Research On Virtual Surgery Cutting Technique Based On Force Feedback

Virtual surgery is a perfect combination of virtual reality technology and modernmedical field, and virtual surgery simulation system is a virtual reality application syetem totrain new surgeons before surgery by providing realistic virtual surgery scene in the visual andtactile, it can also be applied to the fields such as predicting surgical results, surgicalnavigation, etc. The virtual surgery simulation system can not only save expenses and time fortraining new surgeons, but also reduce the risk of the surgical procedure.Soft tissue organs cutting operation is an important and difficult part of virtual surgerysimulation system. Cutting simulation of system should be able to do with the good real-timeinteraction and stability, at the same time it should give the operator realistic immersiveexperience in the visual and tactile, incision smoothness and force feedback in other words.For the problems often existed in human soft tissue body model cuuting researches,such as non-smooth cutting incision and low real-timing, this paper proposed a new cuttingalgorithm based on Bezier surfaces, designed and implemented a cutting simulation system ofa soft tissue model based on force feedback. And then an innovative way to increase thedeformation and recovery function of the soft tissue around the incision was achieved in thecutting process, made the cutting result more realistic.Firstly, based on typical elements of a force feedback virtual surgery cutting system, theoverall structure of the system, program design framework, hardware and softwarecomponents, structure of system framework and software modules are designed for theimplemented system.Secondly, the visual rendering tool OpenGL was used to establish a virtual virtual humanskin soft tissue model in the geometric modeling aspect, Mass-spring/damper model was usedto be as the calculation model in the soft cutting and deformation and haptic interactionprocess in the physical modeling aspect.Thirdly, in the cutting algorithm applied to the surface model based on Bezier curvesbackground, a new body model cutting algorithm based on Bezier surfaces was proposed inthis paper. In the visual, it achieved an ideal cutting in the surface incision and hollowcross-section to the inside.Finally, PHANToM Omni haptic interaction device was used to achieve the interactionof virtual scalpel and body’s soft tissue in the cutting process. The frictional force of thetangential direction was increased in the cutting simulation process, and the force of the spring and friction which feedbacked to the operator made the force feedback more realistic.The experiment results showed that the cutting algorithm based on Bezier surfacessolved the equilibrium problems between incision smooth and real-time. The implementationof this cutting algorithm under the force feedback met the visual and tactile dualrequirementsof the virtual surgery.