PUBLICITY INFORMATION FOR: K. Autumn, M. Sitti, Y. Liang, A. Peattie, W. Hansen, S. Sponberg, T. Kenny, R. Fearing, J. Israelachvili, R.J. Full. 2002 (In press). Evidence for van der Waals adhesion in gecko setae. Proceedings of the National Academy of Sciences. Click here for press release Please note: The content of any press release and related material is embargoed until 5 p.m. Eastern Standard Time on Mon 26 August 2002. For more information, see embargo policy for PNAS. Wire services stories must always carry the embargo time at the head of each item, and may not be sent out more than 24 hours before that time. For Questions on Embargo Policy contact: PNAS Communications Officer Jill Locantore at 202-334-1310: jlocantore@nas.edu, or PNASnews@nas.edu

The Gecko Team Biology Engineering Synergy

Lead author/Biomechanics Prof. Kellar Autumn, Lewis & Clark College, Portland, Oregon; Phone: 503-768-7502 (Office); 503-804-2342 (Mobile) autumn@lclark.edu; http://www.lclark.edu/~autumn/ Microfabrication engineering Prof. Ronald S. Fearing, UC Berkeley; 510-642-9193; ronf@haydn.berkeley.edu Dr. Metin Sitti. sitti@tudor.EECS.Berkeley.EDU Chemical engineering Prof. Jacob N. Israelachvili, UC Santa Barbara. jacob@squid.ucsb.edu Mechanical engineering/MEMS force sensing Prof. Thomas Kenny, Stanford University. kenny@cdr.stanford.edu Biomechanics Prof. Robert J. Full, UC Berkeley; 510-642-9896; rjfull@socrates.berkeley.edu Supported by DARPA/CBBS

Summary

The Gecko Team's paper in PNAS:

1. Provides the first direct experimental verification for a van der Waals mechanism of gecko foot-hair adhesion;

2. Predicts foot-hair design based on adhesive theory. Adhesion is enhanced simply by splitting a surface into small protrusions to increase surface density - just what has evolved in nature independently numerous times.

3. Reports the gecko-inspired fabrication of synthetic foot-hair tips that stick. If van der Waals force is the mechanism, then adhesion should depend more on size and shape than on the nature of the surface. Our ability to fabricate artificial foot-hair tips that stick from two different materials strongly supports our experimental and theoretical results. Moreover, our initial fabrication feats open the door to manufacturing the first biologically inspired dry, adhesive microstructures that can have wide-spread application.

Gecko Adhesion Images

ALL IMAGES ARE COPYRIGHTED AND MAY BE USED WITH PERMISSION ONLY.
CONTACT: Dr. Kellar Autumn <autumn@lclark.edu>

Gecko feet (Photo: Paul D. Stewart)	Tokay gecko, spatulae, and synthetic gecko adhesive (SEM by K. Autumn, Photo: M. Moffett)	Gecko foot adhering to GaAs semiconductor, demonstrating van der Waals adhesion (Photo by K. Autumn)
Tokay (Gekko gecko). Photo: M. Moffett.	Gecko Team symbol: Synergy between biology and engineering.	Tokay (Gekko gecko) foot. Photo: M. Moffett.
Tokay (Gekko gecko). Photo: M. Moffett.	RoboGecko designed by iRobot Corp. inspired by Gecko Team research.	Tokay gecko climbing while inverted on glass. Photo: K. Autumn
Gecko setae. (K. Autumn, E. Florance)	Single gecko seta. (K. Autumn, E. Florance)	Spatulae on a single gecko seta. (K. Autumn, E. Florance)
Gecko toe. (K. Autumn, E. Florance)	Spatulae on a single gecko seta. (K. Autumn, E. Florance)	Atomic force microscope (AFM) scan of synthetic gecko spatulae (R. Fearing)

Click here for Autumn et al. Nature 2000 site.