Search found 4223 matches

by Erwin Coumans
Fri Nov 13, 2020 10:17 pm
Forum: PyBullet Support and Feedback
Topic: Doubts about setJointMotorControl2 implementation
Replies: 1
Views: 558

Re: Doubts about setJointMotorControl2 implementation

PyBullet setJointMotorControl2 also has regular PD control. When using velocity control, it is up to the maximum force how fast the target is reached.
by Erwin Coumans
Fri Nov 13, 2020 10:15 pm
Forum: PyBullet Support and Feedback
Topic: Malloc error during creatiion of a soft body from a .vtk
Replies: 4
Views: 629

Re: Malloc error during creatiion of a soft body from a .vtk

It could be the vtk file, can you attach (zipped) cube1.vtk?
by Erwin Coumans
Wed Oct 14, 2020 3:08 am
Forum: PyBullet Support and Feedback
Topic: maxVelocity in setJointMotorControlArray
Replies: 1
Views: 758

Re: maxVelocity in setJointMotorControlArray

It hasn't been added yet, it can be done. Perhaps file an issue request on github.
by Erwin Coumans
Wed Oct 14, 2020 3:05 am
Forum: PyBullet Support and Feedback
Topic: Question Regarding stepSimulation()
Replies: 1
Views: 402

Re: Question Regarding stepSimulation()

The position is achieved taken all constraints into account, including the maximum force and joint limits, contact, friction etc.

There is a maxVelocity argument to clamp the maximum velocity. Alternatively, keep the max force low.
You can also use classical PD control.
by Erwin Coumans
Thu Sep 17, 2020 2:22 am
Forum: Research and development discussion about Collision Detection and Physics Simulation
Topic: Baraff/Witkin's integration matrix not positive: what to do?
Replies: 14
Views: 6441

Re: Baraff/Witkin's integration matrix not positive: what to do?

Finally, it took 11 years but it was worth waiting: a new paper by Theodore Kim addresses the problem, and one of the references points to this forum thread. See http://www.tkim.graphics/FEMBW or https://twitter.com/_TheodoreKim/status ... 0997393409
by Erwin Coumans
Thu Aug 20, 2020 3:03 am
Forum: PyBullet Support and Feedback
Topic: How does one lock rotation on one axis?
Replies: 1
Views: 905

Re: How does one lock rotation on one axis?

This forum is for PyBullet not panda.bullet
by Erwin Coumans
Thu Aug 20, 2020 3:02 am
Forum: PyBullet Support and Feedback
Topic: Simulate a rope for ball in the cup task
Replies: 1
Views: 1057

Re: Simulate a rope for ball in the cup task

You can use maximal coordinates for the rope, it is likely more stable. (loadURDF(..., useMaximalCoordinates=True)
Or use deformable bodies, see https://github.com/bulletphysics/bullet ... _anchor.py
by Erwin Coumans
Thu Aug 20, 2020 3:00 am
Forum: PyBullet Support and Feedback
Topic: Using Z Axis down in the debug visualizer
Replies: 1
Views: 756

Re: Using Z Axis down in the debug visualizer

It is unfortunately not possible.
by Erwin Coumans
Thu Aug 20, 2020 2:59 am
Forum: PyBullet Support and Feedback
Topic: Read .bullet file to plot
Replies: 1
Views: 608

Re: Read .bullet file to plot

Try using https://github.com/bulletphysics/bullet3/tree/master/Extras/Serialize/ReadBulletSample or alternatively, save the joints using another mechanism, for example save manually or using startStateLogging, for example using STATE_LOGGING_MINITAUR (see the PyBullet Quickstart Guide) There are Pyt...
by Erwin Coumans
Wed Jul 08, 2020 5:02 pm
Forum: PyBullet Support and Feedback
Topic: HopperMuJoCoEnv
Replies: 1
Views: 696

Re: HopperMuJoCoEnv

PyBullet ships with HopperBulletEnv-v0, and other environments as listed here:

https://github.com/bulletphysics/bullet ... _init__.py

This forum is for PyBullet, if you want MuJoCo or Benelot's environments, try visiting another forum.
by Erwin Coumans
Wed Jul 08, 2020 12:05 am
Forum: PyBullet Support and Feedback
Topic: setJointMotorControl2 won't assign correct force value to certain joints
Replies: 5
Views: 1675

Re: setJointMotorControl2 won't assign correct force value to certain joints

Don't enable 'realtime' simulation, but stepSimulation instead, when applying forces like this. Also, best to keep using a small time step (1./240. is default), not 1 second. Watch the various examples/gym environments, for example https://github.com/bulletphysics/bullet3/tree/master/examples/pybull...
by Erwin Coumans
Mon Jun 29, 2020 11:08 pm
Forum: PyBullet Support and Feedback
Topic: error: Not connected to physics server
Replies: 2
Views: 999

Re: error: Not connected to physics server

We don't support those envs. Please try using the envs included with pybullet_envs (after pip install pybullet --upgrade --user) HalfCheetahBulletEnv-v0 etc. Here is a list: https://github.com/pat-coady/trpo HumanoidDeepMimicBulletEnv-v1 CartPoleBulletEnv-v1 MinitaurBulletEnv-v0 MinitaurBulletDuckEn...
by Erwin Coumans
Fri Jun 19, 2020 4:09 pm
Forum: PyBullet Support and Feedback
Topic: [SOLVED in pybullet 2.8.2] Simple two-link URDF applyExternalForce unexpected response
Replies: 4
Views: 1566

Re: Simple two-link URDF applyExternalForce unexpected response

Ah, I disabled the velocity/position motors by setting the force to zero. You can certainly leave the motors enabled, with a force of your choice to model joint friction or other effects such as springyness. I was assuming metric units (meter, seconds etc). If you are using different units, you need...