Date of Graduation

Summer 2015

Document Type

Honors Research Project

Degree Name

Bachelor of Science



Research Sponsor

Dr. Peter H. Niewiarowski

First Reader

Dr. Peter H. Niewiarowski

Second Reader

Dr. Ali Dhinojwala


In an effort to better understand the fascinating gecko adhesive system, scientists have long tested the abilities of the gecko in controlled conditions that mimic the gecko’s native environment. The effects of humidity, environmental temperature, and exposure to water have all been tested. Roughness, however has not been studied in great detail. Surfaces of varying roughnesses are all over the gecko’s natural environment. We tested geckos on hydrophilic silicon carbide sandpapers of varying roughnesses in both air and water to attempt to better study the effects of roughness on gecko adhesion. When tested on the rougher (1 µm) surface, the geckos shear adhesive pull-off force was significantly larger than on the less rough (0.5 µm) surface. Finally, we tested the effect of treatment (air or water) on the rough surfaces and found that there was no significant effect on adhesion when being exposed to water or air on a rough surface. There was a non-significant trend for the difference between the two roughnesses to be larger in water than in air, but sample sizes and statistical power to test this effect were low.