Date of Award

2009

Document Type

Master Thesis

Degree Name

Master of Engineering (Research)

Department

Department of Electronic Engineering

First Advisor

Dr. Joe Connell

Abstract

A virtual training environment for temporal bone surgery incorporating haptic, visual and audio feedback is presented in this work. Data are derived from Computed Tomography (CT) scans, thus patient-specific cases may be examined in the simulator.

Two main classes of volume haptic algorithm exist for virtual surgery, namely proxy-based and non proxy-based. A review of the evolution of relevant haptic algorithms is presented. Proxy-based and non proxy-based algorithms are implemented and their performance measured against each other by comparison with real-world force data. An improved proxy-based feedback algorithm is also presented. This algorithm uses a spherical proxy which prevents the virtual drill burr from passing through gaps in a volume smaller than its own size. Proxy position is automatically adjusted to prevent immersion within the volume. A new method of force calculation is used which results in improved force accuracy.

A volume ray-casting method is employed for visual feedback. Vertex and fragment programs are written which execute on the Graphics Processing Unit (GPU), thus utilizing the parallel processing capabilities of modern GPUs. Colour transfer functions may be updated on-the-fly while the simulation is running, thus emphasis may be placed on various anatomical structures by adjusting opacities and colours.

Access Level

info:eu-repo/semantics/openAccess

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