The Life Events of The Neithal People in the Collection of Short Stories 'Vidiyalin Veliccham (the Light of the Dawn)’ and 'Velappaadu (Work Nature)'

After reading J. Jacqueline Mary’s book ‘Emperors of Ocean are Fishermen’ I got a clear idea about the life style of the Neithal land people and fishermen around Kanyakumari district. Two novels from folklore literature have been taken up for study. The novels were written by Neithal land writers and it is about the true incidents which they saw and experienced. The novels are Saptika’s ‘Vidiyalil Velicham’ and Irayuman Sagar’s ‘Velapadu’. ‘Vidiyalil Velicham’ tells about the honorable marriages and its consequences ‘Velapadu’ depicts the superstitious beliefs, social ostracism, drug habits, about the irresponsibility of youths, youths who think their parents as burden, borrowing money and fulfilling their needs, beliefs about witchcraft, wrong directions given by police and lack of awareness about the law. Ten short stories in Irayuman’s ‘Velapadu’ gives a clear note about the life events of Neithal land people

Development and characterization of a new silicone/platine based 2- DoF sensorized end-effector for micromanipulators.

International audienceThis paper reports the development and the characterization of a new silicone end-effector with integrated sensor based on a set of platine piezoresistive gage. Used as interface between a micromanipulator or actuator and a manipulated small object, the features of the end-effector are: 1) its compactness (length between 750μm and 2mm, width=40μm, thickness=25μm), 2) the fully integrated force measurement system thanks to microfabricated platine piezoresistive gage, 3) the 2-dof (degrees of freedom: along y and z axis) measurement capability, 4) thehigh sensitivity of measurment provided for each axis (0.6% to 0.8% for the range of measured force of 1mN), 4) and the relatively high gauge factor (G=6). This paper reports the principle, the development, the microfabrication and the characterization of the 2-dof sensorized end-effector.silicone/platine (Si/Pt) end-effector, sensorized end-effector, Platine strain gage, micromanipulation, microfabrication, 2 degrees of freedom, force measurement

Micro-manipulation of silicate micro-sized particles for biological applications.

International audienceThere are great challenges in biological research to study mechanical or chemical interactions between biological objects and artificial parts, to analyse the biocompatibility of artificial materials and/or to increase knowledge about biological cells. Some interaction studies between cells and artificial objects require to positioning very small objects whose typical size is comparable with cell's size (typically 5-20 micrometers). This paper presents design, building and testing of a new micro-manipulation station able to grasp, transport and release ten micrometers objects. Devoted to an existing piezoelectric microgripper, innovative end-effectors in silicon have been designed after several mechanical studies. They have been built with microfabrication processes (DRIE1) in SOI 2 wafers. For the application, the positioning of silicate crystals which contain iron close to E-Coli bacteria, new end-effectors were glued on the piezoelectric microgripper. Mounted on a three axis micropositioning stage under a videomicroscope, this innovative microgripper is able to grasp a silicate crystal of 15 micrometers in the aire and release it in the bacteria liquid medium

Feedforward and IMC-feedback control of a nonlinear 2-DOF piezoactuator dedicated to automated micropositioning tasks.

International audienceThis paper presents the characterization, modeling and precise control of a 2-dof piezoactuator dedicated to precise and automated micropositioning tasks. The piezoactuator is characterized by a strong hysteresis and a high coupling between the two axes making the synthesis of a controller very difficult. We therefore propose to compensate first the hysteresis (feedforward control) in order to obtain an approximate linear system. Afterwards, an internal model control (IMC) structure is applied (feedback control) to enhance the performances of the piezoactuator. The main advantage of the proposed approach is its simplicity both for computation and for implementation making it very convenient for realtime embedded systems. Finally, the experimental results demonstrate its efficiency and conveniency for precise positioning

Electron-electron interactions in nano-patterned La 0.3 Sr 0.7 MnO 3 thin films

International audienceUnderstanding the transport in ultra-thin epitaxial La0.3Sr0.7MnO3 (LSMO) is a topic widespread current interest. Here we explore electron-electron interactions in low temperature magneto-transport in straight and zigzag nanowires fabricated from ultra-thin epitaxial LSMO films grown to different thicknesses on STO(100) substrates. We find that three-dimensional electron-electron interactions can explain the resistivity upturn, including many of the changes observed with film thickness, nano-patterning, and magnetic field

Overview of microgrippers and design of a micro-manipulation station based on a MMOC microgripper

International audienceThis paper deals with an overview of recent microgrippers. As the end-effectors of micromanipulation systems, microgrippers are crucial point of such systems for their efficiency and their reliability. The performances of current microgrippers are presented and offer a stroke extending from 50 m to approximately 2mm and a maximum forces varying from 0,1mN to 600 mN. Then, micromanipulation system based on a piezoelectric microgripper and a SCARA robot is presented

Dry etching of single crystal PMN-PT piezoelectric material.

International audienceDuring the last decade, the applications of PMN-PT spread significantly. Unlike PZT, the appropriate microtechnologies for PMN-PT Piezo-MEMS aren't fully documented in the literature. This paper deals with the PMN-PT etching by inductively coupled plasma (ICP) technique, also known as DRIE. The paper quantitatively presents the etching parameters of PMN-PT by the Ar/C4F8 gas combination and reports some related useful experience

Mechanical de-tethering technique for Silicon MEMS etched with DRIE process.

International audienceGetting Micro-Electro-Mechanical Systems (MEMS) out of a wafer after fabrication processes is of great interest in testing, packaging or simply using these devices. Actual solutions require special machines like wafer dicing machines, increasing time and cost of de-tethering MEMS. This article deals with a new solution for manufacturing mechanical de-tetherable silicon MEMS. The presented solution could be done with DRIE process, already used in silicon MEMS fabrication, without additional time or cost. We are proposing a new way to create a notch on tethers linking both wafer and millimetric MEMS, especially designed to break with a specified mechanical force. A theoretical silicon fracture study, the experimental results and dimensional rules to design the tethers are presented in this article. This new technique is particularly useful for microscopic MEMS parts, and will find applications in the field of the MEMS components micro-assembly