Guillaume Michel

Haribhau Durgesh, Guillaume Michel, Shivesh Kumar et al.

The optimization of parallel kinematic manipulators (PKM) involve several constraints that are difficult to formalize, thus making optimal synthesis problem highly challenging. The presence of passive joint limits as well as the singularities and self-collisions lead to a complicated relation between the input and output parameters. In this article, a novel optimization methodology is proposed by combining a local search, Nelder-Mead algorithm, with global search methodologies such as low discrepancy distribution for faster and more efficient exploration of the optimization space. The effect of the dimension of the optimization problem and the different constraints are discussed to highlight the complexities of closed-loop kinematic chain optimization. The work also presents the approaches used to consider constraints for passive joint boundaries as well as singularities to avoid internal collisions in such mechanisms. The proposed algorithm can also optimize the length of the prismatic actuators and the constraints can be added in modular fashion, allowing to understand the impact of given criteria on the final result. The application of the presented approach is used to optimize two PKMs of different degrees of freedom.

Guillaume Michel, Durgesh Salunkhe, Philippe Bordure et al.

In otolaryngologic surgery, more and more robots are being studied to meet the clinical needs of operating rooms. However, to help design and optimize these robots, the workspace must be precisely defined taking into account patient variability. The aim of this work is to define a geometric atlas of the middle ear and paranasal sinuses for endoscopic robotic applications. Scans of several patients of different ages and sexes were used to determine the average size of these workspaces, which are linked by the similar use of endoscopes in surgery.

Guillaume Michel, Durgesh Haribhau Salunkhe, Philippe Bordure et al.

In otolaryngologic surgery, endoscopy is increasingly used to provide a better view of hard-to-reach areas and to promote minimally invasive surgery. However, the need to manipulate the endoscope limits the surgeon's ability to operate with only one instrument at a time. Currently, several robotic systems are being developed, demonstrating the value of robotic assistance in microsurgery. The aim of this literature review is to present and classify current robotic systems that are used for otological and endonasal applications. For these solutions, an analysis of the functionalities in relation to the surgeon's needs will be carried out in order to produce a set of specifications for the creation of new robots.

Guillaume Michel, Durgesh Salunkhe, Damien Chablat et al.

Since the insertion area in the middle ear or in the sinus cavity is very narrow, the mobility of the endoscope is reduced to a rotation around a virtual point and a translation for the insertion of the camera. This article first presents the anatomy of these regions obtained from 3D scanning and then a mechanism based on the architecture of the agile eye coupled to a double parallelogram to create an RCM. This mechanism coupled with a positioning mechanism is used to handle an endoscope. This tool is used in parallel to the surgeon to allow him to have better rendering of the medium ear than the use of Binocular scope. The mechanism offers a wide working space without singularity whose borders are fixed by joint limits. This feature allows ergonomic positioning of the patient's head on the bed as well as for the surgeon and allows other applications such as sinus surgery.

G. Michel, D. Chablat, P. Bordure et al.

Otologic surgery has some specificities compared to others surgeries. The anatomic working space is small, with various anatomical structures to preserve, like ossicles or facial nerve. This requires the use of microscope or endoscope. The microscope let the surgeon use both hands, but allows only direct vision. The endoscope leaves only one hand to the surgeon to use his tools, but provides a "fish-eye" vision. The rise of endoscopy these past few years has led to the development of numerous devices for the surgeon: the Robotol, first otological robot designed to performed some movements and hold an endoscope, or the Endofix Exo. Both devices need the hand of the surgeon to be moved. No robotic device allows the endoscope to be directed autonomously while the surgeon keeps both hands free to work, just like when he is working with a microscope. The objective of our work is to define the specific needs of the otological assistance surgery.