Design and modeling of soft growing robots

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Abstract/Contents

Abstract
Soft and bioinspired robots often take inspiration from the forms and behaviors of organisms found in nature. Robots have been designed that imitate caterpillars, amoebas, elephants, octopuses, and more, leveraging the adaptability of the organism's features. Yet few designs have considered the behavior of continuous, indeterminate growth seen in plants and some cells. This dissertation examines one such design, a soft robot that extends from the tip using a continuous stream of material everted by internal pressure, allowing the robot to increase in length. This robot essentially grows by adding new material at the tip. Because artificial growth in this form is relatively unstudied, this thesis focuses on the design, modeling, and application of the robot in order to understand the benefits and constraints in a system like this. We first looked at growth as a new degree of freedom. Unlike other forms of movement, growth is achieved by transporting new material to the tip so that it can be added to the length. To understand this difference, we develop a quasi-static model relating the driving force to the resulting growth. We show that environment friction has little to no effect on growth and that cost of material transport is a function of the previous path. Building on this model, we then demonstrate two key capabilities of growth: movement through constrained, sticky, or slippery environments and construction of usable structures to transport materials, guide tools, or create supports. Next, we consider shape change of the robot and develop a new kinematic model derived from geometric constraints that describes the robot motion and body shape given the shape of a tendon actuator. We validate the model on static and active shapes, and show how the model can be used to design actuators to match a target shape. Finally, we use the learned models and features of robotic growth to inform the design of soft growing robots for reconfigurable and deployable antennas. We use robotic growth to create a monopole antenna can change frequency by changing its length, and we create polarization change in a helical antenna using tendon actuation.

Description

Type of resource text
Form electronic resource; remote; computer; online resource
Extent 1 online resource.
Place California
Place [Stanford, California]
Publisher [Stanford University]
Copyright date 2019; ©2019
Publication date 2019; 2019
Issuance monographic
Language English

Creators/Contributors

Author Blumenschein, Laura Helen
Degree supervisor Okamura, Allison
Thesis advisor Okamura, Allison
Thesis advisor Cutkosky, Mark R
Thesis advisor Follmer, Sean
Thesis advisor Hawkes, Elliot
Degree committee member Cutkosky, Mark R
Degree committee member Follmer, Sean
Degree committee member Hawkes, Elliot
Associated with Stanford University, Department of Mechanical Engineering.

Subjects

Genre Theses
Genre Text

Bibliographic information

Statement of responsibility Laura H. Blumenschein.
Note Submitted to the Department of Mechanical Engineering.
Thesis Thesis Ph.D. Stanford University 2019.
Location electronic resource

Access conditions

Copyright
© 2019 by Laura Helen Blumenschein
License
This work is licensed under a Creative Commons Attribution Non Commercial 3.0 Unported license (CC BY-NC).

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