int getFramesLoop(const UndirectedTree & undirected_tree,
const KDL::JntArray &q,
const Traversal & traversal,
std::vector<Frame> & X_base,
KDL::Frame world2base)
{
for(int i=0; i < (int)traversal.getNrOfVisitedLinks(); i++) {
double joint_pos;
LinkMap::const_iterator link_it = traversal.getOrderedLink(i);
int link_nmbr = link_it->getLinkIndex();
if( i == 0 ) {
assert( traversal.getParentLink(link_nmbr) == undirected_tree.getInvalidLinkIterator() );
X_base[link_nmbr] = world2base;
} else {
LinkMap::const_iterator parent_it = traversal.getParentLink(link_it);
int parent_nmbr = parent_it->getLinkIndex();
if( link_it->getAdjacentJoint(parent_it)->getJoint().getType() != Joint::None ) {
int dof_nr = link_it->getAdjacentJoint(parent_it)->getDOFIndex();
joint_pos = q(dof_nr);
} else {
joint_pos = 0.0;
}
KDL::Frame X_parent_son = link_it->pose(parent_it,joint_pos);
X_base[link_nmbr] = X_base[parent_nmbr]*X_parent_son;
}
}
return 0;
}
void checkComputeTraversal(const Model & model)
{
Traversal traversal;
bool ok = model.computeFullTreeTraversal(traversal);
ASSERT_EQUAL_DOUBLE(ok,true);
ASSERT_EQUAL_DOUBLE(traversal.getNrOfVisitedLinks(),model.getNrOfLinks());
}
void dynamicsRegressorLoop(const UndirectedTree & ,
const KDL::JntArray &q,
const Traversal & traversal,
const std::vector<Frame>& X_b,
const std::vector<Twist>& v,
const std::vector<Twist>& a,
Eigen::MatrixXd & dynamics_regressor)
{
dynamics_regressor.setZero();
Eigen::Matrix<double, 6, 10> netWrenchRegressor_i;
// Store the base_world translational transform in world orientation
KDL::Frame world_base_X_world_world = KDL::Frame(-(X_b[traversal.getBaseLink()->getLinkIndex()].p));
for(int l =(int)traversal.getNrOfVisitedLinks()-1; l >= 0; l-- ) {
LinkMap::const_iterator link = traversal.getOrderedLink(l);
int i = link->getLinkIndex();
//Each link affects the dynamics of the joints from itself to the base
netWrenchRegressor_i = netWrenchRegressor(v[i],a[i]);
//Base dynamics
// The base dynamics is expressed with the orientation of the world but
// with respect to the base origin
dynamics_regressor.block(0,(int)(10*i),6,10) = WrenchTransformationMatrix(world_base_X_world_world*X_b[i])*netWrenchRegressor_i;
//dynamics_regressor.block(0,(int)(10*i),6,10) = WrenchTransformationMatrix(X_b[i])*netWrenchRegressor_i;
LinkMap::const_iterator child_link = link;
LinkMap::const_iterator parent_link=traversal.getParentLink(link);
while( child_link != traversal.getOrderedLink(0) ) {
if( child_link->getAdjacentJoint(parent_link)->getNrOfDOFs() == 1 ) {
#ifndef NDEBUG
//std::cerr << "Calculating regressor columns for link " << link->getName() << " and joint " << child_link->getAdjacentJoint(parent_link)->getName() << std::endl;
#endif
int dof_index = child_link->getAdjacentJoint(parent_link)->getDOFIndex();
int child_index = child_link->getLinkIndex();
Frame X_j_i = X_b[child_index].Inverse()*X_b[i];
dynamics_regressor.block(6+dof_index,10*i,1,10) =
toEigen(parent_link->S(child_link,q(dof_index))).transpose()*WrenchTransformationMatrix(X_j_i)*netWrenchRegressor_i;
}
child_link = parent_link;
#ifndef NDEBUG
//std::cout << "Getting parent link of link of index " << child_link->getName() << " " << child_link->getLinkIndex() << std::endl;
//std::cout << "Current base " << traversal.order[0]->getName() << " " << traversal.order[0]->getLinkIndex() << std::endl;
#endif
parent_link = traversal.getParentLink(child_link);
}
}
}
bool Model::computeFullTreeTraversal(Traversal & traversal, const LinkIndex traversalBase) const
{
if( traversalBase < 0 || traversalBase >= (LinkIndex)this->getNrOfLinks() )
{
reportError("Model","computeFullTreeTraversal","requested traversalBase is out of bounds");
return false;
}
// Resetting the traversal for populating it
traversal.reset(*this);
// A link is considered visit when all its child (given the traversalBase)
// have been added to the traversal
std::deque<stackEl> linkToVisit;
// We add as first link the requested traversalBase
addBaseLinkToTraversal(*this,traversal,traversalBase,linkToVisit);
// while there is some link still to visit
while( linkToVisit.size() > 0 )
{
assert(linkToVisit.size() <= this->getNrOfLinks());
// DPS : we use linkToVisit as a stack
LinkConstPtr visitedLink = linkToVisit.back().link;
LinkConstPtr visitedLinkParent = linkToVisit.back().parent;
LinkIndex visitedLinkIndex = visitedLink->getIndex();
linkToVisit.pop_back();
for(unsigned int neigh_i=0; neigh_i < this->getNrOfNeighbors(visitedLinkIndex); neigh_i++ )
{
// add to the stack all the neighbors, except for parent link
// (if the visited link is the base one, add all the neighbors)
// the visited link is already in the Traversal, so we can use it
// to check for its parent
Neighbor neighb = this->getNeighbor(visitedLinkIndex,neigh_i);
if( visitedLinkParent == 0 || neighb.neighborLink != visitedLinkParent->getIndex() )
{
addLinkToTraversal(*this,traversal,neighb.neighborLink,
neighb.neighborJoint,visitedLink->getIndex(),linkToVisit);
}
}
}
// At this point the traversal should contain all the links
// of the model
assert(traversal.getNrOfVisitedLinks() == this->getNrOfLinks());
return true;
}
void dynamicsRegressorFixedBaseLoop(const UndirectedTree & ,
const KDL::JntArray &q,
const Traversal & traversal,
const std::vector<Frame>& X_b,
const std::vector<Twist>& v,
const std::vector<Twist>& a,
Eigen::MatrixXd & dynamics_regressor)
{
dynamics_regressor.setZero();
Eigen::Matrix<double, 6, 10> netWrenchRegressor_i;
for(int l =(int)traversal.getNrOfVisitedLinks()-1; l >= 0; l-- ) {
LinkMap::const_iterator link = traversal.getOrderedLink(l);
int i = link->getLinkIndex();
//Each link affects the dynamics of the joints from itself to the base
netWrenchRegressor_i = netWrenchRegressor(v[i],a[i]);
//dynamics_regressor.block(0,(int)(10*i),6,10) = WrenchTransformationMatrix(X_b[i])*netWrenchRegressor_i;
LinkMap::const_iterator child_link = link;
LinkMap::const_iterator parent_link=traversal.getParentLink(link);
while( child_link != traversal.getOrderedLink(0) ) {
if( child_link->getAdjacentJoint(parent_link)->getNrOfDOFs() == 1 ) {
int dof_index = child_link->getAdjacentJoint(parent_link)->getDOFIndex();
int child_index = child_link->getLinkIndex();
Frame X_j_i = X_b[child_index].Inverse()*X_b[i];
dynamics_regressor.block(dof_index,10*i,1,10) =
toEigen(parent_link->S(child_link,q(dof_index))).transpose()*WrenchTransformationMatrix(X_j_i)*netWrenchRegressor_i;
}
child_link = parent_link;
parent_link = traversal.getParentLink(child_link);
}
}
}
int crba_momentum_jacobian_loop(const UndirectedTree & undirected_tree,
const Traversal & traversal,
const JntArray & q,
std::vector<RigidBodyInertia> & Ic,
MomentumJacobian & H,
RigidBodyInertia & InertiaCOM
)
{
#ifndef NDEBUG
if( undirected_tree.getNrOfLinks() != traversal.getNrOfVisitedLinks() ||
undirected_tree.getNrOfDOFs() != q.rows() ||
Ic.size() != undirected_tree.getNrOfLinks() ||
H.columns() != (undirected_tree.getNrOfDOFs() + 6) )
{
std::cerr << "crba_momentum_jacobian_loop: input data error" << std::endl;
return -1;
}
#endif
double q_;
Wrench F = Wrench::Zero();
//Sweep from root to leaf
for(int i=0; i<(int)traversal.getNrOfVisitedLinks(); i++)
{
LinkMap::const_iterator link_it = traversal.getOrderedLink(i);
int link_index = link_it->getLinkIndex();
//Collect RigidBodyInertia
Ic[link_index]=link_it->getInertia();
}
for(int i=(int)traversal.getNrOfVisitedLinks()-1; i >= 1; i-- ) {
int dof_id;
LinkMap::const_iterator link_it = traversal.getOrderedLink(i);
int link_index = link_it->getLinkIndex();
LinkMap::const_iterator parent_it = traversal.getParentLink(link_index);
int parent_index = parent_it->getLinkIndex();
if( link_it->getAdjacentJoint(parent_it)->getNrOfDOFs() == 1 ) {
dof_id = link_it->getAdjacentJoint(parent_it)->getDOFIndex();
q_ = q(dof_id);
} else {
q_ = 0.0;
dof_id = -1;
}
Ic[parent_index] = Ic[parent_index]+link_it->pose(parent_it,q_)*Ic[link_index];
if( link_it->getAdjacentJoint(parent_it)->getNrOfDOFs() == 1 ) {
KDL::Twist S_link_parent = parent_it->S(link_it,q_);
F = Ic[link_index]*S_link_parent;
if( traversal.getParentLink(link_it) != undirected_tree.getInvalidLinkIterator() ) {
double q__;
int dof_id_;
LinkMap::const_iterator predecessor_it = traversal.getParentLink(link_it);
LinkMap::const_iterator successor_it = link_it;
while(true) {
if( predecessor_it->getAdjacentJoint(successor_it)->getNrOfDOFs() == 1 ) {
q__ = q( predecessor_it->getAdjacentJoint(successor_it)->getDOFIndex());
} else {
q__ = 0.0;
}
F = successor_it->pose(predecessor_it,q__)*F;
successor_it = predecessor_it;
predecessor_it = traversal.getParentLink(predecessor_it);
if( predecessor_it == undirected_tree.getInvalidLinkIterator() ) {
break;
}
if( predecessor_it->getAdjacentJoint(successor_it)->getNrOfDOFs() == 1 ) {
dof_id_ = predecessor_it->getAdjacentJoint(successor_it)->getDOFIndex();
q__ = q(dof_id_);
} else {
q__ = 0.0;
dof_id_ = -1;
}
}
if( dof_id >= 0 ) {
H.data.block(0,6+dof_id,6,1) = toEigen(F);
}
//The first 6x6 submatrix of the Momentum Jacobian are simply the spatial inertia
//of all the structure expressed in the base reference frame
H.data.block(0,0,6,6) = toEigen(Ic[traversal.getBaseLink()->getLinkIndex()]);
}
}
}
//We have then to translate the reference point of the obtained jacobian to the com
//The Ic[traversal.order[0]->getLink(index)] contain the spatial inertial of all the tree
//expressed in link coordite frames
Vector com = Ic[traversal.getBaseLink()->getLinkIndex()].getCOG();
H.changeRefPoint(com);
InertiaCOM = Frame(com)*Ic[traversal.getBaseLink()->getLinkIndex()];
return 0;
}
int crba_fixed_base_loop(const UndirectedTree & undirected_tree, const Traversal & traversal, const JntArray & q, std::vector<RigidBodyInertia> & Ic, JntSpaceInertiaMatrix & H) {
double q_;
Wrench F;
//Sweep from root to leaf
for(int i=0; i<(int)traversal.getNrOfVisitedLinks(); i++)
{
LinkMap::const_iterator link_it = traversal.getOrderedLink(i);
int link_index = link_it->getLinkIndex();
//Collect RigidBodyInertia
Ic[link_index] = link_it->getInertia();
}
for(int i=(int)traversal.getNrOfVisitedLinks()-1; i >= 1; i-- ) {
int dof_id;
LinkMap::const_iterator link_it = traversal.getOrderedLink(i);
int link_index = link_it->getLinkIndex();
LinkMap::const_iterator parent_it = traversal.getParentLink(link_index);
int parent_index = parent_it->getLinkIndex();
if( link_it->getAdjacentJoint(parent_it)->getNrOfDOFs() == 1 ) {
dof_id = link_it->getAdjacentJoint(parent_it)->getDOFIndex();
q_ = q(dof_id);
} else {
q_ = 0.0;
dof_id = -1;
}
Ic[parent_index] = Ic[parent_index]+link_it->pose(parent_it,q_)*Ic[link_index];
if( link_it->getAdjacentJoint(parent_it)->getNrOfDOFs() == 1 ) {
KDL::Twist S_link_parent = parent_it->S(link_it,q_);
F = Ic[link_index]*S_link_parent;
H(dof_id,dof_id) = dot(S_link_parent,F);
{
assert(parent_it != undirected_tree.getInvalidLinkIterator());
double q__;
int dof_id_;
LinkMap::const_iterator predecessor_it = traversal.getParentLink(link_it);
LinkMap::const_iterator successor_it = link_it;
while( true ) {
if( predecessor_it->getAdjacentJoint(successor_it)->getNrOfDOFs() == 1 ) {
q__ = q( predecessor_it->getAdjacentJoint(successor_it)->getDOFIndex());
} else {
q__ = 0.0;
}
F = successor_it->pose(predecessor_it,q__)*F;
successor_it = predecessor_it;
predecessor_it = traversal.getParentLink(predecessor_it);
if( predecessor_it == undirected_tree.getInvalidLinkIterator() ) {
break;
}
if( predecessor_it->getAdjacentJoint(successor_it)->getNrOfDOFs() == 1 ) {
dof_id_ = predecessor_it->getAdjacentJoint(successor_it)->getDOFIndex();
q__ = q(dof_id_);
} else {
q__ = 0.0;
dof_id_ = -1;
}
Twist S_successor_predecessor = predecessor_it->S(successor_it,q__);
if( dof_id_ >= 0 ) {
H(dof_id_,dof_id) = dot(S_successor_predecessor,F);
H(dof_id,dof_id_) = H(dof_id_,dof_id);
}
}
}
}
}
return 0;
}
int crba_floating_base_loop(const UndirectedTree & undirected_tree,
const Traversal & traversal,
const GeneralizedJntPositions & q,
std::vector<RigidBodyInertia> & Ic,
FloatingJntSpaceInertiaMatrix & H) {
Wrench F = Wrench::Zero();
Wrench buffer_F = F;
//Sweep from root to leaf
for(int i=0; i<(int)traversal.getNrOfVisitedLinks(); i++)
{
LinkMap::const_iterator link_it = traversal.getOrderedLink(i);
int link_index = link_it->getLinkIndex();
//Collect RigidBodyInertia
Ic[link_index]=link_it->getInertia();
}
for(int i=(int)traversal.getNrOfVisitedLinks()-1; i >= 1; i-- ) {
double row_dof_position;
int row_dof_id;
LinkMap::const_iterator link_it = traversal.getOrderedLink(i);
int link_index = link_it->getLinkIndex();
LinkMap::const_iterator parent_it = traversal.getParentLink(link_index);
int parent_index = parent_it->getLinkIndex();
if( link_it->getAdjacentJoint(parent_it)->getNrOfDOFs() == 1 ) {
row_dof_id = link_it->getAdjacentJoint(parent_it)->getDOFIndex();
row_dof_position = q.jnt_pos(row_dof_id);
} else {
row_dof_position = 0.0;
row_dof_id = -1;
}
RigidBodyInertia buf;
buf = Ic[parent_index]+link_it->pose(parent_it,row_dof_position)*Ic[link_index];
Ic[parent_index] = buf;
if( link_it->getAdjacentJoint(parent_it)->getNrOfDOFs() == 1 ) {
KDL::Twist S_link_parent = parent_it->S(link_it,row_dof_position);
F = Ic[link_index]*S_link_parent;
H(6+row_dof_id,6+row_dof_id) = dot(S_link_parent,F);
if( traversal.getParentLink(link_it) != undirected_tree.getInvalidLinkIterator() ) {
double column_dof_position;
int column_dof_id;
LinkMap::const_iterator predecessor_it = traversal.getParentLink(link_it);
LinkMap::const_iterator successor_it = link_it;
while(true) {
if( predecessor_it->getAdjacentJoint(successor_it)->getNrOfDOFs() == 1 ) {
column_dof_position = q.jnt_pos( predecessor_it->getAdjacentJoint(successor_it)->getDOFIndex());
} else {
column_dof_position = 0.0;
}
#ifndef NDEBUG
//std::cout << "F migrated from frame " << successor_it->getLinkIndex() << " to frame " << successor_it->getLinkIndex() << std::endl;
#endif
buffer_F = successor_it->pose(predecessor_it,column_dof_position)*F;
F = buffer_F;
successor_it = predecessor_it;
predecessor_it = traversal.getParentLink(predecessor_it);
if( predecessor_it == undirected_tree.getInvalidLinkIterator() ) {
break;
}
if( predecessor_it->getAdjacentJoint(successor_it)->getNrOfDOFs() == 1 ) {
column_dof_id = predecessor_it->getAdjacentJoint(successor_it)->getDOFIndex();
column_dof_position = q.jnt_pos(column_dof_id);
} else {
column_dof_position = 0.0;
column_dof_id = -1;
}
Twist S_successor_predecessor = predecessor_it->S(successor_it,column_dof_position);
if( column_dof_id >= 0 ) {
H(6+column_dof_id,6+row_dof_id) = dot(S_successor_predecessor,F);
H(6+row_dof_id,6+column_dof_id) = H(6+column_dof_id,6+row_dof_id);
}
}
if( row_dof_id >= 0 ) {
buffer_F = q.base_pos.M*F;
F = buffer_F;
H.data.block(0,6+row_dof_id,6,1) = toEigen(F);
H.data.block(6+row_dof_id,0,1,6) = toEigen(F).transpose();
}
}
}
}
//The first 6x6 submatrix of the FlotingBase Inertia Matrix are simply the spatial inertia
//of all the structure expressed in the base reference frame
H.data.block(0,0,6,6) = toEigen(q.base_pos.M*Ic[traversal.getBaseLink()->getLinkIndex()]);
return 0;
}