| Summary: | This work presents a methodology for haptic rendering of fluid filled structures that are enclosed in
linear elastic media using the Finite Element Method.
Haptic medical simulation is a growing field of research motivated by creating risk-free virtual environments
for medical students to learn and practise surgical procedures. One of the challenges in creating
medical simulators is modeling the deformation of living tissues. Due to minimum haptic update rate
requirements, the deformable methods are simplified and precomputed. Most medical simulators model
anatomy as elastic material with constant or varying stiffness. However, human anatomy includes a variety
of fluid filled structures. To improve the realism of these simulators, fluid filled bodies should be modeled
in addition to elastic media.
This thesis presents a method for simulating fluid effects by adding hydrostatic fluid pressure to a body
of elastic material modeled with the Finite Element Method. By distributing fluid pressure across an interior
cavity surface, the fluid can be modeled using a force boundary condition. Proportional feedback is used to
solve for an incompressible fluid relationship between the cavity pressure and volume. Linear finite elements
are used so the stiffness matrix can be condensed to achieve real-time haptic rates.
To validate that this method predicts deformation of a fluid filled cavity in a realistic manner, the deformation
a fluid filled phantom is tracked and compared to a Finite Element simulation of the same phantom.
The data is found to agree well with the simulation.
A real-time haptic simulation of elastic media enclosing incompressible fluid, based on an existing 2D
needle insertion simulation, is presented. Numerical tests show that simulation of a relatively large 3D fluid
body will be possible at haptic rates. === Applied Science, Faculty of === Electrical and Computer Engineering, Department of === Graduate
|
|---|
