Genesis-Embodied-AI
[Bug]: FEM and Rigid Entity Collision Bug
Bug Description
Hello everyone, I tried to model collision in between FEM and Rigid Entity. But, there seems to be a bug, which I couldnt solve. Do you guys have any idea about problem?
Steps to Reproduce
import argparse
import numpy as np
import os
import torch
from dask.order import order
from mpmath import euler
from pygel3d.hmesh import minimize_dihedral_angle
from os import path
os.environ['PYOPENGL_PLATFORM'] = 'glx'
import genesis as gs
def main():
parser = argparse.ArgumentParser()
parser.add_argument("-v", "--vis", action="store_true", default=False)
args = parser.parse_args()
########################## init ##########################
gs.init(seed=0, precision="32", logging_level="debug")
########################## create a scene ##########################
scene = gs.Scene(
sim_options=gs.options.SimOptions(
dt=4e-3,
substeps=10,
),
coupler_options=gs.options.CouplerOptions(
rigid_fem=True,
),
rigid_options=gs.options.RigidOptions(
dt=0.01,
gravity=(0,0,-9.8),
enable_collision=True,
constraint_solver=gs.constraint_solver.Newton,
iterations=200,
tolerance=1e-7,
integrator=gs.integrator.implicitfast,
use_contact_island=True,
),
fem_options=gs.options.FEMOptions(
damping=0.1,
),
viewer_options=gs.options.ViewerOptions(
camera_pos=(9.6, 4.8, 14.0),
camera_lookat=(0.0, 0.0, 0.0),
camera_fov=35,
max_FPS=30,
),
show_viewer=args.vis,
vis_options=gs.options.VisOptions(
#visualize_mpm_boundary=True,
),
)
cam = scene.add_camera(
res=(1280, 800),
pos=(5.5, 6.5, 3.2),
lookat=(0.5, 1.5, 1.5),
fov=30,
GUI=True,
)
plane = scene.add_entity(
material=gs.materials.Rigid(),
morph=gs.morphs.URDF(file="urdf/plane/plane.urdf", fixed=True),
)
E, nu = 1.e7,0.3
rho = 100.0
obj1 = scene.add_entity(
material=gs.materials.Rigid(
rho=rho,
friction=1.0,
),
morph=gs.morphs.Sphere(
pos=(0.0, 2.0, 0.5),
radius=0.2,
),
surface=gs.surfaces.Iron(),
)
obj2 = scene.add_entity(
material=gs.materials.FEM.Elastic(
E=E,
nu=nu,
rho=rho,
model="linear",
),
morph=gs.morphs.Box(
pos=(0.0, 0.0, 0.5),
size=(0.5,0.5,0.5),
),
surface=gs.surfaces.Metal(
color=(0.6, 1.0, 0.8, 1.0),
vis_mode="visual",
),
)
scene.build()
cam.start_recording()
horizon = 1000
for i in range(horizon):
if i < 400:
obj1.set_dofs_velocity([0.0, -2.0, 0.0,0.0,0.0,0.0])
scene.step()
cam.render()
cam.stop_recording(save_to_filename="fem_rigid_entity.mp4", fps=60)
if __name__ == "__main__":
main()
Expected Behavior
I expect collision in between entities
Screenshots/Videos
https://github.com/user-attachments/assets/a8a60b66-b6ab-4209-8b72-1716ebb2e83e
Relevant log output
Environment
- OS: [e.g. Ubuntu 24.04 24H2]
- GPU/CPU [e.g. QUADRO RTX 4000, M3pr, Intel I9-9900k] (N/A if no GPU/CPU)
- GPU-driver version (N/A if no GPU)
- CUDA / CUDA-toolkit version
Release version or Commit ID
version 0.2.1
Additional Context
No response
Hi @duburcqa, can you see the video?
https://drive.google.com/file/d/1GpmkRl621ZluS__eDgaLgjRQbhEe13q5/view?usp=drive_link
Yes I do! Here it is (after fixing encoding issue using ffmpeg -i fem_rigid_entity.mp4 -c:v libx264 -crf 18 -preset slow -c:a copy fem_rigid_entity_.mp4) to make sure it does not disappear because the link gets broken at some point:
https://github.com/user-attachments/assets/b95c32b9-25cc-45dd-808f-6ea78094503f
Hi @duburcqa,
Do you have suggestion for problem I have been experiencing?
Hi, I just checked. The issue is that our current collision detection only handles collisions between FEM vertices and rigid bodies. In this case, the FEM vertices are very sparse (and hollow), so the ball passed through without colliding with any vertices. You can try increasing the number of vertices in the FEM object or using a larger ball. In parallel, we’re planning to implement a more robust coupling system.
Hi @YilingQiao,
I tried increasing ball size and it still gives the same response. I am looking forward to new coupling system.
By the way, I also tried using 2 fem entity within this script and I got below error:
"AttributeError: 'FEMEntity' object has no attribute '_n_surfaces'. Did you mean: 'n_surfaces'?"
Is there any solution for this?
Hi @YilingQiao,
Here is the complete error message:
Traceback (most recent call last):
File "/home/bahadir/Desktop/genesis/genesis/part_1/modelling/fem_entity/fem_try.py", line 127, in <module>
main()
File "/home/bahadir/Desktop/genesis/genesis/part_1/modelling/fem_entity/fem_try.py", line 93, in main
obj2 = scene.add_entity(
^^^^^^^^^^^^^^^^^
File "/home/bahadir/anaconda3/lib/python3.12/site-packages/genesis/utils/misc.py", line 38, in wrapper
return method(self, *args, **kwargs)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/bahadir/anaconda3/lib/python3.12/site-packages/genesis/engine/scene.py", line 359, in add_entity
entity = self._sim._add_entity(morph, material, surface, visualize_contact)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/bahadir/anaconda3/lib/python3.12/site-packages/genesis/engine/simulator.py", line 146, in _add_entity
entity = self.fem_solver.add_entity(self.n_entities, material, morph, surface)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/bahadir/anaconda3/lib/python3.12/site-packages/genesis/engine/solvers/fem_solver.py", line 176, in add_entity
s_start=self.n_surfaces,
^^^^^^^^^^^^^^^
File "/home/bahadir/anaconda3/lib/python3.12/site-packages/taichi/lang/kernel_impl.py", line 1236, in _getattr
return x(self)
^^^^^^^
File "/home/bahadir/anaconda3/lib/python3.12/site-packages/genesis/engine/solvers/fem_solver.py", line 641, in n_surfaces
return sum([entity.n_surfaces for entity in self.entities])
^^^^^^^^^^^^^^^^^
File "/home/bahadir/anaconda3/lib/python3.12/site-packages/taichi/lang/kernel_impl.py", line 1236, in _getattr
return x(self)
^^^^^^^
File "/home/bahadir/anaconda3/lib/python3.12/site-packages/genesis/engine/entities/fem_entity.py", line 454, in n_surfaces
return self._n_surfaces
^^^^^^^^^^^^^^^^
File "/home/bahadir/anaconda3/lib/python3.12/site-packages/taichi/lang/kernel_impl.py", line 1221, in _getattr
x = super(cls, self).__getattribute__(item)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/bahadir/anaconda3/lib/python3.12/site-packages/taichi/lang/kernel_impl.py", line 1221, in _getattr
x = super(cls, self).__getattribute__(item)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AttributeError: 'FEMEntity' object has no attribute '_n_surfaces'. Did you mean: 'n_surfaces'?
It should not happen in the latest commit? Can you have another try. This script runs fine on my side
import argparse
import numpy as np
import os
import torch
from dask.order import order
from mpmath import euler
from pygel3d.hmesh import minimize_dihedral_angle
from os import path
os.environ['PYOPENGL_PLATFORM'] = 'glx'
import genesis as gs
def main():
parser = argparse.ArgumentParser()
parser.add_argument("-v", "--vis", action="store_true", default=False)
args = parser.parse_args()
########################## init ##########################
gs.init(seed=0, precision="32", logging_level="debug")
########################## create a scene ##########################
scene = gs.Scene(
sim_options=gs.options.SimOptions(
dt=4e-3,
substeps=10,
),
coupler_options=gs.options.CouplerOptions(
rigid_fem=True,
),
rigid_options=gs.options.RigidOptions(
dt=0.01,
gravity=(0,0,-9.8),
enable_collision=True,
constraint_solver=gs.constraint_solver.Newton,
iterations=200,
tolerance=1e-7,
integrator=gs.integrator.implicitfast,
use_contact_island=True,
),
fem_options=gs.options.FEMOptions(
damping=0.1,
),
viewer_options=gs.options.ViewerOptions(
camera_pos=(9.6, 4.8, 14.0),
camera_lookat=(0.0, 0.0, 0.0),
camera_fov=35,
max_FPS=30,
),
show_viewer=args.vis,
vis_options=gs.options.VisOptions(
#visualize_mpm_boundary=True,
),
)
cam = scene.add_camera(
res=(1280, 800),
pos=(5.5, 6.5, 3.2),
lookat=(0.5, 1.5, 1.5),
fov=30,
GUI=True,
)
plane = scene.add_entity(
material=gs.materials.Rigid(),
morph=gs.morphs.URDF(file="urdf/plane/plane.urdf", fixed=True),
)
E, nu = 1.e7,0.3
rho = 100.0
obj1 = scene.add_entity(
material=gs.materials.Rigid(
rho=rho,
friction=1.0,
),
morph=gs.morphs.Sphere(
pos=(0.0, 2.0, 0.5),
radius=0.2,
),
surface=gs.surfaces.Iron(),
)
obj2 = scene.add_entity(
material=gs.materials.FEM.Elastic(
E=E,
nu=nu,
rho=rho,
model="linear",
),
morph=gs.morphs.Box(
pos=(0.0, 0.0, 0.5),
size=(0.5,0.5,0.5),
),
surface=gs.surfaces.Metal(
color=(0.6, 1.0, 0.8, 1.0),
vis_mode="visual",
),
)
obj3 = scene.add_entity(
material=gs.materials.FEM.Elastic(
E=E,
nu=nu,
rho=rho,
model="linear",
),
morph=gs.morphs.Box(
pos=(0.0, 0.0, 2.5),
size=(0.5,0.5,0.5),
),
surface=gs.surfaces.Metal(
color=(0.6, 1.0, 0.8, 1.0),
vis_mode="visual",
),
)
scene.build()
cam.start_recording()
horizon = 1000
for i in range(horizon):
if i < 400:
obj1.set_dofs_velocity([0.0, -2.0, 0.0,0.0,0.0,0.0])
scene.step()
if __name__ == "__main__":
main()
Hi @YilingQiao,
Still the same error
Traceback (most recent call last):
File "/home/bahadir/Desktop/genesis/genesis/part_1/modelling/fem_entity/fem_try2.py", line 129, in <module>
main()
File "/home/bahadir/Desktop/genesis/genesis/part_1/modelling/fem_entity/fem_try2.py", line 102, in main
obj3 = scene.add_entity(
^^^^^^^^^^^^^^^^^
File "/home/bahadir/anaconda3/lib/python3.12/site-packages/genesis/utils/misc.py", line 38, in wrapper
return method(self, *args, **kwargs)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/bahadir/anaconda3/lib/python3.12/site-packages/genesis/engine/scene.py", line 359, in add_entity
entity = self._sim._add_entity(morph, material, surface, visualize_contact)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/bahadir/anaconda3/lib/python3.12/site-packages/genesis/engine/simulator.py", line 146, in _add_entity
entity = self.fem_solver.add_entity(self.n_entities, material, morph, surface)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/bahadir/anaconda3/lib/python3.12/site-packages/genesis/engine/solvers/fem_solver.py", line 176, in add_entity
s_start=self.n_surfaces,
^^^^^^^^^^^^^^^
File "/home/bahadir/anaconda3/lib/python3.12/site-packages/taichi/lang/kernel_impl.py", line 1236, in _getattr
return x(self)
^^^^^^^
File "/home/bahadir/anaconda3/lib/python3.12/site-packages/genesis/engine/solvers/fem_solver.py", line 641, in n_surfaces
return sum([entity.n_surfaces for entity in self.entities])
^^^^^^^^^^^^^^^^^
File "/home/bahadir/anaconda3/lib/python3.12/site-packages/taichi/lang/kernel_impl.py", line 1236, in _getattr
return x(self)
^^^^^^^
File "/home/bahadir/anaconda3/lib/python3.12/site-packages/genesis/engine/entities/fem_entity.py", line 454, in n_surfaces
return self._n_surfaces
^^^^^^^^^^^^^^^^
File "/home/bahadir/anaconda3/lib/python3.12/site-packages/taichi/lang/kernel_impl.py", line 1221, in _getattr
x = super(cls, self).__getattribute__(item)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
File "/home/bahadir/anaconda3/lib/python3.12/site-packages/taichi/lang/kernel_impl.py", line 1221, in _getattr
x = super(cls, self).__getattribute__(item)
^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^^
AttributeError: 'FEMEntity' object has no attribute '_n_surfaces'. Did you mean: 'n_surfaces'?
File "/home/bahadir/anaconda3/lib/python3.12/site-packages/genesis/engine/entities/fem_entity.py", line 454, in n_surfaces
return self._n_surfaces
It's not the latest commit. Line454 in fem_entity.py is like that
https://github.com/Genesis-Embodied-AI/Genesis/blob/a313d457ea84b55be97b804c723cfe34c504e136/genesis/engine/entities/fem_entity.py#L454
Can you install the latest commit?
pip install -e .
Hi @YilingQiao,
I installed latest version and successfully run it. Here is the latest video of sim.
https://drive.google.com/file/d/1t8Cx9Lmp_H0OapduFHPkanp3EfVioQm4/view?usp=sharing
But, there are still rigid-fem and fem-fem entity collision bugs. Is there any way to solve the problem?
Hi @YilingQiao,
I installed latest version and successfully run it. Here is the latest video of sim.
https://drive.google.com/file/d/1t8Cx9Lmp_H0OapduFHPkanp3EfVioQm4/view?usp=sharing
But, there are still rigid-fem and fem-fem entity collision bugs. Is there any way to solve the problem?
me too
@Libero0809 is working on it. We will add a better collision detection and resolution
Hi @duburcqa and @Libero0809,
I still get same behavior shown in video that I uploaded. What should I do to overcome this problem?