Conception et modélisation modulaire d'un robot bio-inspiré extensible pour l'accès aux tumeurs dans le cerveau

Abstract

The aim of this work, which was part of a research programme to develop a minimally invasive multirobotic neurosurgery system for cerebral tumour ablation, was the design and modelling of a robot that can be deployed inside the brain, along curved trajectories, with no free space surrounding its structure nor any natural guide to help its progression. After definition of the deployment task, a state of the art search found a wide range of systems, from which a bio-inspired continuum design based on the elephant's trunk was selected. The modular robot approach was defined and geometrically modelled by combining a cinematic chain with the continuum mobility of the robot. A deployment strategy, based on an ordered succession of local extensions/retractions for an iterative elongation of the robot, was formalised for the generic case of N modules, then validated with plans of simulations of robots composed of 1 to 3 modules (trajectory following error less than 1 mm). The agar gel (whose texture is close to that of the brain) study model was used to estimate the penetration efforts of the robot in the brain, and CAD to construct a demonstrator robot on springs. A human/machine interface was programmed to simulate and control the robot, and tests were conducted to validate certain aspects of the deployment. A second, pneumatically actuated, demonstrator will be constructed to carry out a comparative study of the two prototypes. While there is room for improvement in some areas, the preliminary results are encouraging. Collaborative works with specialists from different fields should make it possible to optimize the deployment robot.