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fix InverseKinematics+API for a case without tree (custom build Jacobian)

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This commit is contained in:
erwin coumans
2016-09-22 13:27:09 -07:00
parent 46b32f17bb
commit 310a330572
12 changed files with 251 additions and 211 deletions
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143
examples/SharedMemory/IKTrajectoryHelper.cpp
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@@ -16,7 +16,7 @@ struct IKTrajectoryHelperInternalData
{
VectorR3 m_endEffectorTargetPosition;
Tree m_ikTree;
b3AlignedObjectArray<Node*> m_ikNodes;
Jacobian* m_ikJacobian;
@@ -37,82 +37,22 @@ IKTrajectoryHelper::~IKTrajectoryHelper()
delete m_data;
}
bool IKTrajectoryHelper::createFromMultiBody(class btMultiBody* mb)
{
//todo: implement proper conversion. For now, we only 'detect' a likely KUKA iiwa and hardcode its creation
if (mb->getNumLinks()==7)
{
createKukaIIWA();
return true;
}
return false;
}
void IKTrajectoryHelper::createKukaIIWA()
{
const VectorR3& unitx = VectorR3::UnitX;
const VectorR3& unity = VectorR3::UnitY;
const VectorR3& unitz = VectorR3::UnitZ;
const VectorR3 unit1(sqrt(14.0) / 8.0, 1.0 / 8.0, 7.0 / 8.0);
const VectorR3& zero = VectorR3::Zero;
float minTheta = -4 * PI;
float maxTheta = 4 * PI;
m_data->m_ikNodes.resize(8);//7DOF+additional endeffector
m_data->m_ikNodes[0] = new Node(VectorR3(0.100000, 0.000000, 0.087500), unitz, 0.08, JOINT, -1e30, 1e30, RADIAN(0.));
m_data->m_ikTree.InsertRoot(m_data->m_ikNodes[0]);
m_data->m_ikNodes[1] = new Node(VectorR3(0.100000, -0.000000, 0.290000), unity, 0.08, JOINT, -0.5, 0.4, RADIAN(0.));
m_data->m_ikTree.InsertLeftChild(m_data->m_ikNodes[0], m_data->m_ikNodes[1]);
m_data->m_ikNodes[2] = new Node(VectorR3(0.100000, -0.000000, 0.494500), unitz, 0.08, JOINT, minTheta, maxTheta, RADIAN(0.));
m_data->m_ikTree.InsertLeftChild(m_data->m_ikNodes[1], m_data->m_ikNodes[2]);
m_data->m_ikNodes[3] = new Node(VectorR3(0.100000, 0.000000, 0.710000), -unity, 0.08, JOINT, minTheta, maxTheta, RADIAN(0.));
m_data->m_ikTree.InsertLeftChild(m_data->m_ikNodes[2], m_data->m_ikNodes[3]);
m_data->m_ikNodes[4] = new Node(VectorR3(0.100000, 0.000000, 0.894500), unitz, 0.08, JOINT, minTheta, maxTheta, RADIAN(0.));
m_data->m_ikTree.InsertLeftChild(m_data->m_ikNodes[3], m_data->m_ikNodes[4]);
m_data->m_ikNodes[5] = new Node(VectorR3(0.100000, 0.000000, 1.110000), unity, 0.08, JOINT, minTheta, maxTheta, RADIAN(0.));
m_data->m_ikTree.InsertLeftChild(m_data->m_ikNodes[4], m_data->m_ikNodes[5]);
m_data->m_ikNodes[6] = new Node(VectorR3(0.100000, 0.000000, 1.191000), unitz, 0.08, JOINT, minTheta, maxTheta, RADIAN(0.));
m_data->m_ikTree.InsertLeftChild(m_data->m_ikNodes[5], m_data->m_ikNodes[6]);
m_data->m_ikNodes[7] = new Node(VectorR3(0.100000, 0.000000, 1.20000), zero, 0.08, EFFECTOR);
m_data->m_ikTree.InsertLeftChild(m_data->m_ikNodes[6], m_data->m_ikNodes[7]);
m_data->m_ikJacobian = new Jacobian(&m_data->m_ikTree);
// Reset(m_ikTree,m_ikJacobian);
m_data->m_ikTree.Init();
m_data->m_ikTree.Compute();
m_data->m_ikJacobian->Reset();
}
bool IKTrajectoryHelper::computeIK(const double endEffectorTargetPosition[3],
const double endEffectorTargetOrientation[4],
const double endEffectorWorldPosition[3],
const double endEffectorWorldOrientation[4],
const double* q_current, int numQ,
double* q_new, int ikMethod, const double* linear_jacobian, const double* angular_jacobian, int jacobian_size, float dt)
const double* q_current, int numQ,int endEffectorIndex,
double* q_new, int ikMethod, const double* linear_jacobian, const double* angular_jacobian, int jacobian_size)
{
bool useAngularPart = (ikMethod==IK2_VEL_DLS_WITH_ORIENTATION) ? true : false;
m_data->m_ikJacobian = new Jacobian(useAngularPart,numQ);
// Reset(m_ikTree,m_ikJacobian);
m_data->m_ikJacobian->Reset();
if (numQ != 7)
{
return false;
}
for (int i=0;i<numQ;i++)
{
m_data->m_ikNodes[i]->SetTheta(q_current[i]);
}
bool UseJacobianTargets1 = false;
if ( UseJacobianTargets1 ) {
@@ -129,7 +69,7 @@ bool IKTrajectoryHelper::computeIK(const double endEffectorTargetPosition[3],
VectorRn deltaS(3);
for (int i = 0; i < 3; ++i)
{
deltaS.Set(i,(endEffectorTargetPosition[i]-endEffectorWorldPosition[i])/dt);
deltaS.Set(i,(endEffectorTargetPosition[i]-endEffectorWorldPosition[i]));
}
// Set one end effector world orientation from Bullet
@@ -139,35 +79,49 @@ bool IKTrajectoryHelper::computeIK(const double endEffectorTargetPosition[3],
btQuaternion deltaQ = endQ*startQ.inverse();
float angle = deltaQ.getAngle();
btVector3 axis = deltaQ.getAxis();
float angleDot = angle/dt;
float angleDot = angle;
btVector3 angularVel = angleDot*axis.normalize();
for (int i = 0; i < 3; ++i)
{
deltaR.Set(i,angularVel[i]);
}
VectorRn deltaC(6);
for (int i = 0; i < 3; ++i)
{
deltaC.Set(i,deltaS[i]);
deltaC.Set(i+3,deltaR[i]);
}
m_data->m_ikJacobian->SetDeltaS(deltaC);
// Set Jacobian from Bullet body Jacobian
int nRow = m_data->m_ikJacobian->GetNumRows();
int nCol = m_data->m_ikJacobian->GetNumCols();
b3Assert(jacobian_size==nRow*nCol);
MatrixRmn completeJacobian(nRow,nCol);
for (int i = 0; i < nRow/2; ++i)
{
for (int j = 0; j < nCol; ++j)
{
completeJacobian.Set(i,j,linear_jacobian[i*nCol+j]);
completeJacobian.Set(i+nRow/2,j,angular_jacobian[i*nCol+j]);
}
if (useAngularPart)
{
VectorRn deltaC(6);
MatrixRmn completeJacobian(6,numQ);
for (int i = 0; i < 3; ++i)
{
deltaC.Set(i,deltaS[i]);
deltaC.Set(i+3,deltaR[i]);
for (int j = 0; j < numQ; ++j)
{
completeJacobian.Set(i,j,linear_jacobian[i*numQ+j]);
completeJacobian.Set(i+3,j,angular_jacobian[i*numQ+j]);
}
}
m_data->m_ikJacobian->SetDeltaS(deltaC);
m_data->m_ikJacobian->SetJendTrans(completeJacobian);
} else
{
VectorRn deltaC(3);
MatrixRmn completeJacobian(3,numQ);
for (int i = 0; i < 3; ++i)
{
deltaC.Set(i,deltaS[i]);
for (int j = 0; j < numQ; ++j)
{
completeJacobian.Set(i,j,linear_jacobian[i*numQ+j]);
}
}
m_data->m_ikJacobian->SetDeltaS(deltaC);
m_data->m_ikJacobian->SetJendTrans(completeJacobian);
}
}
m_data->m_ikJacobian->SetJendTrans(completeJacobian);
// Calculate the change in theta values
switch (ikMethod) {
@@ -175,6 +129,8 @@ bool IKTrajectoryHelper::computeIK(const double endEffectorTargetPosition[3],
m_data->m_ikJacobian->CalcDeltaThetasTranspose(); // Jacobian transpose method
break;
case IK2_DLS:
case IK2_VEL_DLS_WITH_ORIENTATION:
case IK2_VEL_DLS:
m_data->m_ikJacobian->CalcDeltaThetasDLS(); // Damped least squares method
break;
case IK2_DLS_SVD:
@@ -186,9 +142,6 @@ bool IKTrajectoryHelper::computeIK(const double endEffectorTargetPosition[3],
case IK2_SDLS:
m_data->m_ikJacobian->CalcDeltaThetasSDLS(); // Selectively damped least squares method
break;
case IK2_VEL_DLS:
m_data->m_ikJacobian->CalcThetasDotDLS(dt); // Damped least square for velocity IK
break;
default:
m_data->m_ikJacobian->ZeroDeltaThetas();
break;
@@ -206,7 +159,7 @@ bool IKTrajectoryHelper::computeIK(const double endEffectorTargetPosition[3],
for (int i=0;i<numQ;i++)
{
// Use for velocity IK
q_new[i] = m_data->m_ikNodes[i]->GetTheta()*dt + q_current[i];
q_new[i] = m_data->m_ikJacobian->dTheta[i] + q_current[i];
// Use for position IK
//q_new[i] = m_data->m_ikNodes[i]->GetTheta();