Developing Design Guidelines for Improved Gecko Inspired Dry Adhesive Performance

• Author / Creator

  Bschaden, Benjamin Simon

• This work provides a guideline for gecko inspired dry adhesive design and simulation. Mechanical property testing for several polymers commonly used in gecko adhesives (Kraton G1657 thermoplastic elastomer, ST-1060, and ST-1087 polyurethane elastomers) allowed hyperelastic and viscoelastic material models to be fitted. These parameters were implemented in a finite element simulation of a single adhesive fiber. The simulation was further improved over previously published models by developing a frictional cap interface boundary condition.
  The simulation was verified by contrasting the results obtained by testing isolated fibers. Adhesion results from a single fiber tests system developed demonstrated that all materials exhibit the Mullins effect, with significant softening after one elongation. Future designs requiring durability are therefore recommended to have lower aspect ratios, limiting the maximum strain in the fiber. Based on experimental observations, a summary is provided to select appropriate boundary conditions based on the specifications of the adhesive.

• Subjects / Keywords

  • Gecko
  • Adhesion
  • Hyperelastic
  • Friction
  • Viscoelastic
  • Simulations

• Graduation date

  Spring 2014

• Type of Item

  Thesis

• Degree

  Master of Science

• DOI

  https://doi.org/10.7939/R3GM4X

• License

  This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.