Design and analysis of jammable granular systems

Jamming--the mechanism by which granular media can transition between liquid-like and solid-like states-has recently been demonstrated as a variable strength and stiffness mechanism in a range of applications. As a low-cost and simple means for achieving tunable mechanical properties, jamming has been used in systems ranging from architectural to medical ones. This thesis explores the utility of jamming for robotic manipulation applications, both at a fundamental level of understanding how granular properties affect the performance of jammed systems, and at a more applied level of designing functional robotic components. Specifically, the purpose of this thesis was to enable engineers to design jammable robotic systems in a principled manner. Three parallel yet related studies were conducted to work towards this goal. First, an experimental analysis was conducted to determine whether the bulk shear strength of granular systems can be correlated with grain properties-such as ones concerning shape, size distribution, and surface texture-extracted from 2D silhouettes of grains. Second, a novel medium composed of a mixture of hard and soft spheres was proposed to achieve variable strength and stiffness properties as a function of confining pressure; experimental analysis was conducted on this system with not only varying confining pressures but also varying mixing ratios of hard and soft spheres. Finally, the design and analysis of a novel jammable robotic manipulator-with the goal of maximizing both the strength and articulation of the system-is presented.

Department dc:contributor.department

Massachusetts Institute of Technology. Department of Mechanical Engineering.

Grantor dc:publisher

Massachusetts Institute of Technology

Year dc:date.issued

2013

Author dc:creator

• Cheng, Nadia G. (Nadia Gen San)

Advisor dc:contributor.advisor

• Karl Iagnemma and Anette Hosoi.

• Mechanical Engineering.

Statement dc:rights

• M.I.T. theses are protected by copyright. They may be viewed from this source for any purpose, but reproduction or distribution in any format is prohibited without written permission. See provided URL for inquiries about permission.

Licence dc:rights.uri

• http://dspace.mit.edu/handle/1721.1/7582

Language dc:language.iso

eng

Handle dc:identifier.uri

http://hdl.handle.net/1721.1/81695

OAI identifier oai:identifier

oai:dspace.mit.edu:1721.1/81695