33 results about "Mass spring model" patented technology

The invention relates to the technical field of node positioning in wireless sensor networks, in particular to an anchor-free positioning method based on hop quantification and a mass-spring model. According to the positioning method, a coordinate system with a smaller error is built by the aid of a hop quantification method. Measured distance information is sufficiently used for quantizing the communication radius lengths of sensing nodes into a plurality of hops. The invention further provides an AMSO (adaptive mass-spring optimization) method based on the mass-spring model. The positions of a center node and all neighbor nodes are adjusted by the aid of the AMSO method, the positions of the sensing nodes are optimized by AMSO, and sensing node coordinates are prevented from local optimum in iterative optimization. The positioning method has the advantages of high positioning accuracy, robustness and convergence speed.

The invention relates to a system for dynamically simulating cloth tearing. The system establishes a cloth model by utilizing a mass spring model, so that cloth is decomposed into multiple triangular patches; then, cloth tearing is completed; a Half-edge data structure is added while modelling is carried out; related information of the position of a cloth vertex, the relationship between an edge and a vertex, the relationship among the length of the edge, a surface and the vertex and the adjacency relationship of the surfaces is stored; a bounding box distance field based on the Euclidean distance is created, and used for completing collision detection; the cloth tearing simulation efficiency is increased; a steel body model is created; the gravitational acceleration is added to a rigid body or the cloth, so that the rigid body and the clock are collided; and then, tearing is generated. The system disclosed by the invention can be widely applicable to dynamic analogue simulation of the cloth in design and manufacture and film and television entertainment.

The invention provides a non-stretch cloth simulation oriented mass-spring model constraint method. By adopting the method, deformation repair of a structural spring in a mass-spring model can be realized by correcting the mass point position of the mass-spring model. The mass-spring model constraint method specifically comprises the following steps: in order to accelerate the convergence speed of constraint implementation, giving an optimal relaxation factor based on a topological structure and deformation of the structural spring and the like in the mass-spring model; according to deformation of a single structural spring, calculating components of position correction quantity of mass points at two endpoints along the spring direction; superposing the components of the position correction quantity of the same mass point; multiplying the superposition sum by the optimal relaxation factor, and taking the result as the position correction quantity of the mass point; and finally updating the mass point position so as to realize deformation repair of the structural spring. The mass-spring model constraint method has the beneficial effects that conservation between linear momentum andangular momentum of cloth can be ensured and the non-stretch cloth can be efficiently and stably simulated during the constraint implementation process, thus the method can be widely applied to non-stretch cloth simulation in virtual reality systems for film and video production, digital entertainment and other purposes.

The invention relates to the technical field of node positioning in wireless sensor networks, in particular to a three-dimensional weighted centroid positioning method based on a mass-spring model. The positioning method includes the steps: in an initial phase, amending a weight of the three-dimensional weighted centroid positioning method, and estimating the initial positions of unknown nodes by the weighted centroid positioning method with the amended weight; in an optimizing phase, amending the measuring distance by the aid of error factors, adjusting the unknown nodes to the best positions by the method of the mass-spring model. The positioning method is applicable to positioning geometric peripheral nodes comprising anchor nodes and has the advantages of high positioning accuracy and strong robustness.

The invention discloses a force haptic generation method of flexible texture image based on a mass-spring model. The method comprises the steps of grouping the flexible texture image by areas and acquiring pixel point height value to reconstruct and convert into a three-dimensional texture pattern; creating a deformation surface based on the mass-spring model; reconstructing the three-dimensional texture pattern; mapping the three-dimensional dimension texture pattern to the deformation surface; operating a force haptic interaction device to perform human-computer interaction to drive mass of a triangular grid on the deformation surface to move so as to obtain a triangular patch that an interaction contact of the force haptic interaction device is in impact with the texture pattern; solving to obtain the force haptics and the deformation of the deformation surface. According to the method, the deformation of the flexible texture image and realistic force haptics can be generated, so that the deformation of the flexible texture pattern can be achieved and the realistic force haptics can be generated; people can view the reasonable deformation of the flexible texture image and can also touch to feel the force haptic property of the flexible texture image; the limit of the traditional method that people cannot sense the flexible texture image can be broken.

The invention discloses a soft tissue modeling method based on position constraints and nonlinear springs. (3) Estimate the approximate position of each node, and then judge whether the state of the node constraint equation changes, including the spring length and curvature constraints; if the initial state of the equation changes, the node will be corrected to the correct position within a reasonable range ; If the initial state of the equation does not change, the nonlinear spring and virtual body spring will simulate the deformation effect of the soft tissue; (4) The single-step iteration of calculating the deformation ends, and the next cycle is entered. The present invention adopts a nonlinear spring system and a virtual body spring to simulate the biomechanical properties of soft tissues, and also adopts a new constraint equation to limit the node displacement to enhance the stability of the model, and improves the traditional mass spring model with poor accuracy and instability. defect.