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add correct impulse matrix to multibody-deformable contact

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This commit is contained in:
Xuchen Han
2019-07-24 16:01:47 -07:00
parent 243b9fc8c7
commit 233a381e7c
14 changed files with 618 additions and 594 deletions
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46
examples/DeformableContact/DeformableContact.cpp
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@@ -69,10 +69,10 @@ public:
void resetCamera()
{
float dist = 15;
float dist = 30;
float pitch = -30;
float yaw = 100;
float targetPos[3] = {0, -3, 0};
float targetPos[3] = {0, -10, 0};
m_guiHelper->resetCamera(dist, yaw, pitch, targetPos[0], targetPos[1], targetPos[2]);
}
@@ -140,7 +140,7 @@ void DeformableContact::initPhysics()
btTransform groundTransform;
groundTransform.setIdentity();
groundTransform.setOrigin(btVector3(0, -40, 0));
groundTransform.setRotation(btQuaternion(btVector3(1, 0, 0), SIMD_PI * 0.1));
groundTransform.setRotation(btQuaternion(btVector3(1, 0, 0), SIMD_PI * 0.));
//We can also use DemoApplication::localCreateRigidBody, but for clarity it is provided here:
btScalar mass(0.);
@@ -163,16 +163,16 @@ void DeformableContact::initPhysics()
{
bool damping = false;
bool damping = true;
bool gyro = false;
int numLinks = 0;
bool spherical = true; //set it ot false -to use 1DoF hinges instead of 3DoF sphericals
int numLinks = 4;
bool spherical = false; //set it ot false -to use 1DoF hinges instead of 3DoF sphericals
bool canSleep = false;
bool selfCollide = true;
btVector3 linkHalfExtents(1, 1, 1);
btVector3 baseHalfExtents(1, 1, 1);
btMultiBody* mbC = createFeatherstoneMultiBody_testMultiDof(m_dynamicsWorld, numLinks, btVector3(0.f, 2.f,0.f), linkHalfExtents, baseHalfExtents, spherical, g_floatingBase);
btMultiBody* mbC = createFeatherstoneMultiBody_testMultiDof(m_dynamicsWorld, numLinks, btVector3(0.f, 10.f,0.f), linkHalfExtents, baseHalfExtents, spherical, g_floatingBase);
mbC->setCanSleep(canSleep);
mbC->setHasSelfCollision(selfCollide);
@@ -180,13 +180,13 @@ void DeformableContact::initPhysics()
//
if (!damping)
{
mbC->setLinearDamping(0.f);
mbC->setAngularDamping(0.f);
mbC->setLinearDamping(0.0f);
mbC->setAngularDamping(0.0f);
}
else
{
mbC->setLinearDamping(0.1f);
mbC->setAngularDamping(0.9f);
mbC->setLinearDamping(0.04f);
mbC->setAngularDamping(0.04f);
}
if (numLinks > 0)
@@ -209,22 +209,24 @@ void DeformableContact::initPhysics()
// create a patch of cloth
{
btScalar h = 0;
const btScalar s = 4;
btSoftBody* psb = btSoftBodyHelpers::CreatePatch(getDeformableDynamicsWorld()->getWorldInfo(), btVector3(-s, 0, -s),
btVector3(+s, 0, -s),
btVector3(-s, 0, +s),
btVector3(+s, 0, +s),
// 20,20,
3,3,
btSoftBody* psb = btSoftBodyHelpers::CreatePatch(getDeformableDynamicsWorld()->getWorldInfo(), btVector3(-s, h, -s),
btVector3(+s, h, -s),
btVector3(-s, h, +s),
btVector3(+s, h, +s),
20,20,
// 3,3,
1 + 2 + 4 + 8, true);
psb->getCollisionShape()->setMargin(0.25);
psb->generateBendingConstraints(2);
psb->setTotalMass(.5);
psb->setTotalMass(5);
psb->setSpringStiffness(2);
psb->setDampingCoefficient(0.01);
psb->m_cfg.kKHR = 1; // collision hardness with kinematic objects
psb->m_cfg.kCHR = 1; // collision hardness with rigid body
psb->m_cfg.kDF = 0;
psb->m_cfg.kDF = .1;
getDeformableDynamicsWorld()->addSoftBody(psb);
}
@@ -271,7 +273,7 @@ void DeformableContact::exitPhysics()
void DeformableContact::stepSimulation(float deltaTime)
{
// getDeformableDynamicsWorld()->getMultiBodyDynamicsWorld()->stepSimulation(deltaTime);
m_dynamicsWorld->stepSimulation(deltaTime, 4, 1./240.);
m_dynamicsWorld->stepSimulation(deltaTime, 5, 1./250.);
}
@@ -279,7 +281,7 @@ btMultiBody* DeformableContact::createFeatherstoneMultiBody_testMultiDof(btMulti
{
//init the base
btVector3 baseInertiaDiag(0.f, 0.f, 0.f);
float baseMass = .05f;
float baseMass = .1f;
if (baseMass)
{
@@ -300,7 +302,7 @@ btMultiBody* DeformableContact::createFeatherstoneMultiBody_testMultiDof(btMulti
//init the links
btVector3 hingeJointAxis(1, 0, 0);
float linkMass = .05f;
float linkMass = .1f;
btVector3 linkInertiaDiag(0.f, 0.f, 0.f);
btCollisionShape* pTempBox = new btBoxShape(btVector3(linkHalfExtents[0], linkHalfExtents[1], linkHalfExtents[2]));

2
examples/ExampleBrowser/ExampleEntries.cpp
View File

@@ -50,6 +50,7 @@
#include "../DeformableDemo/DeformableDemo.h"
#include "../Pinch/Pinch.h"
#include "../DeformableContact/DeformableContact.h"
#include "../MultiBodyBaseline/MultiBodyBaseline.h"
#include "../VolumetricDeformable/VolumetricDeformable.h"
#include "../SharedMemory/PhysicsServerExampleBullet2.h"
#include "../SharedMemory/PhysicsServerExample.h"
@@ -126,6 +127,7 @@ static ExampleEntry gDefaultExamples[] =
ExampleEntry(0, "Grasp Deformable Cube", "Grasping test", PinchCreateFunc),
ExampleEntry(0, "Volumetric Deformable Objects", "Volumetric Deformable test", VolumetricDeformableCreateFunc),
ExampleEntry(0, "Deformable-MultiBody Contact", "MultiBody and Deformable contact", DeformableContactCreateFunc),
ExampleEntry(0, "MultiBody Baseline", "MultiBody Baseline", MultiBodyBaselineCreateFunc),
ExampleEntry(1, "Constraints", "Show the use of the various constraints in Bullet. Press the L key to visualize the constraint limits. Press the C key to visualize the constraint frames.",
AllConstraintCreateFunc),

358
examples/MultiBodyBaseline/MultiBodyBaseline.cpp Normal file
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@@ -0,0 +1,358 @@
/*
Bullet Continuous Collision Detection and Physics Library
Copyright (c) 2003-2006 Erwin Coumans http://continuousphysics.com/Bullet/
This software is provided 'as-is', without any express or implied warranty.
In no event will the authors be held liable for any damages arising from the use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it freely,
subject to the following restrictions:
1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
*/
///create 125 (5x5x5) dynamic object
#define ARRAY_SIZE_X 5
#define ARRAY_SIZE_Y 5
#define ARRAY_SIZE_Z 5
//maximum number of objects (and allow user to shoot additional boxes)
#define MAX_PROXIES (ARRAY_SIZE_X * ARRAY_SIZE_Y * ARRAY_SIZE_Z + 1024)
///scaling of the objects (0.1 = 20 centimeter boxes )
#define SCALING 1.
#define START_POS_X -5
#define START_POS_Y -5
#define START_POS_Z -3
#include "MultiBodyBaseline.h"
///btBulletDynamicsCommon.h is the main Bullet include file, contains most common include files.
#include "btBulletDynamicsCommon.h"
#include "BulletSoftBody/btDeformableRigidDynamicsWorld.h"
#include "BulletSoftBody/btSoftBody.h"
#include "BulletSoftBody/btSoftBodyHelpers.h"
#include "BulletSoftBody/btDeformableBodySolver.h"
#include "BulletSoftBody/btSoftBodyRigidBodyCollisionConfiguration.h"
#include "BulletDynamics/Featherstone/btMultiBodyConstraintSolver.h"
#include <stdio.h> //printf debugging
#include "../CommonInterfaces/CommonRigidBodyBase.h"
#include "../Utils/b3ResourcePath.h"
#include "../SoftDemo/BunnyMesh.h"
#include "BulletDynamics/Featherstone/btMultiBodyLinkCollider.h"
#include "BulletDynamics/Featherstone/btMultiBodyJointFeedback.h"
#include "../CommonInterfaces/CommonMultiBodyBase.h"
#include "../Utils/b3ResourcePath.h"
///The MultiBodyBaseline demo deformable bodies self-collision
static bool g_floatingBase = true;
static float friction = 1.;
class MultiBodyBaseline : public CommonMultiBodyBase
{
btMultiBody* m_multiBody;
btAlignedObjectArray<btMultiBodyJointFeedback*> m_jointFeedbacks;
public:
MultiBodyBaseline(struct GUIHelperInterface* helper)
: CommonMultiBodyBase(helper)
{
}
virtual ~MultiBodyBaseline()
{
}
void initPhysics();
void exitPhysics();
void resetCamera()
{
float dist = 30;
float pitch = -30;
float yaw = 100;
float targetPos[3] = {0, -10, 0};
m_guiHelper->resetCamera(dist, yaw, pitch, targetPos[0], targetPos[1], targetPos[2]);
}
virtual void stepSimulation(float deltaTime);
btMultiBody* createFeatherstoneMultiBody_testMultiDof(class btMultiBodyDynamicsWorld* world, int numLinks, const btVector3& basePosition, const btVector3& baseHalfExtents, const btVector3& linkHalfExtents, bool spherical = false, bool floating = false);
void addColliders_testMultiDof(btMultiBody* pMultiBody, btMultiBodyDynamicsWorld* pWorld, const btVector3& baseHalfExtents, const btVector3& linkHalfExtents);
};
void MultiBodyBaseline::initPhysics()
{
m_guiHelper->setUpAxis(1);
///collision configuration contains default setup for memory, collision setup
m_collisionConfiguration = new btSoftBodyRigidBodyCollisionConfiguration();
///use the default collision dispatcher. For parallel processing you can use a diffent dispatcher (see Extras/BulletMultiThreaded)
m_dispatcher = new btCollisionDispatcher(m_collisionConfiguration);
m_broadphase = new btDbvtBroadphase();
btMultiBodyConstraintSolver* sol;
sol = new btMultiBodyConstraintSolver;
m_solver = sol;
btMultiBodyDynamicsWorld* world = new btMultiBodyDynamicsWorld(m_dispatcher, m_broadphase, sol, m_collisionConfiguration);
m_dynamicsWorld = world;
// m_dynamicsWorld->setDebugDrawer(&gDebugDraw);
m_guiHelper->createPhysicsDebugDrawer(m_dynamicsWorld);
m_dynamicsWorld->setGravity(btVector3(0, -10, 0));
{
///create a ground
btCollisionShape* groundShape = new btBoxShape(btVector3(btScalar(150.), btScalar(25.), btScalar(150.)));
m_collisionShapes.push_back(groundShape);
btTransform groundTransform;
groundTransform.setIdentity();
groundTransform.setOrigin(btVector3(0, -40, 0));
groundTransform.setRotation(btQuaternion(btVector3(1, 0, 0), SIMD_PI * 0.));
//We can also use DemoApplication::localCreateRigidBody, but for clarity it is provided here:
btScalar mass(0.);
//rigidbody is dynamic if and only if mass is non zero, otherwise static
bool isDynamic = (mass != 0.f);
btVector3 localInertia(0, 0, 0);
if (isDynamic)
groundShape->calculateLocalInertia(mass, localInertia);
//using motionstate is recommended, it provides interpolation capabilities, and only synchronizes 'active' objects
btDefaultMotionState* myMotionState = new btDefaultMotionState(groundTransform);
btRigidBody::btRigidBodyConstructionInfo rbInfo(mass, myMotionState, groundShape, localInertia);
btRigidBody* body = new btRigidBody(rbInfo);
body->setFriction(0.5);
//add the ground to the dynamics world
m_dynamicsWorld->addRigidBody(body,1,1+2);
}
{
bool damping = true;
bool gyro = false;
int numLinks = 4;
bool spherical = false; //set it ot false -to use 1DoF hinges instead of 3DoF sphericals
bool canSleep = false;
bool selfCollide = true;
btVector3 linkHalfExtents(1, 1, 1);
btVector3 baseHalfExtents(1, 1, 1);
btMultiBody* mbC = createFeatherstoneMultiBody_testMultiDof(m_dynamicsWorld, numLinks, btVector3(0.f, 10.f,0.f), linkHalfExtents, baseHalfExtents, spherical, g_floatingBase);
mbC->setCanSleep(canSleep);
mbC->setHasSelfCollision(selfCollide);
mbC->setUseGyroTerm(gyro);
//
if (!damping)
{
mbC->setLinearDamping(0.0f);
mbC->setAngularDamping(0.0f);
}
else
{
mbC->setLinearDamping(0.04f);
mbC->setAngularDamping(0.04f);
}
if (numLinks > 0)
{
btScalar q0 = 0.f * SIMD_PI / 180.f;
if (!spherical)
{
mbC->setJointPosMultiDof(0, &q0);
}
else
{
btQuaternion quat0(btVector3(1, 1, 0).normalized(), q0);
quat0.normalize();
mbC->setJointPosMultiDof(0, quat0);
}
}
///
addColliders_testMultiDof(mbC, m_dynamicsWorld, baseHalfExtents, linkHalfExtents);
}
m_guiHelper->autogenerateGraphicsObjects(m_dynamicsWorld);
}
void MultiBodyBaseline::exitPhysics()
{
//cleanup in the reverse order of creation/initialization
//remove the rigidbodies from the dynamics world and delete them
int i;
for (i = m_dynamicsWorld->getNumCollisionObjects() - 1; i >= 0; i--)
{
btCollisionObject* obj = m_dynamicsWorld->getCollisionObjectArray()[i];
btRigidBody* body = btRigidBody::upcast(obj);
if (body && body->getMotionState())
{
delete body->getMotionState();
}
m_dynamicsWorld->removeCollisionObject(obj);
delete obj;
}
//delete collision shapes
for (int j = 0; j < m_collisionShapes.size(); j++)
{
btCollisionShape* shape = m_collisionShapes[j];
delete shape;
}
m_collisionShapes.clear();
delete m_dynamicsWorld;
delete m_solver;
delete m_broadphase;
delete m_dispatcher;
delete m_collisionConfiguration;
}
void MultiBodyBaseline::stepSimulation(float deltaTime)
{
// getDeformableDynamicsWorld()->getMultiBodyDynamicsWorld()->stepSimulation(deltaTime);
m_dynamicsWorld->stepSimulation(deltaTime, 5, 1./250.);
}
btMultiBody* MultiBodyBaseline::createFeatherstoneMultiBody_testMultiDof(btMultiBodyDynamicsWorld* pWorld, int numLinks, const btVector3& basePosition, const btVector3& baseHalfExtents, const btVector3& linkHalfExtents, bool spherical, bool floating)
{
//init the base
btVector3 baseInertiaDiag(0.f, 0.f, 0.f);
float baseMass = .1f;
if (baseMass)
{
btCollisionShape* pTempBox = new btBoxShape(btVector3(baseHalfExtents[0], baseHalfExtents[1], baseHalfExtents[2]));
pTempBox->calculateLocalInertia(baseMass, baseInertiaDiag);
delete pTempBox;
}
bool canSleep = false;
btMultiBody* pMultiBody = new btMultiBody(numLinks, baseMass, baseInertiaDiag, !floating, canSleep);
btQuaternion baseOriQuat(0.f, 0.f, 0.f, 1.f);
pMultiBody->setBasePos(basePosition);
pMultiBody->setWorldToBaseRot(baseOriQuat);
btVector3 vel(0, 0, 0);
// pMultiBody->setBaseVel(vel);
//init the links
btVector3 hingeJointAxis(1, 0, 0);
float linkMass = .1f;
btVector3 linkInertiaDiag(0.f, 0.f, 0.f);
btCollisionShape* pTempBox = new btBoxShape(btVector3(linkHalfExtents[0], linkHalfExtents[1], linkHalfExtents[2]));
pTempBox->calculateLocalInertia(linkMass, linkInertiaDiag);
delete pTempBox;
//y-axis assumed up
btVector3 parentComToCurrentCom(0, -linkHalfExtents[1] * 2.f, 0); //par body's COM to cur body's COM offset
btVector3 currentPivotToCurrentCom(0, -linkHalfExtents[1], 0); //cur body's COM to cur body's PIV offset
btVector3 parentComToCurrentPivot = parentComToCurrentCom - currentPivotToCurrentCom; //par body's COM to cur body's PIV offset
//////
btScalar q0 = 0.f * SIMD_PI / 180.f;
btQuaternion quat0(btVector3(0, 1, 0).normalized(), q0);
quat0.normalize();
/////
for (int i = 0; i < numLinks; ++i)
{
if (!spherical)
pMultiBody->setupRevolute(i, linkMass, linkInertiaDiag, i - 1, btQuaternion(0.f, 0.f, 0.f, 1.f), hingeJointAxis, parentComToCurrentPivot, currentPivotToCurrentCom, true);
else
//pMultiBody->setupPlanar(i, linkMass, linkInertiaDiag, i - 1, btQuaternion(0.f, 0.f, 0.f, 1.f)/*quat0*/, btVector3(1, 0, 0), parentComToCurrentPivot*2, false);
pMultiBody->setupSpherical(i, linkMass, linkInertiaDiag, i - 1, btQuaternion(0.f, 0.f, 0.f, 1.f), parentComToCurrentPivot, currentPivotToCurrentCom, true);
}
pMultiBody->finalizeMultiDof();
///
pWorld->addMultiBody(pMultiBody);
///
return pMultiBody;
}
void MultiBodyBaseline::addColliders_testMultiDof(btMultiBody* pMultiBody, btMultiBodyDynamicsWorld* pWorld, const btVector3& baseHalfExtents, const btVector3& linkHalfExtents)
{
btAlignedObjectArray<btQuaternion> world_to_local;
world_to_local.resize(pMultiBody->getNumLinks() + 1);
btAlignedObjectArray<btVector3> local_origin;
local_origin.resize(pMultiBody->getNumLinks() + 1);
world_to_local[0] = pMultiBody->getWorldToBaseRot();
local_origin[0] = pMultiBody->getBasePos();
{
// float pos[4]={local_origin[0].x(),local_origin[0].y(),local_origin[0].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()};
if (1)
{
btCollisionShape* box = new btBoxShape(baseHalfExtents);
btMultiBodyLinkCollider* col = new btMultiBodyLinkCollider(pMultiBody, -1);
col->setCollisionShape(box);
btTransform tr;
tr.setIdentity();
tr.setOrigin(local_origin[0]);
tr.setRotation(btQuaternion(quat[0], quat[1], quat[2], quat[3]));
col->setWorldTransform(tr);
pWorld->addCollisionObject(col, 2, 1 + 2);
col->setFriction(friction);
pMultiBody->setBaseCollider(col);
}
}
for (int i = 0; i < pMultiBody->getNumLinks(); ++i)
{
const int parent = pMultiBody->getParent(i);
world_to_local[i + 1] = pMultiBody->getParentToLocalRot(i) * world_to_local[parent + 1];
local_origin[i + 1] = local_origin[parent + 1] + (quatRotate(world_to_local[i + 1].inverse(), pMultiBody->getRVector(i)));
}
for (int i = 0; i < pMultiBody->getNumLinks(); ++i)
{
btVector3 posr = local_origin[i + 1];
// float pos[4]={posr.x(),posr.y(),posr.z(),1};
btScalar quat[4] = {-world_to_local[i + 1].x(), -world_to_local[i + 1].y(), -world_to_local[i + 1].z(), world_to_local[i + 1].w()};
btCollisionShape* box = new btBoxShape(linkHalfExtents);
btMultiBodyLinkCollider* col = new btMultiBodyLinkCollider(pMultiBody, i);
col->setCollisionShape(box);
btTransform tr;
tr.setIdentity();
tr.setOrigin(posr);
tr.setRotation(btQuaternion(quat[0], quat[1], quat[2], quat[3]));
col->setWorldTransform(tr);
col->setFriction(friction);
pWorld->addCollisionObject(col, 2, 1 + 2);
pMultiBody->getLink(i).m_collider = col;
}
}
class CommonExampleInterface* MultiBodyBaselineCreateFunc(struct CommonExampleOptions& options)
{
return new MultiBodyBaseline(options.m_guiHelper);
}

20
examples/MultiBodyBaseline/MultiBodyBaseline.h Normal file
View File

@@ -0,0 +1,20 @@
/*
Bullet Continuous Collision Detection and Physics Library
Copyright (c) 2003-2006 Erwin Coumans http://continuousphysics.com/Bullet/
This software is provided 'as-is', without any express or implied warranty.
In no event will the authors be held liable for any damages arising from the use of this software.
Permission is granted to anyone to use this software for any purpose,
including commercial applications, and to alter it and redistribute it freely,
subject to the following restrictions:
1. The origin of this software must not be misrepresented; you must not claim that you wrote the original software. If you use this software in a product, an acknowledgment in the product documentation would be appreciated but is not required.
2. Altered source versions must be plainly marked as such, and must not be misrepresented as being the original software.
3. This notice may not be removed or altered from any source distribution.
*/
#ifndef _MULTIBODY_BASELINE_H
#define _MULTIBODY_BASELINE_H
class CommonExampleInterface* MultiBodyBaselineCreateFunc(struct CommonExampleOptions& options);
#endif //_MULTIBODY_BASELINE_H

4
examples/VolumetricDeformable/VolumetricDeformable.cpp
View File

@@ -77,8 +77,8 @@ public:
void stepSimulation(float deltaTime)
{
//use a smaller internal timestep, there are stability issues
float internalTimeStep = 1. / 480.f;
m_dynamicsWorld->stepSimulation(deltaTime, 8, internalTimeStep);
float internalTimeStep = 1. / 240.f;
m_dynamicsWorld->stepSimulation(deltaTime, 4, internalTimeStep);
}
void createStaticBox(const btVector3& halfEdge, const btVector3& translation)