|The soft adhesion-based
gripping system holds a pair
of cherry tomatoes weighing
(Credit: Sukho Song)
Researchers at Carnegie Mellon University and Max Planck Institute for Intelligent Systems have developed a soft gripping system that uses differential air pressure and a gecko-inspired adhesive for exceptional bonding to three-dimensional objects. The findings were published in Proceedings of the National Academy of Sciences recently.
Capable of Strong and Reversible Adhesion
A soft gripping system capable of strong and reversible adhesion to non-flat surfaces is particularly critical for applications in transfer printing, robotics, and precision manufacturing. In these areas, adhesion-controlled grasping of complex three-dimensional surfaces is very challenging because the adhesive must be soft enough to enable intimate contact under light pressure but stiff enough to support high load and fracture strength.
“Until now, there has been a fundamental trade-off between soft, mechanically compliant interfaces and high adhesion strength,” said Metin Sitti, a director in Max Planck Institute for Intelligent Systems. “With this soft gripping system, we’ve demonstrated that you can have both.”
Sitti, also an adjunct professor of mechanical engineering at Carnegie Mellon University, has long focused his research on the unique features of the gecko lizard.
Mimics Gecko to Pick up Objects
|A soft adhesion-based gripping system supporting various 3D objects.
(Credit: Sukho Song)
The gripping system contains a soft adhesive membrane with microscopic pillars that are inspired by the sticky foot hairs on a gecko’s foot. The membrane is supported by a deformable gripper body that controls the gripping strength of the adhesive through changes in internal air pressure. It exhibits enhanced and robust adhesion on various sizes of curved and deformable surfaces, outperforming other adhesion methods.
Another area of application for this soft gripping system is in personal robotics.
Carmel Majidi, an associate professor of mechanical engineering at Carnegie Mellon, said:
“One day, we might have robots that act as assistants and care-givers—for example, a robot that can help unload a dishwater or manage medication. The ability for the robot to manipulate a broad range of objects is crucial.”
The researchers have tested their gripper by picking up a wide variety of everyday objects such as a coffee cup, a cherry tomato and even a plastic bag filled with candy—they found it capable of picking up objects weighing up to 300 grams. They report that their gripper works as conceived and that it outperforms other gripping systems. They suggest also that it could be easily scaled by using multiple grippers to pick up heavier objects, though they note testing still needs to be done to determine if the materials they used are durable enough to stand up to real world conditions.
Majidi and Sitti acknowledge Sukho Song and Dirk-Michael Drotlef in performing this multidisciplinary research and the Max Planck Society for the financial support. Majidi also acknowledges support from the Office of Naval Research.
Source: Carnegie Mellon University