Robotic Materials


2022


Simulating Electrohydraulic Soft Actuator Assemblies Via Reduced Order Modeling
Simulating Electrohydraulic Soft Actuator Assemblies Via Reduced Order Modeling

Hainsworth, T., Schmidt, I., Sundaram, V., Whiting, G. L., Keplinger, C., MacCurdy, R.

SOFT ROBOTICS. IEEE INTERNATIONAL CONFERENCE. 5TH 2022. (RoboSoft 2022), pages: 21-28, Institute of Electrical and Electronics Engineers (IEEE), 2022 IEEE 5th International Conference on Soft Robotics (RoboSoft), April 2022 (conference)

Abstract
Soft robots compliment traditional rigid robots by expanding their capabilities to interact with the physical world. A robot made with compliant, soft materials can benefit from their inherent continuum mechanics to achieve interactions with the environment that a rigid robot may find difficult. This can include grasping delicate objects, navigating through variable terrain, or working alongside humans in a safer manner. The flexible, adaptable nature of soft robots provide these benefits, but they also make predicting their actuated response a difficult, computationally-intensive task. Here we provide a non-linear, reduced order model informed by collected data on hydraulically amplified self-healing electrostatic actuators (HASELs). With this reduced order model, we simulate robots comprised of multiple actuators in an effort to rapidly evaluate potential design candidates without the need for time-consuming manufacturing. The simulation leverages a reduced-order model of HASELs based on a parallel mass spring damper (MSD) representation, made of two non-linear springs, and a damper; this data-driven parameter identification aids model fidelity. We construct a robotic manipulator actuated via six HASELs and show that the simulations driven by the non-linear MSD models accurately predict the robot's physical behavior on a macro scale. While this work focuses on a specific actuator type, the approach shown here could be extended to other linearly expanding soft actuators. Using this method, soft robotic assemblies actuated via HASELs can be rapidly evaluated in simulation before a laborious manufacturing process, which in turn will allow for faster design iterations to create more effective robots.

link (url) DOI [BibTex]

2022

link (url) DOI [BibTex]

2021


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Electriflow: Augmenting Books With Tangible Animation Using Soft Electrohydraulic Actuators

Purnendu, , Novack, S., Acome, E., Alistar, M., Keplinger, C., Gross, M. D., Bruns, C., Leithinger, D.

In SIGGRAPH ’21: ACM SIGGRAPH 2021 Labs, pages: 8, ACM, New York, NY, Special Interest Group on Computer Graphics and Interactive Techniques Conference (SIGGRAPH 2021), July 2021 (inproceedings)

Abstract
We present Electriflow: a method of augmenting books with tangible animation employing soft electrohydraulic actuators. These actuators are compact, silent and fast in operation, and can be fabricated with commodity materials. They generate an immediate hydraulic force upon electrostatic activation without an external fluid supply source, enabling a simple and self-contained design. Electriflow actuators produce an immediate shape transition from flat to folded state which enabled their seamless integration into books. For the Emerging Technologies exhibit, we will demonstrate the prototype of a book augmented with the capability of tangible animation.

link (url) DOI [BibTex]

2021

link (url) DOI [BibTex]


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Soft Electrohydraulic Actuators for Origami Inspired Shape-Changing Interfaces

Purnendu, , Acome, E., Keplinger, C., Gross, M. D., Bruns, C., Leithinger, D.

In CHI EA ’21: Extended Abstracts of the 2021 CHI Conference on Human Factors in Computing Systems, pages: 377, ACM, New York, NY, Conference on Human Factors in Computing Systems (CHI 2021), May 2021 (inproceedings)

Abstract
In this paper, we present electrohydraulic actuators for origami inspired shape-changing interfaces, which are capable of producing sharp hinge-like bends. These compliant actuators generate an immediate hydraulic force upon electrostatic activation without an external fluid supply source, are silent and fast in operation, and can be fabricated with commodity materials. We experimentally investigate the characteristics of these actuators and present application scenarios for actuating existing objects as well as origami folds. In addition, we present a software tool for the design and fabrication of shape-changing interfaces using these electrohydraulic actuators. We also discuss how this work opens avenues for other possible applications in Human Computer Interaction (HCI).

link (url) DOI [BibTex]

link (url) DOI [BibTex]