In order to solve the problem of real-time soft tissue torsion simulation in virtual surgeries,a torsion model based on coil spring is proposed to actualize real-time interactions and applications in virtual surgeries...In order to solve the problem of real-time soft tissue torsion simulation in virtual surgeries,a torsion model based on coil spring is proposed to actualize real-time interactions and applications in virtual surgeries. The proposed model is composed of several connected coil springs in series. The sum of torsion deformation on every coil is equivalent to the soft tissue surface deformation. The calculation of the model is simple because the method for calculating the torsion deformation for each coil spring is the same. The virtual surgery simulation system is established on PHANTOM OMNI haptic device based on the Open GL 3 D graphic interface and VC + + software,and it is used to simulate the torsion deformation of virtual legs and arms. Experimental results show that the proposed model can effectively simulate the torsion deformation of soft tissue while being of real-time performance and simplicity,which can well meet requirements of virtual operation simulations.展开更多
Most implantation cases are implemented using implants selected from the available standard set, but in some cases, only those implants conforming to individual patient's skeletal morphology can serve the purpose....Most implantation cases are implemented using implants selected from the available standard set, but in some cases, only those implants conforming to individual patient's skeletal morphology can serve the purpose. This paper proposes a new approach to design and fabricate custom-made exact-fit medical implants. With a real surgical case as the example,technical design details are presented; and three algorithms are given respectively for segmentation based on object features, triangular mesh defragmentation and mesh cutting.展开更多
A method for simulation of cutting virtual soft tissue objects made of tetrahedron elements is developed. A linear isotropic elastic model is used for the soft tissue material properties and a tensor-mass model chosen...A method for simulation of cutting virtual soft tissue objects made of tetrahedron elements is developed. A linear isotropic elastic model is used for the soft tissue material properties and a tensor-mass model chosen for the physical deformation. The Verlet leapfrog method is used to perform time integration in solving the dynamic equations. Cutting is simulated by simply removing the tetrahedron elements that are intersected with the virtual scalpel. By making use of the spatial coherence, collision detection between soft tissue objects and the virtual scalpel is sped up. To facilitate the simulation, the soft tissue object is represented by linked lists of vertices, edges and tetra elements with pointers to the related neighboring features. The established software framework can serve as a base for the future development. Results of virtual experiments are shown and discussed. Possible future directions are also given.展开更多
The paper proposes a novel desktop virtual surgical simulation system capable of not only surgical training but also operative planning, surgery rehearsal and telesurgery, which is mainly used on the robot-assisted or...The paper proposes a novel desktop virtual surgical simulation system capable of not only surgical training but also operative planning, surgery rehearsal and telesurgery, which is mainly used on the robot-assisted orthopedic surgery system, HIT-RAOS. The paper first introduces the hardware system: HIT-RAOS. Then presents several major characters of the virtual system: developing tools, building schemes and collision detection algorithm. Additionally, virtual reality based telesurgery is implemented. Based on these works, experiments of locking of intramedullary nails are conducted, and results are content.展开更多
基金Supported by the National Natural Science Foundation of China(No.61502240,61502096,61304205,61773219)the Natural Science Foundation of Jiangsu Province(No.BK20141002,BK20150634)
文摘In order to solve the problem of real-time soft tissue torsion simulation in virtual surgeries,a torsion model based on coil spring is proposed to actualize real-time interactions and applications in virtual surgeries. The proposed model is composed of several connected coil springs in series. The sum of torsion deformation on every coil is equivalent to the soft tissue surface deformation. The calculation of the model is simple because the method for calculating the torsion deformation for each coil spring is the same. The virtual surgery simulation system is established on PHANTOM OMNI haptic device based on the Open GL 3 D graphic interface and VC + + software,and it is used to simulate the torsion deformation of virtual legs and arms. Experimental results show that the proposed model can effectively simulate the torsion deformation of soft tissue while being of real-time performance and simplicity,which can well meet requirements of virtual operation simulations.
文摘Most implantation cases are implemented using implants selected from the available standard set, but in some cases, only those implants conforming to individual patient's skeletal morphology can serve the purpose. This paper proposes a new approach to design and fabricate custom-made exact-fit medical implants. With a real surgical case as the example,technical design details are presented; and three algorithms are given respectively for segmentation based on object features, triangular mesh defragmentation and mesh cutting.
文摘A method for simulation of cutting virtual soft tissue objects made of tetrahedron elements is developed. A linear isotropic elastic model is used for the soft tissue material properties and a tensor-mass model chosen for the physical deformation. The Verlet leapfrog method is used to perform time integration in solving the dynamic equations. Cutting is simulated by simply removing the tetrahedron elements that are intersected with the virtual scalpel. By making use of the spatial coherence, collision detection between soft tissue objects and the virtual scalpel is sped up. To facilitate the simulation, the soft tissue object is represented by linked lists of vertices, edges and tetra elements with pointers to the related neighboring features. The established software framework can serve as a base for the future development. Results of virtual experiments are shown and discussed. Possible future directions are also given.
文摘The paper proposes a novel desktop virtual surgical simulation system capable of not only surgical training but also operative planning, surgery rehearsal and telesurgery, which is mainly used on the robot-assisted orthopedic surgery system, HIT-RAOS. The paper first introduces the hardware system: HIT-RAOS. Then presents several major characters of the virtual system: developing tools, building schemes and collision detection algorithm. Additionally, virtual reality based telesurgery is implemented. Based on these works, experiments of locking of intramedullary nails are conducted, and results are content.