2015) Institute Lorentz, Leiden University (NL)

(7) MSME Year End Event: From Origami to Transformable Metamaterials (2015) School of Engineering and Applied Sciences, Harvard University (US)

(6) Guest Lecturer in Computational Material Distributions and Gradients of Compliance (2015) Graduate School of Design, Harvard University (US)

(5) Soft Robotics General Meeting: Finite Element Analysis of Soft Liquid Embedded Strain Sensors (2014) Wyss Institute for Biologically Inspired Engineering, Harvard University (US)

(4) Mech & Math: Instabilities in Pressure-Volume relation of inflatable Membranes (2014) School of Engineering and Applied Sciences, Harvard University (US)

(3) Guest Lecturer in Computational Material Distributions and Gradients of Compliance (2014) Graduate School of Design, Harvard University (US)

(2) Mech & Math: Shape Optimization of Soft Periodic Structures (2012) School of Engineering and Applied Sciences, Harvard University (US)

(1) Abaqus Masterclass (2010) School of Engineering and Applied Sciences, Harvard University (US)


(14) Rational Design of Reconfigurable Prismatic Architected Materials (2017) American Physical Society Meeting. New Orleans, United States. Presentation.

(13) Tension Instability in a thick elastic body (2017) American Physical Society Meeting, New Orleans, United States. Presentation.

(12) Overvelde, J. T. B., Dykstra, D. M. J., de Rooij, R., Weaver, J., Bertoldi, K., (2016). Tensile Instability in a Thick Elastic Body. Soft Matter Meeting. Amsterdam, Netherlands. Soundbite presentation. [pdf]

(11) Overvelde, J. T. B., de Jong, T. A., Becerra S. A., Shevchenko, Y., Whitesides, G. M., Weaver, J., Hoberman C., Bertoldi, K., (2015). Transformable origami-inspired prismatic metamaterials. Wyss retreat. Boston, United States. Movie and demo.

(10) Overvelde, J. T. B., Bertoldi, K., (2015). Amplifying the Response of Soft Actuators by Harnessing Instability. New England Workshop on the Mechanics of Materials and Structures. Boston, United States. Movie.

(9) Overvelde, J. T. B., Kloek, T., D’haen J., Bertoldi, K., (2014). Harnessing Instability in Soft Actuators. AMOLF Designer Matter Workshop International Mechanical Engineering Conference. Amsterdam, The Netherlands. Presentation. [pdf]

(8) Overvelde, J. T. B., de Jong, T. A., Weaver, J., Hoberman, C., Bertoldi, K., (2015). Actuated Origami-like Structures with Tunable Volume and Stiffness. APS March Meeting. San Antonio, United States. Presentation. [pdf]

(7) Overvelde, J. T. B., Kloek, T., D’haen J., Bertoldi, K., (2014). Harnessing Instability in Soft Actuators. ASME International Mechanical Engineering Conference. Montréal, Canada. Presentation. [pdf]

(6) Overvelde, J. T. B., Bertoldi, K., (2014). Putting Soft Sensors to the Test. New England Workshop on the Mechanics of Materials and Structures. Amherst, United States. Movie.

(5) Overvelde, J. T. B., Bertoldi, K., (2013). Topology Optimization of Soft Actuators: Designing Stretchable Inflatable Membranes. ASME International Mechanical Engineering Conference. San Diego, United States. Presentation. [pdf]

(4) Overvelde, J. T. B., Shan, S., Bertoldi, K., (2012). Compaction Through Buckling in 2D Periodic, Soft and Porous Structures: Effect of Pore Shape. New England Workshop on the Mechanics of Materials and Structures. Providence, United States. Movie.

(3) Overvelde, J. T. B., Langelaar M., Keulen, F. van, (2012). The Moving Node Approach in Topology Optimization – An Exploration to a Flow-inspired Meshless Method-based Topology Optimization Method. New England Workshop on the Mechanics of Materials and Structures. Providence, United States. Poster. [pdf]

(2) Overvelde, J. T. B., Shan, S., Bertoldi, K., (2012). Non-linear Response of Soft Porous Structures: Effect of Pore Shape on their Response. Society of Engineering Science – 49th Annual Technical Meeting. Atlanta, United States. Presentation. [pdf]

(1) Overvelde, J. T. B., Langelaar, M., Keulen, F. van, (2012). Influence of the Nodal Distribution on Element-Free Galerkin Accuracy in a Topology Optimization Context. European Congress on Computational Methods in Applied Sciences and Engineering. Vienna, Austria. Presentation. [pdf]


Overvelde, J.T.B., (2016). Embracing Compliance and Instabilities to Achieve Function in Mechanical Metamaterials and Devices. PhD Dissertation – Harvard University. [pdf]

Overvelde, J.T.B., (2012). The Moving Node Approach in Topology Optimization – An Exploration to a Flow-inspired Meshless Method-based Topology Optimization Method. Master’s Thesis – Delft University of Technology. [pdf]


Introduction to Abaqus Script

At Harvard University I worked a lot with Abaqus, there I was the first to start using the Python script interface of Abaqus. Several colleagues asked me to show them how scripting works, so I decided to write a short tutorial about the Abaqus script interface. Since then, the tutorial has been used in an advanced course for Abaqus at Harvard University.

Download the pdf: Learn Abaqus Script In One Hour
Chinese translation: 一小时学会Abaqus脚本  

To get even more acquainted with the Abaqus script interface, I have also added my Matlab and Python files from my project on buckling of periodic structures. These files are only meant to give an example.

Download the files: Example Abaqus Script

Fabrication of Prismatic Architected Materials

Here you can download a description of the fabrication procedure and required vector files to make prototypes of the reconfigurable prismatic architected materials. Using this procedure and the code to generate the vector files all parts can be made, however, figuring out how to connect multiple extruded faces to create the prismatic architected materials is part of the fun and I leave this to you! You should at least get some clues by reading our published article in Nature.

Download the files: Fabrication files and procedure of reconfigurable materials

See also the movie of the fabrication process

Connecting Abaqus to Matlab

I use Abaqus scripting to connect Abaqus with Matlab. I have seen colleagues struggling when writing large text files for the Abaqus input files. This can be avoided by scripting. To learn how to run Abaqus from Matlab and how these programs can interact with each other, you can download the Python script and Matlab files as an example.

Download the files: Abaqus Matlab Connection

Periodic Boundary Conditions in Abaqus

I have written a function in Abaqus script to apply periodic boundary conditions to either 2D or 3D unit cells. This function works well for a rectangular or brick shaped unit cell with not too many elements, but should also work for unit cells with different geometry. The files also contain examples on how to use the function. Make sure to check the final boundary conditions, any comments to improve the function are more than welcome!

Download the files: Periodic Boundary Conditions

Meshless Methods

When writing my Master’s thesis I was working on Meshless Methods. One of the methods I have been working on is the Element-Free Galerkin (EFG) method. Below you can find a Matlab implementation of the EFG method, applied to the exemplary problem of a 2D cantilever beam.

Download the Matlab files: EFG Matlab

Similarly, I have implemented the MLPG mixed collocation method:

Download the Matlab files: MLPG Mixed Collocation Matlab

CFD Matlab

Here I present an implementation of the solution for the discretized 2D incompressible Navier-Stokes equations. I used a collocated grid to discretize the equation. To avoid checkerboard patterns I used a pressure-correction method. The problem that is solved by the Matlab program is the simple 2D pipe flow problem, but boundary conditions can be changed easily.

Download the Matlab files: Navier-Stokes Solver Matlab

Download some documentation of the equations used in the code: Navier-Stokes Discretization Documentation

Fabrication of Tunable Segmented Soft Actuators

My tutorial on Tunable Segmented Soft Actuators has been granted the runner-up prize of the 2016 Soft Robotics Design Competitions in the category for the most significant contribution to fundamental research in soft robotics.

Download all the corresponding files via: Soft Robotics Toolkit