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implement joint reaction forces for mobilizer motor/limit, by passing the constraint forces as 'external forces' and going through the Articulated Body Algorithm

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minor refactor for forwardKinematics, store the cached world transform in each btMultiBody::link
This commit is contained in:
erwin coumans
2015-06-19 15:51:24 -07:00
parent 89edc40d61
commit 6e9eb13235
9 changed files with 178 additions and 91 deletions
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108
src/BulletDynamics/Featherstone/btMultiBodyDynamicsWorld.cpp
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@@ -399,40 +399,10 @@ void btMultiBodyDynamicsWorld::forwardKinematics()
btAlignedObjectArray<btQuaternion> world_to_local;
btAlignedObjectArray<btVector3> local_origin;
for (int b=0;b<m_multiBodies.size();b++)
{
btMultiBody* bod = m_multiBodies[b];
int nLinks = bod->getNumLinks();
///base + num m_links
world_to_local.resize(nLinks+1);
local_origin.resize(nLinks+1);
world_to_local[0] = bod->getWorldToBaseRot();
local_origin[0] = bod->getBasePos();
for (int k=0;k<bod->getNumLinks();k++)
{
const int parent = bod->getParent(k);
world_to_local[k+1] = bod->getParentToLocalRot(k) * world_to_local[parent+1];
local_origin[k+1] = local_origin[parent+1] + (quatRotate(world_to_local[k+1].inverse() , bod->getRVector(k)));
}
for (int link=0;link<bod->getNumLinks();link++)
{
int index = link+1;
btVector3 posr = local_origin[index];
btScalar quat[4]={-world_to_local[index].x(),-world_to_local[index].y(),-world_to_local[index].z(),world_to_local[index].w()};
btTransform tr;
tr.setIdentity();
tr.setOrigin(posr);
tr.setRotation(btQuaternion(quat[0],quat[1],quat[2],quat[3]));
bod->getLink(link).m_worldPosition = posr;
}
bod->forwardKinematics(world_to_local,local_origin);
}
}
void btMultiBodyDynamicsWorld::solveConstraints(btContactSolverInfo& solverInfo)
@@ -507,10 +477,7 @@ void btMultiBodyDynamicsWorld::solveConstraints(btContactSolverInfo& solverInfo)
}
}
m_solverMultiBodyIslandCallback->processConstraints();
m_constraintSolver->allSolved(solverInfo, m_debugDrawer);
{
BT_PROFILE("btMultiBody stepVelocities");
@@ -709,6 +676,11 @@ void btMultiBodyDynamicsWorld::solveConstraints(btContactSolverInfo& solverInfo)
}
}
m_solverMultiBodyIslandCallback->processConstraints();
m_constraintSolver->allSolved(solverInfo, m_debugDrawer);
}
@@ -850,8 +822,8 @@ void btMultiBodyDynamicsWorld::debugDrawWorld()
{
BT_PROFILE("btMultiBody debugDrawWorld");
btAlignedObjectArray<btQuaternion> world_to_local;
btAlignedObjectArray<btVector3> local_origin;
btAlignedObjectArray<btQuaternion> world_to_local1;
btAlignedObjectArray<btVector3> local_origin1;
for (int c=0;c<m_multiBodyConstraints.size();c++)
{
@@ -862,52 +834,40 @@ void btMultiBodyDynamicsWorld::debugDrawWorld()
for (int b = 0; b<m_multiBodies.size(); b++)
{
btMultiBody* bod = m_multiBodies[b];
int nLinks = bod->getNumLinks();
///base + num m_links
world_to_local.resize(nLinks + 1);
local_origin.resize(nLinks + 1);
world_to_local[0] = bod->getWorldToBaseRot();
local_origin[0] = bod->getBasePos();
bod->forwardKinematics(world_to_local1,local_origin1);
{
btVector3 posr = local_origin[0];
// float pos[4]={posr.x(),posr.y(),posr.z(),1};
btScalar quat[4] = { -world_to_local[0].x(), -world_to_local[0].y(), -world_to_local[0].z(), world_to_local[0].w() };
btTransform tr;
tr.setIdentity();
tr.setOrigin(posr);
tr.setRotation(btQuaternion(quat[0], quat[1], quat[2], quat[3]));
getDebugDrawer()->drawTransform(tr, 0.1);
}
for (int k = 0; k<bod->getNumLinks(); k++)
{
const int parent = bod->getParent(k);
world_to_local[k + 1] = bod->getParentToLocalRot(k) * world_to_local[parent + 1];
local_origin[k + 1] = local_origin[parent + 1] + (quatRotate(world_to_local[k + 1].inverse(), bod->getRVector(k)));
}
getDebugDrawer()->drawTransform(bod->getBaseWorldTransform(), 0.1);
int nLinks = bod->getNumLinks();
for (int m = 0; m<bod->getNumLinks(); m++)
{
int link = m;
int index = link + 1;
btVector3 posr = local_origin[index];
// float pos[4]={posr.x(),posr.y(),posr.z(),1};
btScalar quat[4] = { -world_to_local[index].x(), -world_to_local[index].y(), -world_to_local[index].z(), world_to_local[index].w() };
btTransform tr;
tr.setIdentity();
tr.setOrigin(posr);
tr.setRotation(btQuaternion(quat[0], quat[1], quat[2], quat[3]));
const btTransform& tr = bod->getLink(m).m_cachedWorldTransform;
getDebugDrawer()->drawTransform(tr, 0.1);
//draw the joint axis
if (bod->getLink(m).m_jointType==btMultibodyLink::eRevolute)
{
btVector3 vec = quatRotate(tr.getRotation(),bod->getLink(m).m_axes[0].m_topVec);
btVector4 color(0,0,0,1);//1,1,1);
btVector3 from = vec+tr.getOrigin()-quatRotate(tr.getRotation(),bod->getLink(m).m_dVector);
btVector3 to = tr.getOrigin()-quatRotate(tr.getRotation(),bod->getLink(m).m_dVector);
getDebugDrawer()->drawLine(from,to,color);
}
if (bod->getLink(m).m_jointType==btMultibodyLink::ePrismatic)
{
btVector3 vec = quatRotate(tr.getRotation(),bod->getLink(m).m_axes[0].m_bottomVec);
btVector4 color(0,0,0,1);//1,1,1);
btVector3 from = vec+tr.getOrigin()-quatRotate(tr.getRotation(),bod->getLink(m).m_dVector);
btVector3 to = tr.getOrigin()-quatRotate(tr.getRotation(),bod->getLink(m).m_dVector);
getDebugDrawer()->drawLine(from,to,color);
}
}
}
}