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add damping energy in line search

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This commit is contained in:
Xuchen Han
2019-09-17 14:58:16 -07:00
parent 3dcfcda19a
commit ae42cc561e
15 changed files with 128 additions and 74 deletions
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39
src/BulletSoftBody/btDeformableNeoHookeanForce.h
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@@ -26,12 +26,12 @@ public:
btScalar m_mu_damp, m_lambda_damp;
btDeformableNeoHookeanForce(): m_mu(1), m_lambda(1)
{
btScalar damping = 0.005;
btScalar damping = 0.05;
m_mu_damp = damping * m_mu;
m_lambda_damp = damping * m_lambda;
}
btDeformableNeoHookeanForce(btScalar mu, btScalar lambda, btScalar damping = 0): m_mu(mu), m_lambda(lambda)
btDeformableNeoHookeanForce(btScalar mu, btScalar lambda, btScalar damping = 0.05): m_mu(mu), m_lambda(lambda)
{
m_mu_damp = damping * m_mu;
m_lambda_damp = damping * m_lambda;
@@ -71,7 +71,7 @@ public:
size_t id3 = node3->index;
btMatrix3x3 dF = DsFromVelocity(node0, node1, node2, node3) * tetra.m_Dm_inverse;
btMatrix3x3 dP;
firstPiolaDampingDifferential(psb->m_tetraScratches[j], dF, dP);
firstPiolaDampingDifferential(psb->m_tetraScratchesTn[j], dF, dP);
btVector3 df_on_node0 = dP * (tetra.m_Dm_inverse.transpose()*grad_N_hat_1st_col);
btMatrix3x3 df_on_node123 = dP * tetra.m_Dm_inverse.transpose();
@@ -85,7 +85,7 @@ public:
}
}
virtual double totalElasticEnergy()
virtual double totalElasticEnergy(btScalar dt)
{
double energy = 0;
for (int i = 0; i < m_softBodies.size(); ++i)
@@ -101,6 +101,35 @@ public:
return energy;
}
virtual double totalDampingEnergy(btScalar dt)
{
double energy = 0;
int sz = 0;
for (int i = 0; i < m_softBodies.size(); ++i)
{
btSoftBody* psb = m_softBodies[i];
for (int j = 0; j < psb->m_nodes.size(); ++j)
{
sz = btMax(sz, psb->m_nodes[j].index);
}
}
TVStack dampingForce;
dampingForce.resize(sz+1);
for (int i = 0; i < dampingForce.size(); ++i)
dampingForce[i].setZero();
addScaledDampingForce(0.5, dampingForce);
for (int i = 0; i < m_softBodies.size(); ++i)
{
btSoftBody* psb = m_softBodies[i];
for (int j = 0; j < psb->m_nodes.size(); ++j)
{
const btSoftBody::Node& node = psb->m_nodes[j];
energy -= dampingForce[node.index].dot(node.m_v) / dt;
}
}
return energy;
}
double elasticEnergyDensity(const btSoftBody::TetraScratch& s)
{
double density = 0;
@@ -168,7 +197,7 @@ public:
size_t id3 = node3->index;
btMatrix3x3 dF = Ds(id0, id1, id2, id3, dv) * tetra.m_Dm_inverse;
btMatrix3x3 dP;
firstPiolaDampingDifferential(psb->m_tetraScratches[j], dF, dP);
firstPiolaDampingDifferential(psb->m_tetraScratchesTn[j], dF, dP);
btVector3 df_on_node0 = dP * (tetra.m_Dm_inverse.transpose()*grad_N_hat_1st_col);
btMatrix3x3 df_on_node123 = dP * tetra.m_Dm_inverse.transpose();