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add option for rigid body/typed constraint to set target velocity

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compare joint feedback between multi body and rigid body. initial results are promising (not exactly the same, but reasonably close)
This commit is contained in:
Erwin Coumans
2015-06-24 23:19:00 -07:00
parent b14afba350
commit d830681674
11 changed files with 426 additions and 164 deletions
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72
examples/Importers/ImportURDFDemo/ImportURDFSetup.cpp
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@@ -63,11 +63,18 @@ struct ImportUrdfInternalData
ImportUrdfInternalData()
:m_numMotors(0)
{
for (int i=0;i<MAX_NUM_MOTORS;i++)
{
m_jointMotors[i] = 0;
m_generic6DofJointMotors[i] = 0;
}
}
btScalar m_motorTargetVelocities[MAX_NUM_MOTORS];
btMultiBodyJointMotor* m_jointMotors [MAX_NUM_MOTORS];
btGeneric6DofSpring2Constraint* m_generic6DofJointMotors [MAX_NUM_MOTORS];
int m_numMotors;
};
@@ -91,8 +98,7 @@ ImportUrdfSetup::ImportUrdfSetup(struct GUIHelperInterface* helper, int option,
} else
{
gFileNameArray.clear();
gFileNameArray.push_back("r2d2.urdf");
//load additional urdf file names from file
@@ -115,6 +121,12 @@ ImportUrdfSetup::ImportUrdfSetup(struct GUIHelperInterface* helper, int option,
fclose(f);
}
if (gFileNameArray.size()==0)
{
gFileNameArray.push_back("r2d2.urdf");
}
int numFileNames = gFileNameArray.size();
@@ -175,7 +187,7 @@ void ImportUrdfSetup::initPhysics()
btVector3 gravity(0,0,0);
gravity[upAxis]=-9.8;
//gravity[upAxis]=-9.8;
m_dynamicsWorld->setGravity(gravity);
@@ -210,9 +222,7 @@ void ImportUrdfSetup::initPhysics()
if (m_useMultiBody)
{
//create motors for each joint
//create motors for each btMultiBody joint
for (int i=0;i<mb->getNumLinks();i++)
{
@@ -236,6 +246,7 @@ void ImportUrdfSetup::initPhysics()
m_guiHelper->getParameterInterface()->registerSliderFloatParameter(slider);
float maxMotorImpulse = 0.1f;
btMultiBodyJointMotor* motor = new btMultiBodyJointMotor(mb,mbLinkIndex,0,0,maxMotorImpulse);
//motor->setMaxAppliedImpulse(0);
m_data->m_jointMotors[m_data->m_numMotors]=motor;
m_dynamicsWorld->addMultiBodyConstraint(motor);
m_data->m_numMotors++;
@@ -243,6 +254,44 @@ void ImportUrdfSetup::initPhysics()
}
}
} else
{
if (1)
{
//create motors for each generic joint
for (int i=0;i<creation.getNum6DofConstraints();i++)
{
btGeneric6DofSpring2Constraint* c = creation.get6DofConstraint(i);
if (c->getUserConstraintPtr())
{
GenericConstraintUserInfo* jointInfo = (GenericConstraintUserInfo*)c->getUserConstraintPtr();
if ((jointInfo->m_urdfJointType ==URDFRevoluteJoint) ||
(jointInfo->m_urdfJointType ==URDFPrismaticJoint) ||
(jointInfo->m_urdfJointType ==URDFContinuousJoint))
{
int urdfLinkIndex = jointInfo->m_urdfIndex;
std::string jointName = u2b.getJointName(urdfLinkIndex);
char motorName[1024];
sprintf(motorName,"%s q'", jointName.c_str());
btScalar* motorVel = &m_data->m_motorTargetVelocities[m_data->m_numMotors];
*motorVel = 0.f;
SliderParams slider(motorName,motorVel);
slider.m_minVal=-4;
slider.m_maxVal=4;
m_guiHelper->getParameterInterface()->registerSliderFloatParameter(slider);
m_data->m_generic6DofJointMotors[m_data->m_numMotors]=c;
bool motorOn = true;
c->enableMotor(jointInfo->m_jointAxisIndex,motorOn);
c->setMaxMotorForce(jointInfo->m_jointAxisIndex,10000);
c->setTargetVelocity(jointInfo->m_jointAxisIndex,0);
m_data->m_numMotors++;
}
}
}
}
}
}
@@ -286,7 +335,16 @@ void ImportUrdfSetup::stepSimulation(float deltaTime)
{
for (int i=0;i<m_data->m_numMotors;i++)
{
m_data->m_jointMotors[i]->setVelocityTarget(m_data->m_motorTargetVelocities[i]);
if (m_data->m_jointMotors[i])
{
m_data->m_jointMotors[i]->setVelocityTarget(m_data->m_motorTargetVelocities[i]);
}
if (m_data->m_generic6DofJointMotors[i])
{
GenericConstraintUserInfo* jointInfo = (GenericConstraintUserInfo*)m_data->m_generic6DofJointMotors[i]->getUserConstraintPtr();
m_data->m_generic6DofJointMotors[i]->setTargetVelocity(jointInfo->m_jointAxisIndex,m_data->m_motorTargetVelocities[i]);
//jointInfo->
}
}
//the maximal coordinates/iterative MLCP solver requires a smallish timestep to converge

7
examples/Importers/ImportURDFDemo/MultiBodyCreationInterface.h
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@@ -21,6 +21,13 @@ public:
virtual class btGeneric6DofSpring2Constraint* allocateGeneric6DofSpring2Constraint(int urdfLinkIndex, btRigidBody& rbA /*parent*/, btRigidBody& rbB, const btTransform& offsetInA, const btTransform& offsetInB, int rotateOrder=0) = 0;
virtual class btGeneric6DofSpring2Constraint* createPrismaticJoint(int urdfLinkIndex, btRigidBody& rbA /*parent*/, btRigidBody& rbB, const btTransform& offsetInA, const btTransform& offsetInB,
const btVector3& jointAxisInJointSpace,btScalar jointLowerLimit,btScalar jointUpperLimit) = 0;
virtual class btGeneric6DofSpring2Constraint* createRevoluteJoint(int urdfLinkIndex, btRigidBody& rbA /*parent*/, btRigidBody& rbB, const btTransform& offsetInA, const btTransform& offsetInB,
const btVector3& jointAxisInJointSpace,btScalar jointLowerLimit,btScalar jointUpperLimit) = 0;
virtual class btGeneric6DofSpring2Constraint* createFixedJoint(int urdfLinkIndex, btRigidBody& rbA /*parent*/, btRigidBody& rbB, const btTransform& offsetInA, const btTransform& offsetInB) = 0;
virtual class btMultiBodyLinkCollider* allocateMultiBodyLinkCollider(int urdfLinkIndex, int mbLinkIndex, btMultiBody* body) = 0;
virtual void addLinkMapping(int urdfLinkIndex, int mbLinkIndex) = 0;

137
examples/Importers/ImportURDFDemo/MyMultiBodyCreator.cpp
View File

@@ -9,7 +9,7 @@
#include "btBulletDynamicsCommon.h"
#include "BulletDynamics/ConstraintSolver/btGeneric6DofSpring2Constraint.h"
#include "URDFJointTypes.h"
MyMultiBodyCreator::MyMultiBodyCreator(GUIHelperInterface* guiHelper)
:m_guiHelper(guiHelper),
@@ -42,12 +42,147 @@ class btMultiBodyLinkCollider* MyMultiBodyCreator::allocateMultiBodyLinkCollider
}
class btGeneric6DofSpring2Constraint* MyMultiBodyCreator::allocateGeneric6DofSpring2Constraint(int urdfLinkIndex, btRigidBody& rbA /*parent*/, btRigidBody& rbB, const btTransform& offsetInA, const btTransform& offsetInB, int rotateOrder)
{
btGeneric6DofSpring2Constraint* c = new btGeneric6DofSpring2Constraint(rbA,rbB,offsetInA, offsetInB, (RotateOrder)rotateOrder);
return c;
}
class btGeneric6DofSpring2Constraint* MyMultiBodyCreator::createPrismaticJoint(int urdfLinkIndex, btRigidBody& rbA /*parent*/, btRigidBody& rbB, const btTransform& offsetInA, const btTransform& offsetInB,
const btVector3& jointAxisInJointSpace,btScalar jointLowerLimit,btScalar jointUpperLimit)
{
int rotateOrder=0;
btGeneric6DofSpring2Constraint* dof6 = allocateGeneric6DofSpring2Constraint(urdfLinkIndex, rbA , rbB, offsetInA, offsetInB, rotateOrder);
//todo(erwincoumans) for now, we only support principle axis along X, Y or Z
int principleAxis = jointAxisInJointSpace.closestAxis();
GenericConstraintUserInfo* userInfo = new GenericConstraintUserInfo;
userInfo->m_jointAxisInJointSpace = jointAxisInJointSpace;
userInfo->m_jointAxisIndex = principleAxis;
userInfo->m_urdfJointType = URDFPrismaticJoint;
userInfo->m_lowerJointLimit = jointLowerLimit;
userInfo->m_upperJointLimit = jointUpperLimit;
userInfo->m_urdfIndex = urdfLinkIndex;
dof6->setUserConstraintPtr(userInfo);
switch (principleAxis)
{
case 0:
{
dof6->setLinearLowerLimit(btVector3(jointLowerLimit,0,0));
dof6->setLinearUpperLimit(btVector3(jointUpperLimit,0,0));
break;
}
case 1:
{
dof6->setLinearLowerLimit(btVector3(0,jointLowerLimit,0));
dof6->setLinearUpperLimit(btVector3(0,jointUpperLimit,0));
break;
}
case 2:
default:
{
dof6->setLinearLowerLimit(btVector3(0,0,jointLowerLimit));
dof6->setLinearUpperLimit(btVector3(0,0,jointUpperLimit));
}
};
dof6->setAngularLowerLimit(btVector3(0,0,0));
dof6->setAngularUpperLimit(btVector3(0,0,0));
m_6DofConstraints.push_back(dof6);
return dof6;
}
class btGeneric6DofSpring2Constraint* MyMultiBodyCreator::createRevoluteJoint(int urdfLinkIndex, btRigidBody& rbA /*parent*/, btRigidBody& rbB, const btTransform& offsetInA, const btTransform& offsetInB,
const btVector3& jointAxisInJointSpace,btScalar jointLowerLimit,btScalar jointUpperLimit)
{
btGeneric6DofSpring2Constraint* dof6 = 0;
//only handle principle axis at the moment,
//@todo(erwincoumans) orient the constraint for non-principal axis
int principleAxis = jointAxisInJointSpace.closestAxis();
switch (principleAxis)
{
case 0:
{
dof6 = allocateGeneric6DofSpring2Constraint(urdfLinkIndex,rbA, rbB, offsetInA, offsetInB,RO_ZYX);
dof6->setLinearLowerLimit(btVector3(0,0,0));
dof6->setLinearUpperLimit(btVector3(0,0,0));
dof6->setAngularUpperLimit(btVector3(-1,0,0));
dof6->setAngularLowerLimit(btVector3(1,0,0));
break;
}
case 1:
{
dof6 = allocateGeneric6DofSpring2Constraint(urdfLinkIndex,rbA, rbB, offsetInA, offsetInB,RO_XZY);
dof6->setLinearLowerLimit(btVector3(0,0,0));
dof6->setLinearUpperLimit(btVector3(0,0,0));
dof6->setAngularUpperLimit(btVector3(0,-1,0));
dof6->setAngularLowerLimit(btVector3(0,1,0));
break;
}
case 2:
default:
{
dof6 = allocateGeneric6DofSpring2Constraint(urdfLinkIndex,rbA, rbB, offsetInA, offsetInB,RO_XYZ);
dof6->setLinearLowerLimit(btVector3(0,0,0));
dof6->setLinearUpperLimit(btVector3(0,0,0));
dof6->setAngularUpperLimit(btVector3(0,0,-1));
dof6->setAngularLowerLimit(btVector3(0,0,0));
}
};
GenericConstraintUserInfo* userInfo = new GenericConstraintUserInfo;
userInfo->m_jointAxisInJointSpace = jointAxisInJointSpace;
userInfo->m_jointAxisIndex = 3+principleAxis;
if (jointLowerLimit > jointUpperLimit)
{
userInfo->m_urdfJointType = URDFContinuousJoint;
} else
{
userInfo->m_urdfJointType = URDFRevoluteJoint;
userInfo->m_lowerJointLimit = jointLowerLimit;
userInfo->m_upperJointLimit = jointUpperLimit;
userInfo->m_urdfIndex = urdfLinkIndex;
}
dof6->setUserConstraintPtr(userInfo);
m_6DofConstraints.push_back(dof6);
return dof6;
}
class btGeneric6DofSpring2Constraint* MyMultiBodyCreator::createFixedJoint(int urdfLinkIndex, btRigidBody& rbA /*parent*/, btRigidBody& rbB, const btTransform& offsetInA, const btTransform& offsetInB)
{
btGeneric6DofSpring2Constraint* dof6 = allocateGeneric6DofSpring2Constraint(urdfLinkIndex, rbA, rbB, offsetInA, offsetInB);
GenericConstraintUserInfo* userInfo = new GenericConstraintUserInfo;
userInfo->m_urdfIndex = urdfLinkIndex;
userInfo->m_urdfJointType = URDFFixedJoint;
dof6->setUserConstraintPtr(userInfo);
dof6->setLinearLowerLimit(btVector3(0,0,0));
dof6->setLinearUpperLimit(btVector3(0,0,0));
dof6->setAngularLowerLimit(btVector3(0,0,0));
dof6->setAngularUpperLimit(btVector3(0,0,0));
return dof6;
}
void MyMultiBodyCreator::addLinkMapping(int urdfLinkIndex, int mbLinkIndex)
{
// m_urdf2mbLink[urdfLinkIndex] = mbLinkIndex;

30
examples/Importers/ImportURDFDemo/MyMultiBodyCreator.h
View File

@@ -8,6 +8,17 @@
struct GUIHelperInterface;
class btMultiBody;
struct GenericConstraintUserInfo
{
int m_urdfIndex;
int m_urdfJointType;
btVector3 m_jointAxisInJointSpace;
int m_jointAxisIndex;
btScalar m_lowerJointLimit;
btScalar m_upperJointLimit;
};
class MyMultiBodyCreator : public MultiBodyCreationInterface
{
@@ -16,6 +27,7 @@ class MyMultiBodyCreator : public MultiBodyCreationInterface
struct GUIHelperInterface* m_guiHelper;
btAlignedObjectArray<btGeneric6DofSpring2Constraint*> m_6DofConstraints;
public:
@@ -37,12 +49,28 @@ public:
virtual class btGeneric6DofSpring2Constraint* allocateGeneric6DofSpring2Constraint(int urdfLinkIndex, btRigidBody& rbA /*parent*/, btRigidBody& rbB, const btTransform& offsetInA, const btTransform& offsetInB, int rotateOrder=0);
virtual class btGeneric6DofSpring2Constraint* createPrismaticJoint(int urdfLinkIndex, btRigidBody& rbA /*parent*/, btRigidBody& rbB, const btTransform& offsetInA, const btTransform& offsetInB,
const btVector3& jointAxisInJointSpace,btScalar jointLowerLimit,btScalar jointUpperLimit);
virtual class btGeneric6DofSpring2Constraint* createRevoluteJoint(int urdfLinkIndex, btRigidBody& rbA /*parent*/, btRigidBody& rbB, const btTransform& offsetInA, const btTransform& offsetInB,
const btVector3& jointAxisInJointSpace,btScalar jointLowerLimit,btScalar jointUpperLimit);
virtual class btGeneric6DofSpring2Constraint* createFixedJoint(int urdfLinkIndex, btRigidBody& rbA /*parent*/, btRigidBody& rbB, const btTransform& offsetInA, const btTransform& offsetInB);
virtual class btMultiBodyLinkCollider* allocateMultiBodyLinkCollider(int urdfLinkIndex, int mbLinkIndex, btMultiBody* body);
virtual void addLinkMapping(int urdfLinkIndex, int mbLinkIndex);
btMultiBody* getBulletMultiBody();
int getNum6DofConstraints() const
{
return m_6DofConstraints.size();
}
btGeneric6DofSpring2Constraint* get6DofConstraint(int index)
{
return m_6DofConstraints[index];
}
};
#endif //MY_MULTIBODY_CREATOR

93
examples/Importers/ImportURDFDemo/URDF2Bullet.cpp
View File

@@ -295,21 +295,9 @@ void ConvertURDF2BulletInternal(const URDFImporterInterface& u2b, MultiBodyCreat
} else
{
printf("Fixed joint\n");
btMatrix3x3 rm(offsetInA.getBasis());
btScalar y,p,r;
rm.getEulerZYX(y,p,r);
printf("y=%f,p=%f,r=%f\n", y,p,r);
//we could also use btFixedConstraint but it has some issues
btGeneric6DofSpring2Constraint* dof6 = creation.allocateGeneric6DofSpring2Constraint(urdfLinkIndex, *parentRigidBody, *linkRigidBody, offsetInA, offsetInB);
dof6->setLinearLowerLimit(btVector3(0,0,0));
dof6->setLinearUpperLimit(btVector3(0,0,0));
dof6->setAngularLowerLimit(btVector3(0,0,0));
dof6->setAngularUpperLimit(btVector3(0,0,0));
btGeneric6DofSpring2Constraint* dof6 = creation.createFixedJoint(urdfLinkIndex,*parentRigidBody, *linkRigidBody, offsetInA, offsetInB);
if (enableConstraints)
world1->addConstraint(dof6,true);
}
@@ -330,51 +318,11 @@ void ConvertURDF2BulletInternal(const URDFImporterInterface& u2b, MultiBodyCreat
} else
{
//only handle principle axis at the moment,
//@todo(erwincoumans) orient the constraint for non-principal axis
int principleAxis = jointAxisInJointSpace.closestAxis();
switch (principleAxis)
{
case 0:
{
btGeneric6DofSpring2Constraint* dof6 = creation.allocateGeneric6DofSpring2Constraint(urdfLinkIndex,*parentRigidBody, *linkRigidBody, offsetInA, offsetInB,RO_ZYX);
dof6->setLinearLowerLimit(btVector3(0,0,0));
dof6->setLinearUpperLimit(btVector3(0,0,0));
dof6->setAngularUpperLimit(btVector3(-1,0,0));
dof6->setAngularLowerLimit(btVector3(1,0,0));
btGeneric6DofSpring2Constraint* dof6 = creation.createRevoluteJoint(urdfLinkIndex,*parentRigidBody, *linkRigidBody, offsetInA, offsetInB,jointAxisInJointSpace,jointLowerLimit, jointUpperLimit);
if (enableConstraints)
if (enableConstraints)
world1->addConstraint(dof6,true);
break;
}
case 1:
{
btGeneric6DofSpring2Constraint* dof6 = creation.allocateGeneric6DofSpring2Constraint(urdfLinkIndex,*parentRigidBody, *linkRigidBody, offsetInA, offsetInB,RO_XZY);
dof6->setLinearLowerLimit(btVector3(0,0,0));
dof6->setLinearUpperLimit(btVector3(0,0,0));
dof6->setAngularUpperLimit(btVector3(0,-1,0));
dof6->setAngularLowerLimit(btVector3(0,1,0));
if (enableConstraints)
world1->addConstraint(dof6,true);
break;
}
case 2:
default:
{
btGeneric6DofSpring2Constraint* dof6 = creation.allocateGeneric6DofSpring2Constraint(urdfLinkIndex,*parentRigidBody, *linkRigidBody, offsetInA, offsetInB,RO_XYZ);
dof6->setLinearLowerLimit(btVector3(0,0,0));
dof6->setLinearUpperLimit(btVector3(0,0,0));
dof6->setAngularUpperLimit(btVector3(0,0,-1));
dof6->setAngularLowerLimit(btVector3(0,0,0));
if (enableConstraints)
world1->addConstraint(dof6,true);
}
};
printf("Revolute/Continuous joint\n");
}
break;
@@ -396,33 +344,10 @@ void ConvertURDF2BulletInternal(const URDFImporterInterface& u2b, MultiBodyCreat
} else
{
btGeneric6DofSpring2Constraint* dof6 = creation.allocateGeneric6DofSpring2Constraint(urdfLinkIndex,*parentRigidBody, *linkRigidBody, offsetInA, offsetInB);
//todo(erwincoumans) for now, we only support principle axis along X, Y or Z
int principleAxis = jointAxisInJointSpace.closestAxis();
switch (principleAxis)
{
case 0:
{
dof6->setLinearLowerLimit(btVector3(jointLowerLimit,0,0));
dof6->setLinearUpperLimit(btVector3(jointUpperLimit,0,0));
break;
}
case 1:
{
dof6->setLinearLowerLimit(btVector3(0,jointLowerLimit,0));
dof6->setLinearUpperLimit(btVector3(0,jointUpperLimit,0));
break;
}
case 2:
default:
{
dof6->setLinearLowerLimit(btVector3(0,0,jointLowerLimit));
dof6->setLinearUpperLimit(btVector3(0,0,jointUpperLimit));
}
};
dof6->setAngularLowerLimit(btVector3(0,0,0));
dof6->setAngularUpperLimit(btVector3(0,0,0));
btGeneric6DofSpring2Constraint* dof6 = creation.createPrismaticJoint(urdfLinkIndex,*parentRigidBody, *linkRigidBody, offsetInA, offsetInB,jointAxisInJointSpace,jointLowerLimit,jointUpperLimit);
if (enableConstraints)
world1->addConstraint(dof6,true);