Archive for February, 2011

Regular and adaptive signed distance fields

Instead of relying on explicit definitions (e.g. of collision geometry), the framework makes extensive use of implicit surface descriptions. This data tells much more about an object in space and allows for a substantial set of features including very efficient collision detection and response, normal and volume retrieval, level sets (for boundary particles, lego brick […]

Rigid Body Particles

Friction and attraction forces can only produce granular effects up to a certain limit. To simulate piling and other interesting stacking effects, spherical particles need to be replaced by more complex structures and shapes. Particles hence need to become rigid bodies. In the provided video each particle becomes the centre of mass of a pyramidal […]

Inextensible Cloth

Instead of applying forces based on springs, stiff connections are introduced to account for attributes of inextensible cloth. The constrained structure is relaxed in an iterative manner to converge to an optimal solution. Bend and shear connections can optionally be weighted to allow for different material behaviours. Virtual particles are placed on the centre of […]

Heat Diffusion and Viscosity Adaption

Temperature (colour coded on the left) is diffused using the SPH approach. Per particle user defined conductivity values allow for a controlled melting process while an ambient temperature and conductivity is cooling the particles down. The viscosity of the particles is directly influenced by the temperature. Hotter particles receive a lower viscosity, i.e. they flow […]

Predictive Corrective Incompressible SPH

Implementation of the PCI SPH algorithm from B. Solenthaler et al. (vmml.ifi.uzh.ch/​files/​pdf/​publications/​pcisph.pdf).
An explicit foam handling allows for the generation of foam based on velocity or vorticity. Fluid particles are transformed into foam particles with user defined distinct rest density and viscosity. This makes it possible to have water interact with foam particles. To restrict the […]

Viscous fluids

Honey like fluids using a combination of springs and SPH, integrated using a predictor corrector scheme, to allow for high viscosity and high surface tension. SDF based collision detection and response with an additionally applied boundary force to simulate stickiness.

Elastic, plastic and tearable materials

Viscous, plastic, elastic and tearable materials are modelled using various kinds of springs, and iterative approaches to allow for stable high viscosity and surface tension. The spring types include simple force based or stiff springs initialised at start time, dynamic springs which are created at simulation time (between close by particles), springs with adjustable rest […]

DEM Particles with SDF collision

DEM particle simulation using a predictor corrector scheme.
Inter-particle collision detection is accelerated using a uniform hash grid. Signed distance field based object collision detection and response. Surface normals (for particle placement and friction effects) are interpolated from the distance gradient of the field. Features damping, shearing as well as dynamic and coloumb friction effects.




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