Surgery simulation platform is a combination of three components; deformable model; input output method and; collision detection method. Throughout the literature there are number of techniques, algorithms and mechanisms have been proposed to enhance the performances of those modules. In this paper we presents an extensive literature review on deformable object modeling algorithms, collision detection methods, haptic devices, haptic force feedback and rendering mechanism.   Stiffness value is the governing parameter which decides the overall performance as well as the realism of the deformable models. With the stiffness it can increase or decrease the flexibility of the model. With the haptic force feedback it can sense the flexibility of the model. Hence it is important to impose an acceptable stiffness on model to enhance the user realism. Based on the methods which have been used to implement the deformable model, the acceptable stiffness value range may vary. In this paper it has discussed the stiffness parameter extraction process for the designed deformable gallbladder model under certain constraints and also has proposed an acceptable stiffness value range. The process has been evaluated based on the young modulus value of the live gallbladder tissue.
['Aruni Nisansala', 'Gustavo Angelo Dias', 'N. D. Kodikara', 'Maheshya Weerasinghe', 'Damitha Sandaruwan', 'Chamath Keppitiyagama', 'Nuwan Dammika']
Stiffness parameter evaluation for graphical and haptic gallbladder model