Dr Samuel Rosset
Research | Current
Dielectric elastomer actuators (DEAs) for biomedical applications
Cells in our body are constantly submitted to mechanical strain and stress. Cells react to these mechanical cues by activating signal pathways (mechanotransduction), by orientating relative to the direction of traction, by differentiating, etc. These mechanically-induced responses are difficult to reporoduce in vitro, as cells are usually cultured in rigid Petri dishes. Soft actuators enables to culture cells on a stretchable membrane, which can be locally deformed by the application of an electrical signal, thus stretching the cells that are cultured on it.
Current projects related to mechanotransduction:
1) Understanding the effect of traumatic brain-injury on the cell level
Dr. Vickie Shim is leading a multiscale study of traumatic brain injury at ABI. In this context, we are using soft actuators to submit 2D brain cell cultures and tissue explants to mechanical loading reproducing the strain and strain rate experienced in case of a TBI event. The objective is to study the response of the cells to the mechanical insult and identify the damage threshold.
2) Optogenetics platform
In the frame of a collaboration with EPFL Switzerland and Boston University (Dr. Matthias Imboden), we are working on an in-vitro optogenetics platform combining localised illumination of a cell culture through a laser beam and a multi-axis optical microelectromechanical system (MEMS) mirror.
The platform combines the unprecedented ability to stretch cells and to selectively illuminate specific cells using the steerable laser-beam, thus enabling light-activated protein expression of genetically modified cells. A master project is available to develop this novel research platform.
Dielectric elastomer actuators are easy to make: take a membrane of 3M VHB tape, stretch it on a frame, apply some carbon poweder to serve as compliant electrodes and that's it. However, lifetime and reproducibility of such devices is low. How to make reliable DEAs? How to precisely pattern compliant electrodes on a thin suspended membrane? I am interested in all aspects of reliable fabrication of DEAs, and especially by the patterning of the compliant electrodes. I have worked with electrodes made by metal ion implantation, pad printing, spray-coating and inkjet printing.
Modelling and characterisation of soft actuators
I work on different modelling aspects of dielectric elastomer actuators. How to suppress the viscoelastic drift?, How to characterise the ageing and degradation of the electrodes? How to optimise the actuation of DEAs in specific configurations?
High Voltage Electronics
Dielectric elastomer actuators work with high electric fields, but low power. There is a lack of commercial power supply that combine the required properties (generation of high voltage, possibility to generate HV square signals with high slew rate, easily programmable, lighy & compact, etc.) at an affordable price. We have consequently developped a High Voltage power supply (HVPS), which is specifically designed to drive electrostatic actuators. We have released the project with an open source license: project Peta-pico-Voltron.
Teaching | Current
ENGSCI-753: Computational Techniques in Continuum Mechanics and Bioengineering
BIOMENG-241: Instrumentation and Design
Current Postgraduate Students:
- Masoumeh Hesam Mahmoudinezhad (PhD): Soft compression sensors
- Derek Orbaugh (PhD): Using hand gestures to control an underwater drone.
- Yi-Han Wu (PhD): Mechanical loading of brain cells
- Yilei Shi (PhD): Touch interaction
- Sahan Jayatissa (PhD): High-throughput cell-stretching device
- Yuting Zhu (PhD): Multi-touch capacitive sensing
- Antony Tang (Ms): Wearable haptic feedback
Current undergraduate Students:
- Lucy Shen and Jake Kelly-Hulse (Part IV): Modelling of an electroadhesive pad
Former postgraduate Students:
- Samuel Schlatter (PhD, EPFL, 2020): Inkjet printing of soft machines
- Sahan Jayatissa (Ms, 2019): Inkjet printing as a Fabrication Tool for Dielectric Elastomer Actuator Electrodes and Microfluidics
- Nadine Besse (PhD, EPFL, 2018): Large Array of Shape Memory Polymer Actuators for Haptics and Microfluidics
- Alexandre Poulin (PhD, EPFL, 2016): Miniaturized Dielectric Elastomer Actuator for Mechanical Stimulation of Monolayer Cell Cultures
- Luc Maffli (PhD, EPFL, 2014): Fluidically-coupled dielectric elastomer actuator structures for tunable optics and microfluidics
- Samin Akbari (PhD, EPFL, 2013): Arrays of dielectric elastomer microactuators for cell mechanotransduction
- Amirhossein Vahabzadeh (Ms, EPFL, 2013): Local stiffening of soft elastomer membranes for anisotropic actuation.
- François Guélat (MS, EPFL, 2007): Biologically inspired micro-drill for future planetary exploration.
Former undergraduate Students
- Henry Flint & Mairi Robertson (partIV, 2019): Dielectric Elastomers for use with Cardiac myocytes
- Stephen Kyi-Xiang Leong & Anthony Tang (PartIV, 2019): Hand Gesture Control of Quadcopter Drones
- Lucy Yan & Ieuan Edmonds (PartIV, 2018): Robotic Finger Exoskeleton for In-Home Hemiplegic Stroke Rehabilitation of Hand Dexterity
- Selim Gatti (EPFL, Lycee Denis de Rougemont, 2017):
- Simon Vuilleumier (EPFL, 2014): Measurement setup to characterize the degradation of compliant electrodes when submitted to stretch.
- President of the Outreach and Dissemintation committee of the EuroEAP society
- Chair of ABI health and Safety committee (2019)
- Member of ABI Health and Safety committee (2019-Present)
- Chair of the ABI sustainability committee (2019 - Present)
- Member of ABI Research Forum committee (2018-2020)
Areas of expertise
- Soft transducers
- Fabrication processes
Selected publications and creative works (Research Outputs)
- Imboden, M., de Coulon, E., Poulin, A., Dellenbach, C., Rosset, S., Shea, H., & Rohr, S. (2019). High-speed mechano-active multielectrode array for investigating rapid stretch effects on cardiac tissue. Nature communications, 10 (1)10.1038/s41467-019-08757-2
- Poulin, A., & Rosset, S. (2019). An open-loop control scheme to increase the speed and reduce the viscoelastic drift of dielectric elastomer actuators. EXTREME MECHANICS LETTERS, 27, 20-26. 10.1016/j.eml.2019.01.001
- Schlatter, S., Illenberger, P., & Rosset, S. (2018). Peta-pico-Voltron: An open-source high voltage power supply. HardwareX, 4.10.1016/j.ohx.2018.e00039
- Poulin, A., Imboden, M., Sorba, F., Grazioli, S., Martin-Olmos, C., Rosset, S., & Shea, H. (2018). An ultra-fast mechanically active cell culture substrate. Scientific reports, 8 (1)10.1038/s41598-018-27915-y
- McCoul, D., Rosset, S., Schlatter, S., & Shea, H. (2017). Inkjet 3D printing of UV and thermal cure silicone elastomers for dielectric elastomer actuators. Smart Materials and Structures, 26 (12), 125022-125022. 10.1088/1361-665X/aa9695
- Marette, A., Poulin, A., Besse, N., Rosset, S., Briand, D., & Shea, H. (2017). Flexible zinc-tin oxide thin film transistors operating at 1 kV for integrated switching of dielectric elastomer actuators arrays. Advanced Materials, 29 (30)10.1002/adma.201700880
- Poulin, A., Saygili Demir, C., Rosset, S., Petrova, T., & Shea, H. (2016). Dielectric elastomer actuator for mechanical loading of 2D cell cultures. Lab on a Chip, 16 (19), 3788-3794. 10.1039/c6lc00903d
- Rosset, S., & Shea, H. R. (2016). Small, fast, and tough: Shrinking down integrated elastomer transducers. Applied Physics Reviews, 3 (3), 031105-031105. 10.1063/1.4963164