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REVIEW 3 major objections 5 minor 30 references

Power-Efficient Actuation for Insect-Scale Autonomous Underwater Vehicles

T0 review · 3 major / 5 minor · reviewed 2026-08-12 · deepseek-v4-flash

Pith's one-line read Sealing an SMA microactuator in a flexible air capsule cuts its underwater power draw by about 91 percent, from roughly 800 mW to about 70 mW, while preserving low-frequency displacement.

desk verdict Solid bench result with an untested durability premise: the 91% underwater power saving for the encapsulated SMA actuator is credible, but the capsule seal's endurance is the load-bearing assumption for the AUV path. read the letter →

arxiv 2411.18001 v2 pith:6BNGZ2RG submitted 2024-11-27 cs.RO

classification cs.RO
keywords micro/nanorobotsactuationaquaticroboticsshape-memoryalloyunderwaterinsect-scaleAUVpowerefficiencyonboardautonomy
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

The paper sets out to establish that a small sealed pocket of air can make shape-memory-alloy (SMA) microactuators nearly as power-efficient underwater as they are in air. The load-bearing number is a drop in average underwater power from about 800 mW for a bare 10-mg actuator to about 70 mW for a 13-mg encapsulated version, a reduction of roughly 91 percent, with comparable low-frequency displacement of around 3 mm. If that measurement holds, the main obstacle to insect-scale autonomous underwater vehicles disappears, because the actuators no longer demand far more power than a tiny onboard battery can supply. The paper also presents the VLEIBot++, a 900-mg swimmer claimed to be the first subgram microswimmer with onboard power, actuation, and computation, swimming up to 18.7 mm/s for about 20 minutes on one charge.

What carries the argument

The central object is the sealed flexible air capsule: a thin (7.5 µm) Kapton membrane that encloses the SMA wire in an annular air pocket. The paper's argument treats this pocket as a passive thermal resistor: because the heat-transfer coefficient of air (about 2 to 250 $\mathrm{W/(m^2{\cdot}K)}$) is much lower than that of water (about 50 to 20{,}000 $\mathrm{W/(m^2{\cdot}K)}$), the air layer keeps the wire's cooling environment near in-air conditions even while submerged, while the thin Kapton wall adds little conduction resistance and blocks water ingress. The feasibility analysis uses a lumped thermal model, $\mathrm{d}T/\mathrm{d}t=(Q_\mathrm{in}-Q_\mathrm{out})/(mC_p)$, with a series resistance network $R_\mathrm{eq}=R_\mathrm{conv}+R_\mathrm{cond}$ for convection through the air pocket, conduction through Kapton, and convection to the external fluid. Simulated temperatures show the nitinol wire crossing its nominal 90 °C transition temperature while the air cavity stays near 20 °C, the mechanistic prediction that the power measurements then confirm.

What would settle it

Immerse a sealed encapsulated actuator for hours to days, cycle it at 1 Hz with 7% PWM and 3.3 V, and monitor average power and displacement; if average power climbs from about 70 mW toward hundreds of milliwatts, or displacement decays, the claimed 91 percent saving is not durable. Instrumenting the capsule interior for humidity or pressure during immersion would directly reveal whether the air pocket is being maintained.

Watch

Extended reading notes

Core claim

The paper's central claim is that wrapping a 10-mg-class SMA microactuator in a 13-mg sealed flexible Kapton air capsule makes its underwater power consumption nearly match its in-air consumption: about 80 mW average in air and about 70 mW underwater at 1 Hz with 7% PWM, versus roughly 800 mW for the bare actuator underwater, a drop of about 91 percent, while displacement output stays around 3 mm at low frequencies. The authors state these measurements are the main contribution. The paper also claims that the VLEIBot++, a 900-mg surface swimmer with two bare SMA actuators, an onboard custom PCB, and an 11-mAh lithium-ion battery, is the first subgram microswimmer with onboard power, actuation, and computation, swimming up to 18.7 mm/s for about 20 minutes on one charge. Taken together, the claim is that thermally driven SMA actuation, previously ruled out for underwater robots because water's high heat-transfer coefficient forces roughly 1900 percent more power, becomes energetically compatible with insect-scale onboard batteries.

Load-bearing premise

The load-bearing premise is that the sealed Kapton air capsule stays intact, dry, and at near-atmospheric pressure while the actuator works underwater; if water leaks in or vapor condenses inside, the local heat-transfer coefficient rises toward water's value and the measured 70 to 80 mW power level would not persist.

Editorial extensions

If this is right

  • A submerged swimmer using two encapsulated actuators would draw roughly 140 to 160 mW total, which fits the same 11-mAh, 507-mg battery budget that currently gives the VLEIBot++ about 20 minutes of surface operation.
  • The 3 to 4 V excitation and simple MOSFET PWM electronics already used in air can drive the encapsulated actuator underwater, so no high-voltage or high-power drive stage is needed.
  • The air-pocket strategy applies generally to thermally driven microactuators: any device whose power loss is dominated by convective cooling can be made medium-independent by enclosing the hot element in a low-heat-transfer gas layer.
  • A fully submerged VLEIBot++-class robot becomes a realistic next step once buoyancy and hull sealing are adapted, because actuation is no longer the energy bottleneck.
  • Because low-frequency displacement is comparable in air and water, control and propulsion methods developed for the surface swimmer should transfer to an underwater version.

Reading between the lines

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

  • A next test the paper does not report is long-duration immersion: the flexible silicone and cyanoacrylate seals are the components to watch, since any water ingress or internal condensation would raise the local heat-transfer coefficient and erase the 91 percent saving.
  • The reported experiments cover 1 to 5 Hz at low duty cycles; an untested extrapolation is that higher operating frequencies could let the internal air pocket accumulate heat and limit actuation speed, because the capsule also slows heat rejection.
  • The same encapsulation concept could be adapted to other thermally driven microactuators, such as bimorph or other SMA devices, wherever convective cooling dominates power draw.
  • Integrating the encapsulated actuator into a VLEIBot++-style platform would test the full AUV concept; a plausible outcome is a fully submerged swimmer with comparable speed but shorter endurance due to added drag and sealing mass.
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Editorial analysis

A structured set of objections, weighed in public.

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

Referee Report

3 major / 5 minor

Summary. The paper reports two contributions. First, it presents the VLEIBot++, a 900-mg autonomous surface swimmer with an onboard 11-mAh Li-Ion battery and custom PCB, which swims for about 20 minutes and reaches speeds up to 18.7 mm/s (0.46 Bl/s); the authors claim this is the first subgram microswimmer with onboard power, actuation, and computation. Second, to address the high underwater power consumption of bare SMA actuators, the paper introduces a 13-mg encapsulated SMA actuator in which the SMA wire is enclosed in a sealed flexible Kapton air capsule. The central measured result is that this encapsulated actuator consumes about 80 mW average power in air and about 70 mW underwater at 1 Hz, 7% PWM, compared with about 800 mW for a bare 10-mg SMA actuator underwater, a roughly 91% reduction, while producing comparable low-frequency displacement around 3 mm. The paper also presents a lumped thermal model used as a design rationale for the air-capsule concept.

Significance. If the measured power reduction is robust and the air capsule remains intact, dry, and inflated during realistic underwater operation, the result is a meaningful step toward insect-scale autonomous underwater vehicles, because it brings SMA actuation within the energy budget of a sub-gram onboard battery. The strength of the paper is that the 91% figure is an empirical measurement based on five repeated runs per operating point, not a prediction of a tuned model, and the thermal simulation is used only as a feasibility check. The main limitations are that the quantitative comparison between bare and encapsulated actuators is not fully controlled in terms of mechanical output, and the durability of the adhesive-sealed flexible capsule under prolonged immersion, thermal cycling, and hydrostatic pressure is untested. These gaps currently make the AUV-relevant claim conditional rather than demonstrated.

major comments (3)
  1. [Section 3.2, Power Characterization; Figs. 4 and 7] The central 91% underwater power reduction is asserted on the basis that the encapsulated actuator produces 'output displacements comparable to those generated by the tested bare SMA-based actuator,' but no quantitative displacement values, overlays of the displacement traces, or uncertainties are reported. The displacement traces in Figs. 4(d)-(e) and 7(d)-(e) come from different actuators and media and are never directly compared. Because the fair comparison of actuation efficiency requires equal mechanical output (stroke, and ideally work or force), the paper should report the measured displacement amplitudes and their variability for both actuators at the operating points used for the power comparison, or restrict the claim to a measured power difference at a stated, matched displacement.
  2. [Section 3.2, Fabrication Step 4 and following text] The underwater power measurement is a short-term bench test; the paper reports no long-duration immersion, no repeated thermal cycling (the SMA reaches about 90 C each pulse), and no hydrostatic pressure testing of the sealed Kapton capsule. The capsule is explicitly flexible and sealed with flexible silicone adhesive and CA glue, so even modest depth could compress the internal air volume or stress the seams, and any water ingress would raise the local heat-transfer coefficient and invalidate the measured 70 mW level. Since the abstract and conclusions claim a 'path towards the creation of insect-scale AUVs,' this durability premise is load-bearing and currently unsupported. The authors should either add endurance tests (e.g., hours-long submersion, hundreds of actuation cycles, and pressure tests at relevant depths) or explicitly scope the claims to short-term, near-surface bench demonstrations.
  3. [Section 3.1 and 3.2, Figs. 4 and 7] The paper reports the key power values only as 'on the order of' quantities and does not provide numerical means and standard deviations for the five repeated measurements per operating point, even though the figure captions state that ESDs were computed and displayed. For a quantitative claim of 'about 91% reduction' from 800 mW to 70 mW, the exact values and error bars should be given in the text or in a table. Without these numbers, the reader cannot assess the run-to-run variability or the statistical significance of the difference between the bare and encapsulated actuators.
minor comments (5)
  1. [Abstract and Section 3.2] The abstract states the encapsulated actuator consumes 'approximately 80 mW on average' in both air and water, while the Section 3.2 text reports about 80 mW in air and about 70 mW underwater; these numbers should be reconciled for consistency.
  2. [Section 2.2] The text describes the swimming experiments as 'feedforward-controlled' but the tests are presented as open-loop with a fixed PWM pattern; the terminology should be made consistent and clear.
  3. [Section 3.1] The phrase 'five 52-A WG conductors' appears to contain a typo; it should likely read '52-AWG' or another gauge designation.
  4. [Section 3.2, Heat-Transfer Analysis] The thermal model uses assumed heat-transfer coefficients and a drive current of 125 mA without a sensitivity analysis or experimental validation; since the model is a design rationale and not the source of the measured power claim, this is a presentation issue, but a brief sensitivity discussion would clarify the model's limited role.
  5. [Introduction and Section 2.2] The claim of being the 'first subgram microswimmer with onboard power, actuation, and computation' would benefit from an explicit comparison with prior untethered aquatic microrobots, including those cited as tethered or externally actuated, to make the novelty claim verifiable.

Circularity Check

0 steps flagged · score 0.0 of 10

No significant circularity; the central power-efficiency claims are direct measurements, not derived from or fitted to the model.

full rationale

The paper's main contribution, the 91% underwater power reduction of the encapsulated actuator, is an empirical comparison of measured average powers: about 800 mW for the bare actuator underwater (Section 3.1) versus about 70 mW for the encapsulated actuator underwater (Section 3.2). These values come from instrumentation (current sensor, laser displacement sensor) and are not outputs of the thermal model. The heat-transfer analysis in Section 3.2 is a feasibility rationale using textbook heat-transfer coefficients and geometric assumptions; it is not tuned to reproduce the measured 70-80 mW, and the paper does not claim the model predicts the exact measured power. The displacement-matching protocol (adjusting on-height voltage to obtain comparable ~3 mm displacement) is a standard ceteris paribus experimental design, not a fitted-input-called-prediction step. Prior work by the same authors is cited for the bare SMA actuator technology, but the baseline underwater power consumption is measured in this paper rather than merely imported from a citation. The 'first subgram microswimmer' claim is a literature-status assertion, not a derivation from the paper's own equations. No self-referential or definitional equivalence was found between the claimed results and their inputs.

Assumptions & free parameters 4 free parameters · 5 assumptions · 0 invented entities

The measured headline result is largely self-contained, but the design-prediction story relies on unmeasured thermal coefficients, a simulation current that does not match measured power, and a single prototype. These are assumptions, not invented entities.

free parameters (4)
  • Convective heat-transfer coefficient of the air pocket = 210 W/(m^2 K)
    Assumed in Section 3.2 to estimate R_conv,a in the lumped model; this is at the high end of the gas range and is not measured in the capsule geometry.
  • Convective heat-transfer coefficient of surrounding water = 5000 W/(m^2 K)
    Assumed for R_conv,f in the underwater simulation; actual value for the moving actuator is not measured and could vary with flow and geometry.
  • Simulation drive current = 125 mA
    Chosen as the PWM on-state current; combined with Rsma=8.9 ohm and DC=7%, it gives about 9.7 mW average input, an order of magnitude below the measured 80 mW, so the simulated input is not calibrated to the experiment.
  • Displacement calibration factor = dt/dp = 1.58
    Empirically determined in Section 3.1 to correct laser displacement readings through acrylic and water; affects reported displacement but not power.
assumptions (5)
  • domain assumption The lumped thermal model of Eq. (1) with uniform SMA and air temperatures is valid for this actuator.
    Used in Section 3.2 to justify the capsule design; the Biot number is not checked and the real capsule is not a perfect annulus.
  • domain assumption The Kapton capsule stays sealed and dry during underwater operation.
    The efficiency argument depends on a stable air layer; no long-term leakage, condensation, or pressure tests are reported.
  • domain assumption Stress on the SMA wire is similar in air and water, so response differences are purely thermal.
    Stated in Section 3.2 to attribute the power increase to cooling; mechanical loading and boundary conditions are not measured.
  • standard math Textbook cylindrical conduction and convection resistance equations apply.
    Eq. (3) from [30] is used to estimate R_cond and R_conv.
  • domain assumption The single tested encapsulated actuator is representative of the design.
    Power characterization uses one bare and one encapsulated prototype (five repeated runs each); device-to-device variation is not quantified.

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Cite this review

Pith. "Pith review of Power-Efficient Actuation for Insect-Scale Autonomous Underwater Vehicles." pith.science (2026). https://pith.science/paper/6BNGZ2RG

@misc{pith2026241118001,
  author       = {Pith},
  title        = {Pith review of: Power-Efficient Actuation for Insect-Scale Autonomous Underwater Vehicles},
  year         = {2026},
  howpublished = {\url{https://pith.science/paper/6BNGZ2RG}},
  note         = {Machine review of arXiv:2411.18001}
}
read the original abstract

We present a new evolution of the Very Little Eel-Inspired roBot, the VLEIBot++, a 900-mg swimmer driven by two 10-mg bare high-work density (HWD) actuators, whose functionality is based on the use of shape-memory alloy (SMA) wires. An actuator of this type consumes an average power of about 40 mW during in-air operation. We integrated onboard power and computation into the VLEIBot++ using a custom-built printed circuit board (PCB) and an 11-mAh 3.7-V 507-mg single-cell lithium-ion (Li-Ion) battery, which in conjunction enable autonomous swimming for about 20 min on a single charge. This robot can swim at speeds of up to 18.7 mm/s (0.46 Bl/s) and is the first subgram microswimmer with onboard power, actuation, and computation developed to date. Unfortunately, the approach employed to actuate VLEIBot++ prototypes is infeasible for underwater applications because a typical 10-mg bare SMA-based microactuator requires an average power on the order of 800 mW when operating underwater. To address this issue, we introduce a new 13-mg power-efficient high-performance SMA-based microactuator that can function with similar power requirements (approx. 80 mW on average) and actuation performance (approx. 3 mm at low frequencies) in air and water. This design is based on the use of a sealed flexible air-capsule that encloses the SMA wires that drive the microactuator with the purpose of passively controlling the heat-transfer rate of the thermal system. Furthermore, this new power-efficient encapsulated actuator requires low voltages of excitation (3 to 4 V) and simple power electronics to function. The breakthroughs presented in this paper represent a path towards the creation of insect-scale autonomous underwater vehicles (AUVs).

Figures

Figures reproduced from arXiv: 2411.18001 by the authors.

Figure 1
Figure 1. A swimmer and an actuator. The VLEIBot++ (left), a 900-mg autonomous surface swimmer driven by two 10-mg bare SMA-based actuators; and, a new low-power 13-mg encapsulated HWD SMA-based actuator for underwater operation (right). This new actuator has a length of 15.25 mm, a volume without the capsule of 2.37 mm3 , and a volume with the capsule of 33.02 mm3 . The actuators that drive the VLEIBot++ have a length of 12 … view at source ↗
Figure 2
Figure 2. Design and fabrication of the VLEIBot++. (a) Fabrication process of the robot’s custom-designed PCB. In Step 1, sheets of CuFR4 are etched using laser rasterization in order to remove areas of the Cu-coating and thus create the patterns designed for each side of the PCB. In Step 2, the two sides of the PCB are pin-aligned and adhered together with a sheet of Pyralux adhesive by applying pressure and heat inside a cu… view at source ↗
Figure 3
Figure 3. Open-loop swimming experiments of the VLEIBot [PITH_FULL_IMAGE:figures/full_fig_p006_3.png] view at source ↗
Figures from the paper (4 more)
Figure 4
Figure 4. Figure 4: Power-consumption characterization of bare SMA-based actuator. [PITH_FULL_IMAGE:figures/full_fig_p008_4.png]
Figure 5
Figure 5. Figure 5: Proposed solution for underwater actuation. (a) [PITH_FULL_IMAGE:figures/full_fig_p010_5.png]
Figure 6
Figure 6. Figure 6: Fabrication of SMA-based encapsulated actuator. [PITH_FULL_IMAGE:figures/full_fig_p012_6.png]
Figure 7
Figure 7. Figure 7: Power-consumption characterization of encapsulated SMA-based [PITH_FULL_IMAGE:figures/full_fig_p013_7.png]

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Reference graph

Works this paper leans on

30 extracted references · 30 canonical work pages

  1. [1]

    A New 1-mg Fast Uni- morph SMA-Based Actuator for Microrobotics,

    C. K. Trygstad, X.-T. Nguyen, and N. O. P´ erez-Arancibia, “A New 1-mg Fast Uni- morph SMA-Based Actuator for Microrobotics,” in Proc. IEEE/RSJ Int. Conf. Intell. Robots Syst. (IROS), Detroit, MI, USA, Oct. 2023, pp. 2693–2700. Power-Efficient Actuation for Insect-Scale AUVs 15

  2. [2]

    VLEIBot: A New 45-mg Swimming Microrobot Driven by a Bioin- spired Anguilliform Propulsor,

    E. K. Blankenship, C. K. Trygstad, F. M. F. R. Gon¸ calves, and N. O. P´ erez- Arancibia, “VLEIBot: A New 45-mg Swimming Microrobot Driven by a Bioin- spired Anguilliform Propulsor,” in Proc. IEEE Int. Conf. Robot. Autom. (ICRA), Yokohama, Japan, May 2024, pp. 6014–6021

  3. [3]

    A New 10-mg SMA-Based Fast Bimorph Actuator for Microrobotics,

    C. K. Trygstad, E. K. Blankenship, and N. O. P´ erez-Arancibia, “A New 10-mg SMA-Based Fast Bimorph Actuator for Microrobotics,” in Proc. IEEE/RSJ Int. Conf. Intell. Robots Syst. (IROS), Abu Dhabi, UAE, Oct. 2024, pp. 1349–1356

  4. [4]

    A 5 cm-Scale Piezoelectric Jetting Agile Underwater Robot,

    K. Li, X. Zhou, Y. Liu, J. Sun, X. Tian, H. Zheng, L. Zhang, J. Deng, J. Liu, W. Chen, and J. Zhao, “A 5 cm-Scale Piezoelectric Jetting Agile Underwater Robot,” Adv. Intell. Syst., vol. 5, no. 4, Apr. 2023, Art. no. 2200262

  5. [5]

    Bee+: A 95-mg Four-Winged Insect-Scale Flying Robot Driven by Twinned Unimorph Ac- tuators,

    X. Yang, Y. Chen, L. Chang, A. A. Calder´ on, and N. O. P´ erez-Arancibia, “Bee+: A 95-mg Four-Winged Insect-Scale Flying Robot Driven by Twinned Unimorph Ac- tuators,” IEEE Robot. Automat. Lett., vol. 4, no. 4, pp. 4270–4277, Oct. 2019

  6. [6]

    High- Performance Six-DOF Flight Control of the Bee ++: An Inclined-Stroke-Plane Ap- proach,

    R. M. Bena, X. Yang, A. A. Calder´ on, and N. O. P´ erez-Arancibia, “High- Performance Six-DOF Flight Control of the Bee ++: An Inclined-Stroke-Plane Ap- proach,” IEEE Trans. Robot., vol. 39, no. 2, pp. 1668–1684, Apr. 2023

  7. [7]

    A High-Lift Micro- Aerial-Robot Powered by Low-Voltage and Long-Endurance Dielectric Elastomer Actuators,

    Z. Ren, S. Kim, X. Ji, W. Zhu, F. Niroui, J. Kong, and Y. Chen, “A High-Lift Micro- Aerial-Robot Powered by Low-Voltage and Long-Endurance Dielectric Elastomer Actuators,” Adv. Mat., vol. 34, no. 7, Feb. 2022, Art. no. 2106757

  8. [8]

    Insect-Scale Fast Moving and Ul- trarobust Soft Robot,

    Y. Wu, J. K. Yim, J. Liang, Z. Shao, M. Qi, J. Zhong, Z. Luo, X. Yan, M. Zhang, X. Wang, R. S. Fearing, R. J. Full, and L. Lin, “Insect-Scale Fast Moving and Ul- trarobust Soft Robot,” Sci. Robot., vol. 4, no. 32, Jul. 2019, Art. no. eaax1594

Show all 30 references
  1. [9]

    Soft Microrobotic Transmissions Enable Rapid Ground- Based Locomotion,

    W. Zhou and N. Gravish, “Soft Microrobotic Transmissions Enable Rapid Ground- Based Locomotion,” in Proc. IEEE/RSJ Int. Conf. Intell. Robots Syst. (IROS), Las Vegas, NV, USA, Oct. 2020, pp. 7874–7880

  2. [10]

    SMALLBug: A 30-mg Crawling Robot Driven by a High-Frequency Flexible SMA Microactuator,

    X.-T. Nguyen, A. A. Calder´ on, A. Rigo, J. Z. Ge, and N. O. P´ erez-Arancibia, “SMALLBug: A 30-mg Crawling Robot Driven by a High-Frequency Flexible SMA Microactuator,” IEEE Robot. Automat. Lett., vol. 5, no. 4, pp. 6796–6803, Oct. 2020

  3. [11]

    SMARTI: A 60-mg Steerable Robot Driven by High-Frequency Shape-Memory Alloy Actua- tion,

    R. M. Bena, X.-T. Nguyen, A. A. Calder´ on, and N. O. P´ erez-Arancibia, “SMARTI: A 60-mg Steerable Robot Driven by High-Frequency Shape-Memory Alloy Actua- tion,” IEEE Robot. Automat. Lett., vol. 6, no. 4, pp. 8173–8180, Oct. 2021

  4. [12]

    A Biologically In- spired, Flapping-Wing, Hybrid Aerial-Aquatic Microrobot,

    Y. Chen, H. Wang, E. F. Helbling, N. T. Jafferis, R. Zufferey, A. Ong, K. Ma, N. Gravish, P. Chirarattananonand, M. Kovac, and R. J. Wood, “A Biologically In- spired, Flapping-Wing, Hybrid Aerial-Aquatic Microrobot,” Sci. Robot., vol. 2, no. 11, Oct. 2017, Art. no. eaao5619

  5. [13]

    The Rotational Propulsion Charac- teristics of Scaled-Up Helical Microswimmers With Different Heads and Magnetic Positioning,

    T. Xu, G. Hwang, N. Andreff, and S. R´ egnier, “The Rotational Propulsion Charac- teristics of Scaled-Up Helical Microswimmers With Different Heads and Magnetic Positioning,” in Proc. IEEE/ASME Int. Conf. Adv. Intell. Mechatron. (AIM), Wol- longong, NSW, Australia, Jul. 2013, ...

  6. [14]

    Controlled Propulsion and Cargo Transport of Rotating Nickle Nanowires Near a Patterned Solid Surface,

    L. Zhang, T. Petit, Y. Lu, B. E. Kratochvil, K. E. Peyer, R. Pei, J. Lou, and B. J. Nelson, “Controlled Propulsion and Cargo Transport of Rotating Nickle Nanowires Near a Patterned Solid Surface,” ACS Nano, vol. 4, no. 10, pp. 6228– 6234, Sep. 2010

  7. [15]

    An In-Pipe Wireless Swimming Microrobot Driven by Giant Magnetostrictive Film,

    W. Liu, X. Jia, F. Wang, and Z. Jia, “An In-Pipe Wireless Swimming Microrobot Driven by Giant Magnetostrictive Film,” Sens. Actuators A: Phys., vol. 160, no. 2, pp. 101–108, May 2010

  8. [16]

    Power and Control Autonomy for High-Speed Locomotion With an Insect-Scale Legged Robot,

    B. Goldberg, R. Zufferey, N. Doshi, E. F. Helbling, G. Whittredge, M. Kovac, and R. J. Wood, “Power and Control Autonomy for High-Speed Locomotion With an Insect-Scale Legged Robot,” IEEE Robot. Automat. Lett., vol. 3, no. 2, pp. 987–993, Apr. 2018. 16 C. R. Longwell et al

  9. [17]

    MilliMobile: An Autonomous Battery-Free Wireless Microrobot,

    K. Johnson, Z. Englehardt, V. Arroyos, D. Yin, S. Patel, and V. Iyer, “MilliMobile: An Autonomous Battery-Free Wireless Microrobot,” inProc. 29th Annu. Int. Conf. Mob. Comput. Netw. (MOBICOM), Madrid, Spain, Oct. 2023, pp. 1360–1375

  10. [18]

    An Autonomous Untethered Fast Soft Robotic Insect Driven by Low-Voltage Dielectric Elastomer Actuators,

    X. Ji, X. Liu, V. Cacucciolo, M. Imboden, Y. Civet, A. E. Haitami, S. Cantin, Y. Perriard, and H. Shea, “An Autonomous Untethered Fast Soft Robotic Insect Driven by Low-Voltage Dielectric Elastomer Actuators,” Sci. Robot., vol. 4, no. 37, Dec. 2019, Art. no. eaaz6451

  11. [19]

    An 88-Milligram Insect-Scale Au- tonomous Crawling Robot Driven by a Catalytic Artificial Muscle,

    X. Yang, L. Chang, and N. O. P´ erez-Arancibia, “An 88-Milligram Insect-Scale Au- tonomous Crawling Robot Driven by a Catalytic Artificial Muscle,” Sci. Robot., vol. 5, no. 45, Aug. 2020, Art. no. eaba0015

  12. [20]

    Towards Centimeter-Scale Underwater Mobile Robots: An Architecture for Capable µAUVs,

    P. Spino and D. Rus, “Towards Centimeter-Scale Underwater Mobile Robots: An Architecture for Capable µAUVs,” in Proc. IEEE Int. Conf. Robot. Autom. (ICRA), Yokohama, Japan, May 2024, pp. 1484–1490

  13. [21]

    Implicit Coordination for 3D Underwater Collective Behaviors in a Fish-Inspired Robot Swarm,

    F. Berlinger, M. Gauci, and R. Nagpal, “Implicit Coordination for 3D Underwater Collective Behaviors in a Fish-Inspired Robot Swarm,” Sci. Robot., vol. 6, no. 50, Jan. 2021, Art. no. eabd8668

  14. [22]

    A Mod- ular Dielectric Elastomer Actuator to Drive Miniature Autonomous Underwater Vehicles,

    F. Berlinger, M. Duduta, H. Gloria, D. Clarke, R. Nagpal, and R. Wood, “A Mod- ular Dielectric Elastomer Actuator to Drive Miniature Autonomous Underwater Vehicles,” in Proc. IEEE Int. Conf. Robot. Autom. (ICRA), Brisbane, Australia, May 2018, pp. 3429–3435

  15. [23]

    Fish-Like Three-Dimensional Swimming With an Autonomous, Multi-Fin, and Biomimetic Robot,

    F. Berlinger, M. Saadat, H. Haj-Hariri, G. V. Lauder, and R. Nagpal, “Fish-Like Three-Dimensional Swimming With an Autonomous, Multi-Fin, and Biomimetic Robot,” Bioinspir. Biomim., vol. 16, no. 2, Mar. 2021, Art. no. 026018

  16. [24]

    Centimeter-Scale Submarine Robot for Monitoring Coral Reef Ecosystem,

    Z. Li, Y. Zhang, S. He, X. Zhu, T. Wei, and C. Hu, “Centimeter-Scale Submarine Robot for Monitoring Coral Reef Ecosystem,” in Proc. IEEE Int. Conf. Mechatron. Autom. (ICMA), Tianjin, China, Aug. 2024, pp. 345–350

  17. [25]

    Bio-Inspired Aquatic Robotics by Untethered Piezohydroe- lastic Actuation,

    L. Cen and A. Erturk, “Bio-Inspired Aquatic Robotics by Untethered Piezohydroe- lastic Actuation,” Bioinsp. Biomim., vol. 8, no. 1, Mar. 2013, Art. no. 016006

  18. [26]

    A Versatile Jellyfish- Like Robotic Platform for Effective Underwater Propulsion and Manipulation,

    T. Wang, H. Joo, S. Song, W. Hu, C. Keplinger, and M. Sitti, “A Versatile Jellyfish- Like Robotic Platform for Effective Underwater Propulsion and Manipulation,” Sci. Adv., vol. 9, no. 15, p. Art. no. eadg0292, Apr. 2023

  19. [27]

    Biomimetic Vortex Propulsion: To- ward the New Paradigm of Soft Unmanned Underwater Vehicles,

    F. Giorgio-Serchi, A. Arienti, and C. Laschi, “Biomimetic Vortex Propulsion: To- ward the New Paradigm of Soft Unmanned Underwater Vehicles,” IEEE/ASME Trans. Mechatron., vol. 18, no. 2, pp. 484–493, Apr. 2013

  20. [28]

    Jellyfish Inspired Unmanned Underwater Vehicle,

    A. Villanueva, S. Bresser, S. Chung, Y. Tadesse, and S. Priya, “Jellyfish Inspired Unmanned Underwater Vehicle,” in Proc. Electroactive Polym. Actuators Devices (EAPAD), San Diego, CA, USA, Apr. 2009, Art. no. 72871G

  21. [29]

    Life at Low Reynolds Number,

    E. M. Purcell, “Life at Low Reynolds Number,” Amer. J. Phys., vol. 45, no. 1, pp. 3–11, Jan. 1977

  22. [30]

    Y. A. C ¸ engel and A. J. Ghajar,Heat and Mass Transfer. New York, NY, USA: McGraw-Hill Education, 2015

Pith tools

Reviewed August 12, 2026 · model on record in the stance chip above.