A Review of Haptic Feedback Teleoperation Systems for Micromanipulation and Microassembly

International audienceThis paper presents a review of the major haptic feedback teleoperation systems for micromanipulation. During the last decade, the handling of micrometer-sized objects has become a critical issue. Fields of application from material science to electronics demonstrate an urgent need for intuitive and flexible manipulation systems able to deal with small-scale industrial projects and assembly tasks. Two main approaches have been considered: fully automated tasks and manual operation. The first one require fully pre determined tasks, while the later necessitates highly trained operators. To overcome these issues the use of haptic feedback teleoperation where the user manipulates the tool through a joystick whilst feeling a force feedback, appears to be a promising solution as it allows high intuitiveness and flexibility. Major advances have been achieved during this last decade, starting with systems that enable the operator to feel the substrate topology, to the current state-of-the-art where 3D haptic feedback is provided to aid manipulation tasks. This paper details the major achievements and the solutions that have been developed to propose 3D haptic feedback for tools that often lack 3D force measurements. The use of virtual reality to enhance the immersion is also addressed. The strategies developed provide haptic feedback teleoperation systems with a high degree of assistance and for a wide range of micromanipulation tools. Based on this expertise on haptic for micromanipulation and virtual reality assistance it is now possible to propose microassembly systems for objects as small as 1 to 10 micrometers. This is a mature field and will benefit small-scale industrial projects where precision and flexibility in microassembly are required

Manipulation aux échelles microscopiques.

National audienceLa manipulation robotique aux échelles microscopiques représente un enjeu majeur pour le développement des techniques biologiques et pour l'avènement de produits hautement miniaturisés réalisés par micro-assemblage. La miniaturisation d'un système de manipulation est confrontée à plusieurs ruptures de type physique ou technique, comme par exemple la prédominance des forces d'adhésion sur le comportement des micro-objets ou le changement des techniques de fabrication influençant fortement les méthodes de conception des microrobots. L'objet de l'étude de la manipulation aux échelles microscopiques porte sur la recherche de méthodes robotiques adaptées à ce nouveau paradigme : le micromonde. La compréhension et la modélisation de ce micromonde sont un corollaire essentiel à l'étude de stratégies robotiques adaptées. Basées sur cette modélisation, de nouvelles stratégies de manipulation sont étudiées en prenant en compte les comportements particuliers des micro-objets tel que les collages sur les organes terminaux. La mise en oeuvre de ces stratégies de manipulation nécessite une structure robotique complète incluant des systèmes de perception et de contrôle de l'environnement. La commande de l'ensemble soit par téléopération avec retour haptique soit en cycle automatique est enfin également un enjeu scientifique

Flows at the Edge of an Active Region: Observation and Interpretation

Upflows observed at the edges of active regions have been proposed as the source of the slow solar wind. In the particular case of Active Region (AR) 10942, where such an upflow has been already observed, we want to evaluate the part of this upflow that actually remains confined in the magnetic loops that connect AR10942 to AR10943. Both active regions were visible simultaneously on the solar disk and were observed by STEREO/SECCHI EUVI. Using Hinode/EIS spectra, we determine the Doppler shifts and densities in AR10943 and AR10942, in order to evaluate the mass flows. We also perform magnetic field extrapolations to assess the connectivity between AR10942 and AR10943. AR10943 displays a persistent downflow in Fe XII. Magnetic extrapolations including both ARs show that this downflow can be connected to the upflow in AR10942. We estimate that the mass flow received by AR10943 areas connected to AR10942 represents about 18% of the mass flow from AR10942. We conclude that the upflows observed on the edge of active regions represent either large-scale loops with mass flowing along them (accounting for about one-fifth of the total mass flow in this example) or open magnetic field structures where the slow solar wind originates.Comment: 20 pages, 9 figures, accepted for publication in Astrophys.

Characterizing piezoscanner hysteresis and creep using optical levers and a reference nanopositioning stage.

International audienceA method using atomic force microscope (AFM) optical levers and a reference nanopositioning stage has been developed to characterize piezoscanner hysteresis and creep. The piezoscanner is fixed on a closed-loop nanopositioning stage, both of which have the same arrangement on each axis of the three spatial directions inside the AFM-based nanomanipulation system. In order to achieve characterization, the optical lever is used as a displacement sensor to measure the relative movement between the nanopositioning stage and the piezoscanner by lateral tracking a well-defined slope with the tapping mode of the AFM cantilever. This setup can be used to estimate a piezoscanner's voltage input with a reference displacement from the nanopositioning stage. The hysteresis and creep were accurately calibrated by the method presented, which use the current setup of the AFM-based nanomanipulation system without any modification or additional devices

A resonant structure designed for probing the elastic properties of suspension and adherent cells in liquid environments

9 ppInternational audienceThis paper presents a novel force sensitive structure exploiting a dynamic mode for probing the elastic properties of living cells. A key feature of this structure is the possibility of conducting measurements in liquid environments while keeping high dynamic performances. The structure indeed provides a steady area that can be adapted so that suspension or adherent cells can be placed in a culture medium. The steady area is also connected to two adjacent beam resonators. Because these resonators never need to be immersed into the culture medium during measurements, forces applied to cells can be estimated with a high sensitivity via frequency shifts. In this paper, we conduct an extensive theoretical analysis to investigate the nonlinear effects of large static pre-deflections on the dynamic behavior of the structure. As a proof of concept, we also report the fabrication, characterization and calibration of the first prototype intended to deal with suspension cells with a diameter ranging from 100 to 500 μm. This prototype currently offers a quality factor of 700 and a force sensitivity of ∼2.6 HzmN−1. We also demonstrate that the prototype is capable of measuring the elastic modulus of biological samples in a rapid and sufficiently accurate manner without the need of a descriptive model

Microrobotique pour composants micrométriques : les challenges pour leur manipulation et leur assemblage.

National audienceLa miniaturisation de nombreux produits manufacturés est une réalité et ce processus s'accentue. Ceci conduit la communauté scientifique à proposer des systèmes de production permettant de fabriquer des systèmes hybrides, c'est-à-dire dont les composants proviennent de plusieurs processus de fabrication ou de microfabrication, et ayant des structures 3D complexes afin d'intégrer plusieurs fonctions dans des volumes les plus réduits possibles. Le micro-assemblage réalisé avec des systèmes microrobotiques est une réponse pertinente à ce besoin de produits micromécatroniques. A travers une présentation des principales activités dans ce domaine dans le monde, on peut constater que la mise en oeuvre réelle de systèmes pour manipuler et assembler de façon automatisée (ou en partie) des composants sous-millimétriques reste un véritable challenge si l'on veut cumuler des propriétés de haute précision, de fiabilité, de productivité et de flexibilité. D'autre part, l'intérêt de groupes industriels Européens et l'émergence de start-ups montrent que l'assemblage de composants de taille sousmillimétrique est un enjeu sociétal. En terme de prospective, le passage de la barrière dimensionnelle des 10

Modeling and Swimming Property Characterizations of Scaled-Up Helical Microswimmers.

International audienceMicro- and nanorobots capable of controlled propulsion at low Reynolds number are foreseen to change many aspects of medicine by enabling targeted diagnosis and therapy, and minimally invasive surgery. Several kinds of helical swimmers with different heads actuated by a rotating magnetic field have been proposed in prior works. Beyond these proofs of concepts, this paper aims to obtain an optimized design of the helical swimmers adapted to low Reynolds numbers. For this, we designed an experimental setup and scaled-up helical nanobelt swimmers with different head and tail coatings to compare their rotational propulsion characteristics.We found in this paper that the head shape of a helical swimmer does not influence the shape of the rotational propulsion characteristics curve, but it influences the cutoff frequency values.The rotational propulsion characteristics of the helical swimmers with a magnetic head or a magnetic tail are different. The helical swimmers with uniformly coated magnetic tails do not show a cutoff frequency, whereas the ones with a magnetic head exhibit a saturation of frequency

Optimization of the size of a magnetic microrobot for high throughput handling of micro-objects.

International audienceOne of the greatest challenges in microrobotic is to handle individually a large number of objects in a short time, for applications such as cell sorting and assembly of microcomponents. This ability to handle a large number of microobjects is directly related to the size of the microrobot. This paper proposes a theoretical study of the size of a magnetic microrobot maximizing its capacity of displacement. It demonstrates that there is an optimal size can be obtained, due to a trade-off between the inertial and the viscous effects. Analyticalexpressions of the optimal size and the related frequency of motion are derived from a simplified model to highlight the influence of the geometrical and the physical parameters of the magnetic manipulation system such as the viscosity of the liquid and the size of the workspace. A numerical simulation validates the analytical analysis and demonstrates a high displacement capacity of the microrobot (around 100 back and forth motions per second for a robot of around 20 µm in water)

Analysis of forces for micromanipulations in dry and liquid media.

International audienceDuring microscale object manipulation, contact (pull-off) forces and non-contact (capillary, van der Waals and electrostatic) forces determine the behaviour of the micro-objects rather than the inertial forces. The aim of this article is to give an experimental analysis of the physical phenomena at a microscopic scale in dry and liquid media. This article introduces a review of the major differences between dry and submerged micromanipulations. The theoretical influences of the medium on van der Waals forces, electrostatic forces, pull-off forces and hydrodynamic forces are presented. Experimental force measurements based on an AFM system are carried out. These experiments exhibit a correlation better than 40 % between the theoretical forces and the measured forces (except for pull-off in water). Finally, some comparative experimental micromanipulation results are described and show the advantages of the liquid medium

The rotational propulsion characteristics of scaled-up helical microswimmers with different heads and magnetic positioning.

International audienceMicro and nanorobots capable of controlled propulsion at low Reynolds number are foreseen to change many aspects of medicine by enabling targeted diagnosis and therapy, and minimally invasive surgery. Several kinds of helical swimmers with different heads actuated by a rotating magnetic field have been proposed in prior works. Beyond these proofs of concepts, this paper aims to study behaviours of helical swimmers with different head and magnetic positing adapted to low Reynolds number liquids. For this, we designed an experimental setup and scaled-up helical nanobelt swimmers with different heads and tail coatings to compare their rotational propulsion characteristics. We found in this paper that the head shape of a helical swimmer does not influence on the shape of the rotational propulsion characteristics curve, but it influences on the values of the cut-off frequency. The rotational propulsion characteristics of helical swimmers with a magnetic head or a magnetic tail are much different. The helical swimmer with uniformly coated magnetic tail does not show a cut-off frequency but a saturation of frequency