Topological Modeling for Cosmos Action Forward Dynamics

[teerthsharma]

Proposal

I would like to contribute a cohesive topology-aware modeling and evaluation layer for Cosmos3 action forward dynamics.

The goal is to add optional, side-effect-free tooling that helps inspect whether generated robotics forward-dynamics rollouts preserve useful topological structure across autoregressive chunks. This is not intended to change default generation behavior.

Scope

FD/FDTD modeling

Use finite-difference and time-domain rollout intuition to frame visual forward dynamics as evolving field-like structure. The contribution would keep this as modeling/evaluation language, not as a replacement for Cosmos3 inference.

Topology metrics

Add lightweight metrics for generated FD rollouts, including:

• connected-component counts;
• loop/hole proxies through foreground/background topology;
• Euler-characteristic-style summaries;
• frame-to-frame and chunk-boundary topology drift;
• stability scores over DROID/UMI robotics chunks;
• optional persistent-homology enrichment when suitable dependencies are available.

The core implementation can stay dependency-light and operate over binary/labeled masks or point-cloud proxies, with generated JSON/CSV summaries.

Topological inference framing

Document a path toward manifold-state reasoning, Betti-stability, sparse neighborhood reasoning, and theorem/proof-gated convergence concepts as future extension points for evaluating rollout stability.

Swarm robotics extension

Document a future path for multi-agent robot/model specialists using sparse top-k routing informed by topology-aware state similarity, reliability, cost, and utilization signals.

Intended PR shape

One cohesive PR, not several unrelated contributions:

1. add a small topology helper/evaluator near the Cosmos3 action FD cookbook;
2. add deterministic synthetic-mask tests for component, hole, drift, and stability behavior;
3. add README/cookbook documentation for running the evaluator on robotics FD outputs;
4. add a clear design note separating implemented functionality from future topological inference and swarm-routing extensions.

Non-goals

• No change to default Cosmos3 model inference.
• No required segmentation model dependency.
• No GPU or training requirement in CI.
• No claim of improved generation quality without validation artifacts.
• No vendoring of external research prototype code.

Question for maintainers

Would this fit best under cookbooks/cosmos3/generator/action/ as an optional evaluation helper and cookbook section, or would maintainers prefer it under evaluation/ with a benchmark-style layout?

[oomgpu]

Hi @teerthsharma ,

Answering your question directly, if the cookbook is a teaching/example I would suggest adding it under cookbooks/cosmos3/generator/action/ . If it leans more towards evaluations, such as getting consistent results, I would recommend placing it under evaluation/.

The intended PR shape sounds good! I would ask to not include the future path forwards for topological inference or swarm-routing extensions, you are welcome to fork and and push in a separate repo.

When you have your PR ready we can loop in the owners for a final review. Thank you for putting this proposal together.