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expose gear erp/relative position target to C-API/pybullet

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finish much better C++ vrSyncPlugin, running in-the-loop with the physics at high frequency, see also vr_kuka_setup_vrSyncPlugin.py
This commit is contained in:
erwincoumans
2017-09-26 19:54:36 -07:00
parent b1f8eb74a4
commit 8a265b8af2
12 changed files with 301 additions and 31 deletions
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4
data/pr2_gripper.urdf
View File

@@ -24,7 +24,7 @@
<joint name="left_gripper_joint" type="revolute">
<axis xyz="0 0 1"/>
<limit effort="1000.0" lower="0.0" upper="0.548" velocity="0.5"/>
<limit effort="1000.0" lower="-2.0" upper="2.548" velocity="0.5"/>
<origin rpy="0 0 0" xyz="0.2 0.01 0"/>
<parent link="gripper_pole"/>
<child link="left_gripper"/>
@@ -83,7 +83,7 @@
<joint name="right_gripper_joint" type="revolute">
<axis xyz="0 0 -1"/>
<limit effort="1000.0" lower="0.0" upper="0.548" velocity="0.5"/>
<limit effort="1000.0" lower="-2.0" upper="2." velocity="0.5"/>
<origin rpy="0 0 0" xyz="0.2 -0.01 0"/>
<parent link="gripper_pole"/>
<child link="right_gripper"/>

25
examples/SharedMemory/PhysicsClientC_API.cpp
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@@ -2131,6 +2131,31 @@ B3_SHARED_API int b3InitChangeUserConstraintSetGearAuxLink(b3SharedMemoryCommand
return 0;
}
B3_SHARED_API int b3InitChangeUserConstraintSetRelativePositionTarget(b3SharedMemoryCommandHandle commandHandle, double relativePositionTarget)
{
struct SharedMemoryCommand* command = (struct SharedMemoryCommand*) commandHandle;
b3Assert(command);
b3Assert(command->m_type == CMD_USER_CONSTRAINT);
b3Assert(command->m_updateFlags & USER_CONSTRAINT_CHANGE_CONSTRAINT);
command->m_updateFlags |=USER_CONSTRAINT_CHANGE_RELATIVE_POSITION_TARGET;
command->m_userConstraintArguments.m_relativePositionTarget = relativePositionTarget;
return 0;
}
B3_SHARED_API int b3InitChangeUserConstraintSetERP(b3SharedMemoryCommandHandle commandHandle, double erp)
{
struct SharedMemoryCommand* command = (struct SharedMemoryCommand*) commandHandle;
b3Assert(command);
b3Assert(command->m_type == CMD_USER_CONSTRAINT);
b3Assert(command->m_updateFlags & USER_CONSTRAINT_CHANGE_CONSTRAINT);
command->m_updateFlags |=USER_CONSTRAINT_CHANGE_ERP;
command->m_userConstraintArguments.m_erp = erp;
return 0;
}
B3_SHARED_API b3SharedMemoryCommandHandle b3InitRemoveUserConstraintCommand(b3PhysicsClientHandle physClient, int userConstraintUniqueId)
{

2
examples/SharedMemory/PhysicsClientC_API.h
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@@ -136,6 +136,8 @@ B3_SHARED_API int b3InitChangeUserConstraintSetFrameInB(b3SharedMemoryCommandHan
B3_SHARED_API int b3InitChangeUserConstraintSetMaxForce(b3SharedMemoryCommandHandle commandHandle, double maxAppliedForce);
B3_SHARED_API int b3InitChangeUserConstraintSetGearRatio(b3SharedMemoryCommandHandle commandHandle, double gearRatio);
B3_SHARED_API int b3InitChangeUserConstraintSetGearAuxLink(b3SharedMemoryCommandHandle commandHandle, int gearAuxLink);
B3_SHARED_API int b3InitChangeUserConstraintSetRelativePositionTarget(b3SharedMemoryCommandHandle commandHandle, double relativePositionTarget);
B3_SHARED_API int b3InitChangeUserConstraintSetERP(b3SharedMemoryCommandHandle commandHandle, double erp);
B3_SHARED_API b3SharedMemoryCommandHandle b3InitRemoveUserConstraintCommand(b3PhysicsClientHandle physClient, int userConstraintUniqueId);

9
examples/SharedMemory/PhysicsServerCommandProcessor.cpp
View File

@@ -7278,6 +7278,15 @@ bool PhysicsServerCommandProcessor::processCommand(const struct SharedMemoryComm
{
userConstraintPtr->m_mbConstraint->setGearRatio(clientCmd.m_userConstraintArguments.m_gearRatio);
}
if (clientCmd.m_updateFlags & USER_CONSTRAINT_CHANGE_RELATIVE_POSITION_TARGET)
{
userConstraintPtr->m_mbConstraint->setRelativePositionTarget(clientCmd.m_userConstraintArguments.m_relativePositionTarget);
}
if (clientCmd.m_updateFlags & USER_CONSTRAINT_CHANGE_ERP)
{
userConstraintPtr->m_mbConstraint->setErp(clientCmd.m_userConstraintArguments.m_erp);
}
if (clientCmd.m_updateFlags & USER_CONSTRAINT_CHANGE_GEAR_AUX_LINK)
{
userConstraintPtr->m_mbConstraint->setGearAuxLink(clientCmd.m_userConstraintArguments.m_gearAuxLink);

2
examples/SharedMemory/SharedMemoryCommands.h
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@@ -679,6 +679,8 @@ enum EnumUserConstraintFlags
USER_CONSTRAINT_REQUEST_INFO=64,
USER_CONSTRAINT_CHANGE_GEAR_RATIO=128,
USER_CONSTRAINT_CHANGE_GEAR_AUX_LINK=256,
USER_CONSTRAINT_CHANGE_RELATIVE_POSITION_TARGET=512,
USER_CONSTRAINT_CHANGE_ERP=1024,
};

2
examples/SharedMemory/SharedMemoryPublic.h
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@@ -247,6 +247,8 @@ struct b3UserConstraint
int m_userConstraintUniqueId;
double m_gearRatio;
int m_gearAuxLink;
double m_relativePositionTarget;
double m_erp;
};

105
examples/SharedMemory/plugins/vrSyncPlugin/vrSyncPlugin.cpp
View File

@@ -6,7 +6,6 @@
//plugin = p.loadPlugin("e:/develop/bullet3/bin/pybullet_vrSyncPlugin_vs2010_x64_release.dll")
//could also be plugin = p.loadPlugin("vrSyncPlugin.so") on Mac/Linux
//controllerId = 3
//p.executePluginCommand(plugin ,"bla", [controllerId,pr2_cid],[50])
#include "vrSyncPlugin.h"
#include "../../SharedMemoryPublic.h"
@@ -19,12 +18,18 @@ struct MyClass
int m_controllerId;
int m_constraintId;
int m_constraintId2;
int m_gripperId;
float m_maxForce;
float m_maxForce2;
MyClass()
:m_testData(42),
m_controllerId(-1),
m_constraintId(-1),
m_maxForce(0)
m_constraintId2(-1),
m_gripperId(-1),
m_maxForce(0),
m_maxForce2(0)
{
}
virtual ~MyClass()
@@ -66,6 +71,10 @@ B3_SHARED_API int preTickPluginCallback(struct b3PluginContext* context)
b3VRControllerEvent& event = vrEvents.m_controllerEvents[n];
if (event.m_controllerId ==obj->m_controllerId)
{
if (obj->m_constraintId>=0)
{
//this is basically equivalent to doing this in Python/pybullet:
//p.changeConstraint(pr2_cid, e[POSITION], e[ORIENTATION], maxForce=...)
b3SharedMemoryCommandHandle commandHandle;
int userConstraintUniqueId = obj->m_constraintId;
commandHandle = b3InitChangeUserConstraintCommand(context->m_physClient, userConstraintUniqueId);
@@ -74,10 +83,83 @@ B3_SHARED_API int preTickPluginCallback(struct b3PluginContext* context)
double orn[4] = {event.m_orn[0],event.m_orn[1],event.m_orn[2],event.m_orn[3]};
b3InitChangeUserConstraintSetFrameInB(commandHandle, orn);
b3InitChangeUserConstraintSetMaxForce(commandHandle, obj->m_maxForce);
b3SharedMemoryStatusHandle statusHandle = b3SubmitClientCommandAndWaitStatus(context->m_physClient, commandHandle);
//this is basically equivalent to doing this in Python/pybullet:
//p.changeConstraint(pr2_cid, e[POSITION], e[ORIENTATION], maxForce=500)
}
// apply the analogue button to close the constraint, using a gear constraint with position target
if (obj->m_constraintId2>=0)
{
//this block is similar to
//p.changeConstraint(c,gearRatio=1, erp=..., relativePositionTarget=relPosTarget, maxForce=...)
//printf("obj->m_constraintId2=%d\n", obj->m_constraintId2);
b3SharedMemoryCommandHandle commandHandle;
commandHandle = b3InitChangeUserConstraintCommand(context->m_physClient, obj->m_constraintId2);
//0 -> open, 1 = closed
double openPos = 1.;
double relPosTarget = openPos - (event.m_analogAxis*openPos);
b3InitChangeUserConstraintSetRelativePositionTarget(commandHandle, relPosTarget);
b3InitChangeUserConstraintSetERP(commandHandle,1);
b3SharedMemoryStatusHandle statusHandle = b3SubmitClientCommandAndWaitStatus(context->m_physClient, commandHandle);
}
//printf("event.m_analogAxis=%f\n", event.m_analogAxis);
// use the pr2_gripper motors to keep the gripper centered/symmetric around the center axis
if (obj->m_gripperId>=0)
{
//this block is similar to
//b = p.getJointState(pr2_gripper,2)[0]
//print("b = " + str(b))
//p.setJointMotorControl2(pr2_gripper, 0, p.POSITION_CONTROL, targetPosition=b, force=3)
//printf("obj->m_gripperId=%d\n", obj->m_gripperId);
{
b3SharedMemoryCommandHandle cmd_handle =
b3RequestActualStateCommandInit(context->m_physClient, obj->m_gripperId);
b3SharedMemoryStatusHandle status_handle =
b3SubmitClientCommandAndWaitStatus(context->m_physClient, cmd_handle);
int status_type = b3GetStatusType(status_handle);
if (status_type == CMD_ACTUAL_STATE_UPDATE_COMPLETED)
{
//printf("status_type == CMD_ACTUAL_STATE_UPDATE_COMPLETED\n");
b3JointSensorState sensorState;
if (b3GetJointState(context->m_physClient, status_handle, 2, &sensorState))
{
b3SharedMemoryCommandHandle commandHandle;
double targetPosition = sensorState.m_jointPosition;
//printf("targetPosition =%f\n", targetPosition);
if (1)
{
b3JointInfo info;
b3GetJointInfo(context->m_physClient, obj->m_gripperId, 0, &info);
commandHandle = b3JointControlCommandInit2(context->m_physClient, obj->m_gripperId, CONTROL_MODE_POSITION_VELOCITY_PD);
double kp = .1;
double targetVelocity = 0;
double kd = .6;
b3JointControlSetDesiredPosition(commandHandle, info.m_qIndex, targetPosition);
b3JointControlSetKp(commandHandle, info.m_uIndex, kp);
b3JointControlSetDesiredVelocity(commandHandle, info.m_uIndex,targetVelocity);
b3JointControlSetKd(commandHandle, info.m_uIndex, kd);
b3JointControlSetMaximumForce(commandHandle, info.m_uIndex, obj->m_maxForce2);
b3SubmitClientCommandAndWaitStatus(context->m_physClient, cmd_handle);
}
} else
{
//printf("???\n");
}
} else
{
//printf("no\n");
}
}
}
}
}
}
@@ -92,15 +174,26 @@ B3_SHARED_API int preTickPluginCallback(struct b3PluginContext* context)
B3_SHARED_API int executePluginCommand(struct b3PluginContext* context, const struct b3PluginArguments* arguments)
{
MyClass* obj = (MyClass*) context->m_userPointer;
if (arguments->m_numInts>=2 && arguments->m_numFloats >= 0)
if (arguments->m_numInts>=4 && arguments->m_numFloats >= 2)
{
obj->m_constraintId = arguments->m_ints[1];
obj->m_constraintId2 = arguments->m_ints[2];
obj->m_gripperId = arguments->m_ints[3];
printf("obj->m_constraintId=%d\n", obj->m_constraintId);
obj->m_maxForce = arguments->m_floats[0];
obj->m_maxForce2 = arguments->m_floats[1];
printf("obj->m_maxForce = %f\n", obj->m_maxForce);
obj->m_controllerId = arguments->m_ints[0];
printf("obj->m_controllerId=%d\n", obj->m_controllerId);
b3SharedMemoryCommandHandle command = b3InitSyncBodyInfoCommand(context->m_physClient);
b3SharedMemoryStatusHandle statusHandle = b3SubmitClientCommandAndWaitStatus(context->m_physClient, command);
int statusType = b3GetStatusType(statusHandle);
if (statusType != CMD_SYNC_BODY_INFO_COMPLETED)
{
}
}
return 0;
}

107
examples/pybullet/examples/vr_kuka_setup_vrSyncPlugin.py Normal file
View File

@@ -0,0 +1,107 @@
import pybullet as p
import time
#p.connect(p.UDP,"192.168.86.100")
cid = p.connect(p.SHARED_MEMORY)
if (cid<0):
p.connect(p.GUI)
p.resetSimulation()
#disable rendering during loading makes it much faster
p.configureDebugVisualizer(p.COV_ENABLE_RENDERING, 0)
objects = [p.loadURDF("plane.urdf", 0.000000,0.000000,0.000000,0.000000,0.000000,0.000000,1.000000)]
#objects = [p.loadURDF("samurai.urdf", 0.000000,0.000000,0.000000,0.000000,0.000000,0.000000,1.000000)]
objects = [p.loadURDF("pr2_gripper.urdf", 0.500000,0.300006,0.700000,-0.000000,-0.000000,-0.000031,1.000000)]
pr2_gripper = objects[0]
print ("pr2_gripper=")
print (pr2_gripper)
jointPositions=[ 0.550569, 0.000000, 0.549657, 0.000000 ]
for jointIndex in range (p.getNumJoints(pr2_gripper)):
p.resetJointState(pr2_gripper,jointIndex,jointPositions[jointIndex])
p.setJointMotorControl2(pr2_gripper,jointIndex,p.POSITION_CONTROL,targetPosition=0,force=0)
pr2_cid = p.createConstraint(pr2_gripper,-1,-1,-1,p.JOINT_FIXED,[0,0,0],[0.2,0,0],[0.500000,0.300006,0.700000])
print ("pr2_cid")
print (pr2_cid)
pr2_cid2 = p.createConstraint(pr2_gripper,0,pr2_gripper,2,jointType=p.JOINT_GEAR,jointAxis =[0,1,0],parentFramePosition=[0,0,0],childFramePosition=[0,0,0])
p.changeConstraint(pr2_cid2,gearRatio=1, erp=0.5, relativePositionTarget=0.5, maxForce=3)
objects = [p.loadURDF("kuka_iiwa/model_vr_limits.urdf", 1.400000,-0.200000,0.600000,0.000000,0.000000,0.000000,1.000000)]
kuka = objects[0]
jointPositions=[ -0.000000, -0.000000, 0.000000, 1.570793, 0.000000, -1.036725, 0.000001 ]
for jointIndex in range (p.getNumJoints(kuka)):
p.resetJointState(kuka,jointIndex,jointPositions[jointIndex])
p.setJointMotorControl2(kuka,jointIndex,p.POSITION_CONTROL,jointPositions[jointIndex],0)
objects = [p.loadURDF("lego/lego.urdf", 1.000000,-0.200000,0.700000,0.000000,0.000000,0.000000,1.000000)]
objects = [p.loadURDF("lego/lego.urdf", 1.000000,-0.200000,0.800000,0.000000,0.000000,0.000000,1.000000)]
objects = [p.loadURDF("lego/lego.urdf", 1.000000,-0.200000,0.900000,0.000000,0.000000,0.000000,1.000000)]
objects = p.loadSDF("gripper/wsg50_one_motor_gripper_new_free_base.sdf")
kuka_gripper = objects[0]
print ("kuka gripper=")
print(kuka_gripper)
p.resetBasePositionAndOrientation(kuka_gripper,[0.923103,-0.200000,1.250036],[-0.000000,0.964531,-0.000002,-0.263970])
jointPositions=[ 0.000000, -0.011130, -0.206421, 0.205143, -0.009999, 0.000000, -0.010055, 0.000000 ]
for jointIndex in range (p.getNumJoints(kuka_gripper)):
p.resetJointState(kuka_gripper,jointIndex,jointPositions[jointIndex])
p.setJointMotorControl2(kuka_gripper,jointIndex,p.POSITION_CONTROL,jointPositions[jointIndex],0)
kuka_cid = p.createConstraint(kuka, 6, kuka_gripper,0,p.JOINT_FIXED, [0,0,0], [0,0,0.05],[0,0,0])
objects = [p.loadURDF("jenga/jenga.urdf", 1.300000,-0.700000,0.750000,0.000000,0.707107,0.000000,0.707107)]
objects = [p.loadURDF("jenga/jenga.urdf", 1.200000,-0.700000,0.750000,0.000000,0.707107,0.000000,0.707107)]
objects = [p.loadURDF("jenga/jenga.urdf", 1.100000,-0.700000,0.750000,0.000000,0.707107,0.000000,0.707107)]
objects = [p.loadURDF("jenga/jenga.urdf", 1.000000,-0.700000,0.750000,0.000000,0.707107,0.000000,0.707107)]
objects = [p.loadURDF("jenga/jenga.urdf", 0.900000,-0.700000,0.750000,0.000000,0.707107,0.000000,0.707107)]
objects = [p.loadURDF("jenga/jenga.urdf", 0.800000,-0.700000,0.750000,0.000000,0.707107,0.000000,0.707107)]
objects = [p.loadURDF("table/table.urdf", 1.000000,-0.200000,0.000000,0.000000,0.000000,0.707107,0.707107)]
objects = [p.loadURDF("teddy_vhacd.urdf", 1.050000,-0.500000,0.700000,0.000000,0.000000,0.707107,0.707107)]
objects = [p.loadURDF("cube_small.urdf", 0.950000,-0.100000,0.700000,0.000000,0.000000,0.707107,0.707107)]
objects = [p.loadURDF("sphere_small.urdf", 0.850000,-0.400000,0.700000,0.000000,0.000000,0.707107,0.707107)]
objects = [p.loadURDF("duck_vhacd.urdf", 0.850000,-0.400000,0.900000,0.000000,0.000000,0.707107,0.707107)]
objects = p.loadSDF("kiva_shelf/model.sdf")
ob = objects[0]
p.resetBasePositionAndOrientation(ob,[0.000000,1.000000,1.204500],[0.000000,0.000000,0.000000,1.000000])
objects = [p.loadURDF("teddy_vhacd.urdf", -0.100000,0.600000,0.850000,0.000000,0.000000,0.000000,1.000000)]
objects = [p.loadURDF("sphere_small.urdf", -0.100000,0.955006,1.169706,0.633232,-0.000000,-0.000000,0.773962)]
objects = [p.loadURDF("cube_small.urdf", 0.300000,0.600000,0.850000,0.000000,0.000000,0.000000,1.000000)]
objects = [p.loadURDF("table_square/table_square.urdf", -1.000000,0.000000,0.000000,0.000000,0.000000,0.000000,1.000000)]
ob = objects[0]
jointPositions=[ 0.000000 ]
for jointIndex in range (p.getNumJoints(ob)):
p.resetJointState(ob,jointIndex,jointPositions[jointIndex])
objects = [p.loadURDF("husky/husky.urdf", 2.000000,-5.000000,1.000000,0.000000,0.000000,0.000000,1.000000)]
ob = objects[0]
jointPositions=[ 0.000000, 0.000000, 0.000000, 0.000000, 0.000000, 0.000000, 0.000000, 0.000000, 0.000000, 0.000000 ]
for jointIndex in range (p.getNumJoints(ob)):
p.resetJointState(ob,jointIndex,jointPositions[jointIndex])
p.configureDebugVisualizer(p.COV_ENABLE_RENDERING, 1)
p.setGravity(0.000000,0.000000,0.000000)
p.setGravity(0,0,-10)
##show this for 10 seconds
#now = time.time()
#while (time.time() < now+10):
# p.stepSimulation()
p.setRealTimeSimulation(1)
plugin = p.loadPlugin("e:/develop/bullet3/bin/pybullet_vrSyncPlugin_vs2010_x64_release.dll")
controllerId = 3
p.executePluginCommand(plugin ,"bla", [controllerId,pr2_cid, pr2_cid2,pr2_gripper],[50,3])
while (1):
#b = p.getJointState(pr2_gripper,2)[0]
#print("b = " + str(b))
#p.setJointMotorControl2(pr2_gripper, 0, p.POSITION_CONTROL, targetPosition=b, force=3)
p.setGravity(0,0,-10)
p.disconnect()

16
examples/pybullet/pybullet.c
View File

@@ -4971,7 +4971,7 @@ static PyObject* pybullet_getClosestPointData(PyObject* self, PyObject* args, Py
static PyObject* pybullet_changeUserConstraint(PyObject* self, PyObject* args, PyObject* keywds)
{
static char* kwlist[] = {"userConstraintUniqueId", "jointChildPivot", "jointChildFrameOrientation", "maxForce", "gearRatio", "gearAuxLink", "physicsClientId", NULL};
static char* kwlist[] = {"userConstraintUniqueId", "jointChildPivot", "jointChildFrameOrientation", "maxForce", "gearRatio", "gearAuxLink", "relativePositionTarget", "erp", "physicsClientId", NULL};
int userConstraintUniqueId = -1;
b3SharedMemoryCommandHandle commandHandle;
b3SharedMemoryStatusHandle statusHandle;
@@ -4985,7 +4985,9 @@ static PyObject* pybullet_changeUserConstraint(PyObject* self, PyObject* args, P
double jointChildFrameOrn[4];
double maxForce = -1;
double gearRatio = 0;
if (!PyArg_ParseTupleAndKeywords(args, keywds, "i|OOddii", kwlist, &userConstraintUniqueId, &jointChildPivotObj, &jointChildFrameOrnObj, &maxForce, &gearRatio, &gearAuxLink, &physicsClientId))
double relativePositionTarget=1e32;
double erp=-1;
if (!PyArg_ParseTupleAndKeywords(args, keywds, "i|OOddiddi", kwlist, &userConstraintUniqueId, &jointChildPivotObj, &jointChildFrameOrnObj, &maxForce, &gearRatio, &gearAuxLink, &relativePositionTarget, &erp, &physicsClientId))
{
return NULL;
}
@@ -5007,6 +5009,16 @@ static PyObject* pybullet_changeUserConstraint(PyObject* self, PyObject* args, P
{
b3InitChangeUserConstraintSetFrameInB(commandHandle, jointChildFrameOrn);
}
if (relativePositionTarget<1e10)
{
b3InitChangeUserConstraintSetRelativePositionTarget(commandHandle, relativePositionTarget);
}
if (erp>=0)
{
b3InitChangeUserConstraintSetERP(commandHandle, erp);
}
if (maxForce >= 0)
{
b3InitChangeUserConstraintSetMaxForce(commandHandle, maxForce);

2
src/BulletDynamics/Featherstone/btMultiBodyConstraint.h
View File

@@ -185,6 +185,8 @@ public:
virtual void setGearRatio(btScalar ratio) {}
virtual void setGearAuxLink(int gearAuxLink) {}
virtual void setRelativePositionTarget(btScalar relPosTarget){}
virtual void setErp(btScalar erp){}
};

19
src/BulletDynamics/Featherstone/btMultiBodyGearConstraint.cpp
View File

@@ -23,7 +23,9 @@ subject to the following restrictions:
btMultiBodyGearConstraint::btMultiBodyGearConstraint(btMultiBody* bodyA, int linkA, btMultiBody* bodyB, int linkB, const btVector3& pivotInA, const btVector3& pivotInB, const btMatrix3x3& frameInA, const btMatrix3x3& frameInB)
:btMultiBodyConstraint(bodyA,bodyB,linkA,linkB,1,false),
m_gearRatio(1),
m_gearAuxLink(-1)
m_gearAuxLink(-1),
m_erp(0),
m_relativePositionTarget(0)
{
}
@@ -107,9 +109,9 @@ void btMultiBodyGearConstraint::createConstraintRows(btMultiBodyConstraintArray&
jacobianA(0)[offsetA] = 1;
jacobianB(0)[offsetB] = m_gearRatio;
const btScalar posError = 0;
btScalar posError = 0;
const btVector3 dummy(0, 0, 0);
btScalar erp = infoGlobal.m_erp;
btScalar kp = 1;
btScalar kd = 1;
int numRows = getNumRows();
@@ -129,9 +131,14 @@ void btMultiBodyGearConstraint::createConstraintRows(btMultiBodyConstraintArray&
auxVel = m_bodyA->getJointVelMultiDof(m_gearAuxLink)[dof];
}
currentVelocity += auxVel;
//btScalar positionStabiliationTerm = erp*(m_desiredPosition-currentPosition)/infoGlobal.m_timeStep;
//btScalar velocityError = (m_desiredVelocity - currentVelocity);
if (m_erp!=0)
{
btScalar currentPositionA = m_bodyA->getJointPosMultiDof(m_linkA)[dof];
btScalar currentPositionB = m_gearRatio*m_bodyA->getJointPosMultiDof(m_linkB)[dof];
btScalar diff = currentPositionB+currentPositionA;
btScalar desiredPositionDiff = this->m_relativePositionTarget;
posError = -m_erp*(desiredPositionDiff - diff);
}
btScalar desiredRelativeVelocity = auxVel;

11
src/BulletDynamics/Featherstone/btMultiBodyGearConstraint.h
View File

@@ -32,6 +32,8 @@ protected:
btMatrix3x3 m_frameInB;
btScalar m_gearRatio;
int m_gearAuxLink;
btScalar m_erp;
btScalar m_relativePositionTarget;
public:
@@ -102,7 +104,14 @@ public:
{
m_gearAuxLink = gearAuxLink;
}
virtual void setRelativePositionTarget(btScalar relPosTarget)
{
m_relativePositionTarget = relPosTarget;
}
virtual void setErp(btScalar erp)
{
m_erp = erp;
}
};
#endif //BT_MULTIBODY_GEAR_CONSTRAINT_H