Engineers at the Massachusetts Institute of Technology (MIT) and their collaborators have designed a microfluidic device they call a "tree-on-a-chip" which mimics the pumping mechanism of trees and plants.
Like its natural counterparts, the chip operates passively, requiring no moving parts or external pumps.
It is able to pump water and sugars through the chip at a steady flow rate for several days.
"The chip's passive pumping may be leveraged as a simple hydraulic actuator for small robots," said Anette "Peko" Hosoi, associate department head for operations in MIT's Department of Mechanical Engineering.
Engineers have found it difficult and expensive to make tiny, movable parts and pumps to power complex movements in small robots.
The team's new pumping mechanism may enable robots whose motions are propelled by inexpensive, sugar-powered pumps.
"In small robotics, if we could make the building blocks that enable cheap complexity, that would be super exciting. I think these [microfluidic pumps] are a step in that direction," Hosoi added.
Hosoi's co-authors on the paper are lead author Jean Comtet, a former graduate student in MIT's Department of Mechanical Engineering; Kaare Jensen of the Technical University of Denmark; and Robert Turgeon and Abraham Stroock, both of Cornell University.
Hosoi envisions that the "tree-on-a-chip" pump may be built into a small robot to produce hydraulically powered motions, without requiring active pumps or parts.
"If you design your robot in a smart way, you could absolutely stick a sugar cube on it and let it go," Hosoi said.
The results were published in the journal Nature Plants.