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arxiv: 2605.24047 · v1 · pith:PU4MUFHOnew · submitted 2026-05-21 · 💻 cs.CV

EMMA: Extracting Multiple physical parameters from Multimodal Data

Pith reviewed 2026-06-30 16:34 UTC · model grok-4.3

classification 💻 cs.CV
keywords physics-informed learningmultimodal parameter estimationdynamical systemscontinuous-time neural networksvideo-based dynamics recoveryhidden input inference
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The pith

EMMA recovers all identifiable dynamical parameters of a system directly from raw multimodal observations using a unified continuous-time model.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper presents EMMA as a framework that jointly infers explicit parameters, hidden dynamics, and calibration factors from video, audio, and time-series data. It does so by training a Liquid Time-Constant network on aligned multimodal inputs while enforcing consistency with known governing differential equations through a physics-constrained loss. The approach is tested across more than one hundred scenarios that include standard benchmarks, real robotic platforms with hidden actuation, and chart-based measurements from biological and chaotic systems. A sympathetic reader would care because the method removes the need for segmentation masks, known initial conditions, or single-modality restrictions that limit earlier video-only techniques.

Core claim

EMMA recovers all identifiable dynamical parameters of a system directly from raw video, audio, and image-based time-series observations by performing joint inference of explicit parameters, implicit dynamical components, and calibration invariants within a unified continuous-time model that combines an LTC network for latent dynamics with a physics-constrained loss enforcing the governing differential equations.

What carries the argument

The Liquid Time-Constant network paired with a physics-constrained loss that aligns multimodal features to known differential equations across video trajectories, acoustic signatures, and chart measurements.

If this is right

  • Parameters can be recovered under forced, implicit, and multivariate dynamics without segmentation masks or differentiable rendering.
  • The same pipeline works on real rover and quadrotor systems that have hidden actuation inputs.
  • Performance exceeds single-modality and equation-discovery baselines on five standard dynamical benchmarks and 75 Delfys videos.
  • The framework extends to simulation-chart studies of biological and chaotic systems.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • If the known-equation requirement can be relaxed, the method could be combined with equation-discovery techniques to handle partially specified systems.
  • The multimodal alignment step suggests possible use in domains where only opportunistic recordings exist, such as field biology or infrastructure monitoring.
  • Scaling the continuous-time model to higher-dimensional state spaces would require checking whether the LTC component remains stable under increased latent dimensionality.

Load-bearing premise

The governing differential equations of the underlying system are known in advance and can be encoded directly into a differentiable loss that stays consistent across modalities and hidden inputs.

What would settle it

Demonstrating that the recovered parameters deviate significantly from ground-truth values on a new system whose equations are known but whose video and audio contain substantial occlusion and unknown forcing would falsify the central claim.

Figures

Figures reproduced from arXiv: 2605.24047 by Ayan Banerjee, Farhat Shaikh, Sandeep Gupta.

Figure 1
Figure 1. Figure 1: Given unified multi-modal observations (video, audio, image), [PITH_FULL_IMAGE:figures/full_fig_p002_1.png] view at source ↗
Figure 2
Figure 2. Figure 2: EMMA Architecture. Multi-modal inputs (video, audio and image) are processed through specialized pipelines into unified temporal representations. An LTC-NN learns latent dynamics h(t) and predicts physical parameters θ. A differentiable physics simulator validates predictions, enabling end-to-end gradient flow. The framework successfully reconstructs digital twin drone (example shown) from multi-modal obse… view at source ↗
Figure 3
Figure 3. Figure 3: Intuition for using LTC-NN for parameter estimation. [PITH_FULL_IMAGE:figures/full_fig_p005_3.png] view at source ↗
read the original abstract

We introduce EMMA, a physics-informed multimodal framework that recovers all identifiable dynamical parameters of a system directly from raw video, audio, and image-based time-series observations. Unlike prior video-only approaches that struggle with occluded states, hidden actuation inputs, or assumptions about known initial conditions and coordinate frames, EMMA performs joint inference of explicit parameters, implicit dynamical components, and calibration invariants within a unified continuous-time model. EMMA leverages a Liquid Time-Constant (LTC) network to learn latent dynamics from heterogeneous modalities while a physics-constrained loss enforces consistency with the governing differential equations. A unified feature pipeline enables consistent alignment across video trajectories, acoustic signatures, and chart-derived measurements, allowing EMMA to estimate parameters under forced, implicit, and multivariate dynamics without requiring segmentation masks, differentiable rendering, or specialized sensors. Across 100+ scenarios including five standard dynamical benchmarks (75 Delfys videos), real-world rover and quadrotor systems with hidden inputs, and simulation-chart case studies spanning biological and chaotic systems, EMMA delivers robust multi-parameter recovery and significantly outperforms existing single-modality and equation-discovery baselines. Our results establish EMMA as a general, scalable solution for physics-consistent model extraction from opportunistic multimodal data. Code and data are available at: https://github.com/ImpactLabASU/EMMA-CVPR2026

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

2 major / 2 minor

Summary. The paper introduces EMMA, a physics-informed multimodal framework that recovers all identifiable dynamical parameters of a system directly from raw video, audio, and image-based time-series observations. It uses a Liquid Time-Constant (LTC) network to learn latent dynamics from heterogeneous modalities, a physics-constrained loss to enforce consistency with governing differential equations, and a unified feature pipeline for alignment across modalities. The method performs joint inference of explicit parameters, implicit dynamical components, and calibration invariants in a continuous-time model, handling forced, implicit, and multivariate dynamics without segmentation masks, differentiable rendering, or known initial conditions. Experiments across 100+ scenarios (five standard dynamical benchmarks with 75 Delfys videos, real-world rover/quadrotor with hidden inputs, and simulation-chart studies on biological/chaotic systems) show robust multi-parameter recovery outperforming single-modality and equation-discovery baselines.

Significance. If the central claims hold, the work would be significant for enabling scalable, physics-consistent parameter extraction from opportunistic multimodal data in robotics, system identification, and related fields. Strengths include the unified handling of hidden inputs and multiple modalities, the release of code and data, and the breadth of evaluated scenarios (benchmarks plus real systems).

major comments (2)
  1. [Method] Method section (around the physics-constrained loss definition): the claim that the loss enforces consistency across modalities and hidden inputs without circularity requires the explicit mathematical form of the loss (e.g., how the LTC latent dynamics are coupled to the known governing ODEs) to be shown; without it the central recovery claim cannot be verified as non-circular.
  2. [Experiments] Experiments section, Table on benchmark results: the reported outperformance over equation-discovery baselines must include the exact quantitative metrics (e.g., parameter error norms) and ablation on the contribution of each modality; the abstract's summary of 'significantly outperforms' is load-bearing for the general-solution claim but lacks these details.
minor comments (2)
  1. The abstract states 'Code and data are available at: https://github.com/ImpactLabASU/EMMA-CVPR2026'; confirm the repository contains the exact scripts and datasets used for the 100+ scenarios to support reproducibility.
  2. [Experiments] Clarify the precise list of the 'five standard dynamical benchmarks' and the 75 Delfys videos in the main text or a table, as this is referenced but not enumerated.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for the constructive feedback. We address each major comment below and will revise the manuscript to incorporate the requested clarifications and details.

read point-by-point responses
  1. Referee: [Method] Method section (around the physics-constrained loss definition): the claim that the loss enforces consistency across modalities and hidden inputs without circularity requires the explicit mathematical form of the loss (e.g., how the LTC latent dynamics are coupled to the known governing ODEs) to be shown; without it the central recovery claim cannot be verified as non-circular.

    Authors: We agree that the explicit mathematical form of the physics-constrained loss is necessary to verify the non-circular coupling. In the revised manuscript, we will expand the method section to include the full loss formulation, explicitly detailing how the LTC latent states are coupled to the known governing ODEs, the enforcement of multimodal consistency, and the handling of hidden inputs. revision: yes

  2. Referee: [Experiments] Experiments section, Table on benchmark results: the reported outperformance over equation-discovery baselines must include the exact quantitative metrics (e.g., parameter error norms) and ablation on the contribution of each modality; the abstract's summary of 'significantly outperforms' is load-bearing for the general-solution claim but lacks these details.

    Authors: We acknowledge that the current presentation lacks the requested quantitative precision. We will revise the experiments section to report exact parameter error norms in the benchmark table and add a modality ablation study. These additions will directly support the abstract claims with concrete metrics. revision: yes

Circularity Check

0 steps flagged

No significant circularity detected

full rationale

The abstract and description present EMMA as a standard physics-informed approach that assumes governing differential equations are known a priori and encoded into a differentiable loss to constrain parameter recovery from multimodal data. This matches the stated weakest assumption exactly and does not reduce any claimed prediction or parameter to a fit by construction, self-definition, or self-citation chain. No equations, uniqueness theorems, or ansatzes from prior author work are invoked in a load-bearing way within the provided text. The method is benchmarked against external baselines and datasets, keeping the derivation self-contained against independent verification.

Axiom & Free-Parameter Ledger

0 free parameters · 1 axioms · 0 invented entities

Review performed on abstract only; the central claim rests on the assumption that governing differential equations are known and usable in the loss, plus identifiability of parameters from the given modalities.

axioms (1)
  • domain assumption The governing differential equations of the system are known a priori and can be incorporated into a differentiable loss term.
    Stated in the abstract as the mechanism that enforces consistency with the governing differential equations.

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discussion (0)

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