implement friction anchors, position friction correction, disabled by default. Use colObj->setCollisionFlag(flag | CF_HAS_FRICTION_ANCHOR); See test/RobotClientAPI/SlopeFrictionMain.cpp. In URDF or SDF, add <friction_anchor/> in <contact> section of <link> to enable.
PhysicsServer: properly restore old activation state after releasing picked object
btMultiBodyConstraintSolver: disable flip/flop of contact/friction constraint solving by default (it breaks some internal flaky unit tests)
added test urdf files for minitaur with all fixed joints, or fixed knees.
added some stiffness/damping to minitaur legs (testing)
tiny_obj_loader, don't crash on invalid texture coordinates
btMultiBodyConstraintSolver: sweep back and forward to reduce asymmetry
[pybullet] updated pybullet_quickstartguide.pdf
Fail clearly (assert, return BT_INFINITY) if link index is out of range for btMultiBody methods localPosToWorld,worldPosToLocal,localDirToWorld,worldDirToLocal.
pybullet getConstraintInfo
Fix warnings due to Mac OSX 10.12 upgrade (with backward compatibility)
fixed some more warnings
added alignment macros to some classes
btPersistentManifold from 128 to 16 bytes aligned
prepare command to select collision filter mode (SIM_PARAM_UPDATE_COLLISION_FILTER_MODE)
(for example solverInfo().m_leastSquaresResidualThreshold = 1e-7 and use large m_numSolverIterations
disable sphere-sphere contact cache, it is buggy (some contact point stay in the cache, when sphere penetrates more than total margins)
tweak some gpu demo settings
allow 'useMaximalCoordinates' and 'useFixedBase' in pybullet.loadURDF.
enable split impulse for btRigidBody, even in btMultiBodyDynamicsWorld.
allow initialization of velocity and apply force for btRigidBody in pybullet/shared memory API.
process contact parameters in URDF also for btRigidBody (friction, restitution etc)
add pybullet.setPhysicsEngineParameter with numSolverIterations, useSplitImpulse etc.
use btAssert to detect 0 determinant in btMatrix3x3 inverse
Remove obsolete comment in PosixSharedMemory, the Windows shared memory implementation was done over a year ago
rolling friction -> only along the normal, until we have separate rolling friction coefficients on normal and non-normal directions
Don't teleport with grasping controller (VR)
Tune VR grasping a bit.
returns a pylist of contact points. Each point has the following data:
0 int m_contactFlags;//unused for now
1 int m_bodyUniqueIdA;
2 int m_bodyUniqueIdB;
3 int m_linkIndexA;
4 int m_linkIndexB;
5-6-7 double m_positionOnAInWS[3];//contact point location on object A, in world space coordinates
8-9-10 double m_positionOnBInWS[3];//contact point location on object A, in world space coordinates
11-12-13 double m_contactNormalOnBInWS[3];//the separating contact normal, pointing from object B towards object A
14 double m_contactDistance;//negative number is penetration, positive is distance.
15 double m_normalForce;
Fix issue in contact/friction between btMultibody and btRigidBody (external force/torque of btRigidBody was not taken into account during contact/friction setup)
Allow 0.1 mm slop in contact, to avoid loosing contact. Todo: allow contacts with positive distance in multibody solver.
causing serialization issue in URDF/SDF loading in double-precision mode on Windows 32bit.
(it was fine on Mac/Linux 64bit)
bump serialization version to 2.85, as we change the file format
fix in name clash in makesdna.cpp -> intptr_t is already defined.
Uses Kuka IIWA model description and 4 methods:
Selectively Damped Least Squares,Damped Least Squares,
Jacobi Transpose, Jacobi Pseudo Inverse
Tweak some PD values in Inverse Dynamics example and Robot example.
Added demos for rigid and multi body soft (compliant) contact.
Will also add simplified Hertz compliant contact, by dynamically modifying the ERP/CFM to mimic a non-linear spring.
Note that btManifoldPoint is growing too big, we need to implement proper contact constraints derived from btTypedConstraint.
CFM for contacts use world CFM value by default, and can override with custom CFM value using the
BT_CONTACT_FLAG_HAS_CONTACT_CFM stored in m_contactPointFlags.
Boolean m_lateralFrictionInitialized is replaced 'BT_CONTACT_FLAG_LATERAL_FRICTION_INITIALIZED' flag stored in int m_contactPointFlags in btManifoldPoint.
Enable successive over-relaxation parameter (SOR) for contacts. btMLCPSolver uses global CFM.
In one of the next commits, contact softness will be enabled btMultiBody contacts.
Also need to review use of CFM in btMLCPSolvers (only world CFM is used at the moment)
Parse and use colors from URDF file (single rgba color per link, not per visual)
Rename btMultiBody 'stepVelocities' to 'computeAccelerationsArticulatedBodyAlgorithmMultiDof'
btHashMap, add const Value* operator[]
remove a few more obsolete btMultiBody methods (on the non-multi-dof path)
fix spelling typo in fillConstraintJacobianMultiDof (fil -> fill)
Add mention to Jakub Stepien for his work on btMultiBody