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Composition
Decomposition
Engine
Setup

Flex Parameters from values

Set environmental parameters for your simulation. Specify them here.

Inputs

NameIDDescriptionType
GravityGravityConstant acceleration vector applied to all particles.Vector
RadiusRadiusThe maximum interaction radius for particles.Number
Solid Rest DistanceSolidRestDistanceThe distance non-fluid particles attempt to maintain from each other, must be in the range (0,.Number
Fluid Rest DistanceFluidRestDistanceThe distance fluid particles are spaced at the rest density, must be in the range (0, radius], for fluids this should generally be 50-70% of Radius, for rigids this can simply be the same as the particle radius.Number
Collision DistanceCollisionDistanceDistance particles maintain against shapes, note that for robust collision against triangle meshes this distance should be greater than zero.Number
Particle Collision MarginParticleCollisionMarginIncreases the radius used during neighbor finding, this is useful if particles are expected to move significantly during a single step to ensure contacts aren't missed on subsequent iterations.Number
Shape Collision MarginShapeCollisionMarginIncreases the radius used during contact finding against kinematic shapes.Number
Max SpeedMaxSpeed The magnitude of particle velocity will be clamped to this value at the end of each step.Number
Max AccelerationMaxAccelerationThe magnitude of particle acceleration will be clamped to this value at the end of each step (limits max velocity change per-second), useful to avoid popping due to large interpenetrations.Number
Dynamic FrictionDynamicFrictionCoefficient of friction used when colliding against shapes.Number
Static FrictionStaticFrictionCoefficient of static friction used when colliding against shapes.Number
Particle FrictionParticleFrictionCoefficient of friction used when colliding particles.Number
RestitutionRestitutionCoefficient of restitution used when colliding against shapes, particle collisions are always inelastic.Number
AdhesionAdhesionControls how strongly particles stick to surfaces they hit, default 0.0, range [0.0, +inf].Number
Sleep ThresholdSleepThresholdParticles with a velocity magnitude < this threshold will be considered fixed.Number
Shock PropagationShockPropagationArtificially decrease the mass of particles based on height from a fixed reference point, this makes stacks and piles converge faster.Number
DissipationDissipation Damps particle velocity based on how many particle contacts it has.Number
DampingDampingViscous drag force, applies a force proportional, and opposite to the particle velocity.Number
FluidFluidIf true then particles with group index 0 are considered fluid particles and interact using the position based fluids method.Boolean
ViscosityViscositySmoothes particle velocities using XSPH viscosity.Number
CohesionCohesionControl how strongly particles hold each other together, default: 0.025, range [0.0, +inf].Number
Surface TensionSurfaceTensionControls how strongly particles attempt to minimize surface area, default: 0.0, range: [0.0, +inf].Number
Solid PressureSolidPressureAdd pressure from solid surfaces to particles.Number
Free Surface DragFreeSurfaceDragDrag force applied to boundary fluid particles.Number
BuoyancyBuoyancyGravity is scaled by this value for fluid particles.Number
Plastic ThresholdPlasticThresholdParticles belonging to rigid shapes that move with a position delta magnitude > threshold will be permanently deformed in the rest pose.Number
Plastic CreepPlasticCreepControls the rate at which particles in the rest pose are deformed for particles passing the deformation threshold.Number
WindWindConstant acceleration applied to particles that belong to cloth and inflatables, drag needs to be > 0 for wind to affect triangles.Vector
DragDragDrag force applied to particles belonging to cloth and inflatables, proportional to velocity^2*area in the negative velocity direction.Number
LiftLiftLift force applied to particles belonging to cloth and inflatables, proportional to velocity^2*area in the direction perpendicular to velocity and (if possible), parallel to the plane normal.Number
Relaxation ModeRelaxation ModeHow the relaxation is applied inside the solver. If false, the relaxation factor is a fixed multiplier on each constraint's position delta. If true, the relaxation factor is a fixed multiplier on each constraint's delta divided by the particle's constraint count, convergence will be slower but more reliable.Boolean
Relaxation FactorRelaxationFactorControl the convergence rate of the parallel solver, default: 1, values greater than 1 may lead to instability.Number

Outputs

NameIDDescriptionType
FlexParamsParamsFlexParams object to be passed into the engine.Generic Data

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