Tiny folding robot could be used for eye surgeries

Researchers have developed a tiny folding robot that could be used for microsurgery or micro-assembly.

The milliDelta robot was developed by a team at Harvard’s Wyss Institute for Biologically Inspired Engineering. It is a miniaturised version of the Delta robots which are employed in many industrial processes, and use three individually controlled arms to move fast and accurately in three directions.

Researchers have shrunk these robots down over the years for use in smaller tasks, but conventional manufacturing techniques have seen their efforts to make them even tinier hit a wall.

Researchers at the Wyss institute overcame this challenge by using high-performance composite materials which incorporate joints and bending actuators. They combined this with an origami-inspired manufacturing technique where the robots can be assembled from flat sheets of composite materials. Their robot is just 15 x 15 x 20 millimetres.

“The physics of scaling told us that bringing down the size of Delta robots would increase their speed and acceleration, and pop-up MEMS manufacturing with its ability to use any material or combination of materials seemed an ideal way to attack this problem,” said group leader Robert Wood. “This approach also allowed us to rapidly go through a number of iterations that led us to the final milliDelta.”

The tiny robot can operate in a workspace of just seven cubic millimetres, and can apply enough force to be able to be used in industrial pick-and-place processes, or tiny surgeries like those on the retina.

The researchers think it could be used as a hand-tremor cancelling device in such surgeries – either added to existing robotic technology, or acting as stand-alones.  “We first mapped the paths that the tip of a toothpick circumscribed when held by an individual, computed those, and fed them into the milliDelta robot, which was able to match and cancel them out," said co-first author Fatma Zeynep Temel.