Belt conveyor simulation

[h3ct0r]

Hello guys, is there a way to simulate a belt conveyor system (a unified big soft belt) with Genesis? Any pointers on how to do it?

Thanks!

[55155]

Hello, the PBD solver includes a material called “cloth.” If we modify its physical properties a bit, couldn’t it become a kind of belt? And what do you think about the idea of coupling it with a robot?

[h3ct0r]

Hey! The cloth from the PBD solver looks promising, I created a simple conveyor "belt" mesh and tried to load it into the cloth example. However the script hangs on the Remeshing for tetrahedralization... step. Do you know what could be the issue here?

The obj and mtl files are here:

• obj https://www.dropbox.com/scl/fi/oknh54z1cqfso6m8m62wr/belt_v0-Body.obj?rlkey=8jxxpk3i8adb6oqneuvuysbx2&dl=0
• mtl https://www.dropbox.com/scl/fi/vdmow5j129vsmut6ejz9f/belt_v0-Body.mtl?rlkey=4qg72nge4za9rrmallxco8m1w&dl=0

Thanks!

import genesis as gs
gs.init(seed=0, precision="32", logging_level="debug")

scene = gs.Scene(
    sim_options=gs.options.SimOptions(
        dt=0.01,
        substeps=10,
    ),
    viewer_options=gs.options.ViewerOptions(
        camera_fov=30,
        res=(800, 600),
        max_FPS=60,
    ),
    show_viewer=True,
)

plane = scene.add_entity(
    morph=gs.morphs.Plane(),
)

cloth_2 = scene.add_entity(
    material=gs.materials.PBD.Cloth(),
    morph=gs.morphs.Mesh(
        file="/Users/XXX/conveyor_belt_sim/belt_v0-Body.obj",
        scale=2.0,
        pos=(0, 0, 1.0),
        euler=(0.0, 0, 0.0),
    ),
    surface=gs.surfaces.Default(
        color=(0.8, 0.4, 0.2, 1.0),
        vis_mode="particle",
    ),
)
scene.build()

cloth_2.fix_particles(cloth_2.find_closest_particle((-1, -1, 1.0)))

horizon = 1000
for i in range(horizon):
    scene.step()

[55155]

It seems to be the same error I encountered before. You need to design the conveyor belt mesh as a 2D surface to use the PBD.cloth() class. It looks like the issue is caused by instantiating a volumetric object instead.

[duburcqa]

Related to #1680

[h3ct0r]

Thanks for the update @duburcqa , any pointers on where to start looking to develop this functionality and create a PR for the feature?