Soft Tissue Deformation Modeling And Force Feedback Algorithm For Virtual Acupuncture Surgery

With the development of virtual reality technology,its application in medical field is becoming more and more extensive.Virtual reality uses computer graphics to construct a virtual soft tissue deformation model,and the interaction with the virtual model is added to make it feel.The simulation system provides a real representation of the operator in vision and touch,which makes the operator have a strong sense of presence and immersion.Because of the introduction of the tactile feedback,when needing surgery training,the doctor can through visual observation of deformation of soft tissue at the same time,also can feel the strength of a needle,like the feeling of real operation,such a virtual training system can be greatly for the training level of the doctor,especially for needing surgery that requires a lot of training to master the skills.On the premise of ensuring the real time and accuracy of deformation simulation,and based on the mechanical properties of real human skin soft tissue,the mass-spring model based on surface model was selected.For the virtual soft tissue model to functioning in the process of interaction of information,in the original surface model increased the dummy spring,make the virtual soft tissue deformation can be more real and vivid,and in doing so,to meet the requirements of the interaction system of stability.In the field of model kinematics,the method of real time and other numerical integration method is selected as the model deformation algorithm in this paper.The real-time deformation and force feedback algorithm of soft tissue in this paper is based on the spring-damper.The total shape variables of the soft tissue deformation process are represented by the virtual spring deformation,and the feedback force is the resultant force of the virtual spring deformation of the stressed particle.Based on this model,the real time of the deformation algorithm can meet the requirements of virtual interaction-interactive systems require the ability to provide visual and tactile information when interacting with each other.In order to ensure authenticity,the two must be kept in sync so as to give the operator a sense of immersion and presence.In this paper,OpenGL 3D graphics library is used to render the soft tissue model,and provide visual information through the display.Using the OpenHaptics software package to make the rendering of the virtual soft tissue,the Phantom Desktop was used to needle the virtual soft tissue.Finally,the simulation results show that the system can satisfy the real-time performance of the operation under certain precision.