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P Tanguy

Publications and source records attributed to P Tanguy.

2 recordsLinked to original sources

Bimanual haptic workstation for laparoscopic surgery simulation.

Realistic laparoscopic surgical simulators will require real-time graphic imaging and tactile feedback. Our research objective is to develop a cost-effective haptic workstation for the simulation of laparoscopic procedures for training and treatment planning. The physical station consists of a custom-built frame into which laparoscopic trocars and surgical tools may be attached/inserted and which are continuously adjustable to various positions and orientations to simulate multiple laparoscopic surgical approaches. Instruments inserted through the trocars are attached to end effectors of two haptic devices and interfaced to a high speed PC with fast graphics capability. The haptic device transduces 3D motion of the two manually operated surgical instruments into slave maneuvers in virtual space. The slave instrument tips probe the simulated organ. Simulations currently in progress include: 1) Surface-only renderings, deformation, and haptic interactions with elements in the gall gladder surgical field; 2) Voxel-based simulations of the bulk manipulation of tissue; 3) laparoscopic herniorrhaphy. This system provides force feed-forward from the grasped tools to the contact tissue in virtual space, with deformation of the tissue by the virtual probe, and force feedback from the deformed tissue to the operator's hands.

Computer Graphics↗

Toward a non-traumatic determination of the rheological properties of the vascular wall.

It is possible to show the existence of a biunivocal relationship, at a given time, between the longitudinal velocity profile of a pulsatile flow in a flexible tube on the one hand and the pressure gradient which induces the flow and the mechanical behavior of the wall on the other hand, for an assumed rheological model. From experimental data of velocity profiles, only pressure gradients can be correctly calculated. To determine the elasticity of the material, a theory is developed which requires a knowledge of the time dependence of the wall motion. This theory is tested first on numerically simulated velocity data then verified experimentally with a hydromechanical device.

Animals↗