Virtual Tissue Cutting
Virtual surgery demands fast and real time simulations. Finite element analysis can be used for cutting simulation; however, finite element analysis is computationally intensive and is unsuitable for real time applications involving cutting of a large amount of tissue.
We have developed a virtual tissue cutting simulation with haptic feedback in real time. The haptics feedback has been implemented using fuzzy logic and Kelvin model, rendered in real time. Unlike FEM based techniques and others for simulating tissue cutting, the computation complexity has been reduced very much.
The tissue material experimental data are from several litreture and the rupturing force is calculated from the fuzzy model for the particular depth and velocity of the scalpel from. Kelvin model force is used for haptic response function based on the time and displacement and the fuzzy model is used for the haptic response function based on the depth and velocity of the scalpel. Thus making the simulation based on time, displacement, velocity, and depth of the scalpel.
The figure above shows the recorded 3D data from the virtual tissue cutting. The recording is for the a depth of cutting, while other three parameters viz. velocity and displacement are varied and the force experience by the used has been recorded.
The computational requirement has been simplified to reduce the computing time as the haptics system has to be refreshed at 1000Hz. The graphics part is done using video based rendering where the frames from real surgery video can used to give the realistic effect of the simulation.
The haptic response is calculated using Kelvin model for soft tissue and the force at which the soft tissue ruptures is based on fuzzy model. Care is taken to make the simulator as realistic as possible and also to make it as simple as possible so that the users (doctors) will train themselves in a better and easy way.
|Last Updated: May 26, 2008 4:45 PM||Comments: Manivannan M|