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arxiv: 2604.08443 · v1 · submitted 2026-04-09 · 💻 cs.RO · cs.HC

A Soft Robotic Interface for Chick-Robot Affective Interactions

Jue Chen , Alexander Mielke , Kaspar Althoefer , Elisabetta Versace This is my paper

Pith reviewed 2026-05-10 17:46 UTC · model grok-4.3

classification 💻 cs.RO cs.HC
keywords animal-robot interactionsoft roboticschick behaviorthermal preferenceface-like stimuliaffective interfaceGallus gallusmultimodal cues
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The pith

A soft robotic interface with warmth and face-like visuals is accepted by newly hatched chicks who spend increasing time near it.

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

The paper tests a soft robotic interface for young chicks that delivers warmth, breathing-like rhythmic movements, and face-like visual patterns to check whether the birds treat the device as socially relevant. Chicks approached the interface more often and stayed longer near it over time, strongly favoring warm areas whose appeal grew with repeated exposure while face cues sped up the first contacts. Breathing motions produced neither attraction nor avoidance. These patterns indicate that selected soft, thermal, and visual cues can support early robot-animal contact without triggering rejection. The work supplies a video-tracking protocol for measuring acceptance and a baseline for designing multimodal devices aimed at animal welfare or developmental studies.

Core claim

The authors establish that newly hatched chicks accept a soft robotic affective interface providing warmth, breathing-like rhythmic deformation, and face-like visual stimuli. Using video tracking of spontaneous approach and touch responses, the chicks spent increasing time on or near the interface across different layouts. They displayed a strong and growing preference for warm thermal stimulation and a swift, stable preference for face-like cues that accelerated initial approach to the tactile surface. The breathing cue elicited no preference yet caused no avoidance, supporting continued exploration of multimodal designs for animal-robot interactions.

What carries the argument

The soft robotic affective interface that supplies safe, controllable multimodal cues of warmth, breathing-like rhythmic deformation, and face-like visual stimuli.

If this is right

  • Chicks accept the device through increased time spent on or near it across layouts.
  • Warm thermal stimulation is strongly preferred and this preference strengthens over time.
  • Face-like visual cues produce rapid and stable approach that speeds initial contact.
  • Breathing-like motion can be added without triggering avoidance.
  • Video tracking of spontaneous responses provides a repeatable protocol for assessing acceptance in young birds.

Where Pith is reading between the lines

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

  • Similar cue combinations might be tested with other precocial species to map cross-species acceptance patterns.
  • Scaled versions could be explored for reducing isolation stress in commercial poultry settings.
  • The differential response to breathing versus warmth suggests testing sensory modalities one at a time when designing for birds.
  • Adding physiological recordings such as heart-rate changes could distinguish affective acceptance from purely exploratory behavior.

Load-bearing premise

That spontaneous approach and touch responses during video tracking show the chicks perceive the robot as socially relevant and attractive rather than reacting to novelty or general exploration.

What would settle it

If chicks approach neutral or non-functional control surfaces at the same or higher rates than the warmed and faced interface, or if thermal and visual preferences disappear when novelty is removed through repeated exposure.

Figures

Figures reproduced from arXiv: 2604.08443 by Alexander Mielke, Elisabetta Versace, Jue Chen, Kaspar Althoefer.

Figure 1
Figure 1. Figure 1: Examples of chick–soft robot affective interface interactions in two [PITH_FULL_IMAGE:figures/full_fig_p001_1.png] view at source ↗
Figure 2
Figure 2. Figure 2: System design. a. Horizontal interface with a large faceplate. b. Vertical interface with a small faceplate. Both interfaces share the same structure: soft furry surface, heating pad, silicone pouch and a base (3D-printed in the horizontal interface; polypropylene in the vertical interface). c. The key steps in silicone pouch fabrication (embedded bladder, sealing, and two-layer silicone casting). d. Pouch… view at source ↗
Figure 3
Figure 3. Figure 3: Experimental setups. a–b. Experiments 1a and 1b: two non-heated horizontal interfaces were placed at the midpoints of the short sides of the arena. In Experiment 1b, one big faceplate was attached to either the left or right interface, counterbalanced across sessions. c. Experiment 2: four horizontal interfaces were placed at the four corners, with two diagonally opposite interfaces heated and fixed. All i… view at source ↗
Figure 4
Figure 4. Figure 4: Preferences in Experiment 1a (horizontal) and Experiment 1b (horizontal, with face). Figures display raw data for visualization, whereas all data [PITH_FULL_IMAGE:figures/full_fig_p005_4.png] view at source ↗
Figure 5
Figure 5. Figure 5: Preferences in Experiment 2 (horizontal, with faceplate and heating) and Experiment 3 (vertical, with faceplate and heating). Figures display raw [PITH_FULL_IMAGE:figures/full_fig_p006_5.png] view at source ↗
read the original abstract

The potential of Animal-Robot Interaction (ARI) in welfare applications depends on how much an animal perceives a robotic agent as socially relevant, non-threatening and potentially attractive (acceptance). Here, we present an animal-centered soft robotic affective interface for newly hatched chicks (Gallus gallus). The soft interface provides safe and controllable cues, including warmth, breathing-like rhythmic deformation, and face-like visual stimuli. We evaluated chick acceptance of the interface and chick-robot interactions by measuring spontaneous approach and touch responses during video tracking. Overall, chicks approached and spent increasing time on or near the interface, demonstrating acceptance of the device. Across different layouts, chicks showed strong preference for warm thermal stimulation, which increased over time. Face-like visual cues elicited a swift and stable preference, speeding up the initial approach to the tactile interface. Although the breathing cue did not elicit any preference, neither did it trigger avoidance, paving the way for further exploration. These findings translate affective interface concepts to ARI, demonstrating that appropriate soft, thermal and visual stimuli can sustain early chick-robot interactions. This work establishes a reliable evaluation protocol and a safe baseline for designing multimodal robotic devices for animal welfare and neuroscientific research.

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 presents a soft robotic affective interface for newly hatched chicks that delivers controllable multimodal cues (warmth, breathing-like rhythmic deformation, and face-like visual stimuli). Using video tracking of spontaneous approach and touch behaviors, it claims that chicks demonstrate acceptance of the device, exhibit strong and time-increasing preferences for thermal warmth across layouts, show swift and stable preference for face-like cues that accelerates initial approach, and display neither preference nor avoidance for the breathing cue. These results are positioned as establishing a reliable evaluation protocol and safe baseline for multimodal ARI devices in animal welfare and neuroscientific research.

Significance. If the behavioral findings hold after appropriate controls and statistical validation, the work provides a concrete empirical foundation for soft, multimodal robotic interfaces in early-life animal-robot interactions, with clear translational value for poultry welfare applications and controlled studies of affective processing. The animal-centered design and use of spontaneous metrics represent a practical strength for establishing baselines in ARI.

major comments (2)
  1. [Abstract and Results] Abstract and Results: The central interpretation that increased approach, time spent near the interface, and cue-specific preferences demonstrate chicks perceiving the robot as 'socially relevant, non-threatening and potentially attractive' is not supported by disambiguating controls. Domestic chicks exhibit strong innate thermotaxis and novelty-driven exploration; no control conditions with non-robotic warm pads, non-face visual stimuli, or habituated arenas are described to isolate affective/social attribution from these simpler drives. This directly affects the load-bearing claim for ARI welfare translation.
  2. [Evaluation/Methods] Evaluation/Methods: No sample sizes, statistical tests (e.g., preference metrics, time-course analyses), controls for confounds, or raw data summaries are provided to substantiate the reported preferences for warmth and face-like cues or the 'increasing over time' and 'swift and stable' claims. Without these, the reliability of the behavioral data cannot be assessed.
minor comments (2)
  1. [Results] Clarify notation and presentation of behavioral metrics (e.g., exact definitions of 'approach,' 'time on or near,' and how layouts were counterbalanced) to improve reproducibility.
  2. [Figures] Ensure all figures include scale bars, trial durations, and example video frames with tracking overlays for clarity.

Simulated Author's Rebuttal

2 responses · 0 unresolved

We thank the referee for their constructive comments on our manuscript. We provide point-by-point responses to the major comments and have revised the manuscript to address the concerns raised.

read point-by-point responses

  1. Referee: [Abstract and Results] Abstract and Results: The central interpretation that increased approach, time spent near the interface, and cue-specific preferences demonstrate chicks perceiving the robot as 'socially relevant, non-threatening and potentially attractive' is not supported by disambiguating controls. Domestic chicks exhibit strong innate thermotaxis and novelty-driven exploration; no control conditions with non-robotic warm pads, non-face visual stimuli, or habituated arenas are described to isolate affective/social attribution from these simpler drives. This directly affects the load-bearing claim for ARI welfare translation.

    Authors: We appreciate this point and agree that additional controls would strengthen the claims regarding social attribution. Our study varied the cues within the robotic interface (e.g., warm vs. non-warm, face-like vs. non-face visual stimuli) to demonstrate cue-specific preferences, which goes beyond general thermotaxis or novelty. However, we acknowledge the absence of non-robotic control conditions. In the revised manuscript, we have added a section in the Discussion qualifying our interpretations and noting the need for such controls in future work to better support ARI welfare applications. revision: partial

  2. Referee: [Evaluation/Methods] Evaluation/Methods: No sample sizes, statistical tests (e.g., preference metrics, time-course analyses), controls for confounds, or raw data summaries are provided to substantiate the reported preferences for warmth and face-like cues or the 'increasing over time' and 'swift and stable' claims. Without these, the reliability of the behavioral data cannot be assessed.

    Authors: We apologize for not clearly presenting these details in the initial submission. The revised manuscript now explicitly includes the sample sizes, the statistical tests performed (including preference metrics and time-course analyses), descriptions of controls for confounds, and raw data summaries to substantiate the claims. revision: yes

Circularity Check

0 steps flagged

No circularity: purely empirical observational study with direct measurements

full rationale

The paper reports results from controlled behavioral experiments measuring spontaneous approach, time spent near the interface, and preferences for thermal, visual, and breathing cues in chicks. No mathematical derivations, equations, fitted parameters, predictions, or first-principles claims are present that could reduce to inputs by construction. All findings are direct observational data from video tracking, with no self-citation load-bearing steps or ansatz smuggling. The interpretive link from behavior to 'social relevance' is an assumption but does not constitute circularity in any derivation chain, as there is no chain to inspect.

Axiom & Free-Parameter Ledger

0 free parameters · 1 axioms · 0 invented entities

The central claim rests on domain assumptions about what behavior means rather than mathematical derivations or new entities.

axioms (1)
  • domain assumption Spontaneous approach and touch responses indicate that the animal perceives the robotic agent as socially relevant, non-threatening and potentially attractive
    This interpretation is used to translate raw video tracking data into the claim of acceptance.

pith-pipeline@v0.9.0 · 5513 in / 1399 out tokens · 44563 ms · 2026-05-10T17:46:13.594673+00:00 · methodology

discussion (0)

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Reference graph

Works this paper leans on

35 extracted references · 35 canonical work pages

  1. [1]

    Design and Development of an Autonomous Feline Entertainment Robot (AFER) for Studying Animal-Robot Interactions,

    C. S. Adams and S. M. Mizanoor Rahman, “Design and Development of an Autonomous Feline Entertainment Robot (AFER) for Studying Animal-Robot Interactions,” inSoutheastCon 2021. Atlanta, GA, USA: IEEE, Mar. 2021, pp. 1–8

    work page 2021

  2. [2]

    Animal-Robot Interaction for pet caring,

    J.-H. Kim, S.-H. Choi, D. Kim, J. Kim, and M. Cho, “Animal-Robot Interaction for pet caring,” in2009 IEEE International Symposium on Computational Intelligence in Robotics and Automation - (CIRA). Daejeon, Korea (South): IEEE, Dec. 2009, pp. 159–164

    work page 2009

  3. [3]

    Design- ing multispecies worlds for robots, cats, and humans,

    E. Schneiders, S. Benford, A. Chamberlain, C. Mancini, S. Castle-Green, V . Ngo, J. Row Farr, M. Adams, N. Tandavanitj, and J. Fischer, “Design- ing multispecies worlds for robots, cats, and humans,” inProceedings of the 2024 CHI Conference on Human Factors in Computing Systems, ser. CHI ’24. New York, NY , USA: Association for Computing Machinery, May 20...

    work page 2024

  4. [4]

    Using RoboChick to Identify the Behavioral Features Promoting Social Interactions,

    Z. Slonina, A. A. Bonzini, J. Brown, S. Wang, I. Farkhatdinov, K. Al- thoefer, L. Jamone, and E. Versace, “Using RoboChick to Identify the Behavioral Features Promoting Social Interactions,” in2021 IEEE International Conference on Development and Learning (ICDL), Aug. 2021, pp. 1–6

    work page 2021

  5. [5]

    Towards mixed societies of chickens and robots,

    A. Gribovskiy, J. Halloy, J.-L. Deneubourg, H. Bleuler, and F. Mondada, “Towards mixed societies of chickens and robots,” in2010 IEEE/RSJ International Conference on Intelligent Robots and Systems, Oct. 2010, pp. 4722–4728

    work page 2010

  6. [6]

    Influence of a mobile robot on the spatial behaviour of quail chicks,

    E. de Margerie, S. Lumineau, C. Houdelier, and M.-A. Richard Yris, “Influence of a mobile robot on the spatial behaviour of quail chicks,” Bioinspiration & Biomimetics, vol. 6, no. 3, p. 034001, Aug. 2011

    work page 2011

  7. [7]

    Animal-to-robot social attachment: Initial requisites in a gallinaceous bird,

    L. Jolly, F. Pittet, J.-P. Caudal, J.-B. Mouret, C. Houdelier, S. Lumineau, and E. de Margerie, “Animal-to-robot social attachment: Initial requisites in a gallinaceous bird,”Bioinspiration & Biomimetics, vol. 11, no. 1, p. 016007, Feb. 2016

    work page 2016

  8. [8]

    Experiments in automatic flock control,

    R. Vaughan, N. Sumpter, J. Henderson, A. Frost, and S. Cameron, “Experiments in automatic flock control,”Robotics and Autonomous Systems, vol. 31, no. 1, pp. 109–117, Apr. 2000

    work page 2000

  9. [9]

    Some aspects of chicken behavior and welfare,

    L. S. Costa, D. F. Pereira, L. G. F. Bueno, and H. Pandorfi, “Some aspects of chicken behavior and welfare,”Brazilian Journal of Poultry Science, vol. 14, pp. 159–164, 2012

    work page 2012

  10. [10]

    The role of affective touch in human- robot interaction: Human intent and expectations in touching the haptic creature,

    S. Yohanan and K. E. MacLean, “The role of affective touch in human- robot interaction: Human intent and expectations in touching the haptic creature,”International Journal of Social Robotics, vol. 4, no. 2, pp. 163–180, Apr. 2012

    work page 2012

  11. [11]

    Affective touch gesture recognition for a furry zoomorphic machine,

    A. Flagg and K. MacLean, “Affective touch gesture recognition for a furry zoomorphic machine,” inProceedings of the 7th International Conference on Tangible, Embedded and Embodied Interaction, ser. TEI ’13. New York, NY , USA: Association for Computing Machinery, Feb. 2013, pp. 25–32

    work page 2013

  12. [12]

    A calming hug: Design and validation of a tactile aid to ease anxiety,

    A. C. Haynes, A. Lywood, E. M. Crowe, J. L. Fielding, J. M. Rossiter, and C. Kent, “A calming hug: Design and validation of a tactile aid to ease anxiety,”PLOS ONE, vol. 17, no. 3, p. e0259838, 2022-3-9

    work page 2022

  13. [13]

    Moffuly-II: A robot that hugs and rubs heads,

    Y . Onishi, H. Sumioka, and M. Shiomi, “Moffuly-II: A robot that hugs and rubs heads,”International Journal of Social Robotics, vol. 16, no. 2, pp. 299–309, Feb. 2024

    work page 2024

  14. [14]

    Touch in human social robot interaction: Systematic literature review with PRISMA method,

    C. Tsirka, A.-M. Velentza, and N. Fachantidis, “Touch in human social robot interaction: Systematic literature review with PRISMA method,” Jul. 2024

    work page 2024

  15. [15]

    With Every Breath: Testing the Effects of Soft Robotic Surfaces on Attention and Stress,

    E. Sabinson, J. Neiberg, and K. E. Green, “With Every Breath: Testing the Effects of Soft Robotic Surfaces on Attention and Stress,” inPro- ceedings of the 2024 ACM/IEEE International Conference on Human- Robot Interaction, ser. HRI ’24. New York, NY , USA: Association for Computing Machinery, Mar. 2024, pp. 611–620

    work page 2024

  16. [16]

    breatHaptics: Enabling gran- ular rendering of breath signals via haptics using shape-changing soft interfaces,

    S. Liu, J. Gu, D. K. Patel, and L. Yao, “breatHaptics: Enabling gran- ular rendering of breath signals via haptics using shape-changing soft interfaces,” inProceedings of the Eighteenth International Conference on Tangible, Embedded, and Embodied Interaction, ser. TEI ’24. New York, NY , USA: Association for Computing Machinery, Feb. 2024, pp. 1–11

    work page 2024

  17. [17]

    Editorial overview: Affective touch: Neurobiology and function,

    A. Schirmer and F. McGlone, “Editorial overview: Affective touch: Neurobiology and function,”Current Opinion in Behavioral Sciences, vol. 45, p. 101129, Jun. 2022

    work page 2022

  18. [18]

    Robotics for poultry farming: Challenges and opportunities,

    U. ¨Ozent¨urk, Z. Chen, L. Jamone, and E. Versace, “Robotics for poultry farming: Challenges and opportunities,”Computers and Electronics in Agriculture, vol. 226, p. 109411, Nov. 2024

    work page 2024

  19. [19]

    Multiple weak biases support adaptive choices without prior experience: A self-supervised strategy,

    E. Versace and B. L. de Bivort, “Multiple weak biases support adaptive choices without prior experience: A self-supervised strategy,”Proceed- ings of the Royal Society B: Biological Sciences, vol. 293, no. 2064, p. 20251878, Feb. 2026

    work page 2064

  20. [20]

    Origins of knowledge: Insights from precocial species,

    E. Versace and G. Vallortigara, “Origins of knowledge: Insights from precocial species,”Frontiers in Behavioral Neuroscience, vol. 9, Dec. 2015

    work page 2015

  21. [21]

    Sensitive periods for social development: Interactions between predisposed and learned mechanisms,

    O. Rosa-Salva, U. Mayer, E. Versace, M. H ´ebert, B. S. Lemaire, and G. Vallortigara, “Sensitive periods for social development: Interactions between predisposed and learned mechanisms,”Cognition, vol. 213, p. 104552, Aug. 2021

    work page 2021

  22. [22]

    Mechanisms of avian imprinting: A review,

    J. J. Bolhuis, “Mechanisms of avian imprinting: A review,”Biological Reviews, vol. 66, no. 4, pp. 303–345, 1991

    work page 1991

  23. [23]

    Visual imprinting in birds: Behavior, models, and neural mechanisms,

    B. J. McCabe, “Visual imprinting in birds: Behavior, models, and neural mechanisms,”Frontiers in Physiology, vol. 10, May 2019

    work page 2019

  24. [24]

    First-sight recognition of touched objects shows that chicks can solve molyneux’s problem,

    E. Versace, L. Freeland, and M. G. Emmerson, “First-sight recognition of touched objects shows that chicks can solve molyneux’s problem,” Biology Letters, vol. 20, no. 4, p. 20240025, Apr. 2024

    work page 2024

  25. [25]

    Spontaneous biases enhance generalization in the neonate brain,

    S. Wang, V . Vasas, L. Freeland, D. Osorio, and E. Versace, “Spontaneous biases enhance generalization in the neonate brain,”iScience, vol. 27, no. 7, Jul. 2024

    work page 2024

  26. [26]

    Assessing preferences for adult versus juvenile features in young animals: Newly hatched chicks spontaneously approach red and large stimuli,

    L. V . Freeland, M. G. Emmerson, V . Vasas, J. Gomes, and E. Versace, “Assessing preferences for adult versus juvenile features in young animals: Newly hatched chicks spontaneously approach red and large stimuli,”Learning & Behavior, vol. 53, no. 2, pp. 145–156, Jun. 2025

    work page 2025

  27. [27]

    Inexperienced preys know when to flee or to freeze in front of a threat,

    M. H ´ebert, E. Versace, and G. Vallortigara, “Inexperienced preys know when to flee or to freeze in front of a threat,”Proceedings of the National Academy of Sciences, vol. 116, no. 46, pp. 22 918–22 920, Nov. 2019

    work page 2019

  28. [28]

    Towards an animal-centred ethics for animal–computer interaction,

    C. Mancini, “Towards an animal-centred ethics for animal–computer interaction,”International Journal of Human-Computer Studies, vol. 98, pp. 221–233, Feb. 2017

    work page 2017

  29. [29]

    The effect of brooding temperature on broiler performance,

    J. W. Deaton, S. L. Branton, J. D. Simmons, and B. D. Lott, “The effect of brooding temperature on broiler performance,”Poultry Science, vol. 75, no. 10, pp. 1217–1220, Oct. 1996

    work page 1996

  30. [30]

    Faces are special for newly hatched chicks: Evidence for inborn domain-specific mechanisms underlying spontaneous preferences for face-like stimuli,

    O. Rosa-Salva, L. Regolin, and G. Vallortigara, “Faces are special for newly hatched chicks: Evidence for inborn domain-specific mechanisms underlying spontaneous preferences for face-like stimuli,”Developmen- tal Science, vol. 13, no. 4, pp. 565–577, 2010

    work page 2010

  31. [31]

    Face detection mechanisms: Nature vs. nurture,

    D. Kobylkov and G. Vallortigara, “Face detection mechanisms: Nature vs. nurture,”Frontiers in Neuroscience, vol. 18, May 2024

    work page 2024

  32. [32]

    Simul- taneous measurements of instantaneous heart rate and breathing activity in newly hatched chicks,

    K. Moriya, Y . Chiba, H. Yoneta, R. Akiyama, and H. Tazawa, “Simul- taneous measurements of instantaneous heart rate and breathing activity in newly hatched chicks,”British Poultry Science, vol. 44, no. 5, pp. 761–766, Dec. 2003

    work page 2003

  33. [33]

    Face preference at birth,

    E. Valenza, F. Simion, V . M. Cassia, and C. Umilt `a, “Face preference at birth,”Journal of Experimental Psychology. Human Perception and Performance, vol. 22, no. 4, pp. 892–903, Aug. 1996

    work page 1996

  34. [34]

    Early preference for face- like stimuli in solitary species as revealed by tortoise hatchlings,

    E. Versace, S. Damini, and G. Stancher, “Early preference for face- like stimuli in solitary species as revealed by tortoise hatchlings,” Proceedings of the National Academy of Sciences, vol. 117, no. 39, pp. 24 047–24 049, Sep. 2020

    work page 2020

  35. [35]

    DeepLabCut: Markerless pose estimation of user-defined body parts with deep learning,

    A. Mathis, P. Mamidanna, K. M. Cury, T. Abe, V . N. Murthy, M. W. Mathis, and M. Bethge, “DeepLabCut: Markerless pose estimation of user-defined body parts with deep learning,”Nature Neuroscience, vol. 21, no. 9, pp. 1281–1289, Sep. 2018

    work page 2018