Search arXivSearch

arXiv · 2009.08156

Suction-based Soft Robotic Gripping of Rough and Irregular Parts

Abstract

Recently, suction-based robotic systems with microscopic features or active suction components have been proposed to grip rough and irregular surfaces. However, sophisticated fabrication methods or complex control systems are required for such systems, and robust attachment to rough real-world surfaces still remains a grand challenge. Here, we propose a fully soft robotic gripper, where a flat elastic membrane is used to conform and contact parts or surfaces well, where an internal negative pressure exerted on the air-sealed membrane induces the suction-based gripping. 3D printing in combination with soft molding techniques enable the fabrication of the soft gripper. Robust attachment to complex 3D and rough surfaces is enabled by the surface-conformable soft flat membrane, which generates strong and robust suction at the contact interface. Such robust attachment to rough and irregular surfaces enables manipulation of a broad range of real-world objects, such as an egg, lime, and foiled package, without any physical damage. Compared to the conventional suction cup designs, the proposed suction gripper design shows a four-fold increase in gripping performance on rough surfaces. Furthermore, the structural and material simplicity of the proposed gripper architecture facilitates its system-level integration with other soft robotic peripherals, which can enable broader impact in diverse fields, such as digital manufacturing, robotic manipulation, and medical gripping applications.

Explore related subjects

Keep this discovery

Explore connections, maps & timelines

BibTeXRIS

Sukho Song, Dirk-Michael Drotlef, Donghoon Son, Anastasia Koivikko, Metin Sitti. 2020-09-17. Suction-based Soft Robotic Gripping of Rough and Irregular Parts. https://doi.org/10.1002/advs.202100641

Cite the original work for its findings. Save a collection to share your selection of sources.

KEEP EXPLORING

Related papers

RCS angular control with gradient metasurfaces: design and measurement

This letter proposes the design and measurement of a periodic metasurface that achieves anomalous reflection with reduced RCS in a given parasitic direction. A previous study proposed a semi-analytical model to predict the RCS behavior of such a metasurface. However, this first study did not include any experimental exploration to verify the theoretical results. To complete this study, this work presents an experimental validation of the proposed design, with a focus on manufacturing and measurement issues. The synthesis, design specifications, fabrication method and experimental setup are presented and discussed. Measurement results are also examined in detail, highlighting some limitations in metasurfaces RCS measurements. The proposed metasurface effectively achieves the predicted RCS level reduction in the considered parasitic direction. The agreement between simulation and experimental results demonstrates the accuracy of the modelling and the efficiency of the optimisation procedure.

physics.app-ph

Maximum-Power-Transfer Power Coordinates for Fully Coupled Multiport Thévenin Sources

A power-normalized scattering representation is developed at a fixed frequency for a passive linear time-invariant multiport load driven by a fully coupled multiport Thévenin source. The source is obtained by reducing, at the load reference planes, an independent-source network whose suppressed internal impedance is passive, together with an intervening passive matching network. No diagonal-reference, uncoupled-source-channel, reciprocity, or commutation assumption is required. With $R_s=\mathrm{Herm}\{Z_s\}\succ\mathbf{0}$, completing the square in accepted power identifies the available-power current and motivates the coordinates $\mathbf{a}=\frac12R_s^{-1/2}(\mathbf{V}+Z_s\mathbf{I})$, $\mathbf{b}=\frac12R_s^{-1/2}(\mathbf{V}-Z_s^H\mathbf{I})$. They satisfy $\|\mathbf{a}\|_2^2-\|\mathbf{b}\|_2^2=\Re\{\mathbf{I}^H\mathbf{V}\}$ and yield $\mathbf{S}=R_s^{-1/2}(Z_{load}-Z_s^H)(Z_{load}+Z_s)^{-1}R_s^{1/2}$. An exact operator identity establishes passivity--contractivity equivalence and gives excitation-specific, reachable-subspace, and complete conjugate-matching conditions. On the physically reachable incident subspace, singular values characterize the best- and worst-case source-normalized port-reflection TARC, while a restricted Frobenius norm gives the basis-averaged squared TARC. Equal-magnitude phase-only control is formulated separately as a constant-modulus problem, with generator-side constraints mapped through the coupled source network before power normalization. For antenna loads and excitations with $P_{acc}>0$, $P_{rad}/P_{av}=η_{rad}(1-\mathrm{TARC}^2)$, so terminal scattering data alone do not determine radiation efficiency. When $R_s$ is singular, finite available power exists exactly for $\mathbf{E}\in\mathrm{range}(R_s)$, and the construction applies on the positive-resistance support.

physics.app-ph

Bimorph Lithium Niobate Thickness-Shear Overtone Film Bulk Acoustic Resonator

High quality factor ($Q$) and overtone operation enable narrow-linewidth acoustic devices with multiple discrete frequencies in a single cavity. Maintaining both high $Q$ and sufficient electromechanical coupling at higher mode orders remains challenging. Here, we demonstrate a bimorph periodically poled piezoelectric film (P3F) lithium niobate (LN) platform for high-order thickness-shear (TS) overtone excitation. The device comprises a bonded 80-$μ$m-thick single-crystal X-cut LN bimorph with opposite polarizations, patterned top and floating bottom electrodes, and a suspended air cavity. The P3F configuration mitigates charge cancellation from the alternating stress distribution of higher-order TS modes, enabling measurable coupling across a broad sequence of overtones. The thick LN acoustic cavity and increasingly confined high-order mode profiles support low-loss operation. Measured TS overtones extend to 1.75 GHz. At room temperature, representative overtones at 0.77 and 0.89 GHz exhibit 3-dB $Q$ values of 11,338 and 11,917, corresponding to $fQ$ products of $8.74\times10^{12}$ and $1.06\times10^{13}$ Hz, respectively. Cooling from 297 to 12 K systematically enhances $Q$, yielding a peak 3-dB $Q$ of 20,507 at 779 MHz and a maximum $fQ$ product of $1.98\times10^{13}$ Hz at 1.379 GHz. These results establish bimorph P3F LN as a promising platform for high-$Q$, frequency-scalable micro-acoustic resonators in the sub-GHz and low-GHz regimes.

physics.app-ph