Publications de Christophe Yamahata

DNA Manipulation Based on Nanotweezers

Springer Netherlands2016

Capillary-valve-based platform towards cell-on-chip mechanotransduction assays

Hicham Majd, Dominique Pioletti, Christophe Yamahata, Martinus Gijs, Tanja Cloé Hausherr, Arnaud Müller

Reliable in vitro models are required to understand the ability of cells to respond and adapt to mechanical stimuli. To mimic and interface with the microenvironment, lab-on-a-chip devices and microelectromechanical systems (MEMS) provide excellent options ...

Elsevier2013

High-angular-range electrostatic rotary stepper micromotors fabricated with SOI technology

Christophe Yamahata, Martinus Gijs, Marc Stranczl

Flexible bearings are advantageous for microelectromechanical systems as they enable precise, accurate, repeatable, and reliable motion without frictional contact. Based on the principle of a rotary folded-beam suspension, we have designed, fabricated, mod ...

Institute of Electrical and Electronics Engineers2012

DNA Manipulation Based on Nanotweezers

Christophe Yamahata

Characterization of DNA molecules by mechanical tweezers ...

Springer Science+Business Media2012

Temporally aliased video microscopy: an undersampling method for in-plane modal analysis of microelectromechanical systems

Christophe Yamahata, Martinus Gijs, Marc Stranczl

A simple optical method is proposed for performing in-plane experimental modal analysis of micromachined structures with a conventional charge-coupled device (CCD) camera. The motion of a micromechanical device actuated by high frequency sinusoidal forces ...

Institute of Electrical and Electronics Engineers2012

Modal analysis and modeling of a frictionless electrostatic rotary stepper micromotor

Christophe Yamahata, Martinus Gijs, Marc Stranczl

We present the design, modeling and characterization of a 3-phase electrostatic rotary stepper micromotor. The proposed motor is a monolithic device fabricated using silicon-on-insulator (SOI) technology. The rotor is suspended with a frictionless flexural ...

IEEE2011

Subpixel translation of MEMS measured by discrete Fourier transform analysis of CCD images

Christophe Yamahata, Martinus Gijs, Marc Stranczl

We present a straightforward method for measuring in-plane linear displacements of microelectromechanical systems (MEMS) with a subnanometer resolution. The technique is based on Fourier transform analysis of a video recorded with a Charge-Coupled Device ( ...

2011

Subnanometer translation of microelectromechanical systems measured by discrete Fourier analysis of CCD images

Christophe Yamahata, Martinus Gijs

In-plane linear displacements of microelectromechanical systems are measured with subnanometer accuracy by observing periodic micropatterns with a CCD camera attached to an optical microscope. The translation of the microstructure is retrieved from the vid ...

Institute of Electrical and Electronics Engineers2010

Miniaturized PMMA ball-valve micropump with cylindrical electromagnetic actuator

Christophe Yamahata, Martinus Gijs, Meng Shen

We have fabricated and characterized a reciprocating poly(methylmetacrylate) (PMMA) ball-valve micropump actuated with a miniaturized cylindrical electromagnetic circuit. By finite element calculations, we have optimized the structure of the electromagnet ...

2008

A high-performance compact electromagnetic actuator for a PMMA ball-valve micropump

Christophe Yamahata, Martinus Gijs, Meng Shen

We present the microfabrication and characterization of a reciprocating-type poly(methylmetacrylate) (PMMA) ball-valve micropump which is actuated with a high-performance and compact electromagnetic circuit of centimeter size. We have improved by finite el ...

Institute of Physics2008

Miniaturized PMMA ball-valve micropump with cylindrical electromagnetic actuator

Christophe Yamahata, Martinus Gijs, Meng Shen

2007

Pumping of mammalian cells with a nozzle-diffuser micropump

Christophe Yamahata, Horst Vogel, Martinus Gijs, Caroline Vandevyver, Paulina Izewska, Frédéric Lacharme

We discuss the successful transport of jurkat cells and 5D10 hybridoma cells using a reciprocating micropump with nozzle-diffuser elements. The effect of the pumping action on cell viability and proliferation, as well as on the damaging of cellular membran ...

Royal Society of Chemistry2005

Plastic Micropump with ferrofluidic actuation

Christophe Yamahata, Heinrich Hofmann, Mathieu Chastellain, Martinus Gijs, Alke Fink, Virendra Kumar Parashar

Institute of Electrical and Electronics Engineers2005

A PMMA valveless micropump using electromagnetic actuation

Christophe Yamahata, Martinus Gijs

We have fabricated and characterized a polymethylmethacrylate (PMMA) valveless micropump. The pump consists of two diffuser elements and a polydimethylsiloxane (PDMS) membrane with an integrated composite magnet made of NdFeB magnetic powder. A large-strok ...

2005

Magnetically actuated micropumps

Christophe Yamahata

"Lab-On-a-Chip" (LOC) systems are intended to transpose complete laboratory instrumentations on the few square centimetres of a single microfluidic chip. With such devices the objective is to minimize the time and cost associated with routine biological an ...

EPFL2005

Glass valveless micropump using electromagnetic actuation

Christophe Yamahata, Martinus Gijs, Frédéric Lacharme

We present a valveless micropump in glass, which is magnetically actuated using the sinusoidal current of an external electromagnet. We employ a powder blasting microerosion process for microstructuring the glass substrates and fusion bonding for assembly ...

2005

Electromagnetically Actuated Ball Valve Micropumps

Christophe Yamahata, Martinus Gijs, Frédéric Lacharme

We present two types of oscillating diaphragm micropumps configured with passive ball valves and using electromagnetic actuation. One type is made out of poly(methyl methacrylate) (PMMA), while the other one is made out of borosilicate glass. Both were pro ...

2005

A ball valve micropump in glass fabricated by powder blasting

Christophe Yamahata, Martinus Gijs, Frédéric Lacharme

We present the microfabrication and characterisation of a ball valve micropump in glass, which is magnetically actuated using the sinusoidal current of an external electromagnet. We employ the use of a simple powder blasting technology for microstructuring ...

2005