Robotic arm gets two opposable thumbs up

By Caitlin Kasunich

It was so easy, even a monkey could do it.

With more doctors and scientists developing new,… It was so easy, even a monkey could do it.

With more doctors and scientists developing new, innovative technology, an ordinary person might believe the possibility of creating movie-like super powers could lie directly beneath his or her fingertips.

In fact, for the past four years, University of Pittsburgh Medical Center researchers have been working on a project that involves one well-known super power: controlling one’s environment with the mind.

This became the case when the researchers decided to teach a rhesus monkey to use a robotic arm to feed itself by simply thinking about the action.

Andrew Schwartz, the principal investigator of this project and a neurobiology professor at Pitt, said he has worked as a scientist interested in the cortical control of arms for close to 25 years and decided to do a spin-off of the basic research effort.

“We started in the early 1990s at Arizona State University in the bioengineering program. Our initial funding came from the Whitaker Foundation. We then began a string of contracts and grants from [the National Institutes of Health], specifically from the Neural Prosthesis Program,” said Schwartz.

From there, Schwartz and his team worked together on the pilot project to show that it is possible to control a prosthetic arm using brain activity.

Meel Velliste, a research assistant professor at Pitt’s School of Medicine, observed the monkey’s movements.

“The monkey can control the arm to move in arbitrary positions and can open and close the gripper on the arm,” said Velliste.

Because of its high precision and controllability, Schwartz said researchers are using a commercially available robot arm made for research purposes.

“The joints are also ‘back-drivable,’ meaning that they will yield when pushed against. This allows us to build in a springiness to the arm that makes it feel alive and helps us to generate movements that seem natural,” Schwartz added.

Aaron Batista, an assistant professor of bioengineering at Pitt’s Swanson School of Engineering, said that human beings are already being helped by neural prostheses like the one Dr. Schwartz is developing.

“Dr. Schwartz and his students have enabled monkeys to control a robotic arm moving in three dimensions,” he said. “This device, given to a patient, would give them a degree of independence.”

Velliste also agreed that the project could be applied to humans in the future.

“With quadriplegic patients with no ability to move, we could record brain signals to restore the ability to manipulate their surrounding environment,” he said.

“We are extending this work to the operation of a wrist and hand,” said Schwartz. “In the future, we would like patients to be able to carry out the natural hand movements needed to be self-sufficient in daily activities.”

Batista acknowledged that it will be years before neural prosthetics will become a truly feasible option for individuals with motor impairments.