Title page for ETD etd-10012012-012241


Type of Document Dissertation
Author Zhang, Zhiye
Author's Email Address zzy00@vt.edu
URN etd-10012012-012241
Title Modeling, Analysis, and Experiments of Inter Fiber Yarn Compaction Effects in Braided Composite Actuators
Degree PhD
Department Aerospace and Ocean Engineering
Advisory Committee
Advisor Name Title
Philen, Michael K. Committee Chair
Kapania, Rakesh K. Committee Member
Patil, Mayuresh J. Committee Member
Priya, Shashank Committee Member
Keywords
  • Braided Composite Actuators
  • Variable Stiffness Structures
  • Compaction Model
  • Smart Materials
Date of Defense 2012-09-14
Availability unrestricted
Abstract
The braided composite actuator is a pressure-driven muscle-like actuator capable of large displacements as well as large blocking forces. It consists of an elastomeric tube reinforced by a sleeve braided by high performance fibers.

In addition to the actuation properties, this actuator can also exhibit a large change in stiffness through simple valve control when the working fluid has a high bulk modulus. Several analytical models have been previously developed that capture the geometrical and material nonlinearities, the compliance of the inner liner, and entrapped air in the fluid. The inter fiber yarn compaction in the fiber layer, which is shown to reduce the effective closed-valve stiffness, is studied. A new analytical model for uniformly deformed actuators is developed to capture the compaction effect. This model considers the inter fiber yarn compaction effect and the fiber extensibility as well as the material and geometric nonlinearities. Analysis and experimental results demonstrate that the new compaction model can improve the prediction of the response behavior of the actuator.

The compaction model is improved by considering the yarn bending stiffness. The governing equations are derived and the solution algorithm is presented.

Files
  Filename       Size       Approximate Download Time (Hours:Minutes:Seconds) 
 
 28.8 Modem   56K Modem   ISDN (64 Kb)   ISDN (128 Kb)   Higher-speed Access 
  Zhang_Z_D_2012.pdf 2.99 Mb 00:13:50 00:07:07 00:06:13 00:03:06 00:00:15

Browse All Available ETDs by ( Author | Department )

dla home
etds imagebase journals news ereserve special collections
virgnia tech home contact dla university libraries

If you have questions or technical problems, please Contact DLA.