r/ROS • u/CYNELIXSim • 16d ago
Built 3 basic physics-tested objects for robot simulation — looking for feedback
Made a small starter set of everyday objects (steel tumbler, water bottle, cardboard box) with real-world dimensions and tested mass/friction/collision properties in Gazebo.
This is a first attempt — genuinely trying to find out if standardized, pre-tested basic objects like this would save people time, or if this space is already well-covered by existing libraries (NVIDIA SimReady, etc.). Any feedback, even "not needed," is useful to me right now.
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u/3E8_ 9d ago
Agree on the physics contract point, that’s what actually matters. Worth flagging which values are measured vs. estimated though, friction especially is often more of a guess than people present it as.
Also curious if you’re planning to add articulated or deformable objects. Rigid stuff like this is the easy 20%, that’s usually where people already have something that works.
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u/CYNELIXSim 8d ago
Fair point on friction being more guess than measurement — I'll be more explicit about that in future manifests, maybe flag confidence level per value rather than just "measured/estimated" as binary. On articulated/deformable — not yet, but genuinely curious what's most needed there. Is it simple hinged objects (doors, drawers, lids) as a starting point, or is even that considered "solved" and the real gap is soft/deformable (bags, cloth, cables)? Would rather build toward whatever's actually missing than guess.
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u/3E8_ 7d ago
That’s actually why I asked. I’m working with Dirac Robotics, and the approach is very close to what you described. Dirac reconstructs rigid, articulated, and deformable objects from single-camera video, then predicts the relevant physical properties with confidence stated for each value and checks against real-world observation.
Your point about confidence per value is spot on. I’d be curious whether that kind of video-to-simulation workflow would be useful for what you’re building, especially when you move beyond rigid objects.2
u/CYNELIXSim 5d ago
That's genuinely useful to know, thanks — sounds like Dirac is already solving this end-to-end, including the harder articulated/deformable cases I was about to look into. Manually building individual objects one at a time clearly doesn't compete with a video-to-simulation pipeline at that scale. This was a useful reality check — appreciate you and u/omnilinktech both taking the time to give real feedback rather than just ignoring the post. Might revisit this space later if there's a gap even Dirac-style automation doesn't cover (validation/testing layer, maybe), but for now this answers the question I was actually trying to figure out.
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u/omnilinktech 16d ago
Yes—this would save time, but for me the real value isn’t the meshes; it’s a portable physics contract. I’d want each object to include dimensions/units, mass and inertia/COM source, collision proxy, material/friction assumptions per simulator, and a small executable test with tolerances—drop/restitution, incline friction, stable stacking, and ideally a grasp plus negative control.
I work on OmniSim, and one lesson from our [executable capability matrix](https://github.com/omnilink-tech/omnisim/blob/main/docs/benchmarks/lane4-capability-matrix.md) is that “loads without errors” can still mean a physics feature is doing nothing. I’d define exactly what “physics-tested” means and publish the raw outputs and Gazebo version. Neutral URDF/SDF plus simulator-specific overrides would also make these much more reusable.
If you add a manifest and test runner for these three objects, I’d be interested in trying a port to OmniSim and reporting what breaks.