Bernoulli grip

Summary

A Bernoulli grip uses airflow to adhere to an object without physical contact.[1] Such grippers rely on the Bernoulli airflow principle. While an accelerating, increasing speed, airstream has a low downstream static pressure, the sharp turn from linear to radial flow is the cause of a region of very low pressure around the blower exit hole. This is the cause of a net force on the object in the direction normal to the side with higher local pressure. A Bernoulli gripper takes advantage of this by maintaining this negative pressure at the gripper face compared to the ambient pressure below the sample, while maintaining an air gap between the gripper and the object being held.

The flow of air causes a lifting force on the object, allowing for non-contact adhesion

Applications edit

Commercially available Bernoulli grips are commonly used to handle rigid sheet like material such as silicon wafers in circuit board manufacturing, or photovoltaic cell components.[2][3] Since the grip is contactless, this form of gripping lends itself to handling sterile material to prevent chemical and/or biological contamination. Research has been done into using Bernoulli grippers to transport sample sheet foodstuffs in a food processing context,[1] although this work found difficulties as the flexible foods would vibrate against the gripper, deforming and alternately blocking the gripper and/or being blown away from the airway. The Bernoulli grip is also being investigated as a non-contact adhesion mechanism for wall climbing robots.[4]

References edit

  1. ^ a b "Airflow (Bernoulli) Grippers for Flat Sheet Foods" (PDF). Food Refrigeration & Process Engineering Research Centre, The Grimsby Institute of Further & Higher Education. Retrieved 25 May 2011.
  2. ^ Brun, X.F.; Melkote, S.N. (May 2006). "Evaluation of Handling Stresses Applied to EFG Silicon Wafer using a Bernoulli Gripper". 2006 IEEE 4th World Conference on Photovoltaic Energy Conference. Waikoloa, HI: George W. Woodruff Sch. of Mech. Eng.; Georgia Inst. of Technol., Atlanta, GA. pp. 1346–1349. doi:10.1109/WCPEC.2006.279680. ISBN 1-4244-0017-1.
  3. ^ Osborne, Mark (8 February 2010). "New Product: Bernoulli Gripper from Festo enables 'contactless handling'". PVTech.
  4. ^ Ackerman, Evan (24 May 2011). "Robot Uses Supersonic Jets of Air to Stick to Almost Anything". IEEE Spectrum. Retrieved 25 May 2011.