Search found 4194 matches

by Erwin Coumans
Tue Mar 17, 2020 5:44 pm
Forum: General Bullet Physics Support and Feedback
Topic: Pip install 2.6.6 - issues - Windows 10
Replies: 4
Views: 361

Re: Pip install 2.6.6 - issues - Windows 10

I had a closer look and fixed the issue(s).

Try again using pybullet-2.6.9
pip install pybullet --upgrade
by Erwin Coumans
Tue Mar 17, 2020 3:35 pm
Forum: General Bullet Physics Support and Feedback
Topic: Pip install 2.6.6 - issues - Windows 10
Replies: 4
Views: 361

Re: Pip install 2.6.6 - issues - Windows 10

You are not using vs2019, but Visual C++ for Python\9.0.

Uninstall visual c++ for Python and try again,using the command prompt of visual studio 2019.
by Erwin Coumans
Mon Mar 16, 2020 8:35 pm
Forum: General Bullet Physics Support and Feedback
Topic: Gravity setting for accurate joint force/torque data
Replies: 1
Views: 144

Re: Gravity setting for accurate joint force/torque data

This is expected: joint reaction forces are influenced by gravity acceleration, there is no explicit gravity compensation performed. The gravity acceleration is N/kg. Also, for more help you may want to create a small reproduction case. There are various robots available in PyBullet SDK (panda, xArm...
by Erwin Coumans
Wed Mar 11, 2020 11:56 pm
Forum: PyBullet Support and Feedback
Topic: Documents for creating environments for grasping
Replies: 1
Views: 220

Re: Documents for creating environments for grasping

First, you need to learn how to create an OpenAI Gym environment with PyBullet: https://medium.com/@gerardmaggiolino/creating-openai-gym-environments-with-pybullet-part-1-13895a622b24 then you should investigate how this script works: https://github.com/bulletphysics/bullet3/blob/master/examples/pyb...
by Erwin Coumans
Tue Mar 10, 2020 4:05 am
Forum: PyBullet Support and Feedback
Topic: Maximum number of multibody links?
Replies: 2
Views: 378

Re: Maximum number of multibody links?

There is currently a maximum of 128 links (see MAX_DEGREE_OF_FREEDOM)
The intention was for typical robots, which usually have only tens of links.
by Erwin Coumans
Fri Dec 20, 2019 12:12 am
Forum: PyBullet Support and Feedback
Topic: JOINT_PLANAR/SPHERICAL problem
Replies: 2
Views: 832

Re: JOINT_PLANAR/SPHERICAL problem

We only tested spherical joints in deep_mimic through URDF, not programmatically. Have you tried that? Here is a patch that enables spherical joint creation through the API (instead of URDF): https://github.com/bulletphysics/bullet3/pull/2551 Attached is an example that works after applying this pat...
by Erwin Coumans
Fri Dec 20, 2019 12:08 am
Forum: PyBullet Support and Feedback
Topic: Inaccurate RayTest in Pybullet
Replies: 2
Views: 521

Re: Inaccurate RayTest in Pybullet

Yes, by default we use convex hulls. Best to create a convex decomposition for moving objects (using VHACD, there are utils from obj -> vhacd). See this example: https://github.com/bulletphysics/bullet3/blob/master/data/teddy_vhacd.urdf For concave static trangle meshes, you can mark them as 'concav...
by Erwin Coumans
Mon Dec 09, 2019 5:32 pm
Forum: General Bullet Physics Support and Feedback
Topic: curved trajectory(rolling Friction) fix for bullet in unity
Replies: 6
Views: 793

Re: curved trajectory(rolling Friction) fix for bullet in unity

Good point, I will create a 2.89 release soon (in October was just a file change, not a real 'tag')
by Erwin Coumans
Fri Nov 22, 2019 4:56 am
Forum: General Bullet Physics Support and Feedback
Topic: Maximum angular velocity
Replies: 5
Views: 2107

Re: Maximum angular velocity

>> I know how to shift CoM before the simulation starts with createMultibody, but how to do it during the simulation I recommend to create an additional link (without visual shape, but with some collision shape) along a slider joint, and move that link. You can change the mass of that link using pyb...
by Erwin Coumans
Wed Nov 20, 2019 5:56 pm
Forum: General Bullet Physics Support and Feedback
Topic: Collision detection failed for Ellipsoid shapes
Replies: 7
Views: 1034

Re: Collision detection failed for Ellipsoid shapes

drleviathan makes good points.

Aside from that, you could provide a full working small example (single c++ file, no dependencies other than Bullet) and file an issue here:
https://github.com/bulletphysics/bullet3
it accepts zip file attachments, or just add the code inline.
by Erwin Coumans
Thu Oct 24, 2019 1:58 am
Forum: PyBullet Support and Feedback
Topic: What's the best way to pin a rigid body to another rigid body?
Replies: 1
Views: 923

Re: What's the best way to pin a rigid body to another rigid body?

The best way is to create a new URDF and attach them as a fixed joint. You can use the URDF editor to do this. See this example how to combine a car and a kuka: https://github.com/bulletphysics/bullet3/blob/master/examples/pybullet/gym/pybullet_utils/examples/combineUrdf.py Alternatively, you get so...
by Erwin Coumans
Thu Oct 24, 2019 1:56 am
Forum: PyBullet Support and Feedback
Topic: How to convert rotation matrix to quaternion in PyBullet
Replies: 2
Views: 1095

Re: How to convert rotation matrix to quaternion in PyBullet

Only Euler <-> Quaternion conversions are exposed in PyBullet, not the Matrix <-> Quaternion yet.
by Erwin Coumans
Thu Oct 24, 2019 1:55 am
Forum: PyBullet Support and Feedback
Topic: Segment-wise collision detection
Replies: 1
Views: 637

Re: Segment-wise collision detection

You could use getClosestPoints to get a better conservative answer how far you can safely move, and then use bigger steps along your trajectory.
by Erwin Coumans
Thu Oct 24, 2019 1:53 am
Forum: PyBullet Support and Feedback
Topic: The difference between setJointMotorControl2 and resetJointState
Replies: 1
Views: 637

Re: The difference between setJointMotorControl2 and resetJointState

reset* functions teleport the robot into some state, ignoring all dynamics. setJointMotorControl2 will set some targets and let the simulation try to achieve those, so they obey the laws of physics. The examples may use one or the other. It is best to never use reset* functions while simulating, onl...
by Erwin Coumans
Thu Sep 05, 2019 2:35 pm
Forum: PyBullet Support and Feedback
Topic: Dynamically attached fixed joint is not fix
Replies: 1
Views: 869

Re: Dynamically attached fixed joint is not fix

Mouse forces are very strong and possibly stronger than the fixed joint constraint forces. It is better to attach a fixed joint as part of the urdf instead of using a constraint.