Pith. sign in

REVIEW 4 major objections 6 minor 28 references

Understanding Particles From Video: Property Estimation of Granular Materials via Visuo-Haptic Learning

T0 review · 4 major / 6 minor · reviewed 2026-08-11 · deepseek-v4-flash

Pith's one-line read Relative particle size and density of granular materials can be estimated from a video alone by projecting probe-dragging motion into a learned latent space.

desk verdict Genuinely new idea—video-only granular property estimation via visuo-haptic learning—but the headline claim rests on post-hoc qualitative latent inspection, not quantitative validation. read the letter →

arxiv 2412.02119 v1 pith:7DJRAJGA submitted 2024-12-03 cs.CV cs.LGcs.RO

classification cs.CVcs.LGcs.RO
keywords granularmaterialsvisuo-hapticlearningpropertyestimationlatentrepresentationparticletrackingprobedraggingvideo-onlyinference
verification ladder T0 review T1 audit T2 compute T3 formal

The pith

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

The reading

This paper tries to establish that a video of a probe being dragged through a granular material is enough to rank that material by particle size and density. It trains an encoder-decoder to predict the measured drag force from visual particle motion, then reads the material's properties from where its video lands in the latent space. The point is practical: property estimation currently needs balances, calipers, hygrometers, or force/tactile sensors, while this method would need only a camera. Evidence comes from fifteen lab materials, unseen materials, handheld-captured clips, and a beach demonstration.

What carries the argument

The load-bearing object is the probe-dragging contact model $F_d = \eta \rho g d_c H^2$, paired with the equality $\sum_i m_i \ddot{x}_i = F_d$ that ties the measured drag force to the visible accelerations of particles in the failure wedge. The network itself is an encoder-decoder: a pre-trained tracker turns each video into trajectories of sampled points, 3D convolutions compress the trajectories into a 4D latent vector, and deconvolutions reconstruct the force sequence used as supervision. After training, two of the four latent dimensions are selected as the implicit property axes for particle size and density.

What would settle it

Prepare granular samples that vary particle size and density independently (same-size beads of different materials, or sieved fractions of the same material), train the same pipeline, and check whether the two chosen latent axes correlate monotonically with independently measured size and density; any strong cross-correlation, or a large latent shift when only shape or moisture changes, would refute the claim.

Watch

Extended reading notes

Core claim

On the paper's own terms, the central discovery is that a network trained to map visual particle trajectories to measured drag force spontaneously organizes its latent space by two physical properties of the grains. With a four-dimensional latent vector, two dimensions arrange the tested materials diagonally by particle size and cluster them by density; unseen materials project into compatible locations, and a handheld camera produces projections close to those from the robot arm. The authors explain the result through the probe-dragging contact model $F_d = \eta \rho g d_c H^2$, where the drag force is proportional to density $\rho$ and particle size $d_c$, so the network's force-supervised learning is expected to encode their visual correlates. The estimator is deliberately relative rather than absolute, ranking materials by projection position rather than returning calibrated physical values.

Load-bearing premise

The property-estimation claim collapses if the two latent dimensions picked after training do not independently encode particle size and density but instead encode some mixture of size, density, shape, friction, moisture, and tracking quality, since the paper's validation is visual alignment with coarse manual groupings rather than direct measurement.

Editorial extensions

If this is right

  • A camera alone, including a smartphone held by hand, can rank granular materials by relative particle size and density in settings where balances, calipers, or force sensors are not available.
  • Training needs no manual property labels: the measured force sequence is the supervisory signal, removing a major labor bottleneck in building granular datasets.
  • The learned property distribution transfers to unseen materials whose probe-dragging behavior resembles the training regime, as shown with new lab grains and beach sands.
  • Materials that violate the assumed failure-wedge behavior, such as wet sand that cracks instead of flowing, project outside the learned distribution and are effectively flagged as out of scope.

Reading between the lines

Editorial extensions of the paper, not claims the author makes directly.

  • Because the contact model couples density and size through the product $\rho d_c$, the two chosen latent axes may encode that product plus other correlated factors (shape, friction, moisture) rather than the two properties separately; an engineered set of particles varying size and density independently would settle what each axis measures.
  • The same recipe—a physics-derived contact relation, force-supervised video encoding, and latent-space inspection—could transfer to other manipulations such as pouring, stirring, or scooping wherever a closed-form relation links visible motion to a material property.
  • The out-of-range projections for crushed peanuts and wet sand suggest the latent space can double as an out-of-distribution detector, signaling when the underlying flow regime assumption fails.
Share X Bluesky LinkedIn Reddit HN

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, and a circularity audit.

Referee Report

4 major / 6 minor

Summary. The paper proposes a visuo-haptic learning framework for estimating the relative particle size and density of granular materials (GMs) from video alone. A probe is dragged through a granular medium while a camera records particle motion and a force/torque sensor records the drag force. The paper uses a simplified contact model Fd = ηρgdcH² (Eq. 1) to motivate an encoder–decoder network: the encoder processes tracked particle trajectories extracted from video, and the decoder predicts the force sequence. Training is supervised by measured force signals, avoiding manual property labels. After training, the decoder is discarded and the 4-dimensional latent space of the encoder is examined; the authors report that two of the four latent dimensions reveal an implicit property distribution in which particle size increases along one direction and density clusters in another (Fig. 6). They evaluate force prediction accuracy, compare against a classification baseline, perform ablations with and without particle tracking, test generalization to handheld-device videos and to beach sands, and select the latent dimension via validation loss (Sec. V-G). The central claim is that relative particle size and density can be estimated from a new video by projecting it into this latent space, using only a camera at inference time.

Significance. If the property-estimation claim is substantiated, the method would be a practical, low-cost tool for ranking granular materials by particle size and density without dedicated instruments, force sensors, or manual labels, with potential applications in agriculture and field geology. The paper's strengths include the use of real-world data (GM15-VF, 15 granular materials, 100 trials each), a physically motivated architecture, a genuine attempt at generalization (unseen GMs, handheld capture, beach sand), and honest reporting of failure cases. The force-inference results are reasonably convincing. However, the headline contribution—property estimation from video—is supported only by qualitative latent-space visualizations, with no quantitative metric of estimation accuracy, no error bars, and no demonstration that the selected latent dimensions robustly and independently encode size and density. This gap is load-bearing and must be addressed before the central claim can be accepted.

major comments (4)
  1. [Sec. V-B, Fig. 6] The property-estimation claim is validated only qualitatively. The paper reports no measured particle sizes or densities, no correlation or regression between latent projections and ground-truth properties, no classification accuracy for the size categories, and no error bars or confidence intervals for the estimated properties. For a paper whose headline is 'relative values of particle size and density can be estimated from video,' this is a load-bearing omission. Please provide quantitative evaluation on held-out GM types: e.g., Spearman rank correlation between latent axis values and measured particle size/density, R² of a linear readout from the latent space, or accuracy of size-category classification, with statistics over random seeds and train/test splits.
  2. [Sec. V-B and Eq. (1)] Nothing in the training objective forces the two selected latent dimensions to independently encode particle size and density. The force target Fd = ηρgdcH² depends, for fixed H and η, only on the product ρ·dc, so any latent factorization that predicts the force equally well is acceptable. The visual trajectories (Σ mi ẍi) could in principle break this symmetry because mi depends on volume as well as density, but the paper provides no check that this occurs. The selection of the two 'property' dimensions is post hoc, and Sec. V-G selects the latent dimensionality by force-prediction loss only, not by property-decoding performance. Please demonstrate that the latent axes are stable across training seeds, that other pairs of latent dimensions do not yield equally interpretable plots, and ideally that a linear decoder or simple regression can recover size and density from the latent code.
  3. [Sec. V-B, Sec. V-F, Sec. VI] The paper's own experiments identify two clear failure cases: crushed peanuts (Fig. 6) and beach sand GM17 with high water content (Fig. 10). The authors acknowledge these cases in Sec. VI, which is commendable, but the conclusion that the method generally estimates relative properties is thereby qualified. The paper should state the intended domain of validity (e.g., dry, non-adhesive, homogeneous granules) and report how many of the tested GM types succeed and fail under the proposed qualitative criterion, rather than presenting these as isolated exceptions. A quantitative accuracy measure would also make the boundary of applicability precise.
  4. [Sec. V-C] The baseline comparison does not quantitatively evaluate property estimation. The baseline is trained for GM classification, and its latent space is only visualized (Fig. 7-b); no metric compares how well the baseline or the proposed method separates properties. Since the claimed advantage is interpretability and property estimation, the comparison should include the same quantitative property-estimation metrics proposed in the first major comment, applied to both methods. As written, the baseline experiment supports a claim about latent-space scatter but not a claim about superior property estimation.
minor comments (6)
  1. [Sec. IV-A] The dataset section reports 100 instances per GM and an 80/10/10 split, but does not state whether the instances are independent repeated trials or sequential frames from a smaller number of drags, nor how the split was randomized. Please clarify to allow reproducibility.
  2. [Eq. (1)] Equation (1) equates a scalar magnitude Fd with a vector sum Σ mi ẍi; please state explicitly that only force magnitudes are considered and define the direction convention. Also, η is described as 'surface morphology' but is not defined dimensionally; a brief note that η is an empirical dimensionless coefficient would help.
  3. [Sec. V-B, Fig. 6] The text says particle density was 'determined by measuring the mass of the same volume.' Please specify whether this is particle density or bulk density, and whether the container tare mass was subtracted; the caption's phrase 'weights of GMs in the same container' is ambiguous.
  4. [Table I] The table header 'BOLD FOR LOWEST VALUES' should be reworded (e.g., 'Boldface indicates the lowest value in each column'), and the loss values should include units or a note that they are normalized MSE.
  5. [Sec. V-G] Table II reports only the mean validation loss for each latent dimension; given the small validation set, standard deviations or error bars should be reported to support the claim that 4 dimensions is uniquely best.
  6. [Sec. V-E] The handheld-device generalization experiment tests only two GMs (coffee bean and sunflower seed) and reports three projected points. This is a useful pilot demonstration, but the text should explicitly frame it as a small pilot rather than a comprehensive generalization study.

Circularity Check

0 steps flagged · score 2.0 of 10

No circularity in the training pipeline; the property-estimation stage is post hoc and underdetermined, but no step reduces by construction to its inputs.

full rationale

The derivation chain is not circular. The encoder-decoder is supervised by measured force sequences from an F/T sensor (Sec. III-C, Sec. IV-A), not by particle size or density labels, so the property values are not fitted inputs renamed as predictions. The contact model Fd = ηρgdcH2 is cited from external physics literature ([9], Albert et al.), not from the authors' own prior work, so the force-property relation is an independent input rather than a self-derived conclusion. Force prediction is benchmarked against held-out force measurements (Sec. V-A, Tab. I), providing an external check of the trained mapping. The property-estimation stage (Sec. V-B) selects two of four latent dimensions after training and interprets them by overlaying manually categorized sizes and container weights; this is a post hoc interpretation rather than a quantity derived from the loss. Because the force target depends on the product ρ·dc, the network is not forced by construction to factorize size and density, and the visual trajectories could in principle break that symmetry, but the paper gives no quantitative proof. That underdetermination is a correctness and validation risk, not a circular reduction. The self-citations present ([2], [11], [28]) are background and future-work references and do not carry the central argument. No equation in the paper is equivalent to its own output by definition, and no load-bearing self-citation chain is present.

Assumptions & free parameters 1 free parameters · 4 assumptions · 0 invented entities

No new physical entities are introduced. The main load-bearing inputs are the cited contact model, the homogeneity assumption, and the modeling assumptions that force supervision and particle tracking preserve property information. One hyperparameter, latent dimension 4, is chosen empirically.

free parameters (1)
  • latent_dim = 4
    The latent space dimension is set to 4 based on validation MSE in Sec. V-G, a model-selection hyperparameter not derived from physics.
assumptions (4)
  • domain assumption Contact model Fd = ηρgdcH2 from Albert et al. [9] holds for the probe-dragging setup.
    Assumed valid for the measured GMs and probe conditions; cited from prior physics literature, not derived in this paper (Sec. III-A).
  • domain assumption Granular materials are homogeneous.
    The contact model and dataset are restricted to homogeneous granules; the paper states this limitation in the conclusion.
  • domain assumption Force supervision forces the latent space to encode physically meaningful property information.
    The training paradigm assumes that mapping video motion to measured force produces latent representations that correlate with particle size and density (Sec. III-C).
  • domain assumption Particle tracking accurately follows granule motion.
    The trajectory input relies on a pretrained CoTracker; the paper notes that crushed peanuts fail due to poor tracking (Sec. V-B).

how reviews work

0 comments
Cite this review

Pith. "Pith review of Understanding Particles From Video: Property Estimation of Granular Materials via Visuo-Haptic Learning." pith.science (2026). https://pith.science/paper/7DJRAJGA

@misc{pith2026241202119,
  author       = {Pith},
  title        = {Pith review of: Understanding Particles From Video: Property Estimation of Granular Materials via Visuo-Haptic Learning},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/7DJRAJGA}},
  note         = {Machine review of arXiv:2412.02119}
}
read the original abstract

Granular materials (GMs) are ubiquitous in daily life. Understanding their properties is also important, especially in agriculture and industry. However, existing works require dedicated measurement equipment and also need large human efforts to handle a large number of particles. In this paper, we introduce a method for estimating the relative values of particle size and density from the video of the interaction with GMs. It is trained on a visuo-haptic learning framework inspired by a contact model, which reveals the strong correlation between GM properties and the visual-haptic data during the probe-dragging in the GMs. After training, the network can map the visual modality well to the haptic signal and implicitly characterize the relative distribution of particle properties in its latent embeddings, as interpreted in that contact model. Therefore, we can analyze GM properties using the trained encoder, and only visual information is needed without extra sensory modalities and human efforts for labeling. The presented GM property estimator has been extensively validated via comparison and ablation experiments. The generalization capability has also been evaluated and a real-world application on the beach is also demonstrated. Experiment videos are available at \url{https://sites.google.com/view/gmwork/vhlearning} .

Figures

Figures reproduced from arXiv: 2412.02119 by the authors.

Figure 1
Figure 1. Overview of this work. (a) Probe-dragging. A simplified GM-tool [PITH_FULL_IMAGE:figures/full_fig_p002_1.png] view at source ↗
Figure 2
Figure 2. Architecture of our visuo-haptic learning framework inspired by the contact model in e.q. (1). The dataset [PITH_FULL_IMAGE:figures/full_fig_p003_2.png] view at source ↗
Figure 3
Figure 3. 15 types of GMs compose the dataset GM15-VF, where the unseen particles are displayed with green backgrounds for their IDs [PITH_FULL_IMAGE:figures/full_fig_p004_3.png] view at source ↗
Figures from the paper (6 more)
Figure 4
Figure 4. Figure 4: Data collection. (a) Experiment setup. (b) Visual data. The proposed [PITH_FULL_IMAGE:figures/full_fig_p004_4.png]
Figure 7
Figure 7. Figure 7: Baseline method. (a) Workflow of the traditional visuo-haptic [PITH_FULL_IMAGE:figures/full_fig_p005_7.png]
Figure 5
Figure 5. Figure 5: Force inference. (a) Predicted force sequences from inputting [PITH_FULL_IMAGE:figures/full_fig_p005_5.png]
Figure 6
Figure 6. Figure 6: Implicit property distribution in two selected latent features. (a) [PITH_FULL_IMAGE:figures/full_fig_p005_6.png]
Figure 8
Figure 8. Figure 8: Ablation experiments trained on the video-force data and image [PITH_FULL_IMAGE:figures/full_fig_p006_8.png]
Figure 10
Figure 10. Figure 10: Application of property estimation for beach sands. We select three [PITH_FULL_IMAGE:figures/full_fig_p007_10.png]

Discussion (0). Continue with ORCID to comment.

Reference graph

Works this paper leans on

28 extracted references · 22 canonical work pages

  1. [1]

    Mobility of a sphere in vibrated granular media,

    O. Zik, J. Stavans, and Y . Rabin, “Mobility of a sphere in vibrated granular media,” EPL (Europhysics Letters) , vol. 17, no. 4, p. 315, 1992

  2. [2]

    A Haptic-Based Proximity Sensing System for Buried Object in Granular Material

    Z. Zhang, R. Jia, Y . Yan, R. Han, S. Lin, Q. Jiang, L. Zhang, and J. Pan, “A haptic-based proximity sensing system for buried object in granular material,” arXiv preprint arXiv:2411.17083 , 2024

  3. [3]

    Assessment of grain harvest moisture content using machine learning on smartphone images for optimal harvest timing,

    M.-D. Yang, Y .-C. Hsu, W.-C. Tseng, C.-Y . Lu, C.-Y . Yang, M.-H. Lai, and D.-H. Wu, “Assessment of grain harvest moisture content using machine learning on smartphone images for optimal harvest timing,” Sensors, vol. 21, no. 17, p. 5875, 2021

  4. [4]

    Soil moisture measuring techniques and factors affecting the moisture dynamics: A comprehensive review,

    M. W. Rasheed, J. Tang, A. Sarwar, S. Shah, N. Saddique, M. U. Khan, M. Imran Khan, S. Nawaz, R. R. Shamshiri, M. Aziz, et al. , “Soil moisture measuring techniques and factors affecting the moisture dynamics: A comprehensive review,” Sustainability, vol. 14, no. 18, p. 11538, 2022

  5. [5]

    Thermal imagery for rover soil assessment using a multipurpose environmental chamber under simulated mars conditions,

    R. Castilla-Arquillo, A. Mandow, C. J. P ´erez-del Pulgar, C. ´Alvarez- Llamas, J. M. Vadillo, and J. Laserna, “Thermal imagery for rover soil assessment using a multipurpose environmental chamber under simulated mars conditions,” IEEE Transactions on Instrumentation and Measurement, 2023

  6. [6]

    Risk assessment of geological landslide hazards using d-insar and remote sensing,

    J. Zhong, Q. Li, J. Zhang, P. Luo, and W. Zhu, “Risk assessment of geological landslide hazards using d-insar and remote sensing,” Remote Sensing , vol. 16, no. 2, p. 345, 2024

  7. [7]

    Inferring the material properties of granular media for robotic tasks,

    C. Matl, Y . Narang, R. Bajcsy, F. Ramos, and D. Fox, “Inferring the material properties of granular media for robotic tasks,” in 2020 ieee international conference on robotics and automation (icra) . IEEE, 2020, pp. 2770–2777

  8. [8]

    Estimating properties of solid particles inside container using touch sensing,

    X. Guo, H.-J. Huang, and W. Yuan, “Estimating properties of solid particles inside container using touch sensing,” in 2023 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS) . IEEE, 2023, pp. 8985–8992

Show all 28 references
  1. [9]

    Slow drag in a granular medium,

    R. Albert, M. Pfeifer, A.-L. Barab ´asi, and P. Schiffer, “Slow drag in a granular medium,” Physical review letters , vol. 82, no. 1, p. 205, 1999

  2. [10]

    Cotracker: It is better to track together,

    N. Karaev, I. Rocco, B. Graham, N. Neverova, A. Vedaldi, and C. Rupprecht, “Cotracker: It is better to track together,” arXiv preprint arXiv:2307.07635, 2023

  3. [11]

    One fling to goal: Environment-aware dynamics for goal- conditioned fabric flinging,

    L. Yang, L. Yang, H. Sun, Z. Zhang, H. He, F. Wan, C. Song, and J. Pan, “One fling to goal: Environment-aware dynamics for goal- conditioned fabric flinging,” arXiv preprint arXiv:2406.14136 , 2024

  4. [12]

    Rigid-soft interactive learning for robust grasping,

    L. Yang, F. Wan, H. Wang, X. Liu, Y . Liu, J. Pan, and C. Song, “Rigid-soft interactive learning for robust grasping,” IEEE Robotics and Automation Letters , vol. 5, no. 2, pp. 1720–1727, 2020

  5. [13]

    Robot cooking with stir-fry: Bimanual non-prehensile manipulation of semi-fluid objects,

    J. Liu, Y . Chen, Z. Dong, S. Wang, S. Calinon, M. Li, and F. Chen, “Robot cooking with stir-fry: Bimanual non-prehensile manipulation of semi-fluid objects,” IEEE Robotics and Automation Letters , vol. 7, no. 2, pp. 5159–5166, 2022

  6. [14]

    Understanding dynamic tactile sensing for liquid property estimation,

    H.-J. Huang, X. Guo, and W. Yuan, “Understanding dynamic tactile sensing for liquid property estimation,” arXiv preprint arXiv:2205.08771, 2022

  7. [15]

    Goats: Goal sampling adaptation for scooping with curriculum reinforcement learning,

    Y . Niu, S. Jin, Z. Zhang, J. Zhu, D. Zhao, and L. Zhang, “Goats: Goal sampling adaptation for scooping with curriculum reinforcement learning,” arXiv preprint arXiv:2303.05193 , 2023

  8. [16]

    Deep visuo-tactile learning: Estimation of tactile properties from images,

    K. Takahashi and J. Tan, “Deep visuo-tactile learning: Estimation of tactile properties from images,” in 2019 International Conference on Robotics and Automation (ICRA) . IEEE, 2019, pp. 8951–8957

  9. [17]

    Edo-net: Learning elastic properties of deformable objects from graph dynamics,

    A. Longhini, M. Moletta, A. Reichlin, M. C. Welle, D. Held, Z. Erickson, and D. Kragic, “Edo-net: Learning elastic properties of deformable objects from graph dynamics,” in 2023 IEEE International Conference on Robotics and Automation (ICRA) . IEEE, 2023, pp. 3875–3881

  10. [18]

    Learning audio feedback for estimating amount and flow of granular material,

    S. Clarke, T. Rhodes, C. G. Atkeson, and O. Kroemer, “Learning audio feedback for estimating amount and flow of granular material,” Proceedings of Machine Learning Research , vol. 87, 2018

  11. [19]

    Uncertainty- aware self-supervised target-mass grasping of granular foods,

    K. Takahashi, W. Ko, A. Ummadisingu, and S.-i. Maeda, “Uncertainty- aware self-supervised target-mass grasping of granular foods,” in 2021 IEEE International Conference on Robotics and Automation (ICRA) . IEEE, 2021, pp. 2620–2626

  12. [20]

    Generation of a tactile-based pouring motion using fingertip force sensors,

    T. Kiyokawa, M. Ding, G. A. G. Ricardez, J. Takamatsu, and T. Oga- sawara, “Generation of a tactile-based pouring motion using fingertip force sensors,” in 2019 IEEE/SICE International Symposium on System Integration (SII). IEEE, 2019, pp. 669–674

  13. [21]

    Learning robotic pow- der weighing from simulation for laboratory automation,

    Y . Kadokawa, M. Hamaya, and K. Tanaka, “Learning robotic pow- der weighing from simulation for laboratory automation,” in 2023 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS). IEEE, 2023, pp. 2932–2939

  14. [22]

    Undulatory swimming in sand: subsurface locomotion of the sandfish lizard,

    R. D. Maladen, Y . Ding, C. Li, and D. I. Goldman, “Undulatory swimming in sand: subsurface locomotion of the sandfish lizard,” science, vol. 325, no. 5938, pp. 314–318, 2009

  15. [23]

    A data-driven approach for fast simulation of robot locomotion on granular media,

    Y . Zhu, L. Abdulmajeid, and K. Hauser, “A data-driven approach for fast simulation of robot locomotion on granular media,” in 2019 international conference on robotics and automation (ICRA) . IEEE, 2019, pp. 7653–7659

  16. [24]

    Local dilation and compaction of granular materials induced by plate drag,

    M. Kobayakawa, S. Miyai, T. Tsuji, and T. Tanaka, “Local dilation and compaction of granular materials induced by plate drag,” Physical Review E, vol. 98, no. 5, p. 052907, 2018

  17. [25]

    A model for predicting soil-tool interac- tion,

    W. Swick and J. Perumpral, “A model for predicting soil-tool interac- tion,” Journal of Terramechanics , vol. 25, no. 1, pp. 43–56, 1988

  18. [26]

    Adam: A method for stochastic optimiza- tion,

    D. P. Kingma and J. Ba, “Adam: A method for stochastic optimiza- tion,” arXiv preprint arXiv:1412.6980 , 2014

  19. [27]

    Target-free extrinsic calibration of event-lidar dyad using edge correspondences,

    W. Xing, S. Lin, L. Yang, and J. Pan, “Target-free extrinsic calibration of event-lidar dyad using edge correspondences,” IEEE Robotics and Automation Letters, 2023

  20. [28]

    Polymer-based self- calibrated optical fiber tactile sensor,

    W. Chen, Y . Yan, Z. Zhang, L. Yang, and J. Pan, “Polymer-based self- calibrated optical fiber tactile sensor,” in 2023 IEEE/RSJ International Conference on Intelligent Robots and Systems (IROS) . IEEE, 2023, pp. 10 197–10 203

Pith tools

Reviewed August 11, 2026 · model on record in the stance chip above.