Traversing highly-varied terrain : enhanced contacts for human-scale robot locomotion

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Abstract/Contents

Abstract
There have been continuous efforts over the last few decades to create robots that can work in complex and unstructured environments including rocky terrain or rubble in the aftermath of an earthquake or other disaster. Relevant applications range from search and rescue operations to planetary exploration. Small robots have advantages for vertical climbing, but it is hard for them to traverse obstacles beyond their body dimensions. Human-scale robots equipped with legs and arms have the potential to better negotiate rough piles of debris, but it becomes challenging for them to maintain balance and achieve traction on irregular surfaces. This thesis investigates the physical interaction of robot appendages with hard, rough surfaces and presents two particular climbing aids inspired by human hiking and rock climbing activities. The first is a smart hiking staff for human robots. It allows additional contacts to be applied outside the normal reach of hands and feet of a robot. The staff also contains a robust, lightweight force sensor to measure ground reaction forces and torques. An active sensing method is developed based on the force sensor to characterize the terrain information, including contact orientation and coefficient of surface friction to prevent slips. The second climbing aid is an end-effector covered with arrays of spines. The utilization of spines is inspired by micro-spines found on insects' legs. By softly conforming to rough terrain, each spine catches and exploits microscopic surface features to generate highly-frictional and adhesive contact, which is more robust than normal point contact with a single hard object. Load sharing systems ensure that the contributions of many individual spines combine, so that the hand or foot of a human-sized robot can exert forces on the order of hundreds of Newtons parallel to the surface for climbing. The spine arrays can also be integrated into multi-fingered hands that wrap around convex features and perform gripping techniques commonly-used by human rock climbers, allowing the robot to apply robust contacts on highly-varied terrain and even tensile forces perpendicular to the surface.

Description

Type of resource text
Form electronic; electronic resource; remote
Extent 1 online resource.
Publication date 2017
Issuance monographic
Language English

Creators/Contributors

Associated with Wang, Shiquan
Associated with Stanford University, Department of Mechanical Engineering.
Primary advisor Cutkosky, Mark R
Thesis advisor Cutkosky, Mark R
Thesis advisor Khatib, Oussama
Thesis advisor Waldron, Kenneth J
Advisor Khatib, Oussama
Advisor Waldron, Kenneth J

Subjects

Genre Theses

Bibliographic information

Statement of responsibility Shiquan Wang.
Note Submitted to the Department of Mechanical Engineering.
Thesis Thesis (Ph.D.)--Stanford University, 2017.
Location electronic resource

Access conditions

Copyright
© 2017 by Shiquan Wang
License
This work is licensed under a Creative Commons Attribution Non Commercial 3.0 Unported license (CC BY-NC).

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