Thibault Gouache (cofounder of Cornis), did his PhD for ESA (European Space Agency), in collaboration with ISAE (Toulouse, France) and the University of Surrey (Guilford, UK) in the field of automatic and mechanics. A strong expertise in design, assessment, evaluation and testing of space mechanisms was acquired.

These_forage_thibault

Client problem

On the moon or Mars to search for traces of life, it is mandatory to dig or drill beneath the surface. Any drilling system needs an important force applied on it to penetrate; On the Moon and Mars there is little gravity and the mass of space systems is limited. It is thus very difficult if not impossible to push on classical space drilling systems. New drilling solutions re thus necessary.

Solution proposed

Novel mechanisms for lunar and Martian regolith penetration, exploration and sampling were designed, prototypes and tested. Thanks to the observation of nature (an insect drilling into wood to lay its eggs), a team of researchers funded by ESA (European Space Agency) designed a drilling system based on the alternative and reciprocating translation of 2 valves. The alternating movement enables a significant reduction of the normal force that must be applied by the carrier on the drill head.

A first prototype was developed for regolith type substrates (sandy soils). To conduct performance tests, it was necessary to define a standardised protocol to test drilling systems in regolith substrates. Thanks to this protocol, objective comparisons between different drilling systems performance in regolith is made possible. The influence of relative density of the regolith that is being penetrated is controlled and reported.

To confirm the experimental conclusions of this work, numerical simulations using DEM (discrete element methods) and a highly parallelized code compatible with GPU were used. The experimental and numerical data enabled to conclude that the studied drilling system is able to penetrate efficiently into regolith with very little over-head normal force mainly because the drill head-shape causes a lateral deflection during the reciprocating translations.

Other missions

  • PhD

Our R&D project manager, Ahmed Jhinaoui, did his PhD at INRIA (French Institute for Research in Computer Science and Control). The subject of his work is part of a wider research thematic in the context of a collaboration between INRIA and ISAE (French Aerospace Institute), via the project I4S which is about structural health monitoring for the purpose of reducing maintenance interventions.

Our CTO, Baptiste Coulange, did his PhD for CNES (the French Space Agency) and University of Paris Descartes on detecting of aliasing in satellite images.

Earth observation satellites are optimised to obtain the best image quality. The size of the sensors and the parameters of the optical chain are designed to obtain the best compromise between image resolution and acquisition artefacts. The higher the resolution the more artefacts are present.

Aliasing which is one of the artefacts in satellite images can lead to image misinterpretation. It is thus critical to detect it. By using the duality between spatial localisation in the image and aliasing relationships in the Fourier transform plane, it was possible to develop and validate a aliasing detection algorithm.

Our research project manager, Virginie Delavaud, carried out her PhD thesis for SNCF, the french railway company, with ENSTA ParisTech, about railway rolling noise.

Rolling noise is the main source of railway transportation noise for a wide speed range (between 50 and 320 km/h). Rolling noise occurs when a wheel moves on a rail in a straight line. On the same scope, the impact noise is due to discrete irregularities on either of the two structures, such as rail joints or wheelflats.