Sensory-Motor Tissues for Soft Robots

Overview

The goal of this project is to generate novel actuators, sensors and materials to enable the creation of future soft robots. These technologies must be able to function under the demanding requirements imposed by highly deformable systems. This includes being able to generate, sense and/or withstand large deformations and forces without breaking. Some of our innovative solutions are discussed below.

Dielectric Elastomer Actuators

We are exploring the creation of new types of soft actuators based on Dielectric Elastomer Actuators (DEAs). DEAs are a type of artificial muscle actuator that exploits electrostatic forces by combining a soft flexible dielectric with stretchable electrodes.

Variable Stiffness Actuator

Controllable stiffness can be an important function for soft robots to exert large forces to environments, and to withstand external loads while keeping their shape. We developed a variable stiffness actuator using DEA and low-melting-point-alloy (LMPA) embedded silicone substrate. The actuator which we call variable stiffness dielectric elastomer actuator (VSDEA) exhibits a bending actuation and a high rigidity change (~90x) between the soft state and the rigid state.

 

Variable stiffness dielectric elastomer actuator (VSDEA)

To demonstrate the usefulness of the actuator, we developed a gripper consisted of two VSDEAs acting as fingers. The gripper showed successful handling of an object where the soft state leads to a better confirmation of the fingers, and the rigid state provides sufficient holding force.

The result will be presented at the 2015 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS), Hamburg, Germany.

This work has been done as a collaboration work with the EPFL-LMTS.

Foldable Antagonistic Actuator

We developed an actuator based on DEA that is capable of antagonistic actuation and passive folding. The actuator enables foldability in robots, and gives robustness to external shocks and overload by its compliance.

Concept of the actuator

We also developed a micro air vehicle (MAV), in which the actuator was used as an elevon to demonstrate its usefulness. The MAV performed fully controlled flights by only the actuators via a remote transmitter with a human pilot.

(left) The elevon actuator, and (right) the folded state of the actuator

This work has been done as a collaboration work with the EPFL-LMTS, and related information can be found on their website.

Soft Grippers based on DEMES

Dielectric Elastomer Minimum Energy Structures (DEMES) are a special type of DEA based on the balance between mechanical and electrical energy. A DEMES device can be fabricated by bonding a stretched DEA to a flexible frame. This composite structure folds up into a minimum energy configuration shown below. When a voltage is applied to the DEA, it expands, returning whole device to the flattened state.

We developed and characterized a prototype of DEMES using silicone type elastomer. Based on the result, two and four-finger gripper are developed.

This work has been done as a collaboration work with the EPFL-LMTS, and related information can be found on their website.

Variable Stiffness Materials

Soft robots are exciting to many applications because they can deform, allowing them to conform to many different surfaces or readily change their shape. However, because they are soft, they can have difficulty holding their position or shape under high external loads. This is why we are interested in developing materials that can controllably change from very soft and flexible to rigid and strong.

One solution that we have developed is a composite material composed of a rigid low-melting-point-alloy (LMPA) microstructure embedded in soft poly(dimethylsiloxane) (PDMS). This material can transition between rigid and soft states by controlling the phase of the LMPA (T= 47°C) through efficient, direct Joule-heating of the LMPA microstructure. This composite material demonstrates a relative stiffness change of >25x (elastic modulus is 40 MPa when LMPA is solid and 1.5 MPa when LMPA is liquid) and a fast transition from rigid to soft states (<1 s) at low power (<500 mW). Additionally, the material possesses inherent state (soft and rigid) and strain sensing (Gauge Factor = 0.8) based on resistance changes.

Publications

2019

Stretchable pumps for soft machines

V. Cacucciolo; J. Shintake; Y. Kuwajima; S. Maeda; D. Floreano et al. 

Nature. 2019-08-22. Vol. 572, p. 516–519. DOI : 10.1038/s41586-019-1479-6.

Delicate yet strong: characterizing the electro-adhesion lifting force with a soft gripper

V. Cacucciolo; J. Shintake; H. Shea 

2019-01-01. 2nd IEEE International Conference on Soft Robotics (RoboSoft), Seoul, SOUTH KOREA, Apr 14-18, 2019. p. 108-113.

2018

All‐Fabric Wearable Electroadhesive Clutch

V. Ramachandran; J. Shintake; D. Floreano 

Advanced Materials Technologies. 2018-10-23. Vol. 4, num. 2, p. 1800313. DOI : 10.1002/admt.201800313.

Variable stiffness strip with strain sensing for wearable robotics

A. Tonazzini; J. Shintake; C. Rognon; V. Ramachandran; S. Mintchev et al. 

2018-07-09. 2018 IEEE International Conference on Soft Robotics (RoboSoft), Livorno, April 24-28, 2018. p. 485-490. DOI : 10.1109/ROBOSOFT.2018.8405373.

Soft Biomimetic Fish Robot Made of Dielectric Elastomer Actuators

J. Shintake; V. Cacucciolo; H. Shea; D. Floreano 

Soft Robotics. 2018-06-29. Vol. 5, num. 4, p. 466-474. DOI : 10.1089/soro.2017.0062.

Bioinspired dual-stiffness origami

S. Mintchev; J. Shintake; D. Floreano 

Science Robotics. 2018. Vol. 3, num. 20. DOI : 10.1126/scirobotics.aau0275.

Soft Robotic Grippers

J. Shintake; V. Cacucciolo; D. Floreano; H. Shea 

Advanced Materials. 2018. Vol. 30, num. 29, p. 1707035. DOI : 10.1002/adma.201707035.

Ultra-stretchable strain sensors using carbon black-filled elastomer composites and comparison of capacitive versus resistive sensors

J. Shintake; E. Piskarev; S. Jeong; D. Floreano 

Advanced Materials Technologies. 2018. Vol. 3, p. 1700284. DOI : 10.1002/admt.201700284.

2017

Spectrally resolved nonlinearity and temperature dependence of perovskite solar cells

M. Mundus; B. Venkataramanachar; R. Gehlhaar; M. Kohlstaedt; B. Niesen et al. 

Solar Energy Materials And Solar Cells. 2017. Vol. 172, p. 66-73. DOI : 10.1016/j.solmat.2017.07.013.

Bio-inspired Tensegrity Soft Modular Robots

D. Zappetti; S. Mintchev; J. Shintake; D. Floreano 

2017. Living Machines 2017, Palo Alto, California, USA, July 25-28, 2017. p. 497-508.

Development of Bio-inspired Underwater Robot with Adaptive Morphology Capable of Multiple Swimming Modes

T. A. P. Paschal; J. Shintake; S. Mintchev; D. Floreano 

2017. IEEE/RSJ International Conference on Intelligent Robots and Systems, Vancouver, Canada, September 24–28.

Soft Pneumatic Gelatin Actuator for Edible Robotics

J. Shintake; H. A. Sonar; E. Piskarev; J. Paik; D. Floreano 

2017. IEEE/RSJ International Conference on Intelligent Robots and Systems, Vancouver, Canada, September 24–28.

Foldable Drones: from Biology to Technology

D. Floreano; S. Mintchev; J. Shintake 

2017. SPIE Bioinspiration, Biomimetics, and Bioreplication, Portland, Oregon, March 2017. p. 1016203-1-1016203-6. DOI : 10.1117/12.2259931.

2016

Biomimetic Underwater Robots Based on Dielectric Elastomer Actuators

J. Shintake; H. Shea; D. Floreano 

2016. IEEE/RSJ International Conference on Intelligent Robots and Systems, Daejeon, Korea, October 9-14. p. 4957-4962.

Variable Stiffness Fiber with Self-Healing Capability

A. Tonazzini; S. Mintchev; B. Schubert; B. Mazzolai; J. Shintake et al. 

Advanced Materials. 2016. Vol. 28, num. 46, p. 10105. DOI : 10.1002/adma.201602580.

Dielectric Elastomers as EAPs: How to start experimenting with them

H. Shea; A. Koh; I. Graz; J. Shintake 

Electromechanically Active Polymers; Springer, 2016.

Soft compliant gripper for safe manipulation of extremely fragile objects

H. Shea; J. Shintake; D. Floreano 

SPIE Newsroom. 2016. DOI : 10.1117/2.1201603.006409.

Functional Soft Robotic Actuators Based on Dielectric Elastomers

J. Shintake / D. Floreano; H. Shea (Dir.)  

Lausanne, EPFL, 2016. 

Versatile soft grippers with intrinsic electroadhesion based on multifunctional polymer actuators

J. Shintake; S. Rosset; B. E. Schubert; D. Floreano; H. Shea 

Advanced Materials. 2016. Vol. 28, num. 2, p. 231-238. DOI : 10.1002/adma.201504264.

2015

Variable Stiffness Actuator for Soft Robotics Using Dielectric Elastomer and Low-Melting-Point Alloy

J. Shintake; B. E. Schubert; S. Rosset; H. Shea; D. Floreano 

2015. International Conference on Intelligent Robots and Systems, Hamburg, Germany, September 28 – October 02, 2015. p. 1097-1102. DOI : 10.1109/IROS.2015.7353507.

DEA for soft robotics: 1-gram actuator picks up a 60-gram egg

J. Shintake; S. Rosset; B. E. Schubert; S. Mintchev; D. Floreano et al. 

2015. Electroactive Polymer Actuators and Devices (EAPAD), San Diego, March 2015. p. 94301S. DOI : 10.1117/12.2084043.

A Foldable Antagonistic Actuator

J. Shintake; S. Rosset; B. E. Schubert; D. Floreano; H. Shea 

IEEE/ASME Transactions on Mechatronics. 2015. Vol. 20, num. 5, p. 1997-2008. DOI : 10.1109/TMECH.2014.2359337.

Rollable Multisegment Dielectric Elastomer Minimum Energy Structures for a Deployable Microsatellite Gripper

S. Araromi; I. Gavrilovich; J. Shintake; S. Rosset; M. Richard et al. 

IEEE/ASME Transactions on Mechatronics. 2015. Vol. 20, num. 1, p. 438. DOI : 10.1109/TMECH.2014.2329367.

2014

Model and design of dielectric elastomer minimum energy structures

S. Rosset; S. Araromi; J. Shintake; H. Shea 

Smart Materials and Structures. 2014. Vol. 23, num. 8, p. 085021. DOI : 10.1088/0964-1726/23/8/085021.

Stretchable Electroadhesion for Soft Robots

J. M. Germann; B. E. Schubert; D. Floreano 

2014. IEEE/RSJ International Conference on Intelligent Robots and Systems, Chicago, Illinois, USA, September 14-18, 2014.

Towards a deployable satellite gripper based on multisegment dielectric elastomer minimum energy structures

S. Araromi; I. Gavrilovich; J. Shintake; S. Rosset; H. Shea 

2014. Electroactive Polymer Actuators and Devices (EAPAD) 2014, San Diego, March 2014. p. 90562G. DOI : 10.1117/12.2044667.

2013

Dielectric Elastomer Actuators for soft-grasping

J. Shintake; S. Rosset; B. E. Schubert; D. Floreano; H. Shea 

International Workshop on Soft Robotics and Morphological Computation, Centro Stefano Franscini (CSF), Monte Verità, Ascona, Switzerland, July 14-19, 2013.

Variable stiffness material based on rigid low-melting-point-alloy-microstructures embedded in soft poly(dimethylsiloxane) (PDMS)

B. E. Schubert; D. Floreano 

RSC Advances. 2013. Vol. 3, num. 46, p. 24671-24679. DOI : 10.1039/c3ra44412k.

Artificial muscles for soft robots

J. Shintake; S. Rosset; D. Floreano; H. Shea 

Festival de robotique.

Effect of mechanical parameters on dielectric elastomer minimum energy structures

J. Shintake; S. Rosset; D. Floreano; H. Shea 

2013. Electroactive Polymer Actuators and Devices (EAPAD), San Diego, USA, March 10, 2013. p. 86872V. DOI : 10.1117/12.2009368.

2012

A soft robotic actuator using dielectric minimum energy structures

J. Shintake; S. Rosset; D. Floreano; H. Shea 

2nd International Conference on Electromechanically Active Polymer (EAP) transducers & artificial muscles, Potsdam (Berlin), Germany, May 29-30, 2012.