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Academic Freedom of the Chair

(Text available in French only)

Liberté académique

La chaire jouit sans restriction de la liberté académique.

« La liberté académique est un héritage intellectuel des anciennes écoles et pensées philosophiques qui ont donné lieu à la fondation des universités […]. Elle a prouvé être au cours des siècles, une condition essentielle pour les fonctions primaires des universités et des institutions éducatives en général, comme la recherche et l’enseignement […]. Cette liberté rend possible l’esprit critique propre aux institutions universitaires à travers leur histoire. Ces institutions ont absolument besoin d’une liberté de façon à pouvoir accomplir leur mission sociale. » [1]

Liberté de dissémination

Les résultats de la chaire sont la propriété de l’EPFL. La chaire a la liberté de les publier dans des revues scientifiques.

« Un aspect important de la liberté académique est, comme le signalait Einstein, la dissémination des connaissances:

“Par liberté académique, j’entends le droit de rechercher la vérité et de publier et enseigner ce que l’on tient pour vrai. Ce droit implique également un devoir : on ne doit dissimuler aucune partie de ce que l’on a reconnu comme vrai. Il est évident que toute restriction de la liberté académique sert à restreinte la dissémination du savoir, ce qui entrave le jugement rationnel et l’action.” [2]

En effet, la diffusion des connaissances est une exigence des fonctions professorales. Lorsque cette diffusion se voit restreinte, cela a des répercussions négatives sur la vie scientifique, ce qui justifie la pertinence de la défense de cette liberté. » [1]

Liberté de collaboration

La chaire a la liberté de collaborer avec d’autres institutions ou des sociétés industrielles. Dans ce cas, des contrats de recherches sont mis en place par l’Office de Transfert de Technologies de l’EPFL avec ces partenaires. Ces contrats définissent, selon les principes établis par l’EPFL, les modalités de transfert de la propriété intellectuelle issue spécifiquement de ces mandats, le droit de publication, ainsi que les éventuelles obligations de confidentialité qui s’appliquent aux informations appartenant aux sociétés industrielles.

La société Patek Philippe SA qui a fait un dont pour soutenir la création de cette chaire a la possibilité d’établir de tels contrats de recherche avec cette dernière, au même titre et aux mêmes conditions que toute autre société industrielle.
La société Patek Philippe SA, n’a de droit de regard, ni sur les contrats établis par la chaire avec des tiers, ni sur les résultats de ces recherches.

Références

[1] Rangel, H. (2007). Le principe de liberté académique dans l’ère du conservatisme et de la globalisation », McGill Journal of Education, vol.42 , n°1.

[2] Rendel, M. (1988). Human rights and academic freedom. Tight, M. (Ed.) Adacemic freedom and responsibility. Guilford, England : Open University Press. (traduction française de la citation par S. Henein)

IsoSpring : continuous mechanical time

IsoSpring : film réalisé pour l’exposition Jules Grossmann au Locle par Gasser Media, Mai 2018

Mechanical timekeeping began in the Middle Ages with the invention of the escapement. After the introduction of oscillators in the 17th century, mechanical clocks and watches continued to rely on escapements. Despite numerous technical advances, today’s escapements suffer from reduced mechanical efficiency. The IsoSpring project exploits ideas dating back to Isaac Newton to create a new time base which can be driven continuously, without the stop-and-go “ticking” of traditional mechanical clocks and watches. This solves the escapement problem by completely eliminating it: the mechanical watch can work without an escapement.

The result is a simplified mechanism having greatly increased efficiency and chronometric accuracy. This project is based on a new family of oscillators and maintaining mechanisms patented by the EPFL.

An industrial project was established in 2014 and successfully completed in 2017. This project was extended to a second phase, currently in its second year. This phase is focused on miniaturizing the IsoSpring concept to the watch scale. The key innovation is the use of a novel patented mechanism consisting of four balances whose rotations are converted to linear motion by classical Watt linkages. We named this oscillator Wattwins in order to highlight the historical inspiration of our mechanism. This new oscillator is insensitive to linear accelerations as required for wrist watches. Moreover, it is insensitive to rotational accelerations which is not always the case for classical mechanical watches. We have constructed physical demonstrators and our experimental measurements aim at validating the insensitivity to gravity.

The IsoSpring’s leaflet is available here.

Wattwins oscillator manufactured in silicon.

Wattwins oscillator in silicon at watch scale.

Prototype “Neuchâteloise” clocks with translational oscillator
Prototype “Neuchâteloise” clocks with rotational oscillator
Towards watch scale IsoSpring
IsoSpring team at the Neuchâtel City Hall inauguration

Virtual impulse escapement concept

Instant-Lab introduced virtual impulse escapements in which a double beat escapement becomes a dead beat escapement when the balance wheel is at its operating amplitude. In this way, the advantages of dead beat escapements : direct impulse, greater freedom in choosing impulse position, are preserved, while the disadvantages : sensitivity to shock and difficult self-start, are minimized.

The results of this project were published in the Bulletin de la Société Suisse de Chronométrie, the technical publication of Swiss watchmaking, in 2018.

Self-starting functionality of virtual impulse escapement concept.

Virtual impulse escapement demonstrator.

I. Vardi; R. A. Bitterli; L. Convert; E. Thalmann; S. Henein

Bulletin de la Société Suisse de Chronométrie. 2018.

High quality factor oscillators for wrist watches

Current mechanical wrist watches have an oscillator consisting of a balance wheel mounted on jewelled bearings and a hairspring. The use of flexure bearings instead of traditional pivots leads to a significant increase in quality factor, i.e., reduced energy loss. As a result, power reserve can be significantly increased and chronometric precision can be improved thanks to reduced oscillator perturbation. However, these new oscillators are sensitive to gravity and have isochronism defects. This project explores novel flexure- based pivots minimizing these issues.

A paper based on this research appeared in the Journal of Mechanical Design in 2018.

Comparison of state-of-the-art flexure versus Instant-Lab mechanism
Gravity insensitive flexure pivot (GIFP) demonstrators

Programmable multistable energy storage mechanisms

This project introduces the concept of programmable multistable mechanism in which the number and position of stable states of a multistable mechanism can be modified. A complete qualitative analysis of a generic multistable mechanism, the T-shaped mechanism, was established using analytical tools based on Euler-Bernoulli beam theory. These results were validated numerically using Finite Element Analysis and experimentally using physical models. Applications include new surgical tools and escapements.

Two scientific papers based on this research were published in the Journal of Mechanical Design in 2018 and a further article will appear in 2019 in the Journal of Medical Devices.

T-shaped multistable mechanism programable to have 1 to 4 stable positions
Stable and unstable states of the T-shaped mechanism

Interactive intelligent robotics and 3D printing for surgery and interventional radiology (SPIRITS)

The SPIRITS (Simple Printed Interactive Robotics for Interventional Therapy and Surgery) project involves developing a robotic device for image-guided surgery and interventional radiology with a number of innovations, such as a tactile transducer, an intelligent needle, new 3D printing methods and new actuators and robots.

This Interreg project is a collaboration between several leading institutions: INSA Strasbourg, Hochschule Furtwangen, University Hospital Mannheim, Fachhochschule Nordwestschweiz, EPFL. Instant-Lab is in charge of developing a needle with a flexure based selective stiffness and force sensing at the tool tip to better monitor and control needle placement.

SPIRITS team.

CTI Safe Puncture Optimized Tool (SPOT) for retinal vein cannulation

Retinal Vein Occlusion is a vascular disorder causing severe loss of vision. Retinal vein cannulation and injection of therapeutic agents in the affected vein is a promising treatment but the small size and fragility of retinal veins as well as the surgeon limited hand gesture precision and force perception makes this procedure too delicate for routine operations. The project aims at providing a compliant mechanical tool relying on a new programmable multistable mechanism to safely cannulate veins. This mechanism has the advantage that puncturing stroke and force can be predetermined which makes puncturing independent of surgeon manipulation. The feasibility of this project was demonstrated by a prototype made by femto-laser printing, one of the first buckled mechanisms made in glass. The focus is now on integrating microfluidics in the prototype.

This project is funded by the Commission for Technology and Innovation CTI (Switzerland) with FemtoPrint SA as industrial partner, and run in collaboration with Pr. Th. Wolfensberger, Hôpital Ophtalmique Jules-Gonin, Lausanne.

The results of this research will be published in the Journal of Medical Devices in 2019.

Programmable multistable mechanism for retinal vein cannulation
Glass needle for retinal vein puncturing (left) and its bistable mechanism (right)

Adjustable midsole intervention footwear for patients with medial compartment knee osteoarthritis (ADVANCER, SNSF project)

This project consists of a geometrically adjustable shoe orthotic to balance knee and hip loads which could otherwise lead to cartilage wear and tear, thus avoiding surgical intervention. Our proposed solutions are based on flexible elements combined with stiffness adaptable materials.

This Swiss National Science Foundation project is a collaboration with CHUV (Centre Hospitalier Universitaire Vaudois). Different prototypes were realized. Tests with patients are under CHUV ethical commission evaluation. We are currently examining if the proposed device can be developed into a commercial product. One patent was filed.

Geometrically adjustable shoe orthotic.

Biopsy needle

Biopsy needle equipped with force sensor at its extremity allowing for precise navigation through corporal tissue via force sensing tip.

Biopsy needle tip force sensor

Load cell with tunable stiffness dedicated to force sensing in nanoprobing applications

Contact detection and quantification between a probe and a sample is essential in nanoprobing applications. It is a must in automation and applications where a stable “probe/sample” contact has to be maintained during long lasting measurements. This project focus on a methodology of designing a flexure-based load cell that can be used with a microrobotic platform in nanoprobing applications. The innovative design (patent filed) will be capable of evaluating various ranges of forces depending on the application scale.

Building 4.0

The project Building 4.0 is conducted in collaboration with Granite Apps ltd. The project consists of navigating a building using beacon (Bluetooth low energy emitters) technology coupled with a dedicated application running on cell phone and taking benefit of the “stream” concept. The use case is Microcity building. The goal is to guide visitors to specific locations, to enhance security aspects and augment building content (e.g. display extended poster contend).

CTI Miniature flexure structures for multi-degree of freedom contact force sensing (VIVOFORCE)

The project developed active surgical tools fitting microsurgery requirements, e.g., eye and brain surgery. Combining flexible structure technology provided by Instant-Lab together with Sensoptic SA’s in-house optical fiber based sensing technology which has been successfully used in heart, ear, nose and throat surgery. Providing surgical instruments that are force sensitive at the tool tip allows precise and reliable
surgical gestures far exceeding current practice. Watchmaking applications are also foreseen.

This project was funded by Sensoptic SA and the Commission for Technology and Innovation CTI (Switzerland) and run in collaboration with Pr. Th. Wolfensberger, Hôpital Ophtalmique Jules-Gonin, Lausanne. The project was completed within budget in November 2016 successfully satisfying the goals set by all partners.

Retinal surgery with force sensitive peeling hook

STI Enable SOLE Project

The object of the SOLE project is to produce ADVANCER prototypes and to test them on CHUV patients. The project is funded by the EPFL STI (School of Engineering) Enable Initiative.

Adjustable midsole intervention footwear (orthotic) for patients with medial compartment knee osteoarthritis

Spinal screw placement tool

This Instant-Lab project develops low cost passive alignment tools for spinal pedicle screw placement. The goal is to improve the surgeon’s ability to accurately insert a pedicle screw following a predetermined trajectory. This reduces the risk of plunging which can damage soft tissue, nerves, or the spinal cord.

Flexure based level indicating tilt angle for pedicle screw placement