Search found 4180 matches

by Erwin Coumans
Thu Nov 01, 2018 1:24 pm
Forum: General Bullet Physics Support and Feedback
Topic: Spatial query of the world
Replies: 4
Views: 584

Re: Spatial query of the world

Fastest is broadphase->aabbTest(), but based on aabb bounding volumes of objects.

Precise is collisionWorld->contactTest(). If you use a sphere (btSphereShape), it will be similar to the OpenDE test.

The query btCollisionObject in contactTest isn't part of the world.
by Erwin Coumans
Thu Nov 01, 2018 1:09 pm
Forum: General Bullet Physics Support and Feedback
Topic: Dramatic slow down when using SAT convex.
Replies: 5
Views: 653

Re: Dramatic slow down when using SAT convex.

Our SAT is not used by default and not well optimized. The default settings using GJK+EPA+ incremental persistent contact manifold should work really well, especially at 240hz. We accumulate up to 4 points, so there won't be single contacts for long. >> When not using SAT, I also see a slow down, sl...
by Erwin Coumans
Sun Oct 28, 2018 1:56 am
Forum: General Bullet Physics Support and Feedback
Topic: multibody m_appliedImpulse zero
Replies: 2
Views: 461

Re: multibody m_appliedImpulse zero

The applied impulse should be available in the post-tick callback, if you enable if SOLVER_USE_WARMSTARTING in the solver info.

In PyBullet that is how we provide the contact normal and lateral friction forces and they are non-zero.
by Erwin Coumans
Wed Oct 17, 2018 2:09 am
Forum: PyBullet Support and Feedback
Topic: pip install failure
Replies: 3
Views: 760

Re: pip install failure

It should be fixed now. Try using version 2.3.2 or later

pip install --no-cache-dir pybullet --user

Thanks for the report!
by Erwin Coumans
Mon Oct 15, 2018 11:04 pm
Forum: PyBullet Support and Feedback
Topic: How to Control Camera view of the GUI
Replies: 3
Views: 1324

Re: How to Control Camera view of the GUI

Use the <CTRL> or <ALT> key in combination with mouse buttons+dragging the mouse.
Also you can use touch pad sliding to zoom in/out.
by Erwin Coumans
Mon Oct 15, 2018 11:03 pm
Forum: PyBullet Support and Feedback
Topic: Defining a Kinematic Object
Replies: 2
Views: 689

Re: Defining a Kinematic Object

It is recommended to use a fixed constraint and move the parent location of the fixed constraint. (Kinematic bodies are not supported in PyBullet) relativeChildPosition=[0,0,1] relativeChildOrientation=[0,0,0,1] hand_cid = p.createConstraint(hand,-1,-1,-1,p.JOINT_FIXED,[0,0,0],[0,0,0],relativeChildP...
by Erwin Coumans
Mon Oct 15, 2018 10:59 pm
Forum: PyBullet Support and Feedback
Topic: build failure for pybullet project in VS2017
Replies: 2
Views: 646

Re: build failure for pybullet project in VS2017

It is best to use 'pip install pybullet' to compile PyBullet. Edit the build file and remove the --enable_pybullet and re-create the project files. Compiling the Debug version of PyBullet is much mode work, since most Python distributions only ship with Release/optimized builds. Find/install some Py...
by Erwin Coumans
Mon Oct 15, 2018 9:12 pm
Forum: PyBullet Support and Feedback
Topic: Car Simulation for Radar
Replies: 6
Views: 1296

Re: Car Simulation for Radar

Create a dummy link (replace planeLink with parent link name, joint origin xyz is in local parent link coordinates): <link name="dummy"> <inertial> <mass value="0"/> <inertia ixx="1.0" ixy="0.0" ixz="0.0" iyy="1.0" iyz="0.0" izz="1.0"/> </inertial> </link> <joint name="base_to_dummy" type="fixed"> <...
by Erwin Coumans
Sun Oct 07, 2018 2:01 pm
Forum: General Bullet Physics Support and Feedback
Topic: Strange behavior of rigid bodies (video) C++
Replies: 2
Views: 590

Re: Strange behavior of rigid bodies (video) C++

getRotation returns a quaternion, not Euler angles. There are functions to convert quat to eul.
by Erwin Coumans
Fri Oct 05, 2018 1:43 am
Forum: PyBullet Support and Feedback
Topic: PyBullet multi-physics engine support
Replies: 1
Views: 610

Re: PyBullet multi-physics engine support

There is no timeline for it. The feature is mainly for benchmarking purposes, I assume PyBullet users want to use Bullet instead of DART or MuJoCo. I got the MuJoCo very basic test working in PyBullet loading a basic MJCF file etc.
by Erwin Coumans
Fri Oct 05, 2018 1:42 am
Forum: PyBullet Support and Feedback
Topic: Checkbox/radio button using PyBullet
Replies: 1
Views: 486

Re: Checkbox/radio button using PyBullet

>>Was wondering if there are methods for adding radio buttons or checkboxes The underlying infrastructure has check boxes, booleans and text etc, but we only exposed sliders so far. Perhaps submit a issue request in github issue tracker? >> addUserData Not much, I would check the userData.py example...
by Erwin Coumans
Fri Oct 05, 2018 1:31 am
Forum: PyBullet Support and Feedback
Topic: Saving and restoring full state?
Replies: 3
Views: 1369

Re: Saving and restoring full state?

Where is 'envStepCounter'? If it is in Python, just reset it there.
by Erwin Coumans
Fri Oct 05, 2018 1:30 am
Forum: PyBullet Support and Feedback
Topic: Car Simulation for Radar
Replies: 6
Views: 1296

Re: Car Simulation for Radar

It is better to add some fixed dummy links in the URDF file. Then let getLinkState compute the world space position and world space velocity for those dummy links. You could create a small pybullet test and share it on github, plot the curve with matplotlib (keep all dependencies to a minimum) link ...
by Erwin Coumans
Fri Oct 05, 2018 1:04 am
Forum: PyBullet Support and Feedback
Topic: Programmatically create a multi-body chain
Replies: 2
Views: 1237

Re: Programmatically create a multi-body chain

We didn't expose spherical joints in PyBullet yet, since none of our robots have spherical joints. You can use multiple revolute joints though. >> Is there a way to specify the joint position w.r.t. the parent body, Yes. I would suggest first learning a bit more about URDF, that gives a better idea....
by Erwin Coumans
Fri Oct 05, 2018 12:56 am
Forum: PyBullet Support and Feedback
Topic: Moving from Bullet 2 to Pybullet
Replies: 5
Views: 1265

Re: Moving from Bullet 2 to Pybullet

Yes, the GUI mode is primarily as debug visualizer. PyBullet has a plugin system (loadPlugin) to customize things. >> 1. Have bodies MotionStates in pyBullet? No motion states, but you can write a plugin that gets all notifications of changes, we have some internal plugin for this to notify an exter...